Waters 432 Conductivity Detector · Waters 432 Conductivity Detector Operator’s Guide 34 Maple...

Waters 432 Conductivity Detector

Operator’s Guide

34 Maple StreetMilford, MA 01757

71500043202, Revision A

NOTICE

The information in this document is subject to change without notice and should not be construed as a commitment by Waters Corporation. Waters Corporation assumes no responsibility for any errors that may appear in this document. This document is believed to be complete and accurate at the time of publication. In no event shall Waters Corporation be liable for incidental or consequential damages in connection with or arising from the use of this document.

1994 –2003 WATERS CORPORATION. PRINTED IN THE UNITED STATES OF AMERICA. ALL RIGHTS RESERVED. THIS DOCUMEBNT OR PARTS THEREOF MAY NOT BE REPRODUCED IN ANY FORM WITHOUT THE WRITTEN PERMISSION OF THE PUBLISHER.

Alliance, Millennium, and Waters are registered trademarks, and Empower, LAC/E, PowerLine, SAT/IN, Sep-Pak, UltraWISP, and WISP are trademarks of Waters Corporation.

All other trademarks or registered trademarks are the sole property of their respective owners.

Note: When you use the instrument, follow generally accepted procedures for quality control and methods development.

If you observe a change in the retention of a particular compound, in the resolution between two compounds, or in peak shape, immediately determine the reason for the changes. Until you determine the cause of a change, do not rely on the separation results.

Note: The Installation Category (Overvoltage Category) for this instrument is Level II. The Level II Category pertains to equipment that receives its electrical power from a local level, such as an electrical wall outlet.

STOPAtención: Changes or modifications to this unit not expressly approved by the party responsible for compliance could void the user’s authority to operate the equipment.

Important : Toute modification sur cette unité n’ayant pas été expressément approuvée par l’autorité responsable de la conformité à la réglementation peut annuler le droit de l’utilisateur à exploiter l’équipement.

Achtung: Jedwede Änderungen oder Modifikationen an dem Gerät ohne die ausdrückliche Genehmigung der für die ordnungsgemäße Funktionstüchtigkeit verantwortlichen Personen kann zum Entzug der Bedienungsbefugnis des Systems führen.

Avvertenza: eventuali modifiche o alterazioni apportate a questa unità e non espressamente approvate da un ente responsabile per la conformità annulleranno l’autorità dell’utente ad operare l’apparecchiatura.

Atención: cualquier cambio o modificación efectuado en esta unidad que no haya sido expresamente aprobado por la parte responsable del cumplimiento puede anular la autorización del usuario para utilizar el equipo.

Caution: Use caution when working with any polymer tubing under pressure:

• Always wear eye protection when near pressurized polymer tubing.

• Extinguish all nearby flames.

• Do not use Tefzel tubing that has been severely stressed or kinked.

• Do not use Tefzel tubing with tetrahydrofuran (THF) or concentrated nitric or sulfuric acids.

• Be aware that methylene chloride and dimethyl sulfoxide cause Tefzel tubing to swell, which greatly reduces the rupture pressure of the tubing.

Attention : Soyez très prudent en travaillant avec des tuyaux de polymères sous pression :

• Portez toujours des lunettes de protection quand vous vous trouvez à proximité de tuyaux de polymères.

• Eteignez toutes les flammes se trouvant à proximité.

• N'utilisez pas de tuyau de Tefzel fortement abîmé ou déformé.

• N'utilisez pas de tuyau de Tefzel avec de l'acide sulfurique ou nitrique, ou du tétrahydrofurane (THF).

• Sachez que le chlorure de méthylène et le sulfoxyde de diméthyle peuvent provoquer le gonflement des tuyaux de Tefzel, diminuant ainsi fortement leur pression de rupture.

Vorsicht: Bei der Arbeit mit Polymerschläuchen unter Druck ist besondere Vorsicht angebracht:

• In der Nähe von unter Druck stehenden Polymerschläuchen stets Schutzbrille tragen.

• Alle offenen Flammen in der Nähe löschen.

• Keine Tefzel-Schläuche verwenden, die stark geknickt oder überbeansprucht sind.

• Tefzel-Schläuche nicht für Tetrahydrofuran (THF) oder konzentrierte Salpeter- oder Schwefelsäure verwenden.

• Durch Methylenchlorid und Dimethylsulfoxid können Tefzel-Schläuche quellen; dadurch wird der Berstdruck des Schlauches erheblich reduziert.

Precauzione: prestare attenzione durante le operazioni con i tubi di polimero sotto pressione:

• Indossare sempre occhiali da lavoro protettivi nei pressi di tubi di polimero pressurizzati.

• Estinguere ogni fonte di ignizione circostante.

• Non utilizzare tubi Tefzel soggetti a sollecitazioni eccessive o incurvati.

• Non utilizzare tubi Tefzel contenenti tetraidrofurano (THF) o acido solforico o nitrico concentrato.

• Tenere presente che il cloruro di metilene e il dimetilsolfossido provocano rigonfiamento nei tubi Tefzel, che riducono notevolmente il limite di pressione di rottura dei tubi stessi.

Advertencia: manipular con precaución los tubos de polímero bajo presión:

• Protegerse siempre los ojos en las proximidades de tubos de polímero bajo presión.

• Apagar todas las llamas que estén a proximidad.

• No utilizar tubos Tefzel que hayan sufrido tensiones extremas o hayan sido doblados.

• No utilizar tubos Tefzel con tetrahidrofurano (THF) o ácidos nítrico o sulfúrico concentrados.

• No olvidar que el cloruro de metileno y el óxido de azufre dimetilo dilatan los tubos Tefzel, lo que reduce en gran medida la presión de ruptura de los tubos.

Caution: The user shall be made aware that if the equipment is used in a manner not specified by the manufacturer, the protection provided by the equipment may be impaired.

Attention : L’utilisateur doit être informé que si le matériel est utilisé d’une façon non spécifiée par le fabricant, la protection assurée par le matériel risque d’être défectueuses.

Vorsicht: Der Benutzer wird darauf aufmerksam gemacht, dass bei unsachgemäßer Verwenddung des Gerätes unter Umständen nicht ordnungsgemäß funktionieren.

Precauzione: l’utente deve essere al corrente del fatto che, se l’apparecchiatura viene usta in un modo specificato dal produttore, la protezione fornita dall’apparecchiatura potrà essere invalidata.

Advertencia: el usuario deberá saber que si el equipo se utiliza de forma distinta a la especificada por el fabricante, las medidas de protección del equipo podrían ser insuficientes.

Caution: To protect against fire hazard, replace fuses with those of the same type and rating.

Attention : Remplacez toujours les fusibles par d’autres du même type et de la même puissance afin d’éviter tout risque d’incendie.

Vorsicht: Zum Schutz gegen Feuergefahr die Sicherungen nur mit Sicherungen des gleichen Typs und Nennwertes ersetzen.

Precauzione: per una buona protezione contro i rischi di incendio, sostituire i fusibili con altri dello stesso tipo e amperaggio.

Advertencia: sustituya los fusibles por otros del mismo tipo y características para evitar el riesgo de incendio.

Caution: To avoid possible electrical shock, disconnect the power cord before servicing the instrument.

Attention : Afin d’éviter toute possibilité de commotion électrique, débranchez le cordon d’alimentation de la prise avant d’effectuer la maintenance de l’instrument.

Vorsicht: Zur Vermeidung von Stromschlägen sollte das Gerät vor der Wartung vom Netz getrennt werden.

Precauzione: per evitare il rischio di scossa elettrica, scollegare il cavo di alimentazione prima di svolgere la manutenzione dello strumento.

Precaución: para evitar descargas eléctricas, desenchufe el cable de alimentación del instrumento antes de realizar cualquier reparación.

Commonly Used Symbols

Direct currentCourant continuGleichstromCorrente continuaCorriente continua

Alternating currentCourant alternatifWechselstromCorrente alternataCorriente alterna

Protective conductor terminalBorne du conducteur de protectionSchutzleiteranschlussTerminale di conduttore con protezioneBorne del conductor de tierra

Frame or chassis terminalBorne du cadre ou du châssisRahmen- oder ChassisanschlussTerminale di struttura o telaioBorne de la estructura o del chasis

Caution or refer to manualAttention ou reportez-vous au guideVorsicht, oder lesen Sie das HandbuchPrestare attenzione o fare riferimento alla guidaActúe con precaución o consulte la guía

Caution, hot surface or high temperatureAttention, surface chaude ou température élevéeVorsicht, heiße Oberfläche oder hohe TemperaturPrecauzione, superficie calda o elevata temperaturaPrecaución, superficie caliente o temperatura elevada

Commonly Used Symbols (Continued)

Caution, risk of electric shock (high voltage)Attention, risque de commotion électrique (haute tension)Vorsicht, Elektroschockgefahr (Hochspannung)Precauzione, rischio di scossa elettrica (alta tensione)Precaución, peligro de descarga eléctrica (alta tensión)

Caution, risk of needle-stick punctureAttention, risques de perforation de la taille d’une aiguilleVorsicht, Gefahr einer SpritzenpunktierungPrecauzione, rischio di puntura con agoPrecaución, riesgo de punción con aguja

Caution, ultraviolet lightAttention, rayonnement ultrvioletVorsicht, Ultraviolettes LichtPrecauzione, luce ultraviolettaPrecaución, emisiones de luz ultravioleta


UV

FuseFusibleSicherungFusibileFusible

Electrical power onSous tensionNetzschalter einAlimentazione elettrica attivataAlimentación eléctrica conectada

Electrical power offHors tensionNetzschalter ausAlimentazione elettrica disattivataAlimentación eléctrica desconectada


1

0

432 Conductivity Detector Information

Intended Use

The Waters®

432 Conductivity Detector can be used for in-vitro diagnostic testing to analyze many compounds, including diagnostic indicators and therapeutically monitored compounds. When you develop methods, follow the “Protocol for the Adoption of Analytical Methods in the Clinical Chemistry Laboratory,” American Journal of Medical Technology, 44, 1, pages 30–37 (1978). This protocol covers good operating procedures and techniques necessary to validate system and method performance.

Biological Hazard

When you analyze physiological fluids, take all necessary precautions and treat all specimens as potentially infectious. Precautions are outlined in “CDC Guidelines on Specimen Handling,” CDC – NIH Manual, 1984.

Calibration

Follow acceptable methods of calibration with pure standards to calibrate methods. Use a minimum of five standards to generate a standard curve. The concentration range should cover the entire range of quality-control samples, typical specimens, and atypical specimens.

Quality Control

Routinely run three quality-control samples. Quality-control samples should represent subnormal, normal, and above-normal levels of a compound. Ensure that quality-control sample results are within an acceptable range, and evaluate precision from day to day and run to run. Data collected when quality-control samples are out of range may not be valid. Do not report this data until you ensure that chromatographic system performance is acceptable.

Table of Contents

Preface ....................................................................................... 23

Chapter 1 Introduction ...................................................................................... 26

Chapter 2 Installing the Detector ...................................................................... 30

2.1 Selecting the Installation Site................................................ 30

2.2 Unpacking and Inspection..................................................... 31

2.3 AC Power Connection ........................................................... 32

2.4 I/O Signal Connections ......................................................... 35

2.4.1 I/O Signal Descriptions .............................................. 35

2.4.2 PowerLine Controller Connections ............................ 37

2.4.3 Empower and Millennium32 Connections .................. 39

2.4.4 Data Module Connections ......................................... 44

2.4.5 Chart Recorder Connections ..................................... 45

2.4.6 Chart Marker Input Connections................................ 45

2.4.7 Auto Zero Input Connections ..................................... 46

2.4.8 Alliance Separations Module Connections ................ 46

2.5 Making Fluidic Connections .................................................. 48

2.6 Passivating the System......................................................... 53

2.7 Verifying the Detector............................................................ 54

Table of Contents 15

Chapter 3 Operating the Detector .................................................................... 56

3.1 Controls and Indicators ......................................................... 56

3.2 Startup and Shutdown .......................................................... 61

3.3 Operating Recommendations ............................................... 62

Chapter 4 Performing Ion Analysis ................................................................... 64

4.1 Fundamental Considerations ................................................ 64

4.2 Configuring the System......................................................... 68

4.3 Eluents for Ion Analysis......................................................... 69

4.3.1 Preparing Anion Eluent.............................................. 70

4.3.2 Preparing Cation Eluent ............................................ 70

4.4 Standards for Ion Analysis .................................................... 70

4.4.1 Preparing Anion Standards ....................................... 71

4.4.2 Injecting Anion Standards.......................................... 72

4.4.3 Preparing Cation Standards ...................................... 74

4.4.4 Injecting Cation Standards......................................... 76

Chapter 5 Maintenance .................................................................................... 78

5.1 Routine Maintenance ............................................................ 78

5.1.1 Replacing the Fuse.................................................... 78

5.1.2 Maintaining the Flow Cell........................................... 79

5.2 Cleaning the Detector Exterior.............................................. 82

5.3 Troubleshooting..................................................................... 82


Appendix A Specifications ................................................................................... 87

Appendix B Spare Parts....................................................................................... 90

Appendix C Ion Chromatography Methods .......................................................... 91

C.1 General-Purpose Anion Analysis Using Conductivity and UV Detection ................................................................ 91

C.1.1 Preparing Eluent ....................................................... 93

C.1.2 Preparing Standards ................................................. 93

C.1.3 Preparing a Sample .................................................. 93

C.1.4 Empower Data Processing Method........................... 94

C.1.5 Method Validation ..................................................... 95

C.1.6 Method Linearity........................................................ 95

C.1.7 Quantitation Precision............................................... 97

C.1.8 Method Detection Limits............................................ 97

C.1.9 Quantitation Accuracy ............................................... 98

C.1.10 Analyte Recovery .................................................... 99

C.1.11 Example of Use..................................................... 100

C.1.12 Using Direct UV Detection .................................... 100

C.1.13 Preparing Lithium Borate/Gluconate 50X Stock Concentrate ................................................... 102

C.1.14 Preparing Lithium Borate/Gluconate Eluent.......... 102


C.2 Alkali and Alkaline Earth Cations, Ammonium, and Amines........................................................................ 103

C.2.1 Preparing Eluent .................................................... 104

C.2.2 Preparing Standards ............................................... 104

C.2.3 Preparing a Sample ................................................ 105

C.2.4 Empower Data Processing Method......................... 105

C.2.5 Method Detection Limits.......................................... 106

C.2.6 Examples of Use..................................................... 107

C.2.7 Preparing Stock Reagent ........................................ 108

Appendix D Validation Support .......................................................................... 109

Index ..................................................................................... 111


List of Figures

1-1 Waters 432 Conductivity Detector ................................................. 261-2 Flow Cell Schematic ...................................................................... 28

