Standard Test Method for Total and Organic Carbon in Water by High Temperature Oxidation and by Coulometric Detection

SCOPE
1.1 This test method covers the determination of total and organic carbon in water and waste water, including brackish waters and brines in the range from 2 to 20 000 mg/L. This test method has the advantages of a wide range of concentration which may be determined without sample dilution and the provision for boat or capillary introduction of samples containing sediments and particulate matter where syringe injection is inappropriate.  
1.2 This procedure is applicable only to that carbonaceous matter in the sample that can be introduced into the reaction zone. When syringe injection is used to introduce samples into the combustion zone, the syringe needle opening size limits the maximum size of particles that can be present in samples. Sludge and sediment samples must be homogenized prior to sampling with a micropipetor or other appropriate sampler and ladle introduction into the combustion zone is required.  
1.3 The precision and bias information reported in this test method was obtained in collaborative testing that included waters of the following types: distilled, deionized, potable, natural, brine, municipal and industrial waste, and water derived from oil shale retorting. Since the precision and bias information reported may not apply to waters of all matrices, it is the user's responsibility to ensure the validity of this test method on samples of other matrices.
1.4 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific precautionary statements, see 9.1 and 10.2.1.

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ASTM D4129-98 - Standard Test Method for Total and Organic Carbon in Water by High Temperature Oxidation and by Coulometric Detection
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NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: D 4129 – 98
Standard Test Method for
Total and Organic Carbon in Water by High Temperature
Oxidation and by Coulometric Detection
This standard is issued under the fixed designation D 4129; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope D 513 Test Methods for Total and Dissolved Carbon Diox-
ide in Water
1.1 This test method covers the determination of total and
D 1129 Terminology Relating to Water
organic carbon in water and waste water, including brackish
D 1193 Specification for Reagent Water
waters and brines in the range from 2 to 20 000 mg/L. This test
D 3370 Practices for Sampling Water from Closed Con-
method has the advantages of a wide range of concentration
duits
which may be determined without sample dilution and the
D 3856 Guide for Good Laboratory Practices in Laborato-
provision for boat or capillary introduction of samples contain-
ries Engaged in the Sampling and Analysis of Water
ing sediments and particulate matter where syringe injection is
D 4210 Practice for Interlaboratory Quality Control Proce-
inappropriate.
dures and a Discussion on Reporting Low-Level Data
1.2 This procedure is applicable only to that carbonaceous
D 5789 Practice for Writing Quality Control Specifications
matter in the sample that can be introduced into the reaction
for Standard Test Methods for Organic Constituents
zone. When syringe injection is used to introduce samples into
the combustion zone, the syringe needle opening size limits the
3. Terminology
maximum size of particles that can be present in samples.
3.1 Definitions—For definitions of terms used in this test
Sludge and sediment samples must be homogenized prior to
method, refer to Terminology D 1129.
sampling with a micropipetor or other appropriate sampler and
ladle introduction into the combustion zone is required.
4. Summary of Test Method
1.3 The precision and bias information reported in this test
4.1 The sample is homogenized or diluted, or both, as
method was obtained in collaborative testing that included
necessary. If the sample does not contain suspended particles
waters of the following types: distilled, deionized, potable,
or high-salt level a 0.200-mL portion is injected into the
natural, brine, municipal and industrial waste, and water
reaction zone. For samples containing solids or high salt levels,
derived from oil shale retorting. Since the precision and bias
portions are placed in combustion boats containing tungsten
information reported may not apply to waters of all matrices, it
trioxide (WO ) or quartz capillaries and introduced into the
is the user’s responsibility to ensure the validity of this test
reaction zone using a ladle. In the reaction zone the heat,
method on samples of other matrices.
oxidation catalyst and oxygen atmosphere convert carbon-
1.4 This standard does not purport to address all of the
aceous matter to carbon dioxide (CO ). The oxygen gas stream
safety concerns, if any, associated with its use. It is the
sweeps the gaseous reaction products through a series of
responsibility of the user of this standard to establish appro-
scrubbers for potentially interfering gases and then to the
priate safety and health practices and determine the applica-
absorption/titration cell. The CO is determined by automatic
bility of regulatory limitations prior to use. For specific
coulometric titration. Calibration by testing known carbon
precautionary statements, see 9.1 and 10.2.1.
content standards is not required, however, standards are
analyzed periodically to confirm proper operation.
2. Referenced Documents
4.2 Carbon dioxide is liberated from carbonates as well as
2.1 ASTM Standards:
from organic matter under the reaction conditions. Organic
carbon is determined by difference between the total carbon
and the inorganic carbon determined separately or by acidify-
This test method is under the jurisdiction of ASTM Committee D-19 on Water
ing a portion of the sample to a pH of 2 or less and sparging
and is the direct responsibility of Subcommittee D19.06 on Methods for Analysis for
Organic Substances in Water.
Current edition approved Dec. 10, 1998. Published March 1999. Originally
published as D 4129 – 82. Last previous edition D 4129 – 88 (1993). Annual Book of ASTM Standards, Vol 11.01.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
D 4129
FIG. 1 Total Carbon and TOC Apparatus
with carbon dioxide-free gas to remove carbonates, bicarbon- organic carbon should be determined by the difference between
ates, and dissolved carbon dioxide prior to total carbon the total carbon and the inorganic carbon concentrations. When
determination. To determine organic carbon by difference the organic carbon determined both by difference and by sparging
inorganic carbon is determined by acid release of carbon agree it is acceptable to determine organic carbon by sparging
dioxide from a portion of the sample or other methods as given for similar samples.
in Test Methods D 513. For discussion of the limitations and 5.5 The relationship of TOC to other water quality param-
guidelines for the use of the sparge technique see 5.4 and the eters such as COD and BOD is described in the literature.
paper by Van Hall.
