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Ion Analysis 2011 IMPROVE Steering Committee Meeting

Frostburg, Maryland

Eva Hardison, David Hardison, Buddy Goodnight, Dorie Pickett, Melville Richards, Christine Van Hise,

Steven Walters, Michelle Conner

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NPS Ions Contract Awarded to RTI March 2011

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Ion Analysis for IMPROVE

• Analysis and reporting of ion masses on nylon filters from the IMPROVE network.

• Preparation of impregnated filters for SO2 sampling and analysis and reporting of sulfate ion mass on the exposed filters.

• Preparation of phosphorous acid-impregnated filters for inorganic reduced nitrogen (NHx) and methylamine sampling and analysis, and reporting of NH4

+ and methylamine mass on the exposed filters.

• Occasional studies related to ion analysis:

Analysis of Teflon research filters prepared by UC-Davis for calibration of XRF systems.

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Filters Received Since the Last Steering Committee Meeting

Filter Type/ Analytes

10/15/10 - 3/31/11

4/1/11- 10/15/11

Total

Nylon/Anions 8798 10920 19718

Phosphorous Acid-Coated Cellulose/NH4

+ and MeA

-- 861 861

Nylon/NH4+ -- 380 380

Teflon/Na+, Cl-, NH4

+, SO4= -- 56 56

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Filters Received Since the Last Steering Committee Meeting

0

50

100

150

200

250

300

350

400

450

No. of Filters IMPROVE

NHx

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NHx Study Update

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2010 NHX Study Review

• Ion analyses performed in 2010 revealed an unknown peak in some samples that precluded the quantitation of ammonium ion. The peak was identified as methylamine.

• Subsequent experiments performed at CSU determined that the observed methylamine was an artifact of the sampling, most likely through reaction of NH4

++ formaldehyde.

• UCD prepared sample cartridges from a plastic that is non-reactive with phosphorus acid.

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Analysis of NH4+ in Filter Extracts:

Comparison of Methods

Gradient Dionex ICS-3000 IC (dedicated for NHx)

CS18 Cation Separator, 2 mm

CSRS-300 Auto Regen Mode

Eluent: 100 mM methanesulfonic acid

(MSA); programmed with gradient from 0.5 to 8 mM

Flow rate: 0.3 mL/min

Baseline separation of NH4+ and MeA

Analysis time = 40 min

Isocratic

Dionex Ion Chromatograph (multiple)

CS12A Cation Separator, 4 mm

CSRS-300 Auto Regen Mode

Eluent: 22mN sulfuric acid

Flow rate: 1.0 mL/min NH4

+ and MeA are not separated

Analysis time = 12 - 14 min

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Comparison of Isocratic vs. Gradient IC Methods for NH4+

(15 nylon filters)

y = 1.0019x + 0.0026 R² = 1

0.000

0.500

1.000

1.500

2.000

2.500

3.000

3.500

0.000 1.000 2.000 3.000 4.000

µg NH4+/mL

Isocratic

µg NH4+/mL

Gradient

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NHx Sampling Start Dates (H3PO3-impregnated cellulose filters)

Site Sampling Start Date

BANDS 4/27/11

BONDS* 4/21/11

CEBLS 4/27/11

CHIRS 4/27/11

GLACS 4/21/11

MEVES 4/27/11

ROMOS* 4/21/11

WICAS 4/21/11

YELLS 6/8/11

* Collocated samplers at these sites

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2011 NHx Data Observations

• In the beginning, the collocated (“X”) samplers at BOND and ROMO sometimes sampled improperly (or not at all).

• Field blanks generally are below 2 µg/filter, but show some increase over time.

• No methylamine has been detected in samples analyzed to date.

• The corresponding nylon filter samples that are analyzed for NH4

+ are received later than the cellulose filters. How will this affect the data?