2-1 Rear Panel ..................................................................................... 332-2 Changing the Voltage Setting ........................................................ 342-3 I/O Terminal Strip........................................................................... 362-4 IEEE-488 Address Switch.............................................................. 382-5 Bus SAT/IN Module (Front Panel) .................................................. 402-6 Bus SAT/IN to Bus LAC/E Connections ......................................... 422-7 Bus SAT/IN to 432 Detector Connections...................................... 432-8 Alliance Separations Module Connections to the 432

Detector Auto-Zero on Inject.......................................................... 472-9 Alliance Separations Module Connections to the 432

Detector Chart Mark on Inject........................................................ 482-10 Fluid Connections .......................................................................... 492-11 Cutting Polymeric Tubing ............................................................... 502-12 Ferrule and Compression Screw Assembly................................... 512-13 Pulse Dampener ............................................................................ 53

3-1 Front Panel .................................................................................... 56

4-1 Soda Lime Tube............................................................................. 674-2 System Configuration for Ion Analysis........................................... 684-3 Chromatogram of a 7-Anion Standard........................................... 744-4 Chromatogram of an 8-Cation Standard........................................ 77

5-1 Installing Operating Voltage Fuses ................................................ 795-2 Flow Cell Assembly ....................................................................... 81

C-1 Common Anion Standards ............................................................ 92

List of Figures 19

C-2 Calibration Curves for Chloride, Fluoride, and Bromide ............... 95C-3 Calibration Curves for Nitrite and Nitrate ...................................... 96C-4 Calibration Curves for Sulfate and Phosphate .............................. 96C-5 100-mL Injection ........................................................................... 97C-6 Typical Drinking Water, No Dilution Required ............................ 100C-7 Direct UV Detection .................................................................... 101C-8 100-ppb Anion Standard ............................................................. 101C-9 1-ppm Standard .......................................................................... 103C-10 25-ppb Cation Standard .............................................................. 106C-11 Typical Drinking Water, No Dilution Required ............................ 107C-12 Typical Municipal Wastewater, Diluted 1:50, Overlay

of Duplicate Injections.................................................................. 107

List of Figures 20

List of Tables

1-1 Limiting Equivalent Conductance of Ions in Water at 25 °C ......... 29

2-1 Power Cord Wire Identification ..................................................... 332-2 Nominal Operating Voltage...................................................... 342-3 I/O Signal Descriptions ........................................................... 362-4 IEEE-488 DIP Switch Setting .................................................. 382-5 Bus SAT/IN Cable Connections ............................................... 442-6 Data Module Signal Cable Connections .................................. 442-7 Data Module Chart Mark Cable Connections........................... 452-8 Chart Recorder Cable Connections......................................... 452-9 Autosampler Chart Mark Cable Connections ........................... 462-10 Autosampler Auto Zero Cable Connections ............................. 462-11 Connections for Generating Auto-Zero on Inject ...................... 472-12 Connections for Generating Chart Mark on Inject .................... 48

3-1 Key Descriptions ........................................................................... 583-2 Setting the Beep Function ....................................................... 60

4-1 Shelf-Life of Standards ................................................................. 714-2 Salts for Anion Standard Concentrates.................................... 724-3 Anion Concentrate Dilutions .................................................... 724-4 Salts for Cation Standard Concentrates .................................. 754-5 Cation Concentrate Dilutions................................................... 75

5-1 Troubleshooting Guide .................................................................. 85

A-1 Operational Specifications ............................................................ 87A-2 Mechanical Specifications ............................................................ 87A-4 Electrical Specifications ................................................................ 88A-3 Environmental Specifications........................................................ 88

List of Tables 21

A-5 Communications ........................................................................... 89

B-1 Spare Parts ................................................................................... 90

C-1 Required Instrumentation ............................................................. 91

C-1 Analysis Conditions ...................................................................... 92C-2 IC Processing Method Using Peak Apex for Retention Time ....... 94C-3 Method Validation ......................................................................... 95C-4 Quantitation Precision................................................................... 97C-5 Quantitation Accuracy................................................................... 98C-6 Analyte Recovery.......................................................................... 99

C-1 Required Instrumentation ........................................................... 103C-2 Analysis Conditions .................................................................... 104C-3 IC Processing Method Using Peak Apex for Retention Time ..... 105

List of Tables 22

Preface

The Waters 432 Conductivity Detector Operator’s Guide details the procedures for unpacking, installing, operating, maintaining, and troubleshooting the 432 Conductivity Detector. It also includes appendixes listing specifications and spare parts and describing validation support.

This guide is intended for use by personnel who need to install, operate, maintain, or troubleshoot the 432 Detector. This guide assumes an understanding of the principles of chromatography.

Organization

This guide contains the following:

Chapter 1 describes the features and method of operation of the 432 Detector.

Chapter 2 describes the procedures for installing the 432 Detector and making fluid and electrical connections.

Chapter 3 describes the controls and indicators of the 432 Detector, and provides general operating instructions.

Chapter 4 describes the system configuration, eluents, and standards recommended for anion and cation analysis.

Chapter 5 describes simple maintenance procedures and provides troubleshooting tables to aid in problem diagnosis.

Appendix A describes the operational specifications and requirements of the 432 Detector.

Appendix B lists the recommended spare parts for the 432 Detector.

Appendix C describes ion chromatography methods.

Appendix D describes the recommended validation protocols and Waters®

validation support.

Related Documentation

Waters Licenses, Warranties, and Support: Provides software license and warranty information, describes training and extended support, and tells how Waters handles shipments, damages, claims, and returns.

23

Documentation on the Web

Related product information and documentation can be found on the World Wide Web. Our address is http://www.waters.com.

Related Adobe Acrobat Reader Documentation

For detailed information about using Adobe® Acrobat® Reader, see the Adobe Acrobat Reader Online Guide. This guide covers procedures such as viewing, navigating, and printing electronic documentation from Adobe Acrobat Reader.

Printing This Electronic Document

Adobe Acrobat Reader lets you easily print pages, page ranges, or the entire document by selecting File > Print. For optimum print quantity, Waters recommends that you specify a PostScript® printer driver for your printer. Ideally, use a printer that supports 600 dpi print resolution.

Documentation Conventions

The following conventions can be used in this guide:

Convention Usage

Purple Purple text indicates user action such as keys to press, menu selec-tions, and commands. For example, “Click Next to go to the next page.”

Italic Italic indicates information that you supply such as variables. It also indicates emphasis and document titles. For example, “Replace file_name with the actual name of your file.”

Courier Courier indicates examples of source code and system output. For example, “The SVRMGR> prompt appears.”

Courier Bold Courier bold indicates characters that you type or keys you press in examples of source code. For example, “At the LSNRCTL> prompt, enter set password oracle to access Oracle.”

Underlined Blue Indicates hypertext cross-references to a specific chapter, section, subsection, or sidehead. Clicking this topic using the hand symbol brings you to this topic within the document. Right-clicking and selecting Go Back from the shortcut menu returns you to the origi-nating topic. For example, “The detector’s I/O signals are described in Section 2.4, I/O Signal Connections.”

Keys The word key refers to a computer key on the keypad or keyboard. Screen keys refer to the keys on the instrument located immediately below the screen. For example, “The A/B screen key on the 2414 Detector displays the selected channel.”

24

http://www.waters.com

Notes

Notes call out information that is helpful to the operator. For example:

Note: Record your result before you proceed to the next step.

Attentions

Attentions provide information about preventing damage to the system or equipment. For example:

Cautions

Cautions provide information essential to the safety of the operator. For example:

… Three periods indicate that more of the same type of item can optionally follow. For example, “You can store filename1, filename2, … in each folder.”

> A right arrow between menu options indicates you should choose each option in sequence. For example, “Select File > Exit” means you should select File from the menu bar, then select Exit from the File menu.

STOPAttention: To avoid damaging the detector flow cell, do not touch the flow cell window.

Caution: To avoid burns, turn off the lamp at least 30 minutes before removing it for replacement or adjustment.

Caution: To avoid electrical shock and injury, unplug the power cord before performing maintenance procedures.

Caution: To avoid chemical or electrical hazards, observe safe laboratory practices when operating the system.

Convention Usage

25

1
Chapter 1IntroductionFeatures
The Waters® 432 Conductivity Detector (Figure 1-1) is specifically designed to be integrated into chromatographic systems. The following features contribute to its performance in measuring the conductivity of column eluents:

• Unique 5-electrode flow cell design

• Heat exchanger and a built-in automatic temperature control system for stable operation

• Auto baseline/auto zero

• External recorder/integrator and chart mark connections

• Three time constant selections

• “Leak-detected” alarm signal

Figure 1-1 Waters 432 Conductivity Detector

TP01268

IN OUT

Waters 432Conductivity Detector

26

1

Method of Operation

This section discusses the method of operation of the 432 Detector. Additional descriptive information appears in these sections:

• Section 2.4.1, I/O Signal Descriptions

• Section 3.1, Controls and Indicators

• Appendix A, Specifications

Measurement Technique

The 432 Detector responds to all ions present in the flow cell, since all ions in solution conduct electricity. This allows the 432 Detector to detect a wide variety of sample ions.

The 432 Detector eliminates the eluent’s contribution to conductivity with an electronic technique called baseline suppression. The detector measures the eluent conductivity and assigns it a value of zero. Thus, any sample ions appear as positive or negative measurements, relative to the baseline.

The temperature of an ionic solution affects the conductivity of the ions. Generally, a solution’s conductivity rises about 2% for every degree Celsius of temperature increase. The special flow cell heater in the 432 Detector minimizes the effect of ambient temperature fluctuations on measurement accuracy.

Flow Cell Design

The flow cell in the 432 Detector contains five electrodes connected in a measuring circuit: two reference electrodes, two detection electrodes, and a guard electrode that provides a local electrical “ground” (Figure 1-2). Column eluent flows through the heater to attain the set temperature, and then flows through the cell, directly contacting the electrodes. The 5-electrode design permits measurement of conductivity to be made with a very low current at the detection electrodes. The low current employed eliminates impedance and other problems associated with simpler designs, and results in a stable baseline and an extended range of linearity.

Introduction 27

1

Figure 1-2 Flow Cell Schematic

Ion Detection Theory

The conductance of a solution of known concentration can be calculated using the following equation:

G = measured conductance of the solution, in Siemens (1 S = ohm−1)

C = concentration in equivalents per 1000 cm3

K = length/area of cell (the cell constant)

λ = equivalent conductance in S cm2 equiv−1

Table 1-1 lists the equivalent conductances of some common ions.1 Concentrations above 10−5 to 10−3 N, generally exhibit decreased equivalent conductance due to interionic effects.

TP01271

1

3 2

Flow Cell Block (heated)

Fluid Outlet

1= Reference Electrodes2= Detection Electrodes3= Guard Electrode

GλC

10 3–----------=

28

1

1. Henry H. Bauer et al., eds. “Instrumental Analysis,” Allyn and Bacon, Boston (1978), p. 115. Reprinted with permission from the publisher.

Table 1-1 Limiting Equivalent Conductance of Ions in Water at 25 °C

Cations l + Anions λ —

H + 349.8 OH − 198.6

Li + 38.6 F − 55.4

Na + 50.1 Cl − 76.4

K + 73.5 Br − 78.1

Rb + 77.8 I − 76.8

Ag + 61.9 NO3 − 71.5

NH4 + 73.3 ClO3

− 64.6

(CH3)2NH2 + 51.8 ClO4

− 67.4

Hg 2+ 53.0 IO4 − 54.5

Mg 2+ 53.1 Formate 54.6

Ca 2+ 59.5 Acetate 40.9

Ba 2+ 63.6 Benzoate 32.4

Cu 2+ 53.6 SO4 2− 80.0

Zn 2+ 52.8 CO3 2− 69.3

La 3+ 69.7 Fe(CN)6 4− 111.0

Ce 3+ 69.8

Introduction 29

2

Chapter 2Installing the Detector

This chapter guides you through the following steps in preparing the 432 Detector for operation in a chromatographic system:

• Selecting an installation site that satisfies the detector’s power and environmental requirements

• Unpacking and inspecting the 432 Detector and accompanying items

• Connecting the detector to your AC power supply

• Connecting the detector electrically to the other components of your chromatographic system

• Connecting the detector inlet to the column and the detector outlet to a waste receptacle (and, if required, installing the pulse dampener)

• Passivating the detector and other post-column fluid path components

After you have successfully completed this chapter, familiarize yourself with the information in Section 3.1, Controls and Indicators. When you are ready to operate the detector, perform the startup procedure described in Section 3.2, Startup and Shutdown.

2.1 Selecting the Installation Site

Operating Environment

The 432 Detector operates in any standard laboratory environment that provides suitable electrical power and remains within the following ranges:

• Temperature: 5 to 35 °C (40 to 95 °F)

• Humidity: 20 to 80%, noncondensing

Install the instrument in a clean area that is free from exposure to:

• Temperature or humidity extremes, which can be found near direct sunlight, heat registers, and air conditioning vents

• Strong electromagnetic radiation, such as from large motors or arcing contacts

• Appreciable shock or vibration

Selecting the Installation Site 30

2

Required Space

The 432 Detector requires bench space that measures approximately:

• 10 inches (25 cm) high

• 14 inches (34 cm) wide

• 24 inches (60 cm) deep

Power Requirements

The 432 Detector requires:

• One properly grounded AC voltage outlet.

• Correct voltage and fuse selections as shown in Table 2-2.

2.2 Unpacking and Inspection

Unpacking

The 432 Detector is shipped in one carton that contains the following items:

• Waters 432 Conductivity Detector

• Startup Kit

• Validation certificate

• Waters 432 Conductivity Detector Operator’s Guide

• Packing list

• Declaration of conformity

Note: If you purchased the 432 Detector as part of an ion/liquid chromatograph system, a Waters representative will perform the installation and startup.

To unpack the 432 Detector:

1. Locate the packing list.

2. Unpack the contents of the shipping carton and check the contents against the packing list to make sure that you received all items.

3. Check the contents of the Startup Kit against the Waters 432 Conductivity Detector Startup Kit List.

4. Save the shipping carton for future transport or shipment.

STOPAttention: Make sure that air can circulate freely through the ventilation slots on both side panels.

Installing the Detector 31

2

Inspection

Inspect all items. If you find any damage or discrepancy, immediately contact the shipping agent and Waters. For more information about the instrument warranty, refer to Waters Licenses, Warranties, and Support.

If the shipment is complete and undamaged, record the installation date and serial number of the 432 Detector in the spaces provided in Appendix B, Spare Parts.

2.3 AC Power Connection

Power Cord

The power connector is located on the lower-right corner of the rear panel, as shown in Figure 2-1. If a power plug other than the one supplied is needed for your location, consult Table 2-1 and observe the existing applicable regulations.

