iso TOC cube: new innovations from a familiar company
Advances in Stable Isotope Techniques & Applications, University of CalgaryTuesday June 4th, 2013
Arthur Kasson, IRMS Product Managerelementar Americas Inc.
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•Compact, bench-top IRMS
•100% high purity stainless steel horizontal vacuum housing
•Extremely high vacuum conductance means only a single
turbomolecular pump is required
•100V dynamic range linear analyzer
•Robust thorium coated ionization filament
•10 year warranty of Faraday Collectors
•Modular electronics for simple maintenance
•High stability electromagnet with no need for water cooling
•Fully automated analysis and diagnostics through IonVantage software
•Market leading performance specifications
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Sensitivity Absolute sensitivity of CO 2 (molecules/ion)
850 DI mode1200 CF mode
H3+ correction factor < 8.0 ppm/nA
H3+ factor stability < 0.03 ppm/nA/hr
Mass Resolution (10% valley definition) 100
Gas IsotopeInternal Precision
1σ ‰Linearity ‰ / nA
CO2 δ13Cδ18O
≤ 0.06≤ 0.06
≤ 0.02≤ 0.04
N2 δ15N ≤ 0.06 ≤ 0.02
H2 δD ≤ 0.20 -
IRMS
Reference Gas
IsoPrime100 Specifications
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The main applications for TOC are environmental forensics and ecology
1. River nutrient and food webs
2. Agricultural run off into water systems
3. Soil dynamics
4. Water quality analysis and pollution
5. Marine & estuarine dynamics
Total Organic carbon (TOC) IRMSKey Applications
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1. Variable sample feeding
2. High temperature digestion with matrix separation (up to 1200C)
3. Highly stable operation and results
4. NDIR detection of TOC in the ppb to percentage range (can also measure TNb)
5. Ability to remove excess salt via ash crucible
Total Organic carbon (TOC) IRMSUnique Capabilities
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Preparation off-line
Large sample sizes, complicated methodology, specialised equipment, analysis by dual inlet, slow
Iso TOC cubeCurrent Techniques
Wet oxidation TOC-IRMS
Using UV or persulfate for oxidation of the sample. Few samples can be analysed before halide gasses corrode reaction vessel, salt deposition in flow lines, consumption of halogen trap
EA-IRMS
Concentration by evaporation or lyophilisation, analysis by EA-IRMSDoes not work well when high concentrations of inorganic salt are present
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Elementar have over 30 years of experience in manufacturing TOC analysers
The vario TOC cube is the latest version in the cube format
Iso TOC Cube
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Integrated 50 position liquid sampler with integrated automated sample feeder
Iso TOC CubeFeatures
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Screwless casing with easy access to 5 sides of the instrument
Simple maintenance with immediate access to all parts
Features
Iso TOC Cube
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Furnace
Syringe pump
Acid reservoirDrying tube
Halogen trap
Multiport valve
Features
Iso TOC Cube
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Use of ball & clamp fittings throughout the instrument for simple maintenance with no need for tools
Ball & Clamp Fittings
Iso TOC Cube
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•Requires interface for IRMS for coupling to IsoPrime100
Benefits during IRMS
Iso TOC Cube
•Iso TOC cube uses direct analysis of TIC & TOC
•Does not use subtraction method (TC - TIC = TOC)
•High temperature oxidation furnace for combustion of C to CO2
•Does not use wet oxidation (persulfate/UV oxidation)
•O2 carrier gas used
•Does not use synthetic air
•Combustion tube containing CuO @ approx 950°C•Does not use expensive platinum