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BONDS Collocated Samplers NH4+

0

20

40

60

80

100

120

140

160

180

0 50 100 150 200

"X" Sampler NH4

+, µg

"S" Sampler NH4+, µg

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ROMO2S Collocated Samplers NH4+

0.0

10.0

20.0

30.0

40.0

50.0

60.0

0.0 20.0 40.0 60.0

"X" Sampler

NH4+, µg

"S" Sampler NH4+, µg

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Nylon/Cellulose Filters: Elapsed Time from Sampling to NH4

+ Analysis

Sampling to Receipt by RTI, days

Receipt by RTI to Analysis, days

Nylon Cellulose Nylon Cellulose

Average 41 12.5 21 5

Minimum 18 2 7 1

Maximum 68 30 35 12

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NHx Cellulose Filter Field Blanks

0.000

0.500

1.000

1.500

2.000

2.500

3/18/11 4/17/11 5/17/11 6/16/11 7/16/11 8/15/11 9/14/11 10/14/11

NH4+, µg

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NHx Sample Storage and Extraction

Older, collapsible glove box New glove box

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Special Studies: UCD Research Filters for

Calibration of XRF Systems

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XRF Reference Filters: Sodium Ion Loadings

y = 0.9701x + 1E-04 R² = 0.9997

0.000

0.020

0.040

0.060

0.080

0.100

0.120

0.140

0.000 0.020 0.040 0.060 0.080 0.100 0.120 0.140

Na+, mg (analyzed)

Na+, mg (grav)

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XRF Reference Filters: Chloride Ion Loadings

y = 0.9912x - 2E-05 R² = 0.9997

0.000

0.020

0.040

0.060

0.080

0.100

0.120

0.140

0.160

0.180

0.200

0.000 0.020 0.040 0.060 0.080 0.100 0.120 0.140 0.160 0.180 0.200

Cl-, mg (analyzed)

Cl-, mg (grav)

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XRF Reference Filters: Ammonium Ion Loadings

y = 1.0015x + 8E-05 R² = 0.9995

0.000

0.020

0.040

0.060

0.080

0.100

0.120

0.140

0.000 0.020 0.040 0.060 0.080 0.100 0.120 0.140

NH4+, mg

(analyzed)

NH4+, mg (grav)

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XRF Reference Filters: Sulfate Ion Loadings

y = 0.9791x + 0.0002 R² = 0.9998

0.000

0.050

0.100

0.150

0.200

0.250

0.300

0.350

0.000 0.050 0.100 0.150 0.200 0.250 0.300 0.350

SO4=, mg

(analyzed)

SO4=, mg (grav)

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XRF Reference Filters Also Contain NO2

- and NO3-

0

5

10

15

20

25

0 5 10 15 20 25

NO

3 u

g

NO2 ug

NO2 and NO3 correlation

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XRF Reference Filters

0

5

10

15

20

25

0 0.1 0.2 0.3 0.4 0.5

Ion Loading, µg

Filter Loading, mg

Nitrite

Nitrate

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Teflon Filter Blanks NO2

- and NO3- Correlation

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

16.0

18.0

20.0

0.0 10.0 20.0 30.0

NO3-,

µg/filter

NO2-, µg/filter

UCD Lab Blanks

NaCl Chamber Blks

AS Chamber Blks

RTI IC System Blks

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Teflon Filter Blanks NH4+ Detected, µg

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

4.50

5.00

0 2 4 6 8 10

NH4+, ug

Blank Filter #

UCD Lab Blanks

NaCl Chamber Blks

AS Chamber Blks

RTI IC System Blanks

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More News from the RTI Ions Lab

• A Dionex (Thermo Fisher Scientific) Model 3000 Ion Chromatograph has been set up and dedicated for levoglucosan analyses.

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Fire at Chiricahua June 8, 2011

Filter ID Levo-

glucosan, µg

K+, µg

CHIR1 6/8/11

0.3 6.2

CHIR1 6/11/11

76.2 18.0

CHIR1 6/14/11

2.1 8.2

CHIR1 6/17/11

4.7 24.9

Extracts analyzed 9/13/11

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Announcements

• Dr. Prakash Doraiswamy, Research Scientist at the University at Albany, will join the Environmental Chemistry Department at RTI on October 31, 2011.

• If you are attending the AWMA Symposium on Air Quality Measurement Methods and Technology in Durham, NC, April 23-26, 2012, you are welcome to visit/tour RTI’s laboratories.

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Thank you, and…