Caution: To avoid a potential fire hazard and damage to the 432 Detector, make sure that the voltage selector in the power connector is set correctly to match the available AC power source, and that the correct fuses are installed before you apply AC power.

AC Power Connection 32

2

Figure 2-1 Rear Panel

The 432 Detector can be adapted to operate within two voltage ranges at 50 or 60 Hz. Table 2-2 describes these voltage ranges and the fuse value that is appropriate to each.

Table 2-1 Power Cord Wire Identification

Wire (USA) Wire (International) Connection

Black Brown Hot

White Blue Neutral

Green Green/Yellow Ground (Earth)

IEEE DIPSwitch Cover


2

Required Material

You need a flat-blade screwdriver to perform this procedure.

Procedure

To change the operating voltage setting:

1. Remove the power cord from its connector on the rear panel of the controller and pry open the power connector cover with a flat-blade screwdriver.

2. Remove the voltage selection barrel and locate the correct voltage setting (Figure 2-2).

3. Reinstall the voltage selection barrel so the desired voltage setting appears through the window when you close the power connector cover (Figure 2-2).

Figure 2-2 Changing the Voltage Setting

4. Determine if you need to change the fuses (see Table 2-2). All units are supplied with two 2-A fuses installed for 100/120 volt operation. If you operate the unit on 220/240 volt power, change the fuse as outlined in Section 5.1.1, Replacing Fuses.

5. Reinstall the power connector cover and the power cord.

Table 2-2 Nominal Operating Voltage

Nominal Voltage (VAC) Fuse

100/120 T 2A

220/240 T 1A

Caution: To avoid the possibility of electrical shock, turn off the front panel power switch and unplug the power cord.

Voltage Settings

AC Power Connection 34

2

2.4 I/O Signal Connections

The 432 Detector is usually installed as an integral part of a data collection system. You can control the 432 Detector either locally from the keypad on the front panel or remotely from a PowerLine™ controller, such as the Waters 600S.

This section describes the detector’s I/O signals and how they connect to the following devices:

• PowerLine controller

• Empower™ or Millennium®32

software

• Data module

• SAT/IN™ module

• Chart recorder

• Device signalling the Chart Marker input

• Device signalling the Auto Zero input

2.4.1 I/O Signal Descriptions

The 432 Detector rear panel has an IEEE-488 connector for communication with a PowerLine controller, and a terminal strip (Figure 2-3) for the input/output signals. These signals are described in Table 2-3.

STOPAttention: To meet the regulatory requirements of immunity from external electrical disturbances that may affect the performance of this instrument, do not use cables longer than 9.8 feet (3 meters) when connecting to the screw-type barrier terminal strips. In addition, ensure you always connect the shield of the cable to chassis ground at one instrument only.


2

Figure 2-3 I/O Terminal Strip

Table 2-3 I/O Signal Descriptions

Terminal Pairs Function

Rec (+ and –) Recorder output – A 10-mV full-scale analog output signal appears on these terminals. The measurement range is determined by the product of the Base Range and Sensitivity settings: for example, 500 µS (base range) x 0.005 (sensitivity) = 2.5 µS full scale.

Int (+ and –) Integrator output – A 1-V full-scale analog output signal appears on these terminals. The measurement range is selectable:10, 50, or 100 µS full scale.

Marker Out Marker output – A 1-second contact closure signal appears on these terminals when either of the following events occurs:• The Chart Mark key on the keypad is pressed• A contact closure signal occurs between the Marker In terminals

Leak Leak Alert output – A contact closure signal appears on these termi-nals if a leak is detected inside the detector.

Auto Zero (+ and –)

Auto Zero input – The voltage at the Recorder and Integrator output terminals is set to the user-selected balance offset level when a contact closure occurs between these terminals.

Marker In (+ and –)

Marker input – A chart mark (~0.5 mV for 3 seconds) is added to the Recorder output signal when a contact closure signal appears between these terminals.

+

–

+

–

+

–

+

–

INT

REC

LEAK

MARKERIN

MARKEROUT

AUTO ZERO

+–

+–

+–

+–

Int

Rec

Marker In

Auto Zero

Leak

Marker Out

I/O Signal Connections 36

2

Required Material

To connect cables to the I/O terminals, use a small flat-blade screwdriver.

Other Rear Panel Connections and DIP Switch

In addition to the I/O terminal strip, the rear panel also contains the following items:

• IEEE-488 connector – Communication bus for use with a Waters PowerLine system controller, such as the Waters 600S.

• DIP switch – Sets the IEEE-488 address seen by the system controller.

• Ground lugs – Used to connect the 432 Detector to an earth ground connection and also used as a chassis ground connection to other system instruments.

2.4.2 PowerLine Controller Connections

The 432 Detector can be programmed remotely by a PowerLine controller (such as the Waters 600S) via the IEEE-488 data communications bus.

Required Material

You need a 2.5-mm Allen wrench to connect to the 432 Detector.

Procedure

To connect the 432 Detector to a PowerLine controller:

1. Turn off the PowerLine controller and the 432 Detector.

2. Plug one end of the IEEE-488 cable (included in the Startup Kit) into the bus connector on the rear panel of the 432 Detector (Figure 2-1) and the other end of the cable into the bus connector on the PowerLine controller.

3. Remove the DIP switch cover (Figure 2-1) using a 2.5-mm Allen wrench.

4. Refer to Table 2-4 to set the DIP switches on the rear panel of the 432 Detector (Figure 2-4) to a unique IEEE-488 address between 2 and 29.

5. After you set the DIP switches, reinstall the DIP switch cover.

Note: To operate the 432 Detector in local mode, press the front panel Remote key. The illuminated light above the key will go out.


2
Figure 2-4 IEEE-488 Address Switch
The IEEE-488 address DIP switch employs positive logic to determine the address of the 432 Detector from the switch settings. Table 2-4 shows the settings for valid addresses.

Table 2-4 IEEE-488 DIP Switch Setting

IEEE-488 Address

DIP Switch Settings

1 2 3 4 5

2 OFF ON OFF OFF OFF

3 ON ON OFF OFF OFF

4 OFF OFF ON OFF OFF

5 ON OFF ON OFF OFF

6 OFF ON ON OFF OFF

7 ON ON ON OFF OFF

8 OFF OFF OFF ON OFF

9 ON OFF OFF ON OFF

10 OFF ON OFF ON OFF

11 ON ON OFF ON OFF

12 OFF OFF ON ON OFF

13 ON OFF ON ON OFF

14 OFF ON ON ON OFF

15 ON ON ON ON OFF

16 OFF OFF OFF OFF ON

17 ON OFF OFF OFF ON

18 OFF ON OFF OFF ON

19 ON ON OFF OFF ON

1 2 3 4 5

O F F

12

4

816

Switch 5Switch 1

(Address 8 Shown)


2

PowerLine Operation

Under PowerLine control, the 432 Detector is recognized as a 431 Detector and it retains the functionality of the 431 Detector with the following differences:

• The Balance field on the detector setup page of the PowerLine controller affects the Integrator Balance and the Integrator Output only.

• When you press the Setup key on the controller, the selected Balance value is sent to the 432 Detector from the PowerLine controller. However, the 432 Detector output does not change to the selected balance until the detector is autozeroed by a contact closure at the Auto Zero input terminals on the rear panel (remote or local mode) or when you press the Auto Zero key on the front panel (local mode only).

Under PowerLine control, the 432 Detector retains the full functionality of local mode operation, except for the following differences:

• The Recorder Sensitivity ranges of 0.0002 and 0.0001 are not accessible.

• The Integrator Sensitivity ranges are not accessible.

• The 432 Detector does not automatically perform an Auto Zero after an Auto Base routine has occurred.

2.4.3 Empower and Millennium32 Connections

Empower and Millennium32 software perform data acquisition, processing, and management of chromatographic information. This software requires the detector’s analog signal to be converted to a digital form.

20 OFF OFF ON OFF ON

21 ON OFF ON OFF ON

22 OFF ON ON OFF ON

23 ON ON ON OFF ON

24 OFF OFF OFF ON ON

25 ON OFF OFF ON ON

26 OFF ON OFF ON ON

27 ON ON OFF ON ON

28 OFF OFF ON ON ON

29 ON OFF ON ON ON

Table 2-4 IEEE-488 DIP Switch Setting (Continued)

IEEE-488 Address

DIP Switch Settings

1 2 3 4 5


2

Empower and Millennium32 are menu-driven applications specifically designed by Waters for chromatographers. Use the software to:

• Acquire data

• Process data

• Generate and print reports

• Store information (or data) in a central area and share this information with users who have proper security access

To connect the 432 Detector to an Empower or Millennium32 computer, be sure to:

• Connect the Bus Satellite Interface (SAT/IN) module to the Bus Laboratory Acquisition and Control/Environment (LAC/E™) card in the Empower computer, Millennium32 computer, acquisition client, or LAC/E32.

• Connect the 432 Detector to the Bus SAT/IN module (Channel 1 or 2).

• Remove the IEEE-488 cable from the rear panel of the 432 Detector, if it is connected.

The 432 Detector is in local mode when it is connected to an Empower and Millennium32 computer.

Bus SAT/IN Module

The Waters Bus SAT/IN module, shown in Figure 2-5, translates analog signals into digital form. It then transmits these digital signals to the Bus LAC/E card inside the workstation, acquisition client, or LAC/E32.

Figure 2-5 Bus SAT/IN Module (Front Panel)

1 2 3 4 5 6 7 8

CHANNEL 1 CHANNEL 2IN INOUT OUT

CH1

EVENTS

CH2

+ –

Waters SAT/IN Module

CH1

CH2 OK

+ –


2

Note: To prevent damage to the unit, always disconnect the power cord at either the wall outlet or the power supply before you attach or remove the power connection to the Bus SAT/IN module. The Bus SAT/IN module does not have a power switch.

Connecting the Bus SAT/IN Module to the Bus LAC/E Card

The Bus SAT/IN module connects to the Bus LAC/E through an I/O distribution box, as shown in Figure 2-6.

To connect the Bus SAT/IN module to the Bus LAC/E card:

1. Use the I/O distribution cable to connect the I/O distribution box to the 9-pin I/O distribution port on the Bus LAC/E card at the back of the Millennium

32 computer.

2. Use a serial cable to connect the data terminal on the back of the Bus SAT/IN to a port of the I/O distribution box.

3. Configure the serial port for the Bus SAT/IN module as described in the Empower or Millennium32 installation and configuration guides.


2

Figure 2-6 Bus SAT/IN to Bus LAC/E Connections

AC to DC Converter

I/O Distribution Por t (9-pin)of Bus LAC/E Card

I/O Distribution Box

Connect SAT/IN to Port 1 on theI/O Distribution Box

Modified ModularJack Connections

I/O Distribution Cable

PWRDATABCD

SAT/IN ModuleRear Panel

Serial Cable


2

Connecting the Bus SAT/IN Module to the 432 Detector

The Bus SAT/IN module connects to the 432 Detector as shown in Figure 2-7. Refer to the procedure following the figure and Table 2-5 for complete details.

Figure 2-7 Bus SAT/IN to 432 Detector Connections

To connect the 432 Detector to the Bus SAT/IN module:

1. Connect the white wire of the analog cable (included with the Bus SAT/IN module) to the Int + terminal on the rear panel of the 432 Detector. Connect the black wire to the Int – terminal.

2. Connect the other end of the cable to either the Channel 1 or Channel 2 connector on the front panel of the Bus SAT/IN module.

STOPAttention: To prevent damage to the unit, do not plug in the power cord of the Bus SAT/IN module until you perform all of the procedures described in the Waters Bus SAT/IN Module Installation Guide.

+

–

+

–

+

–

+

–

INT

REC

LEAK

MARKERIN

MARKEROUT

AUTO ZERO

TP01264

1 2 3 4 5 6 7 8

CHANNEL 1 CHANNEL 2

IN INOUT OUT

CH1

EVENTS

CH2

+ –

Waters SAT/IN Module

CH1

CH2 OK

Red

Black

Waters 432 Detector

+ –

White

Black


2

3. Connect the Event In terminals of the channel you chose in the previous step to the Inject Start output signal of the Waters Alliance

® solvent delivery system or the

Waters 717plus (or equivalent) Autosampler.

4. Remove the IEEE-488 cable from the rear panel of the 432 Detector, if it is connected.

The connections from the 432 Detector to the Bus SAT/IN are summarized in Table 2-5.

2.4.4 Data Module Connections

This section describes how to connect the analog output signal from the 432 Detector to the Waters 746 Data Module.

Analog Signal

To send the analog output signal from the 432 Detector to a Waters data module, connect the signal cable in the 432 Detector Startup Kit as described in Table 2-6.

Marker Out Signal

The Marker Out terminals of the 432 Detector provide a contact closure output signal when either of the following events occurs:

• Chart Mark key is pressed

• Marker In terminals are shorted together

Table 2-5 Bus SAT/IN Cable Connections

432 Detector I/O Connector Terminal

Bus SAT/INCable

Bus SAT/IN Connector

Int (+) White wire

Int (–) Black wire Channel 1 or 2

STOPAttention: Remember to meet the regulatory requirements of immunity from external electrical disturbances that may affect the performance of this instrument, do not use cables longer than 9.8 feet (3 meters) when connecting to the screw-type barrier terminal strips. In addition, ensure you always connect the shield of the cable to chassis ground.

Table 2-6 Data Module Signal Cable Connections

Wire432 Detector I/O

Connector Terminal746

Terminal

Red Int (+) (+)

Black Int (–) (–)

Shield Ground lug None


2

Use the signal to start a Waters 746 Data Module by connecting a signal cable to the module’s data cable (Table 2-7).

2.4.5 Chart Recorder Connections

To connect the 432 Detector to a chart recorder:

1. Attach the Recorder cable (see Appendix B, Spare Parts) to the 432 Detector REC output terminals, as indicated in Table 2-8.

2. Connect the cable shield to the ground lug on the 432 Detector rear panel.

3. Connect the other end of the cable to the 10-mV input terminals on the chart recorder, as indicated in Table 2-8.

2.4.6 Chart Marker Input Connections

The 432 Detector accepts a chart mark (start inject) signal from the following devices:

• Waters 717plus Autosampler

• Any other device that provides a compatible switch closure

Waters 717plus Autosampler

To connect the 432 Detector to a Waters 717/717plus Autosampler, connect a signal cable as indicated in Table 2-9.

Table 2-7 Data Module Chart Mark Cable Connections


Connector Terminal

746Cable

Either wire Marker Out Join to both Remote Start wires (white and red)

Other wire Marker Out Green wire

Table 2-8 Chart Recorder Cable Connections


Connector TerminalChart Recorder

Terminal

Red Rec (+) Pen (+)

Black Rec (–) Pen (–)


2

2.4.7 Auto Zero Input Connections

The voltage at the Recorder and Integrator outputs is set to the user-selected balance offset level when a contact closure occurs between the Auto Zero terminals. This section describes how to connect the 432 Detector to the following devices (so that an auto zero occurs at the injection point):

• Waters 717plus Autosampler

• Any other device that provides a compatible switch closure

Waters 717plus Autosampler

To connect the 432 Detector to a Waters 717plus Autosampler, connect a signal cable as indicated in Table 2-10.