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IRMS Interface – Trap TIC/TOC CO2
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IRMS Interface Introduction
Iso TOC Cube
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CO2 Column Trapping
Iso TOC Cube
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IRMS Interface – Release Trapped CO2
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CO2 Column Release to the IRMS
Iso TOC Cube
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System configuration
• Exchange from O2 to He carrier gas
• Purge and trap adsorption column for peak focusing (no liquid nitrogen needed)
• reduction furnace to remove interference species and residual oxygen
13/05/2011 (7.33 to 10.24)
TOC-IRMS Settings
C-concentration ~ 1ppm
Sample volume ~ 3.5ml
CO2 Adsorption by Silica gel
Trap 550 uA
IR bridged (1/16th" Haler)
Peak Ave time N = 285
He Purge = 30s
Sample nA δ13C
CitricAcid1 5.30 -18.04CitricAcid2 4.65 -17.27CitricAcid3 4.60 -17.23CitricAcid4 4.37 -17.28CitricAcid5 4.25 -17.48CitricAcid6 4.48 -17.15CitricAcid7 4.53 -17.24CitricAcid8 4.43 -17.24CitricAcid9 4.38 -17.24
CitricAcid10 4.46 -17.23
Ave -17.26SD 0.089
~1ppm C Precision
Iso TOC Cube
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13/05/2011 (10.41 to 13.15)
TOC-IRMS Settings
C-concentration ~ 0.15ppm
Sample volume ~ 3.5ml
CO2 Adsorption by Silica gel
Trap 550 uA
IR bridged (1/16th" Haler)
Peak Ave time N = 285
He Purge = 30s
Sample nA δ13C
DI water 5 0.35 -33.70DI water 6 0.36 -34.19DI water 7 0.32 -34.06DI water 8 0.37 -34.64DI water 9 0.33 -34.54DI water 10 0.32 -34.74
Ave -34.31SD 0.40
~0.15ppm Water
Iso TOC Cube
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10/05/2011 (7.38 to 16.12)
TOC-IRMS Settings
C-concentration ~ 10ppm
sample vol ~ 1.5ml
CO2 Adsorption by Silica gel
Trap 200 uA
IR bridged (1/16th" Haler)
Peak Ave time N = 285
He Purge = 30s
Sample nA δ13c Ave std dev ActualANU Sucrose 1 6.33 -11.65ANU Sucrose 2 6.29 -10.72ANU Sucrose 3 6.35 -10.57ANU Sucrose 4 6.44 -10.52 -10.55 0.04 -10.50Citric Acid 1 6.48 -16.18Citric Acid 2 6.47 -16.24Citric Acid 3 6.4 -16.17Citric Acid 4 6.35 -16.10 -16.17 0.06 -16.00RossmSugarA1 6.35 -15.92RossmSugarA2 6.18 -15.90RossmSugarA3 6.26 -15.94RossmSugarA4 6.13 -15.90 -15.92 0.02 -16.30Glutamic AcidA1 6.28 -26.19Glutamic AcidA2 6.16 -26.21Glutamic AcidA3 6.13 -26.11Glutamic AcidA4 6.04 -26.21 -26.18 0.05 -26.10Glutamic AcidB1 5.95 -27.89Glutamic AcidB2 5.98 -27.92Glutamic AcidB3 5.91 -27.95Glutamic AcidB4 6.29 -27.98 -27.94 0.04 -28.40Testsugar1 6.02 -25.57Testsugar2 6.11 -25.55Testsugar3 6.01 -25.56Testsugar4 6.13 -25.56 -25.56 0.01 -26.00RossmSugarB1 5.98 -25.16RossmSugarB2 5.98 -25.18RossmSugarB3 5.99 -25.13RossmSugarB4 5.96 -25.13 -25.15 0.02 -25.70ANU Sucrose 5 5.96 -10.80ANU Sucrose 6 5.93 -10.57ANU Sucrose 7 5.89 -10.53ANU Sucrose 8 5.88 -10.54 -10.5467 0.02 -10.50
TOC-IRMS Accuracy
Iso TOC Cube
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-30 -25 -20 -15 -10 -5
-30
-25
-20
-15
-10
-5
0
f(x) = 1.02390477798457 x + 0.285152648933835R² = 0.998936855474399
Experimental δ13C
Th
eo
reti
ca
l δ1
3C
TOC-IRMS Accuracy
Iso TOC Cube
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Stability (precision) and memory effect
Absolute shifts between 11-39‰Low C (5-12nA signal)
Absolute shifts between 6-73‰High C (16-55nA signal)
Very good precision: ≤ 0.20‰ and ≤ 0.1‰ for shift below 30‰
Still very good precision: ≤ 0.20‰(shift larger than 60‰ ≤ 0.30‰)
SignalAbsolute
shiftInjection 2,3,4
d13C stdev
Injection 3,4,5
d13C stdev
[nA] [‰] [‰] [‰]
5 11.14 0.05 0.045 30.10 0.03 0.045 38.62 0.19 0.105 37.70 0.15 0.07
12 23.08 0.02 0.0212 37.56 0.06 0.0412 18.43 0.10 0.0412 10.92 0.05 0.0312 30.34 0.09 0.0412 37.79 0.07 0.0512 14.55 0.09 0.0212 23.00 0.10 0.0516 38.87 0.13 0.0816 17.51 0.09 0.1016 15.65 0.18 0.0255 73.07 0.27 0.1455 62.30 0.23 0.1355 15.41 0.05 0.0555 16.10 0.13 0.0255 11.16 0.04 0.0655 5.61 0.04 0.02
