How%20Does%20the%20Sample%20Affect%20the%20Measurement%20of%20Different%20Carbon%20Fractions?

1
How Does the Sample Affect the Measurement of
Different Carbon Fractions?

• Judith C. Chow Desert Research InstituteReno,
  NVpresented at the
• International Workshop for the Development of
  Research Strategies for the Sampling and Analysis
  of Organic and Elemental Carbon Fractions in
  Atmospheric Aerosols
• Durango, Colorado
• March 4, 2003

2
Types of Sample Effects

• Filter samples
• Carbon particle composition
• Chemical and physical interactions between carbon
  and other constituents

3
Filter Sample Biases

• Non-uniform filter deposit biases scaling from
  punch to whole filter
• Non-uniform filter punch deposit biases optical
  monitoring and charring
• Too light or too dark particle deposits make
  pyrolysis correction uncertain
• More heavily loaded samples require longer
  combustion time at each temperature step
• Organic vapor adsorption and volatilization in
  filter biases OC and pyrolysis correction

4
Non-Uniform Sample Deposits(Chow, 1995)
5
Carbon Particle Composition

• Ambient mixtures, source mixtures, and pure
  carbon substances do not respond to heating in
  the same way
• Thermal evolution protocols are poorly documented
  and characterized
• Thermal evolution temperatures are not optimized
  to bracket compositions
• Carbonates are not present in most ambient PM2.5
  samples, and CaCO3 evolves at gt800 C if they are
  present
• Samples do not respond the same as calibration
  standards

6
At Least 15 International Thermal Combustion
Carbon Methods

• Oregon Graduate Institute thermal optical
  reflectance (TOR) (Huntzicker et al., 1982)
• IMPROVE TOR and thermal optical transmittance
  (TOT) (Chow et al., 1993, 2001)
• NIOSH TOT (NIOSH, 1999)
• ACE-Asia TOT (Mader et al., 2001)
• Hong Kong University of Science and Technology
  UST-3 TOT (Yang and Yu, 2002)

7
At Least 15 International Thermal Combustion
Carbon Methods (continued)

• Meteorological Service of Canada MSC1 TOT (Sharma
  et al., 2002)
• U.S. Speciation Trends Network (STN) TOT
• General Motors Research Laboratory two
  temperature (Cadle et al., 1980)
• Brookhaven National Laboratory two temperature
  (Tanner et al., 1982)
• Japanese two temperature (Mizohata and Ito,
  1985)

8
At Least 15 International Thermal Combustion
Carbon Methods (continued)

• Two-temperature thermal manganese
  oxidation (Fung, 1990)
• RP two temperature (Rupprecht et al., 1995)
• French two-temperature pure oxygen
  combustion (Cachier, 1989a, 1989b)
• Lawrence Berkeley Laboratory continuous
  temperature ramp (Novakov, 1982)
• German VDI extraction/combustion (Verein
  Deutcher Ingenieure, 1999)

9
Differences among Operating Parameters

• Combustion atmospheres
• Temperature ramping rates
• Temperature plateaus
• Residence time at each plateau
• Optical monitoring configuration and wavelength
• Standardization

• Sample aliquot and size
• Oxidation (C to CO2) catalyst
• Evolved carbon detection method
• Carrier gas flow through or across the sample
• Location of the temperature monitor relative to
  the sample

10
Laboratory intercomparisons are not consistent
(Schmid et al., 2001)
11
Same method intercomparisons show differences
(Schauer et al., 2003)
12
Comparison of EC Concentrations between TMO and
TOR Methods(Fung et al., 2002)
13
IMPROVEcarbon thermogram
Sample from Hong Kong urban site on 04/17/01 with
9.9 0.8 ug/m3 OCand 7.8 0.8 ug/m3 EC
STNcarbon thermogram
14
Carbon Source Profiles(Watson et al., 1994)
Diesel-fueled vehicles
Gasoline-fueled vehicles
15
Hong Kong Vehicle Exhaust Profiles (Cao et al.,
2003)
Source Differences in Carbon Fractions
16
BRAVO Source Profiles (Chow et al., 2003)
Source Differences in Carbon Fractions
17
No relationship between EC and carbonate by
acidification(Chow and Watson, 2002)
IMPROVE samples and IMPROVE protocol
18
Carbon Standards Should be Similar to Samples

• Water-soluble organics (e.g., sucrose, KHP,
  organic acids)
• Carbon dioxide and methane
• Nebulized charcoal resuspension
• Carbon blacks
• Graphite powders
• Organic dyes (e.g., nigrosin, C48N9H51)
• Carbon arc emissions
• Simulated source emissions
• Neutral density filters

19
Some Organic Compounds Absorb Light(Justus et
al., 1993)
Transmission through nigrosin (C48N9H51) dye
20
Chemical Composition of Carbon Black and Fresh
Soot(Watson and Valberg, 2001)