2.4.8 Alliance Separations Module Connections

Connect the detector to Waters Alliance Separations Modules, when it is not under the control of the Millennium32 software, to perform the following tasks:

• Auto-Zero on inject

• Chart mark on inject

• Method start

Generating Auto-Zero on Inject

To generate the Auto-Zero function on the 432 Detector at the start of an injection, make the connections summarized in Table 2-11 and illustrated in Figure 2-8.

Table 2-9 Autosampler Chart Mark Cable Connections


AutosamplerTerminal

Marker In (+) Either Inject Start terminal of a pair

Marker In (–) Other Inject Start terminal of the same pair

Table 2-10 Autosampler Auto Zero Cable Connections


AutosamplerTerminal

Auto Zero (+) Either Inject Start terminal of a pair

Auto Zero (–) Other Inject Start terminal of the same pair


2

Before you can generate an Auto-Zero from an Alliance Separations Module, you must configure the Auto-Zero signal at the 432 Detector front panel. The default Auto-Zero signal is Low.

Figure 2-8 Alliance Separations Module Connections to the 432 DetectorAuto-Zero on Inject

Generating Chart Mark on Inject

To generate the chart mark function at the start of an injection, make the connections summarized in Table 2-12 and illustrated in Figure 2-9.

Table 2-11 Connections for Generating Auto-Zero on Inject

Alliance Separations Modules (B Inputs and Outputs)

432 Detector (A Inputs)

Pin 1 Inject Start Auto-Zero (+)

Pin 2 Inject Start Auto-Zero (–)

Inject Start +Inject Start –Ground

Stop Flow +Stop Flow –Hold Inject 1+Hold Inject 1 –Hold Inject 2 +Hold Inject 2 –Ground

Chart Out +Chart Out –

Waters AllianceB (Inputs and Outputs)

10 Auto-Zero -9 Auto-Zero +8 Ground7 Chart Mark -6 Chart Mark +5 Lamp On/Off -4 Lamp On/Off +3 Ground2 Inject Start -1 Inject Start +

Waters 432 DetectorA (Inputs)

+

–

+

–

+

–

+

–

INT

REC

LEAK

MARKERIN

MARKEROUT

AUTO ZERO

+–

+–

+–

+–

Int

Rec

Marker In

Auto Zero

Leak

Marker Out


2

Before you can generate a chart mark from an Alliance Separations Module, you must configure the chart mark signal at the front panel. The default chart mark signal is Low.

Figure 2-9 Alliance Separations Module Connections to the 432 DetectorChart Mark on Inject

2.5 Making Fluidic Connections

Fluid lines to a column and waste container connect to the front of the 432 Detector, as shown in Figure 2-10. To make these connections:

• Cut the tubing.

• Assemble compression fittings and ferrules.

• Connect the tubing to the detector.

Table 2-12 Connections for Generating Chart Mark on Inject

Alliance Separations Modules (B Inputs and Outputs)

432 Detector (A Inputs)

Pin 1 Inject Start Marker In (+)

Pin 2 Inject Start Marker In (–)

Inject Start +Inject Start –Ground

Stop Flow +Stop Flow –Hold Inject 1+Hold Inject 1 –Hold Inject 2 +Hold Inject 2 –Ground

Chart Out +Chart Out –

Waters AllianceB (Inputs and Outputs)

10 Auto-Zero -9 Auto-Zero +8 Ground7 Chart Mark -6 Chart Mark +5 Lamp On/Off -4 Lamp On/Off +3 Ground2 Inject Start -1 Inject Start +

Waters 432 DetectorA (Inputs)

+

–

+

–

+

–

+

–

INT

REC

LEAK

MARKERIN

MARKEROUT

AUTO ZERO

+–

+–

+–

+–

Int

Rec

Marker In

Auto Zero

Leak

Marker Out

Making Fluidic Connections 48

2

This section will guide you through each of these procedures.

Figure 2-10 Fluid Connections

Cutting Stainless Steel Tubing

You need the following tools to cut stainless steel tubing:

• A file with cutting edge

• Two cloth- or plastic-covered pliers

To cut the tubing:

1. Measure the length of 1/16-inch OD, 0.009-inch ID, stainless steel tubing you need to make the following connections:

• Column to the detector inlet

• Detector outlet to a suitable waste container

2. Use a file with a cutting edge to scribe the circumference of the tubing at the desired length.

3. Grasp the tubing on both sides of the scribe mark with cloth-covered pliers. Gently work the tubing back and forth until it separates.

4. File the ends smooth.

STOPAttention: Conductivity detection is sensitive to flow rate fluctuations. If you use a non-Waters pump or a Waters pump without the SILK microflow compensation algorithm, you must install the pulse dampener kit supplied in the Startup Kit for optimum performance. Refer to the installation procedure in this section.

In From Column IN OUT

Out To Waste (18 inches.

0.009-inch I.D.)


In from Column

Out to Waste (18 inches, 0.009-inch ID)


2

Cutting Polymeric Tubing

Waters chromatography systems are supplied with a tubing cutter (similar to the one in Figure 2-11) to facilitate cutting polymeric tubing. This section presents the recommended procedure for using the tubing cutter.

Note: To avoid bandspreading caused by angled cuts, always use a tubing cutter. Angled cuts leave unswept dead volumes at the connection junction due to the poor fit of the tubing against the connector or port.

To cut a length of polymeric tubing:

1. Estimate the length of tubing required to connect the components. Allow slack so that the tubing is not pulled tightly around sharp corners.

2. Insert the tubing into the cutter so that the tubing extending from the metal side is the length required. Use the proper hole to have a snug enough fit so that the tubing is not flexed by the blade when you cut it.

Figure 2-11 Cutting Polymeric Tubing

3. Press down on the razor blade to cut the tubing (Figure 2-11). Discard the excess tubing that extends from the clear side of the cutter.

4. Inspect the cut for burrs or scratches and for the perpendicularity of the cut.

Assembling Compression Fittings

To assemble each compression fitting:

1. Slide the compression screw over the tubing end, followed by the ferrule (Figure 2-12).

2. Mount the ferrule with its taper end facing the end of the tubing (Figure 2-12).


2
Figure 2-12 Ferrule and Compression Screw Assembly
Connecting to the 432 Detector

To make connections at the column outlet and detector inlet, and at the detector outlet:

1. Install a compression screw and then a ferrule on the length of 0.009-inch tubing from the column outlet. Use stainless steel fittings on stainless steel tubing and PEEK fittings on PEEK tubing.

Note: If you are using a column with 1/4–28 end fittings and there is a length of tubing with 1/4–28 fittings on each end, use the 1/4–28 to Z-detail adapter (included in the Startup Kit) to connect this tubing to the tubing that leads to the detector inlet.

The Waters IC-Pak C column comes supplied with a length of tubing that has a 1/4–28 fitting on one end (column outlet) and a Waters compression screw and ferrule on the other end (detector inlet).

2. Push the free end of the tubing as far as it will go into the IN fitting on the 432 Detector. While you hold it there, use a 5/16-inch open-end wrench to tighten the compression screw 3/4-turn past finger-tight.

Note: The 432 Detector and IC-Pak series of columns have very deep ferrules.

3. Remove the compression screw and tubing from the connection and verify that fluid can flow freely.

4. Reconnect the tubing to the IN fitting, making sure to push the tubing all the way into the fitting.

5. Install a ferrule on an 18-inch length of 0.009-inch tubing and connect it to the OUT connection on the 432 Detector. Use stainless steel fittings on stainless steel tubing and PEEK fittings on PEEK tubing.

6. Place the other end of the tube in a waste container. If you are using any Teflon tubing, attach it after the stainless steel or PEEK tubing.

CompressionScrew

Ferrule

0.009-inch I.D. Tubing(0.23 mm)

CompressionScrew

Ferrule

0.009-inch ID Tubing(0.23 mm)


2

Installing the Pulse Dampener

To achieve the best performance from the 432 Detector in a chromatographic system with a non-Waters pump, Breeze™ software, or Waters HPLC 515 Pump, you must install the pulse dampener kit supplied in the Startup Kit. The pulse dampener is not required if you are using a Waters 2695 Separations Module.

To install the pulse dampener between the pump and the injector:

1. Assemble the pulse dampener (Figure 2-13) using the instructions in the pulse dampener kit.

2. Connect the large-ID (0.020-inch) tubing to the pump outlet using a stainless steel compression screw and ferrule.

3. Connect the small-ID (0.009-inch) tubing to the injector inlet using a stainless steel compression screw and ferrule.

4. Disconnect the tubing from the injector inlet.

5. Pump ASTM Type I reagent water at £ 2 mL/min through the pulse dampener assembly until you see a constant stream exiting from the restrictor assembly outlet line.

6. Reconnect the tubing to the injector inlet.


2

Figure 2-13 Pulse Dampener

2.6 Passivating the System

Passivating the system removes potential contamination from the wetted surfaces of all system components. Perform passivation on a new system, and subsequently, whenever you suspect that contamination may have occurred. See Section 5.3, Troubleshooting, for help diagnosing performance problems.

Use this procedure for Waters hardware only. For other equipment, check with the manufacturer before you continue with this procedure.

STOPAttention: If you are installing the 432 Detector into an existing Waters system, replace the pump seals before you passivate. Use the new pump seals supplied in the Startup Kit and refer to the replacement procedure in the pump manual.

Low Pressure Filter Assembly

Restrictor Assembly

0.020-inch I.D. Tubing

0.009-inch I.D. Tubing

To InjectorUnionFrom Pum p

0.020-inch IDTubing

0.009-inch IDTubing

From Pump Union To Injector

Low PressureFilter Assembly

RestrictorAssembly


2

To passivate the system:

1. Replace the column with a union fitting.

2. If the system is not new, flush it thoroughly with ASTM Type I reagent water to remove any residual solvents or salts.

3. Connect the power cord to the 432 Detector and plug the other end into an AC power outlet. Push the 432 Detector power switch to turn on the instrument.

4. Prime the pump with 6 N nitric acid (HNO3) and run it at a flow rate of 1.2 mL/min for 20 minutes to passivate all the wetted parts of the detector. Press the Clear key to stop the overrange alarm.

5. Stop the pump.

6. Remove the inlet line from the nitric acid and place it in ASTM Type I reagent water.

7. Flush the system using one of the following methods:

• Prime and start the pump, then flush it with ASTM Type I reagent water at 1.2 mL/min until you observe a consistent reading of less than 20 µS (base range set to 50 µS).

• Flush the system overnight with 100% methanol at a reduced flow rate. By the next morning the system will be passivated and ready for use.

Note: If you are using a pump with seal-wash capability, skip step 8.

8. Use a syringe to flush the back of the pump seals and pistons by slowly running about 5 mL of water into the top hole in the baseplate of the pump heads. Place a tissue under the baseplates to absorb the water.

9. Set the pump flow rate to 0.0 mL/min. It is not necessary to turn off the 432 Detector unless it will be idle for an extended period (14 days).

For best results, always leave the power on to maintain cell temperature; it takes a minimum of 2 to 3 hours once the detector is turned on to equilibrate the flow cell at the selected operating temperature.

2.7 Verifying the Detector

This procedure is a guideline for verifying that the detector works correctly within its expected operational range. The detector is calibrated before shipping, and recalibration is not normally required.

Caution: To avoid chemical hazards, always wear safety glasses and gloves when you are using solvents.

Verifying the Detector 54

2

Verify the detector when any of these conditions apply:

• When you replace the flow cell

• To verify accuracy

• When you make adjustments

Calibration Procedure

Note: You need solution of 1 mM potassium chloride (KCl) to calibrate the detector.

Note: Waters suggests one of its Technical Service Representatives perform this procedure.

1. Turn on the 432 Detector and set the temperature control to 35 °C. Allow 2 to 3 hours for the temperature in the flow cell to equilibrate.

2. Set the base range to 200 µS.

3. Set the Filter Time Response to Fast.

4. Pump 1 mM KCl solution through the detector (without a column in place).

5. Verify that the front panel output is 147 µS ± 5 µS.


3

Chapter 3Operating the Detector

This chapter contains:

• A description of front panel controls and displays

• Procedures for starting up, shutting down, and long-term storage

• Recommended operating practices

3.1 Controls and Indicators

Figure 3-1 illustrates the controls and indicators on the front panel of the 432 Detector.

Figure 3-1 Front Panel

Remote Temp. Pol. ChartMark

7 8 9

4 5 6

1 2 3

0 . Clear

EnterShift

Resp. Bal.

BaseRange

Sens.Range

AutoBase

AutoZero

CONDUCT( S/cm)

BASE( S/cm/FS)

SENS

274 500 0.0005

ON

OFFIN OUT


Controls and Indicators 56

3

Power Switch

The power switch (located in the lower-right corner of the front panel) controls power to the 432 Detector. Upon startup, an initialization routine verifies the data in ROM memory, tests RAM memory function, and checks for any internal leakage or an eluent conductivity over-range condition.

Display

The display shows instrument status and parameter values in two 20-character lines of text. Upon startup, Waters 432 Self Check appears briefly. If any error conditions are detected during startup or normal operation, the appropriate error message is displayed.

The main screen shows the measured conductivity, as well as the base range and sensitivity settings. When you set an operating parameter, the display shows the selected or entered value.

Error Messages

A corresponding error message is displayed if one of the following conditions occurs:

• ROM/RAM error (checked during startup only)

Error: ROM/RAM

• Leakage detected

Error: Leak

• Temperature control failure

Error: Temp

• Over-range (above base range setting)

Error: Over Range

• Overflow (above 10,000 µS)

Error: Over Flow

Press the Clear key to clear an error alarm and message. For a continuing error condition, the error message remains after the audio alarm is cleared.

Keypad

Use the keypad to control the operation of the 432 Detector. Table 3-1 describes the function of each key.

Operating the Detector 57

3

Note: Three keys (Balance, Sensitivity Range, and the numeral 1) perform an alternate function when they are preceded by the Shift key.

Table 3-1 Key Descriptions

Key Function

Remote key: Toggles between local and remote operating modes. In remote mode, the light above the key is on and all other front panel controls are disabled.

Polarity key: Toggles the polarity of the signal to the external chart recorder and integrator. When positive polarity is selected, the light above the key is illuminated.

Base Range key: Sets the base sensitivity range of the 432 Detector to the appropriate value for the eluent being used. The base sensitivity is set to one of ten steps, from 10 µS (maximum gain) to 10,000 µS, using the Up and Down keys or the numeric keypad.