With 5 injections
all data ≤ 0.10‰ (shift larger than 60‰ ≤ 0.20‰)
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Accuracy
All data corrected with 2 points calibration
curve Caffeine (IAEA-600)
d13C
Glucose (IAEA-CH6)
d13C
-
27.77‰
-
10.45‰
Average difference between
measured and target value
TOC measured 13C [‰]
-60 -50 -40 -30 -20 -10 0
targ
et
13C
[‰]
-60
-50
-40
-30
-20
-10
0
Only in 3 over 13
measurements differences ≥
0.15‰
y = 1.00031x + 0.04485r2 = 0.9999
0.09‰
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Linearity of the system and concentration range(data courtesy of Dr. Chiara Cerli – U. Amsterdam)
DOC [mgC L-1]
0 20 40 60 80 100 120 140 160
13 C
[‰
]
-51
-48
-30
-27
-24
-21
-18
-15
-12
-9
IRMS signal [nA]
0 9 18 27 36 45 55 64 73
citric acid
benzoic acid
L-tryptophane
acetovanillone
urea caffeine
mixture
humic acid
melamine glucose
except for
L-trypthophane (0.07
‰/nA)
humic acid (0.06 ‰/nA)
glucose (0.04 ‰/nA)
Between 5-150ppm (5-70nA)
Very good linearity:
≤ 0.03 ‰/nA
Between 1-150ppm (1-70nA)
Very good linearity:
≤ 0.03 ‰/nA
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Real samples
Rice(std dev 0.05‰)
Moss(std dev 0.17‰)
Forest floor(std dev 0.15‰)
Peat(std dev 0.03‰)
H horizon from Podzol(std dev 0.02‰)
DOC [mgC L-1]
0 20 40 60 80 100 120 140
13 C
[‰
]
-33.2
-32.8
-32.4
-28.0
-27.6
-27.2
-26.8
-26.4
-26.0
-25.6
peat
forest floor
H podzolmoss
rice
DOM extracted from:
0.5 ml injection, different
concentrations
Measured very well
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d13C d13C
10-150 mgC L-1 stdev10-100 mgC L-
1 stdev
[‰] [‰] [‰] [‰]
Citric acid -25.35 0.18 -25.44 0.11
Benzoic acid -28.92 0.34 -28.91 0.40
L-Trypthophane -11.35 0.31 -11.47 0.09
Acetovanillone -30.53 0.15 -30.61 0.07Acetovanillone (fix C)
-30.58 0.03 -30.57 0.03
Urea -50.05 0.17 -50.13 0.12
Caffeine -49.06 0.23 -49.16 0.18
Mixture -28.93 0.62 -29.08 0.68
Humic acid -26.18 0.30 -26.21 0.35
Humic acid (fix C) -26.34 0.03 -26.35 0.03
Melamine -19.77 0.23 -19.89 0.15
Glucose -11.16 0.21 -11.24 0.19
DOM_Moss nd nd -32.70 0.17
DOM_Moss (fix C) -32.81 0.09 -32.80 0.09
Constant C injection
(25mgC, ~22nA)
Inj vol 0.08-2.5ml
Very good std dev:
≤ 0.09 ‰
Constant inj vol (0.5ml)
Various C
concentrations
(10-150 mg L-1)Good std dev:
≤ 0.30 ‰
Real samples: concentration vs volume(data courtesy of Dr. Chiara Cerli – U. Amsterdam)
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Conclusions
stable system (large ‰ shift)
accurate
Wide range of system linearity (2-80nA <0.03‰/nA) flexibility for handling real samples
Injection volumes (0.05-4ml)
1 nA/µg C
Performances very satisfying
`high throughput, easy to use and maintain
Very interesting tool that widen opportunities for studies in environmental research
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Special thanks go out to Dr. Chiara Cerli at the University of Amsterdam (Institute for Biodiversity and Ecosystem Dynamics) for providing us with additional data.
Acknowledgements
Paul Wheeler, Mike Seed, Will Price, Rob Berstan
Federherr E., H.P. Sieper, Lutz Lange, H.J. Kupka, R. Dunsbach, F. Volders
Schematic Outline of the Iso TOC CubeINTRODUCTION
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Sample vial
SpargerFurnace
Condenser
Sample Syringe
Halogen trap
Nafion Membrane
Drying tube
IR detector
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Acidify Sparge Vessel to remove TICSTEP ONE
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Flush sample lines to waste and fill syringe
STEP TWO
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Dose sample for TIC removal
STEP THREE
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Measure TIC
STEP FOUR
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Measure TOC
STEP FIVE
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