21
Chemical and Physical Interactions of Carbon with
Other Constituents

• Oxidation interactions
• Catalytic reactions
• Optical interactions

22
Increasing rate of graphite oxidation by MnO2
(Fung, 1990)
1000K
900K
833K
800K
23
Catalytic reactions with glass-fiber filter (525
C)(Lin and Friedlander, 1988a, 1988b, 1988c)
Na, K, Pb, Mn, Fe, Ca, V, Cu, Ni, Co, and Cr
compounds are known catalysts
24
Carbon Fractions are Probably Different for
Different Applications

• Visibility and radiation balance
• Visible light absorption and scattering by
  particles in the atmosphere
• Source attribution
• Consistently define fractions in source and
  receptor samples
• Health effects
• Absorption of toxic substances on EC
• Chemical and physical models
• Reaction surfaces, catalytic properties

25
Research Needs

• Critically summarize and review non-atmospheric
  carbon literature
• Document methods (combustion temperatures,
  ramping rates, residence times, optical pyrolysis
  corrections)
• Prepare different standards representing
  different black carbon sources
• Perform optical modeling to verify changes in
  absorption and scattering properties

26
Research Needs (continued)

• Optimize carbon fractions for source
  identification
• Quantify effects of pyrolysis on and within a
  filter to resolve reflectance/transmittance
  differences
• Quantify effects of non-absorbing particles,
  optical monitoring wavelengths, initial darkness,
  carbonate deposits, and oxygen-supplying minerals
• Calibrate reflectance and transmittance
  measurements and report with carbon fractions at
  beginning, minimum, oxygen introduction, and end
  of analysis

27
References

• Cachier, H. Bremond, M.P. and Buat-Ménard, P.
  (1989a). Thermal separation of soot carbon.
  Aerosol Sci. Technol., 10(2)358-364.
• Cachier, H. Bremond, M.P. and Buat-Ménard, P.
  (1989b). Determination of atmospheric soot
  carbon with a simple thermal method. Tellus,
  41B(3)379-390.
• Cadle, S.H. Groblicki, P.J. and Stroup, D.P.
  (1980). An automated carbon analyzer for
  particulate samples. Anal. Chem.,
  52(13)2201-2206.
• Cao, J.J. Ho, K.F. Lee, S.C. Fung, K. Zhang,
  X.Y. Chow, J.C. and Watson, J.G. (2003).
  Characterization of roadside fine particulate
  carbon and its 8 fractions in Hong Kong. Sci.
  Total Environ., submitted.
• Chow, J.C. Watson, J.G. Pritchett, L.C.
  Pierson, W.R. Frazier, C.A. and Purcell, R.G.
  (1993). The DRI Thermal/Optical Reflectance
  carbon analysis system Description, evaluation
  and applications in U.S. air quality studies.
  Atmos. Environ., 27A(8)1185-1201.

28
References (continued)

• Chow,J.C. (1995). Summary of the 1995 AWMA
  critical review Measurement methods to
  determine compliance with ambient air quality
  standards for suspended particles. EM 1,
  12-15.
• Chow, J.C. Watson, J.G. Crow, D. Lowenthal,
  D.H. and Merrifield, T. (2001). Comparison of
  IMPROVE and NIOSH carbon measurements. Aerosol
  Sci. Technol., 34(1)23-34.
• Chow, J.C. and Watson, J.G. (2002). PM2.5
  carbonate concentrations at regionally
  representative Interagency Monitoring of
  Protected Visual Environment sites. J. Geophys.
  Res., 107(D21)ICC 6-1-ICC 6-9. doi
  10.1029/2001JD000574.
• Chow, J.C. Watson, J.G. Kuhns, H.D.
  Etyemezian, V. Lowenthal, D.H. Crow, D.J.
  Kohl, S.D. Engelbrecht, J.P. and Green, M.C.
  (2003). Source profiles for industrial, mobile,
  and area sources in the Big Bend Regional Aerosol
  Visibility and Observational (BRAVO) Study.
  Chemosphere, submitted.
• Fung, K.K. (1990). Particulate carbon speciation
  by MnO2 oxidation. Aerosol Sci. Technol.,
  12(1)122-127.
• Fung, K.K. Chow, J.C. and Watson, J.G. (2002).
  Evaluation of OC/EC speciation by thermal
  manganese dioxide oxidation and the IMPROVE
  method. J. Air Waste Manage. Assoc.,
  52(11)1333-1341.