Sensitivity Range key: Sets the sensitivity range multiplier of the 432 Detector. The sensitivity range has twelve steps, from 0.0001 (maximum sensitivity) to 1.0 (available only with 100 µS multiplier setting), and is set using the Up and Down keys or the numeric keypad. The 10-mV full-scale recorder response is calculated by multiplying the Base Range by the Sensitivity Range to obtain a value of “x” µS / 10 mV FS. The recorder range is 1 to 0.0001 for the 100 µS setting and 0.1 to 0.0001 for the two lower settings.

Shift key then Sensitivity Range key: Sets the sensitivity range multi-plier of the integrator to 100, 50, or 10 µS using the Up and Down keys or the numeric keypad; the integrator output is 100, 50, or 10 µS/1 V, respectively.

Balance key: Manually sets the offset (%) of the signal to the external chart recorder. (Use the numeric keypad or Up and Down keys.)

Shift key then Balance key: Manually sets the offset (%) of the signal to the integrator. (Use the numeric keypad or Up and Down keys.)

Shift key after Balance key: Changes the polarity of the offset. Allow-able values are –100 to +100%.

Temperature key: Sets the temperature of the detection cell. Use the Up and Down keys or the numeric keypad to turn temperature control off (Setting 0) or select one of the following eight settings: 30, 35, 40, 45, 50, 55, 60, or 65 °C. The light above the key is illuminated when the temperature control is on.

Remote

Pol.

Base Range

Sens.Range

Bal.

Temp.


3

Response key: Sets the response time constant of the 432 Detector to optimize signal-to-noise ratio. Use the Up and Down keys or the numeric keypad to choose Setting 1 (Fast, 0.25 sec) for very narrow peaks, Setting 2 (Standard, 0.5 sec), or Setting 3 (Slow, 1.0 sec) to detect wider peaks. Setting 2 is used for most applications.

Auto Zero key: Automatically zeros the Recorder and Integrator signals to the specified Recorder Balance and Integrator Balance offsets, respectively.

Auto Base key: Automatically sets the base range of the 432 Detector to the appropriate value for the eluent being used. This is the next highest setting above the actual background conductivity of the eluent.

Shift key: Press the Shift key before, not along with, other keys to access additional functions and also to change polarity when you set balance offset values. When the Shift key is pressed, an asterisk (*) appears at the right side of the display; press Shift again to return to normal mode.

Shift key then Balance key: Displays the integrator balance offset value. When setting the balance offset, press Shift to change polarity.

Shift key then Sensitivity Range key: Displays integrator range value.

Shift key then 1 key: Displays the current, actual value of the chart recorder balance offset. Press Enter to return to the main screen.

Chart Mark key: When this key is pressed, a 1-second, 1-mV signal is sent to the Recorder terminals and a 1-second contact closure is sent to the Marker Out terminals.

Enter key: When you manually set offsets, sensitivity range, or base range, pressing Enter records the displayed value and returns the display to the main screen. The Enter key is also used to access the beep setting function.

Clear key: Erases a value input from the keypad. The Clear key is also used to clear an error alarm and message. For a continuing error condi-tion, the error message remains after the audio alarm is cleared.

Table 3-1 Key Descriptions (Continued)

Key Function

Resp.

AutoZero

AutoBase

ChartMark

Enter

Shift

Clear


3

Beep Function

You can set the 432 Detector to beep when a key is pressed and/or an error condition is detected.

Use the Clear key to stop an error alarm. For a continuing error condition, the error message remains after the beep is cleared.

To set the beep function, follow the procedure in Table 3-2.

Note: Since the void volume in many separations contains highly conductive counter-ions, the error alarm sounds upon each injection. See Table 3-2 to silence the beep-on-error alarm.

Up key: Increments the current parameter setting.

Down key: Decrements the current parameter setting.

Table 3-2 Setting the Beep Function

Keystroke Key Function

1 Enter Accesses the beep function parameters.

2 . (decimal point)

3 Enter

4 1 Turns on the beep-on-error function.

0 Turns off the beep-on-error function.

5 1 Turns on the beep-on-keystroke function.

0 Turns off the beep-on-keystroke function.

6 Enter Saves settings and returns to the main screen.

Table 3-1 Key Descriptions (Continued)

Key Function


3

3.2 Startup and Shutdown

Startup Procedure

Perform the following procedure to start the 432 Detector. Typically, this procedure is done at the beginning of each workday.

Note: This procedure assumes that the flow cell has stabilized at the selected temperature (minimum 2 to 3 hours). Standard practice is to leave the detector powered and with the temperature control on unless the instrument will be unused for several days.

Set the temperature at least 5 °C above the highest ambient temperature expected for the duration of the application.

1. Prime the pump with properly degassed eluent and set the flow rate to 1.2 mL/min or to the flow rate recommended for your particular column or application. Do not sparge eluents, since sparge gasses may contain ionic contaminants.

2. Set the response (time constant) to the desired setting by pressing the Response key. A standard setting (0.5 seconds) is preferred for most applications.

3. Set the base value by pressing the Auto Base key or by manually entering the base range that is the next highest setting above the eluent’s background conductivity.

4. Turn on the recorder/integrator and run the system until the baseline stabilizes.

5. Depending on whether you are using a recorder or an integrator, do one of the following actions:

• If you are using a 10-mV recorder connected to the Recorder terminals on the rear panel, select the desired sensitivity by pressing the Sensitivity Range key, then the appropriate Up or Down arrow key.

• If you are using an integrator connected to the Integrator terminals on the rear panel, select the desired sensitivity by pressing the Shift and Sensitivity Range keys, then the appropriate Up or Down arrow key.

6. Zero the recorder/integrator by pressing the Auto Zero key or have the Auto Zero terminals of the rear panel I/O terminal strip connected to your manual injector or autosampler.

The 432 Detector is now ready for operation.

Standby Setup

To eliminate the need to allow time for the flow cell temperature to equilibrate, leave the 432 Detector turned on at the end of the workday or workweek. Set the temperature control to the operating temperature and the pump flow rate to 0.01 to 0.1 mL/min (depending on the pump).


3

Long-Term Storage

If the 432 Detector is to be removed from a system for storage or if the system itself is to be stored for a long time, flush the detector/system with 100% water, then 100% HPLC-grade methanol. Leave the methanol in the system after shutdown. If you are removing the 432 Detector from the system, seal the inlet and outlet bulkheads with dead-end fittings or a loop of tubing.

3.3 Operating Recommendations

Observe the following recommendations for best detector performance.

Temperature Equilibration

The 432 Detector should be powered up and set at the desired operating temperature for two to three hours before use. Select a temperature at least 5 °C above the highest ambient temperature expected during the duration of the application. The detector is usually set at 35 °C, but it should be set higher if the ambient temperature will exceed 30 °C.

You may choose to leave the 432 Detector powered up overnight at a flow rate of 0.01– 0.1 mL/min (depending on the pump) to minimize the daily reequilibration time.

A drifting baseline is one indication that the temperature of the flow cell is not uniform across the flow cell or stable over time.

Base Range

The Base Range is normally set at the next setting above the background conductivity of the eluent. For example, if the conductivity of borate/gluconate eluent is 270 µS, set the Base Range to 500 µS.

Integrator Output

The Integrator output is not attenuated; signals should be below 1 V. Set the Integrator output to 10 µS/V for small signals or to 50 µS/V when you expect a signal greater than 10 µS. If you are using the 432 Detector with chemical suppression, set the integrator output to 100 µS/V.

Recorder Output

The Recorder output is attenuated and the Sensitivity Range should be adjusted to provide the appropriate output level.

Operating Recommendations 62

3

Polarity

Signal polarity depends on eluent conductivity. If necessary, press the Polarity key to obtain peaks rather than dips.

Eluent Handling

Replace your eluent reservoir filter regularly. When you analyze cations, use an all-plastic eluent reservoir filter. Filter and degas eluents to prolong column life, reduce pressure fluctuations, and decrease baseline noise. When you change eluents, flush the flow cell and associated tubing thoroughly with the new eluent.


4

Chapter 4Performing Ion Analysis

This chapter provides essential information about ion analysis techniques. Two representative columns serve as typical examples: the Waters IC-Pak A for anions and the IC Pak C M/D for cations. The following topics are discussed:

• Fundamental considerations

• Configuring the system

• Selecting and preparing eluents

• Preparing and injecting standards

Also refer to the manufacturer’s manual for the particular column you are using. A recommended source for more information about ion analysis in general is Ion Chromatography: Principles and Applications by Paul R. Haddad and Peter E. Jackson, Elsevier Science Publishing, New York, 1990.

4.1 Fundamental Considerations

To obtain full performance from the 432 Detector in chromatographic applications, observe the guidelines presented in this section regarding:

• Water

• Containers

• High-pH eluents

• Sample preparation

Water

Water purity (the absence of conductivity) is the most important consideration in ion analysis.

Note: Using water other than ASTM Type I reagent water will compromise the accuracy of your results.

Freshly drawn ASTM Type I reagent water, conforming to ASTM specification D1193, with total organic carbon <100 ppb is recommended. Sophisticated laboratory water systems that use a combination of reverse osmosis, mixed bed ion exchange, and carbon

Fundamental Considerations 64

4

adsorption cartridges produce ASTM Type I reagent water, and are recommended for ion chromatography applications. Do not use HPLC-grade water or distilled water.

Containers

Use plastic to contain all anion and cation samples, cation standards, and cation eluents. When you analyze trace level ions in water, polystyrene containers such as tissue culture flasks are recommended; polypropylene or polymethylpentene containers suit most other applications. Use polystyrene tissue culture flasks for long-term storage.

If your system operates on Breeze software or contains a 2695 Separations Module, use 4-mL polycarbonate vials to hold your samples and standards.

Preparing Containers for Low-Level Analysis

To prepare plastic containers for low-level analysis:

1. Soak all containers for 5 hours with a 1:1 solution of nitric acid (HNO3) and ASTM Type I reagent water.

2. Rinse with plenty of ASTM Type I reagent water. The containers are ready for analysis in the ppm range.

3. For analysis in the ppb range, fill each container completely with ASTM Type I reagent water and let soak overnight.

Certain applications that involve ppb level analysis may require container considerations beyond the scope of this manual. For further instructions on trace metal cleaning of plasticware, see “Selection and Cleaning of Plastic Containers for Storage of Trace Element Samples,” JR Moody and RM Lindstrom, Analytical Chemistry, v. 49, Dec 1977, pp. 2264-67, or contact the Waters Technical Services Department.

Cleaning Syringes

To avoid contamination, always rinse a syringe two to three times with ASTM Type I reagent water before you draw standards or samples for injection.

High-pH Eluents

High-pH eluents (such as hydroxide eluent) absorb atmospheric CO2, which slowly acidifies the eluent causing baseline drift and retention time changes. To minimize

STOPAttention: To avoid damage to the detector flow cell, do not allow the flow cell to dry out.

STOPAttention: Avoid glass containers (which tend to leach sodium cations) when you are analyzing for cations.

Performing Ion Analysis 65

4

carbonate absorption, connect a soda lime (Ascarite®) tube (Figure 4-1) to the eluent bottle as follows:

1. Insert a 3/4-inch (2-cm) piece of glass wool in one end of a polyethylene tube with end fittings. Attach the end fitting.

2. Fill the tube with soda lime (Ascarite) until it reaches 3/4 inches (2 cm) from the top.

3. Add another piece of glass wool to the other end of the tube and attach the end fitting.

4. Drill a hole in the cap of the reagent bottle. The hole should be large enough to accommodate the end fitting. Drill a second hole for the pump inlet line.

5. Pass the pump inlet line through the hole. Seal the hole with paraffin film.

6. Change the soda lime in the tube when it is exhausted.

Caution: To avoid chemical burns, wear gloves, lab coat, and eye glasses when you are handling soda lime.

Fundamental Considerations 66

4

Figure 4-1 Soda Lime Tube

Sample Preparation

Sample preparation is very important in ion analysis. Contact the Waters Technical Services Department, if you need assistance.

End Fittings

Glass Wool

Soda Lime

Polypropylene Tube

Reagent Bottle

Pump Inlet Line


4

As a general rule, to analyze a sample of completely unknown ionic concentration, initially prepare at least a 1:100 dilution and inject 100 µL. For best results, injections should contain a total anion concentration of no more than 300 ppm for the IC-Pak A column or a total cation concentration of no more than 10 ppm per ion for the IC-Pak C M/D column.

The sample volume (usually 100 µL) generally equilibrates to the pH of the eluent upon injection. However, for samples with pH values that differ greatly from that of the eluent (for example, strong acids and bases), bring the sample pH close to that of the eluent before you inject the sample, if possible.

Do not inject concentrated samples directly into the mobile phase. Direct injection may cause precipitation of the salts in the sample. Dissolve (or dilute) samples in an appropriate volume of the mobile phase first. If you must use other solvents, watch for precipitation upon injection into the eluent. Always filter samples before you use them.

Cationic samples that contain organic amines may exhibit hydrophobic interaction between the mobile phase and packing. You may use a water-miscible organic mobile phase, such as acetonitrile, as a modifier to reduce this. Pretreat the sample with a Sep-Pak

® C18 cartridge to remove hydrophobic compounds.

4.2 Configuring the System

Figure 4-2 shows a typical system configuration. Refer to Section 2.5, Making Fluidic Connections, for the procedures to cut tubing and assemble fittings.

Figure 4-2 System Configuration for Ion Analysis

TP01269

EluentReservoir

Pulse Dampener†

Pump

Injector

† Required for Waters pumps without SILK or non-W aters pumps

Guard Column Holder*

Column

Waters 432

Detector ToWaste

*Optional

Waters In-Line Degasser*

tRequired for non-Waters pumps or Waters pumps with Breeze software, suchas the HPLC 515

Configuring the System 68

4

Pulse Dampener

If your system uses a non-Waters pump or a Waters pump with Breeze software, such as the HPLC 515, use a pulse dampener (supplied in the Startup Kit) to achieve the best performance from the 432 Detector.

Install the pulse dampener between the pump and the injector, as described in “Installing the Pulse Dampener” on page 52.

4.3 Eluents for Ion Analysis

This section describes how to select, prepare, and use eluents for ion analysis.

General Guidelines

Observe the following guidelines when you prepare eluents for ion analysis:

• Use only ASTM Type I reagent water with total organic carbon <100 ppb.

• Use the highest purity salts and reagents available.

• A pH meter is recommended for checking the pH of eluents; care should be taken to avoid cross contamination. Adjust the pH with potassium hydroxide (KOH) or lithium hydroxide (LiOH). For eluents such as octane sulfonate, test an aliquot of the eluent with pH paper. Never immerse pH paper directly into a batch of eluent.

• Use the following formula to prepare eluents:

Formula Wt of Salt x Molarity = g/L Salt

Eluent Filtering and Degassing

The Waters Solvent Clarification Kit is recommended for eluent filtration and preliminary degassing. Durapore® 0.22-µm filters can be used for all ion chromatography eluents. Millipore 0.45-µm HATF filters may be used for aqueous eluents containing no organic modifier. For eluents containing organic modifier, use the Durapore filters.

After you install a new filter, pass 20 to 30 mL of eluent through the filter under vacuum. Turn off the vacuum, swirl the eluent throughout the flask and discard. Reattach the flask to the filter apparatus and filter the remaining eluent. As soon as filtration is complete,

STOPAttention: Never recirculate eluents. Ions from sample and standard injections progressively contaminate a recirculating eluent.

STOPAttention: To avoid contamination when you analyze for cations, minimize the time that the eluent is in contact with the glass filtration apparatus and transfer the eluent to a suitable pre-cleaned plastic container as soon as possible.


4

transfer the eluent to a precleaned plastic container, introducing the least possible amount of bubbles in the process.

The Waters In-line Degasser is recommended for continuous online degassing.

4.3.1 Preparing Anion Eluent

This section presents the procedure for the preparation of sodium borate/gluconate concentrate and eluent.

Consult the manufacturer’s manual for your column (IC-Pak Column and Guard Column Care and Use Manual included with Waters columns) for additional instructions on the selection and preparation of eluents.

A recommended source for more information about ion analysis in general is “Ion Chromatography: Principles and Applications,” by Paul R. Haddad and Peter E. Jackson, Elsevier Science Publishing, New York, 1990.

Preparing Lithium Borate/Gluconate Concentrate

To prepare sodium borate/gluconate concentrate, refer to Section C.1.13, Preparing Lithium Borate/Gluconate 50X Stock Concentrate and Section C.1.14, Preparing Lithium Borate/Gluconate Eluent.

4.3.2 Preparing Cation Eluent

To prepare 1 L of cation eluent, refer to Section C.2.1, Preparing Eluent.

4.4 Standards for Ion Analysis

This section describes how to prepare and inject ion standards.

Note: It is recommended to purchase certified 1000-ppm anion standards instead of preparing them manually. Certify all manual standards against National Institute of Science and Technology traceable standards.

Standard concentrations in this manual are defined in terms of mass. For example, 1 mg of sample per liter of water equals a 1 ppm concentration, since 1 L of water has a nominal mass of 1 kg (0.997 kg at 25 °C).

1 part per thousand = 1 mg/mL = 1 g/L = 1000 ppm

1 part per million (ppm) = 1 µg/mL = 1 mg/L = 1000 ppb

1 part per billion (ppb) = 1 ng/mL = 1 µg/L = 1000 ppt

1 part per trillion (ppt) = 1 pg/mL = 1 ng/L

Standards for Ion Analysis 70

4

Storing Standards

For accurate quantitative results, do not store standards beyond the approximate periods listed in Table 4-1. Be aware that shelf-life depends on many factors and may be significantly shorter than shown here.

Cation standards must be stored in properly prepared plasticware. See “Containers” on page 65.

4.4.1 Preparing Anion Standards

This section presents the procedure for preparing a 7-anion standard. If a simpler standard suffices, follow the procedure, but select only three or four salts, such as sodium chloride, sodium nitrate, and sodium sulfate.

Always use salts of at least reagent-grade purity. If you require quantitative results or you use hygroscopic salts, dry the salts overnight at 80 °C before you make solutions. Store the dried salts in a desiccator.

Preparing a 7-Anion Standard

To prepare a 7-anion standard:

1. Weigh out the amounts of dry salts shown in Table 4-2 or use the following formula to calculate the amount for a salt not listed:

(Mol. Wt. Salt / Mol. Wt. Cation) x 0.1 = g Salt

Table 4-1 Shelf-Life of Standards

Standard Shelf-Life

Carbonate, ppm 1 day

Chloride, ppm 3 weeks

All, ppb 1 day

Nitrite and carbonate concentrates 1 week

All other anion concentrates 1 to 2 months

Cation standards 1 month

Cation concentrates 6 months


4

2. Place each salt in a separate plastic100-mL volumetric flask and dilute to the mark with ASTM Type I reagent water. Each concentrate contains 1000 ppm of the anion.

3. Combine the amounts listed in Table 4-3 in a 100-mL volumetric flask with ASTM Type I reagent water.

4.4.2 Injecting Anion Standards

Required Materials

To inject a standard, obtain the following materials:

• Borate/gluconate eluent – Refer to Section C.1.13, Preparing Lithium Borate/Gluconate 50X Stock Concentrate and Section C.1.14, Preparing Lithium Borate/Gluconate Eluent.

Table 4-2 Salts for Anion Standard Concentrates

Salt (Anion) Weight (mg)

Sodium fluoride (F–) 221.0

Sodium chloride (Cl–) 164.9

Sodium nitrite (NO2–) 150.0

Potassium bromide (Br–) 148.9

Sodium nitrate (NO3–) 137.1

Potassium phosphate, monobasic (HPO4

2–)141.8

Sodium sulfate (SO42–) 147.9

Table 4-3 Anion Concentrate Dilutions

AnionAmount

(µL)Final Concentration

(ppm)

Fluoride 100 µL 1 ppm

Chloride 200 µL 2 ppm

Nitrite 400 µL 4 ppm

Bromide 400 µL 4 ppm

Nitrate 400 µL 4 ppm

Phosphate 600 µL 6 ppm

Sulfate 400 µL 4 ppm


4

• 1-cc disposable plastic syringe – Pharmaseal® Stylex® disposable syringe with a Luer Slip® tip, or equivalent.

• Autoinjector or manual injector with 100-µL loop – Ion chromatography commonly uses a 100-µL injection volume. When you use a fixed loop, overfill a minimum of three times.

Injecting the Standard

To inject the standard:

1. Set up the 432 Detector as follows:

• Base Sensitivity = 500 µS

• Integrator Sensitivity = 10 µS/V

• Recorder Sensitivity = 0.01 (strip chart)

• Response = STD (0.5 seconds)

• Temperature = 35 °C

• Polarity = +

2. Equilibrate the 432 Detector as described in “Startup Procedure” on page 61.

3. Rinse a 1-cc disposable plastic syringe two or three times with ASTM Type I reagent water, then load the standard.

4. Place the syringe tip into the sample loading port and overfill the 100 µL loop at least three times (that is, 300 µL).

5. Inject the sample.

Figure 4-3 shows a representative chromatogram of the 7-anion standard run on an IC-Pak A (4.6 mm x 5.0 cm) column with borate/gluconate eluent at 1.2 mL/min flow rate. The separation of the standard typically takes 12 to 15 minutes with this setup.


4

Figure 4-3 Chromatogram of a 7-Anion Standard

4.4.3 Preparing Cation Standards

This section presents the procedure for preparing an 8-cation standard. If a simpler standard suffices, follow this procedure selecting only those salts that you want in the standard. For accurate quantitative results, use only properly prepared plasticware and do not store standards beyond the recommended shelf-lives listed in Table 4-1.

Preparing Cation Standard Concentrates

Note: It is recommended that you use certified 1000-ppm cation standards not prepared in acid with this method.

To prepare concentrated stock solutions for an 8-cation standard (prepare fewer types of cations, if a simpler standard suffices):

1. Weigh out the amounts of dry salts shown in Table 4-4 or use the following formula to calculate the amount for a salt not listed.


4

(Mol. Wt. Salt / Mol. Wt. Cation) = g Salt

If you choose to use other salts, be sure to avoid any combinations that will form a precipitate.

2. Place each salt in a separate plastic1-L volumetric flask and dilute to the mark with reagent-grade water. Each concentrate contains 1000 ppm of the cation.

Preparing an 8-Cation Standard

To prepare 1 liter of 8-cation standard:

1. Add the volume of stock (concentrate) standard listed in Table 4-5 to a plastic 1-L volumetric flask.

2. Fill the flask to the mark with ASTM Type I reagent water.

Table 4-4 Salts for Cation Standard Concentrates

Salt (Cation) Weight (g)

Lithium hydroxide monohydrate (Li+) 6.0476

Sodium chloride (Na+) 2.5421

Ammonium chloride (NH4+) 2.9640

Potassium chloride (K+) 1.9067

Magnesium nitrate hexahydrate (Mg2+) 10.5466

Calcium nitrate tetrahydrate (Ca2+) 5.8919

Strontium nitrate tetrahydrate (Sr2+) 3.2377

Barium chloride dihydrate (Ba2+) 1.7786

Table 4-5 Cation Concentrate Dilutions

Cation Amount (mL)Final Concentration

(ppm)

Lithium 0.25 0.25

Sodium 1.00 1.00

Ammonium 1.00 1.00

Potassium 3.00 3.00

Magnesium 2.00 2.00

Calcium 3.00 3.00

Strontium 5.00 5.00

Barium 5.00 5.00


4

4.4.4 Injecting Cation Standards

Required Materials

To inject the standard, obtain the following materials:

• 0.1 mM EDTA/ 3 mM HNO3 cation eluent – Refer to Section 4.3.2, Preparing Cation Eluent.

• 1-cc disposable plastic syringe – Pharmaseal® Stylex® disposable syringe with a Luer Slip® tip, or equivalent.

• Injector or autosampler with a 100-µL loop – Ion chromatography commonly uses a 100-µL injection volume. When you use a fixed loop, overfill a minimum of three times.

Injecting the Standard

Note: You can substitute the method described in Section C.2, Alkali and Alkaline Earth Cations, Ammonium, and Amines, for the following procedure.

Use this procedure to inject the standard.

1. Set up the 432 Detector as follows:

• Base Sensitivity = 2000 µS

• Integrator Sensitivity = 50 µS/V

• Recorder Sensitivity = 0.01 (strip chart)

• Response = STD (0.5 seconds)

• Temperature = 35 °C

• Polarity = – (negative)

2. Equilibrate the 432 Detector as described in “Startup Procedure” on page 61.

3. Rinse a 1-cc disposable plastic syringe two or three times with ASTM Type I reagent water, then load the standard.

4. Place the syringe tip into the sample loading port and overfill the 100-µL loop at least three times (that is, 300 µL).

5. Inject the sample.

Figure 4-4 shows a representative chromatogram of an 8-cation standard run on an IC-Pak C M/D column with 0.1 mM EDTA/3 mM HNO3 eluent at 1.0 mL/min flow rate. The separation of the standard typically takes 20 to 25 minutes with this setup.


4

Figure 4-4 Chromatogram of an 8-Cation Standard


5

Chapter 5Maintenance

This chapter contains information about maintaining the 432 Detector and troubleshooting charts to help you isolate and correct problems.

5.1 Routine Maintenance

This section contains information designed to help you maintain the 432 Detector. Routine maintenance for the 432 Detector includes:

• Replacing the fuse

• Calibrating the detector

• Maintaining the flow cell

Waters service specialists provide maintenance for the 432 Detector on a corrective, as required, basis. Contact the Waters Technical Services Department if you have questions regarding the repair or performance of your instrument.

Follow these suggestions to help you maintain the 432 Detector:

• Stock the recommended spare parts listed in Appendix B to reduce downtime. Contact the Waters Service Department for assistance.

• Record the initial installation date and serial number of your instrument in Appendix B for easy reference.

• Keep a file of typical chromatograms for comparison when you suspect problems.

5.1.1 Replacing the Fuse

To change the operating voltage fuse:

1. Turn off the front panel power switch and remove the power cord from its connector on the rear panel of the detector.

Caution: To avoid the possibility of electric shock, power off the detector and disconnect the power cord before you service the instrument.

Caution: To avoid the possibility of electric shock, turn off the front panel power switch, and unplug the power cord from the rear panel.

Routine Maintenance 78

5

2. Pry open the power connector cover with a screwdriver.

3. To change the AC power fuses, pull out each fuse holder as though opening a drawer. Spare fuses are included in the System Startup Kit. For ordering information, see Appendix B, Spare Parts.

4. Table 2-2 on page 34 lists the operating voltage fuses (for use in either North America or Europe).

5. Install the correct fuse in the holder and slide it back into place (Figure 5-1). The arrow on each fuse holder points up when in the correct position.

Figure 5-1 Installing Operating Voltage Fuses

6. Close the power connector cover. Then plug the power cord into its connector on the rear panel of the detector.

5.1.2 Maintaining the Flow Cell

Maintenance for the 432 Detector consists of ensuring the flow cell is free of foreign material. Foreign material in the flow cell may cause baseline drift, cycling, or noise.

To clean the cell:

1. Flush the system with ASTM Type I reagent water.

2. Flush the system with 20 mL of 6 N nitric acid (HNO3).

3. Flush the system again with ASTM Type I reagent water. Do not reconnect the column until the eluent has returned to about pH 7.

STOPAttention: To avoid damaging the column, remove it before you flush the system. Do not reconnect the column until the eluent has returned to approximately pH 7.

Maintenance 79

5

Refer to Appendix B, Spare Parts, to order a replacement flow cell. The following tools are required to replace the flow cell:

• Phillips-head screwdriver

• 5/16-inch open-end wrench

• Knife or flat-blade screwdriver

1. Unplug the 432 Detector from the power source, and completely disconnect all electrical cables and fluid connections.

2. Remove the 432 Detector cover (four Phillips-head screws, two on each side).

3. Remove the two pins and pin holders that hold the cell block cover in place (see Figure 5-2). Use a knife or flat-blade screwdriver to gently pry the pins and holders out.

4. Pull off the cover of the flow cell unit and remove the top layer of insulation.

5. Remove the four Phillips-head screws from the upper plate of the cell block, and remove the plate. Note the orientation of the plate: a notch is cut into the underside to clear one of the components within the cell block.

6. Carefully disconnect the inlet and outlet fittings from the flow cell.

7. Remove the two Phillips-head screws from the flow cell mounting bracket.

8. Unplug the flow cell cable connector from its socket in the cell block.

9. Remove the flow cell assembly.

10. Install the new flow cell by following steps 2 through 9 in reverse order. Be sure to orient the upper plate of the cell block properly before you install the four screws.

Caution: To avoid electrical hazards, always unplug the power cord before you perform any of the following replacement procedures.

Routine Maintenance 80

5
Figure 5-2 Flow Cell Assembly
Pin

Upper plate screws

Upper plate of cell block

Insulation

Cell block cover

Pin

ConnectorFlow cell

Cell mounting bracket screws

Cell mountingbracket

Cell block

Pin holder

Pin holder

Maintenance 81

5

5.2 Cleaning the Detector Exterior

To clean the outside of the 432 Detector, use only a soft lint-free paper or cloth dampened with mild soap and water.

5.3 Troubleshooting

This section contains troubleshooting charts to help you isolate and correct problems with the 432 Detector.