29
References (continued)

• Huntzicker, J.J. Johnson, R.L. Shah, J.J. and
  Cary, R.A. (1982). Analysis of organic and
  elemental carbon in ambient aerosols by a
  thermal-optical method. In Particulate Carbon
  Atmospheric Life Cycle, G.T. Wolff and R.L.
  Klimisch, Eds. Plenum Press, New York, NY, pp.
  79-88.
• Justus, B.L. Huston, A.L. and Campillo, A.J.
  (1993). Broadband thermal optical limiter.
  Appl. Phys. Lett., 63(11)1483-1485.
• Lin, C. and Friedlander, S.K. (1988a). Soot
  oxidation in fibrous filters. 1. Deposit
  structure and reaction mechanisms. Langmuir,
  4(4)891-898.
• Lin, C. and Friedlander, S.K. (1988b). Soot
  oxidation in fibrous filters. 2. Effects of
  temperature, oxygen partial pressure, and sodium
  additives. Langmuir, 4(4)898-903.
• Lin, C.I. and Friedlander, S.K. (1988c). A note
  on the use of glass fiber filters in the thermal
  analysis of carbon containing aerosols. Atmos.
  Environ., 22(3)605-607.

30
References (continued)

• Mader, B.T. Flagan, R.C. and Seinfield, J.H.
  (2001). Sampling atmospheric carbonaceous
  aerosols using a particle trap impactor/denuder
  sampler. Environ. Sci. Technol., 35(24),
  4857-4867.
• Mizohata, A. and Ito, N. (1985). Analysis of
  organic and elemental carbon in atmospheric
  aerosols by thermal method. Annual Report of the
  Radiation Center of Osaka Prefecture,
  26(0)51-55.
• NIOSH (1999). Method 5040 Issue 3 (Interim)
  Elemental carbon (diesel exhaust). In NIOSH
  Manual of Analytical Methods, 4th ed. National
  Institute of Occupational Safety and Health,
  Cincinnati, OH.
• Novakov, T. (1982). Soot in the atmosphere. In
  Particulate Carbon Atmospheric Life Cycle, G.T.
  Wolff and R.L. Klimisch, Eds. Plenum Press, New
  York, NY, pp. 19-41.

31
References (continued)

• Rupprecht, E.G. Patashnick, H. Beeson, D.E.
  Green, R.E. and Meyer, M.B. (1995). A new
  automated monitor for the measurement of
  particulate carbon in the atmosphere. In
  Proceedings, Particulate Matter Health and
  Regulatory Issues, J.A. Cooper and L.D. Grant,
  Eds. Air and Waste Management Association,
  Pittsburgh, PA, pp. 262-267.
• Schmid, H.P. Laskus, L. Abraham, H.J.
  Baltensperger, U. Lavanchy, V.M.H. Bizjak, M.
  Burba, P. Cachier, H. Crow, D.J. Chow, J.C.
  Gnauk, T. Even, A. ten Brink, H.M. Giesen,
  K.P. Hitzenberger, R. Hueglin, C. Maenhaut,
  W. Pio, C.A. Puttock, J. Putaud, J.P.
  Toom-Sauntry, D. and Puxbaum, H. (2001).
  Results of the "Carbon Conference" international
  aerosol carbon round robin test Stage 1.
  Atmos. Environ., 35(12)2111-2121.
• Sharma, S. Brook, J. Cachier, H. Chow, J.C.
  Gaudenzi, A. and Lu, G. (2002). Light
  absorption and thermal measurements of black
  carbon in different regions of Canada. J.
  Geophys. Res., 107(D24)AAC 11-1-AAC 11-11.
  doi10.1029/2002JD002496.

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References (continued)

• Tanner, R.L. Gaffney, J.S. and Phillips, M.F.
  (1982). Determination of organic and elemental
  carbon in atmospheric aerosol samples by thermal
  evolution. Anal. Chem., 54(9)1627-1630.
• Verein Deutcher Ingenieure (1999). Method 2465
  Part 2 Measurement of soot (ambient
  air)-Thermographic determination of elemental
  carbon after thermal desorption of organic
  carbon. Prepared by Verein Deutcher Ingenieure,
  Beuth, Berlin, FRG.
• Watson, A.Y. and Valberg, P.A. (2001). Carbon
  black and soot Two different substances. Am.
  Industrial Hygiene Assoc. J., 62(Mar/Apr)218-228.
  
• Watson, J.G. Chow, J.C. Lowenthal, D.H.
  Pritchett, L.C. Frazier, C.A. Neuroth, G.R.
  and Robbins, R. (1994). Differences in the
  carbon composition of source profiles for diesel-
  and gasoline-powered vehicles. Atmos. Environ.,
  28(15)2493-2505.
• Yang, H. and Yu, J.Z. (2002). Uncertainties in
  charring correction in the analysis of elemental
  and organic carbon in atmospheric particles by
  thermal/optical methods. Environ. Sci. Technol.,
  36(23)5199-5204.