Keep in mind that the source of apparent detector problems may lie within the chromatography or hardware of your system. The Waters Guide to Successful Operation of Your LC System contains detailed chromatographic troubleshooting tables. (Contact your nearest Waters office for information on how to get a copy.) If you cannot correct a problem, contact the Waters Technical Services Department for assistance.

When You Call Waters Service

To expedite your request for service, have the following information available when you call Waters regarding a 432 Detector problem:

• Symptom

• Type of column

• Eluent(s)

• Flow rate

• Operating pressure

• Base Range setting

• Integrator Sensitivity setting

• Recorder Sensitivity setting

• Type of injector (automatic or manual)

• Type of data integrator

Detector Does Not Turn On

If your detector is completely inoperative (for example, the lights do not illuminate and the display remains completely blank when the unit is turned on), the fuse may require replacement. Refer to Section 5.1.1, Replacing the Fuse.

Cleaning the Detector Exterior 82

5

Startup Diagnostics

The 432 Detector performs startup diagnostics that check the internal memory (both RAM and ROM), and the associated processing circuitry.

Power Supply

The following factors can adversely affect the operation of the 432 Detector:

• Power surges

• Line spikes

• Transient energy sources

Be sure that the electrical supply used for the 432 Detector is properly grounded and free from any of these conditions.

Error Messages

The error messages displayed by the 432 Detector are listed below along with the recommended action for each:

• Error: ROM/RAMROM/RAM error (checked during startup only)Call Waters service.

• Error: LeakLeakage detectedCheck flow cell and associated plumbing connections.

• Error: TempTemperature control failureCall Waters service.

• Error: Over RangeBase over-range conditionSet Base Range to the next setting above the background conductivity of the eluent.

• Error: Over FlowConductivity overflow (above 10,000 µS)Dilute eluent to remain within measurable range.

Press the Clear key to clear an error alarm and message. For a continuing error condition, the error message remains after the audio alarm is cleared.

Troubleshooting Procedure

As soon as you realize that a problem may exist:

1. Visually examine the integrity of the electrical and fluid connections as you verify proper system configuration and installation.

Maintenance 83

5

2. If the results of previous runs are available, compare the current system operation with the system operation before you identified the problem.

For example, if your system usually runs at a certain pressure with a certain method:

• Is the system pressure in the same range, or is it drastically higher (possibly caused by a blocked line) or lower (possibly caused by a leak)?

• Are pressure fluctuations in the same range as during normal operation?

3. Isolate the parameter that varies from normal operation. The parameters to observe include:

• Baseline noise

• Peak retention time

• Peak resolution

• Qualitative/quantitative chromatographic results

• System pressure

Evaluate the parameters in the order presented above to rule out simple causes of the problem.

4. Use Table 5-1 to determine corrective actions for the problems that you identify.

Removing Bubbles

Bubbles in the flow cell are evident when the noise is equal to or greater than 2 µS. Use this method to remove bubbles.

1. Disconnect the tubing from the inlet and outlet of the 432 Detector.

2. Attach a 1-mL tuberculin syringe to a priming syringe cannula which is screwed into the inlet of the detector.

3. Flush four times with 1-mL portions of ASTM Type I reagent water.

4. Flush four times with 1-mL portions of HPLC-grade methanol.

5. Flush four times with 1-mL portions of ASTM Type I reagent water.

6. Reattach the tubing from the 432 Detector outlet to a waste receptacle (18-inch length of 0.009-inch ID stainless steel).

7. Start eluent flowing through the system at a flow rate of at least 1 mL/min.

8. With the eluent flowing, reattach the detector inlet tubing to the column.

9. Allow a few minutes for temperature reequilibration, then check the noise level. If it is not reduced, repeat steps 1 through 4, then proceed to steps 10 through 13.

10. Attach a dead-end fitting to the 432 Detector outlet.

11. Remove the priming syringe cannula and attach a dead-end fitting to the 432 Detector inlet.

Troubleshooting 84

5

12. Allow the detector to stand overnight (>12 hours) with temperature on and with methanol in the flow cell.

13. Repeat steps 5 through 9.

Table 5-1 Troubleshooting Guide

Symptom Possible Cause Solution

Noisy baseline Pulse dampener not installed See “Installing the Pulse Dampener” on page 52.

Pulsing pump Check the pump; see the pump manual.

Bubbles in flow cell Remove bubbles and degas the solvent.

Voltage fluctuation Use the voltage regulator.

Spikes on baseline Dirty flow cell Clean the cell.

Flow cell leak Check flow cell fittings and tighten. If leak continues, replace the flow cell.


Irregular noise on baseline

Temperature changes in room Control ambient tempera-ture, locate drafts, and insulate tubing and column, if necessary.

Cell temperature set lower than ambient

Set the cell temperature to a minimum of 5 °C above ambient.

Defective column Replace the column.

Excessive baseline drift

Unstable temperature control Make sure the temperature control is turned on.

Defective cell heater Call Waters service.

Temperature changes in room Control ambient tempera-ture, locate drafts, and insulate tubing and column, if necessary.

Cell temperature set lower than ambient

Set the cell temperature to a minimum of 5 °C above ambient.

Maintenance 85

5


Solvent changeover Wait until baseline stabilizes (purge autosampler a few times).

Flow cell leak Check flow cell fittings and tighten. If leak continues, replace the flow cell.

Detector cannot be zeroed

Solvent changeover Wait until the baseline stabilizes.


Continuous noise at high sensitivity (<1µS)

Pump crossover noise Install a high-sensitivity noise filter on the pump.

Table 5-1 Troubleshooting Guide (Continued)

Symptom Possible Cause Solution

Troubleshooting 86

A
Appendix ASpecifications
This appendix includes information on:

• Operational specifications

• Mechanical specifications

• Environmental specifications

• Electrical specifications

• Communications

Table A-1 Operational Specifications

Condition Specification

Drift Less than 0.05 µS/hr/°C (ambient)Base: 200 µSSensitivity: 0.005Eluent: 1 mM KCI

Noise Less than 0.005 µS/cmBase: 200 µSSensitivity: 0.005Eluent: 1 mM KCI

Temperature control Front-panel selectable: OFF, 30, 35, 40, 45, 50, 55, 60, 65 °CPerformance: 0.5 °C/hr

Response times Fast: 0.25 secStandard: 0.5 secSlow: 1.0 sec

Table A-2 Mechanical Specifications


Cell volume 0.6 µL

Wetted materials 316 stainless steel, PTFE, and PCTFE

Specifications 87

A
Operating pressure 70 psi maximum
Height 9.4 inches (23.8 cm)

Length 21 inches (53.3 cm)

Width 11.5 inches (29.2 cm)

Weight 17.7 pounds (8 kg)

Table A-3 Environmental Specifications


Operating temperature range 4 to 35 °C(40 to 95 °F)

Operating humidity 20 to 80% RH, noncondensing

Table A-4 Electrical Specifications


Protection classa

a. Protection Class I – The insulating scheme used in the instrument to protect you from electrical shock. Class I identifies a single level of insulation between live parts (wires) and exposed conductive parts (metal panels), in which the exposed conductive parts are connected to a grounding system. In turn, this grounding system is connected to the third pin (ground pin) on the electrical power cord plug.

Class I

Over-voltage categoryb II

Pollution degreec 2

Moisture protectiond Normal (IPXO)

Line voltages (grounded

AC), nominal

100/120 VAC220/240 VAC

Line frequency ranges 50 Hz: ±2 Hz60 Hz: ±2 Hz

100/120 VAC fuse rating T2 A (20 mm)

220/240 VAC fuse rating T1 A (20 mm)

Current (Max) 0.6 A

Table A-2 Mechanical Specifications (Continued)


Specifications 88

A

b. Over Voltage Category II – Pertains to instruments that receive their electrical power from a local level such as an electrical wall outlet.

c. Pollution Degree 2 – A measure of pollution on electrical circuits, which may produce a reduction of dielectric strength or surface resistivity. Degree 2 refers to normally only nonconductive pollution. Occasionally, however, a temporary conductivity caused by condensation must be expected.

d. Moisture Protection – Normal (IPXO) – IPXO means that there is NO Ingress Protection against any type of dripping or sprayed water. The X is a placeholder to identify protection against dust, if applicable.

Table A-5 Communications

Signal Specification

Recorder output 0 to 10 mV

Integrator output 10, 50, 100 µS/1V FS

Marker output Isolated contact output

Controller bus IEEE-488, PowerLine™

Specifications 89

Spare Parts 90

B

Appendix BSpare Parts

The parts listed in Table B-1 are spare parts recommended for installation by you, the customer. Any parts that are not listed may require installation by a trained service representative. Order a supply of the parts listed in Table B-1 to keep in stock for use as needed.

Note: The flow cell (part number 043069) is considered a replacement part. Order the flow cell only when it is needed for replacement in the Waters 432 Detector.

Fill in the information below for easy reference when you order parts or request service.

Installation Date: _____________

Serial Number: ____________

Table B-1 Spare Parts

Item Quantity Part Number

Fuse, Time Delay, 1A, 250V, IEC 2 WAT165-11

Fuse, Time Delay, 2A, 5x20 mm T 2 WAT165-14

Fitting kit 1 WAT025604

Pump Seal Replacement kit 2 WAT022934

Union 1 WAT097332

C

Appendix CIon Chromatography Methods

This appendix provides information about:

• General-purpose anion analysis using conductivity and UV detection

• Alkali and alkaline earth cations, ammonium, and amines

C.1 General-Purpose Anion Analysis Using Conductivity and UV Detection

Table C-1 Required Instrumentation

Instrument Part Number

Alliance, 2695 Separations Module or Breeze (with column heater, seal wash, and degasser)

N/A

432 Conductivity Detector 043061

busSAT/IN Module 200415

Empower/Breeze data processing Contact Waters

UV Detector (optional) Contact Waters

Ion Chromatography Methods 91

C
Figure C-1 Common Anion Standards
Table C-1 Analysis Conditions

Condition Value

Column IC-Pak A/HR (part number 026765)

Eluent Borate/gluconate containing 12% AcCN

Back conductivity 240 ±20 µS

Degas Continuous

Flow rate 1 mL/min.

Backpressure 1200 ±200 psi

Temperature 30 °C for column heater, 35 °C for detector

Injection 100 µL

Needle wash 12% AcCN in DI water

Detection Direct conductivity

Base range 500

Attenuation 50 µS/Volt unattenuated

Polarity Positive


C

C.1.1 Preparing Eluent1. Add 20 mL of lithium borate/gluconate concentrate and 120 mL of HPLC-grade

acetonitrile (AcCN) into a 1-liter volumetric flask (see Section C.1.13, Preparing Lithium Borate/Gluconate 50X Stock Concentrate, for concentrate preparation).

2. Dilute to volume with DI water.

3. Ensure the natural pH is 8.2 ±0.1.

4. Vacuum degas through a 0.45-µm aqueous and solvent-compatible membrane filter.

5. Store in a glass or plastic container at ambient temperature. Discard after 1 month.

C.1.2 Preparing Standards

It is recommended that you use certified 1000-ppm anion standards with this method. If unavailable, see Section C.2.7, Preparing Stock Reagent, for uncertified standard preparation.

Prepare at least three mixed analyte standards within the expected range of sample analyte concentration. This method is linear from 0.1 to 100 ppm. After you validate the multi-point calibration curve, a single-point calibration curve within the expected analyte concentration range is appropriate for recalibration.

C.1.3 Preparing a Sample1. Determine the expected range of analyte concentration and other anionic

component in the sample matrix. The major analyte should be less than 100 ppm for best results.

2. Dilute the sample with DI water, if necessary.

3. If the sample contains high amounts of neutral organics or is highly colored, pass the diluted sample through a C18 Sep-Pak cartridge. Anions pass through unretained, but there can be a loss of fluoride recovery.

4. Filter samples containing suspended solids through a 0.45-µm aqueous-compatible disk before injection. Failure to filter solids can increase column backpressure.

Note: For best results, ensure sample pH is between 3 and 11.

Samples treated with a sample preparation disk in the H+ form, used to remove cations and neutralize high pH, will yield chromatograms similar to suppressed conductivity chromatograms.


C

C.1.4 Empower Data Processing Method

Table C-2 IC Processing Method Using Peak Apex for Retention Time

Process Values

Integration Peak Width = 30.0

Minimum Area = 3000

Inhibit Intg. = 0 to 2 min.

Threshold = 10 to 25

Minimum Height = 150

Calibration Averaging = None

Update RT = Never

Peak Match = Closest

Quant By = Peak Area

Fit Type = Linear for multi-point calibration, Linear Through Zero for single-point calibration

Report Analyte Name

Analyte Retention Time

Peak Area

Amounts


C

C.1.5 Method Validation

This validation design is abstracted from ASTM/EPA validation. It has been used to validate all anion analysis methods. Many of the methods using this validation design are linear above 50 ppm.

C.1.6 Method Linearity

Figure C-2 Calibration Curves for Chloride, Fluoride, and Bromide

Table C-3 Method Validation

Individual Youden Pair Standard, in ppm

An

alyt

e A

nio

n

1 2 3 4 5 6 7 8

Cl 0.7 2.0 3.0 15.0 40.0 20.0 50.0 0.5

Br 2.0 3.0 15.0 40.0 20.0 50.0 0.7 0.5

NO2 3.0 40.0 20.0 15.0 50.0 0.5 2.0 0.7

SO4 40.0 50.0 0.5 0.7 2.0 3.0 15.0 20.0

NO3 15.0 20.0 40.0 50.0 0.5 0.7 2.0 3.0

F 2.0 0.7 0.5 3.0 10.0 7.0 20.0 25.0

PO4 50.0 40.0 20.0 0.5 3.0 2.0 0.7 15.0

Cl r2 = 0.9999

F r2 = 0.9986

Br r2 = 0.9999


C

Figure C-3 Calibration Curves for Nitrite and Nitrate

Figure C-4 Calibration Curves for Sulfate and Phosphate

NO2 r2 = 0.9999

NO3 r2 = 0.9992

SO4 r2 = 0.9999

PO4 r2 = 0.9992


C

C.1.7 Quantitation Precision

Quantitation Precision is the percent RSD of analyte peak area at each concentration. Data is based on seven replicate injections of the validation standards.

C.1.8 Method Detection Limits

Figure C-5 100-µL Injection

Table C-4 Quantitation Precision

Analyte F CI NO2 Br NO3 PO4 SO4

pp

m C

on

cen

trat

ion

0.5 0.95 1.11 3.44 5.17 0.32 12.98 7.62

0.7 0.67 1.64 0.78 1.73 0.75 9.29 3.90

2 0.17 0.18 0.56 1.14 0.91 2.91 1.07

3 0.43 0.17 0.20 0.67 0.19 3.49 0.64

15 0.44 0.05 0.28 0.11 0.16 0.50 0.32

20 0.45 0.04 0.05 0.30 0.06 0.52 0.25

40 0.05 0.04 0.03 0.08 0.37 0.26

50 0.13 0.02 0.26 0.03 1.56 0.16

100-PPB Standards


C

Based on this representative chromatogram using a 100-µL injection, the estimated detection limits, as ppb, at three times signal to noise (S/N) are as follows:

• Fluoride = 50

• Chloride = 25

• Nitrite = 50

• Bromide = 75

• Nitrate = 75

• Phosphate = 125

• Sulfate = 75

Quantitation below these detection limits is not advised. You can obtain lower detection limits using a 250-µL injection.

C.1.9 Quantitation Accuracy

The Certified Performance Evaluation Standards were diluted 1:100 with DI water. Amounts are based on a multi-point calibration curve prepared from certified standards.

Table C-5 Quantitation Accuracy

Analyte F CI NO2 NO3 PO4 SO4

Performance Evaluation Standard

True Value in ppm

2.69 43.00 1.77 15.37 6.29 37.20

Official Anion Methods Wet

Chem & IC

Measured Mean

2.75 43.30 1.77 15.42 6.38 37.00

Measured Std Dev

0.26 3.09 0.07 1.15 0.21 2.24

IC UsingAlliance IC

Pak A/HR and B/G Eluent

Ave IC n=3 2.63±0.05

43.87±0.09

1.93±0.01

15.04±0.06

6.47±0.09

37.03±0.12

IC/Mean 0.956 1.013 1.090 0.975 1.014 1.001

IC/True Value

0.978 1.020 1.090 0.979 1.029 0.995


C

C.1.10 Analyte Recovery

The Certified Performance Evaluation Standards were diluted 1:100 with typical drinking water. Amounts are based on a multi-point calibration.

Table C-6 Analyte Recovery

Analyte F CI NO2 NO3 PO4 SO4

Milford Drinking Water

n=3, as ppm

Not detected

25.82±0.04

Not detected

0.23±0.002

Not detected

8.300.02

%RSD 0.16 0.92 0.27

Performance Evaluation Std

2.69 43.00 1.77 15.37 6.29 37.20

MDW + PES n=3; as ppm

2.46±0.04

69.64±0.08

1.82±0.004

15.52±0.02

5.35±0.05

46.46±0.17

%RSD 1.51% 0.11% 0.21% 0.10% 0.92% 0.37%

% Recovery 91.4% 102.5% 102.8% 99.5% 85.1% 102.8%


C

C.1.11 Example of Use

Figure C-6 Typical Drinking Water, No Dilution Required

C.1.12 Using Direct UV Detection

Many anions are UV active in the range of 205 to 214 nm, such as NO2, Br, and NO3, and the use of direct UV detection provides a degree of detector selectivity. Figure C-7 shows the chromatogram of the anion standard that demonstrates this selectivity. Generally, the lower the wavelength of detection, the greater is the response, as seen with the difference between 205- and 214-nm chromatograms. However, the borate/gluconate eluent has some UV absorption which causes negatives peaks at the retention time of the UV transparent anion, such as F, Cl, PO4, and SO4, if present.


C
Figure C-7 Direct UV Detection
Direct UV detection is five times more responsive for nitrite and nitrate than is conductivity detection and therefore provides lower detection limits. The chromatogram in Figure C-8 of a 100-ppb anion standard demonstrates the improved sensitivity.

Figure C-8 100-ppb Anion Standard

Waters 996 Photodiode Array Detector


C

The borate/gluconate eluent has some UV absorption. Use of eluents that are UV transparent, such as hydroxide and carbonate/bicarbonate, provide lower detection limits.

C.1.13 Preparing Lithium Borate/Gluconate 50X Stock Concentrate1. Using a 60-mL plastic syringe, add approximately 25 g of BioRad AG-50W-X12

strong cation exchange resin in the hydrogen form, or equivalent. Wash the resin with five 20-mL portions of DI water to remove any ionic impurities from the resin. Discard the washings.

2. Dissolve 9.06 g of sodium gluconate in approximately 20-mL of DI water. After dissolution, transfer this solution into the 60-mL syringe with resin. Slowly pass this solution into a 1-liter volumetric flask. Wash the resin with five 20-mL portions of DI water, then add the washing to the volumetric flask. Discard the syringe and resin.

An alternative is to use commercially available 50% gluconic acid. However, it comes as a brown solution that, when diluted, gives a yellow tint to the eluent that can affect long-term performance. You can remove the brown color by passing 5 mL of 50% gluconic acid through a C18 Sep-Pak cartridge. This requires three Sep-Pak cartridges. Use 13.2 mL of 50% gluconic acid for the eluent concentrate.

3. Adjust the volume in the flask to approximately 500 mL with DI water and use a stirring bar. Add 7.2 g of lithium hydroxide monohydrate and 25.5 g of boric acid. With the aid of a magnetic stirrer, mix until all reagents are dissolved.

4. Add 94 mL of 95% glycerol and mix. Remove the stirring bar and fill to the mark with DI water.

5. Store this lithium borate/gluconate concentrate in a plastic container at ambient temperature for up to 6 months. You can store it at 4 °C for up to 1 year, but warm it to ambient temperature before use.

6. A white “string-like” material observed at the bottom of the container indicates significant microbiological growth. If present, discard and prepare again.

C.1.14 Preparing Lithium Borate/Gluconate Eluent1. In a 1-liter volumetric flask, add 20 mL of the 50X lithium borate/gluconate

concentrate and dissolve in 500 mL of DI water. Add 120 mL of HPLC-grade acetonitrile. Mix and fill to the mark with DI water.

2. Vacuum degas through a 0.45-µm aqueous / organic membrane.

The background conductivity of the lithium borate/gluconate eluent is between 220 and 270 µS.


C

C.2 Alkali and Alkaline Earth Cations, Ammonium, and Amines

Figure C-9 1-ppm Standard

Table C-1 Required Instrumentation

Instrument Part Number

Alliance, 2695 Separations Module or Breeze (with column heater, seal wash, and degasser)

N/A

432 Conductivity Detector 043061

busSAT/IN Module 200415

Empower/Breeze data processing Contact Waters


C
C.2.1 Preparing Eluent
1. Add 0.029 g of EDTA as the free acid into a 1-liter plastic volumetric flask.

2. Dissolve in 500 mL of DI water with a stirring bar for 30 min.

3. Add 30 mL of 100 mM HNO3 (or 189 µL of concentrated HNO3).

4. Dilute to volume with DI water.

5. Vacuum degas through a 0.45-µm aqueous-compatible membrane to remove excess EDTA crystals.

6. Store in a plastic container at ambient temperature. Discard after 1 month.

C.2.2 Preparing Standards

It is recommended that you use certified 1000-ppm anion standards with this method. If unavailable, see Section C.2.7, Preparing Stock Reagent, for uncertified standard preparation.

Prepare at least three mixed analyte standards, using plastic volumetric flasks, within the expected range of the sample analyte concentration. This method is linear from 0.05 to 20 ppm for lithium, sodium, and ammonium, and 0.05 to 50 ppm for potassium, magnesium, and calcium. Above these concentrations, the response is off scale. After the multi-point

Table C-2 Analysis Conditions

Condition Value

Column IC-Pak C/MD

Eluent 3 mM HNO3/0.1 mM EDTA

Back conductivity 1250 ±50 µS

Degas Continuous

Flow rate 1 mL/min.

Backpressure 2100 psi

Temperature 30 °C for column heater, 35 °C for detector

Injection 100 µL

Needle wash 12% AcCN in DI water

Detection Indirect conductivity

Base range 2000

Attenuation 100 µS/Volt unattenuated

Polarity Negative


C

calibration curve is validated, a single-point calibration curve within the expected analyte concentration is appropriate for future calibrations.

You can use this method for the analysis of Rb, Cs, Sr, and Ba.

C.2.3 Preparing a Sample1. Determine the expected range of analyte concentration and other anionic

component in the sample matrix. Sodium should be less than 20-ppm for best results.

2. Dilute the sample with DI water, if necessary.

3. If the sample contains high amounts of neutral organics or is highly colored, pass the diluted sample through a C18 Sep-Pak cartridge. Cations pass through unretained. There can be residual Na contamination from the cartridge.

4. Filter samples containing suspended solids through a 0.45-µm aqueous-compatible disk before injection. Failure to filter solids can increase column backpressure.

Note: For best results, ensure sample pH is between 2 and 7 (especially the alkaline earth cations). Samples with pH less than 10 are appropriate for the alkali cations, ammonium, and amines.

5. For samples with pH less than 2, dilute the sample 1:10 with DI water or treat the sample with an Alltech IC-OH cartridge to remove anions and neutralize pH.

C.2.4 Empower Data Processing Method

Table C-3 IC Processing Method Using Peak Apex for Retention Time

Process Values

Integration Peak Width = 30.0

Minimum Area = 3000

Inhibit Intg. = 0 to 2 min.

Threshold = 25 to 40

Minimum Height = 500

Calibration Averaging = None

Update RT = Never

Peak Match = Closest

Quant By = Peak Area

Fit Type = Linear for multi-point calibration, Linear Through Zero for single-point calibration


C

C.2.5 Method Detection Limits

Figure C-10 25-ppb Cation Standard

Based on this representative chromatogram using a 100-µL injection in a 2695 Separations Module, the estimated detection limits, as ppb, at three times signal to noise (S/N) are as follows:

• Lithium = 1

• Potassium = 15

• Sodium = 5

• Magnesium = 10

• Ammonium = 5

Report Analyte Name

Analyte Retention Time

Peak Area

Amounts

Table C-3 IC Processing Method Using Peak Apex for Retention Time (Continued)

Process Values


C

• Calcium = 15

You can achieve lower detection limits by using a 250-µL injection.

C.2.6 Examples of Use

Figure C-11 Typical Drinking Water, No Dilution Required

Figure C-12 Typical Municipal Wastewater, Diluted 1:50, Overlay of Duplicate Injections


C

Note: Alkyl and alkanol amine analysis standards are between 1 and 5 ppm, 3 mM HNO3/0.1 mM EDTA/3% AcCN.

C.2.7 Preparing Stock Reagent

Because it is difficult to prepare a stock eluent for this column, it is recommended to prepare fresh working eluent.

To prepare stock reagent:

1. In a 1-liter plastic volumetric flask, add 0.029 g of EDTA (as the free acid, not its salts) in 800 mL of DI water. Place on a magnetic stir plate and stir for 10 minutes.

2. While stirring, add 189 µL of concentrated nitric acid and mix for 5 minutes.

3. Remove the stirring bar and fill to the mark with DI water.

4. Filter through a 0.45-µm aqueous-compatible membrane filter before use. There can be some remaining white crystals on the filter (EDTA). This does not affect the performance of the eluent. Discard the filter.


D

Appendix DValidation Support

This appendix provides information about:

• Validation regulation overview

• Waters®

regulatory compliance support

Validation Regulation Overview

Federal regulatory codes require that instrumentation and automated systems used for generation, measurement, and assessment of data undergo:

• Operational qualification (performance verification) following repairs, maintenance, and substantial periods of operation

• Routine maintenance

Federal regulatory codes also require that laboratories maintain:

• Written Standard Operating Procedures (SOPs) that indicate dates of operational qualification and maintenance

• Logs of results

Note: Designate a person to be responsible for maintaining federally required records.

Waters Regulatory Compliance Support

Waters provides a wide range of documentation and services to assist customers in complying with the following areas of Standard Operating Procedure regulatory requirements:

• Basic operation

• Instrument maintenance

• Error messages, diagnostics, and tests

• Instrument performance qualification (calibration)

Basic Operation

Regulatory requirements regarding proper instruction for preparing, programming, and operating the 432 Detector are satisfied by the Waters 432 Conductivity Detector Operator’s Guide.

Validation Support 109

D

Instrument Maintenance

Chapter 5, Maintenance, in the Waters 432 Conductivity Detector Operator’s Guide satisfies regulatory requirements for routine instrument maintenance. Chapter 5 includes:

• Maintenance considerations

• Calibration adjustment

• Replacing the flow cell

• Replacing fuses

• Summary of 432 Detector error messages

• Troubleshooting tables

Additional Waters Support

For more information about compliance support products and services, contact Waters Technical Service Department.

Validation Support 110

I NDEX

Index

AAuto Base 59Auto Zero 36, 39, 46, 59

BBalance 39Balance key 58Base Range 62Base Range key 58Baseline

drift 85noise 85

Beep-on-error 60Beep-on-keystroke 60Bubbles, removing 84Bus LAC/E connections 41Bus SAT/IN connections 40

CCarbonate absorption, minimizing 66Chart Mark key 59Chart recorder connections 45Chart recorder offset 58Clear key 59Compression screw 50Configuration, system 68Connections

auto zero input 46Bus SAT/IN to Bus LAC/E 41chart recorder 45marker input 45Millennium32 39PowerLine controller 37

Containers, selecting and preparing 65Contamination, removal. See passivationConventions, documentation 24

DDisplay 57Documentation

conventions 24related 23

EEluent

anion, preparing 70cation, preparing 70general guidelines 69high-pH 65nitric acid, preparing 70

Eluent handling 63Error messages 57, 83

FFlow cell

removing bubbles 84theory 27

Fluid connectionsassembling fittings 50making connections 51

IIEEE-488

address 38connector 37

Initialization self-test 57Integrator

offset 58output 36, 62sensitivity 39sensitivity range multiplier 58

Ion chromotography methods 91

Index 111

INDEX

KKey descriptions 58–60

LLAC/E connections. See Bus LAC/E

connectionsLeak Alert output 36

MMarker input 36, 45Marker output 36, 44, 59Millennium32 connections 39

NNitric acid eluent, preparing 70Noisy baseline, troubleshooting 85

OOffset

chart recorder 58integrator 58polarity 58

PPassivation 53Polarity key 58, 63Power requirements 31Power switch 57PowerLine operation 39Pulse dampener 52, 69

I

RRecorder

output 36, 45, 62sensitivity 39

Related documentation 23Remote key 58Response key 59

SSample preparation 67Sensitivity Range key 58Shift key 59Soda lime tube, using 66Spare parts 90Specifications 87Standards

anion, injecting 72anion, preparing 71cation, injecting 76cation, preparing 74concentration 70shelf-life 70

Standby setup 61Storage, long-term 62System configuration 68

TTemperature equilibration 62Temperature key 58Time constant, detector 59Troubleshooting 82Tubing

cutting polymeric 50cutting steel 49

Index 112

INDEX

UUnpacking the 432 Detector 31

VValidation support 109Voltage, operating 34

ranges 34

WWater purity 64

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Index 113

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Waters 432 Conductivity Detector · Waters 432 Conductivity Detector Operator’s Guide 34 Maple...

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