6. Interferences
4.3 Because of the various properties of carbon-containing
compounds in water, any preliminary treatment of a sample
6.1 Any acidic or basic gas formed in the oxidation of the
prior to injection dictates a definition of the carbon measured.
sample and not removed by the scrubbers will interfere with
Filtration of the sample prior to injection will limit the carbon
the test. Potentially interfering gases that are removed by the
measured to dissolved carbonates and dissolved organic matter.
scrubbers include hydrogen sulfide (H S), hydrogen chloride
Homogenizing permits determination of the carbon in in-
(HCl), hydrogen bromide (HBr), hydrogen iodide (HI), sulfur
soluble carbonates and insoluble organic materials.
dioxide (SO ), sulfur trioxide (SO ) free halogens, halogen
2 3
oxides, and nitrogen oxides. Hydrogen fluoride (HF) may be
5. Significance and Use
removed by bubbling the gas stream through water in the water
5.1 This test method is necessary because of the need for
vapor condenser.
rapid reliable tests for carbonaceous material in waters and
6.2 The capacity of the scrubbers for potentially interfering
sediments.
gases may vary with the type of samples being analyzed. If the
5.2 It is used for determining the concentration of organic
scrubber capacity is exceeded it can be recognized by the
carbon in water that comes from a variety of natural, domestic,
titration continuing beyond the normal analysis time at a higher
and industrial sources. Typically, these measurements are used
rate than the blank and high results for known carbon content
to monitor organic pollutants in domestic and industrial waste
standards as well as by appearance changes in the scrubbers. If
water.
the scrubber capacity is exceeded during an analysis the
5.3 When a sample is homogenized so that particulate,
scrubbers should be replaced and the analysis repeated.
immiscible phases, and dissolved carbon from both organic
Samples containing all concentrations of the potentially inter-
and inorganic sources is determined, the measurement is called
fering species can be analyzed if the analyst uses great care to
total carbon (TC). When inorganic carbon response is elimi-
ensure that the scrubbers are and remain effective for his
nated by removing the dissolved CO prior to the analysis or
samples. The frequency of replacing the scrubbers will depend
the dissolved CO concentration subtracted from the total
on the nature of the samples.
carbon concentration, the measurement is called total organic
carbon (TOC). When particulates and immiscible phases are 7. Apparatus
removed prior to analysis the measurement is called dissolved
7.1 Apparatus for total carbon, organic carbon, and inor-
carbon (DC), or dissolved organic carbon (DOC) if inorganic
ganic carbon determinations—combustion furnace with gas
carbon response has been eliminated.
supply, gas purification train, flow control, acid reaction train,
5.4 Homogenizing or sparging of a sample, or both, may
and carbon dioxide coulometer. Fig. 1 and Fig. 2 show block
cause loss of volatile organics, thus yielding a negative error.
diagrams of the apparatus.
The extent and significance of such losses must be evaluated on
an individual basis. If significant quantities of volatile carbon-
aceous materials are present or may be present in samples
Handbook for Monitoring Industrial Wastewater, U.S. Environment Protection
Agency, August 1973, pp. 5–10 to 5–12.
Instruments marketed by Coulometrics, Inc., a subsidiary of UIC Inc., P.O. Box
Van Hall, C. E., Barth, D., and Stenger, V. A., “Elimination of Carbonates from 563, Joliet, IL, 60434, or an equivalent, have been found satisfactory.
Aqueous Solutions Prior to Organic Carbon Determinations,” Analytical Chemistry,
Vol 37, 1965, pp. 769–771.
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
D 4129
FIG. 2 CO Evolution Apparatus
7.2 Sampling Devices— A spring-loaded .200-mL syringe 8.4 Scrubber Tubes and Catalyst Packings as well as in-
(carbon analyzer syringe) having an all metal tip and a 50 mm structions for their preparation are available from the equip-
long, 0.5-mm inside diameter needle with a square end is ment manufacturer. Fig. 1 illustrates the flow diagram and
recommended for water samples containing little or no particu- names the reagents used.
late matter. 8.5 Carbon Dioxide Coulometer Reagents—Cell solutions
7.3 Homogenizing Apparatus—A household blender with to absorb CO from the gas stream and convert it to a titratable
glass mixing chamber is generally satisfactory for homogeniz- acid and permit 100 % efficient coulometric titration.
ing immiscible phases in water. 8.6 Acid—Various acids may be used for acidification of
samples. Hydrochloric acid is recommended. Phosphoric and
sulfuric acids are suitable if they do not cause materials to
8. Reagents
precipitate from the sample. Nitric acid is not recommended
8.1 Purity of Reagents—Reagent grade chemicals shall be
because it may cause premature oxidation of organics in the
used in all tests. Unless otherwise indicated, it is intended that
sample.
all reagents shall conform to the specifications of the commit-
7 8.7 Organic Carbon Standard Solutions—Although the
tee on Analytical Reagents of the American Chemical Society.
method does not require sample standardization, proper opera-
Other grades may be used provided it is first ascertained that
tion of the instrument should be confirmed by injection of
the reagent is of sufficiently high purity to permit its use
standards of similar composition and concentration to the
without lessening the accuracy of the determination.
unknown. Standards should be stable water soluble compounds
8.2 Purity of Water— Unless otherwise indicated, reference
such as KHP or benzoic acid of suitable purity.
to water shall be understood to mean reagent water conforming
to the Specification D 1193, Type II. Where specified, carbon
9. Hazards
dioxide-free water is to be prepared by boiling distilled water
9.1 Injection of samples containing over 25 000 mg/L TOC
in a conical flask for 20 min. The boiled water is cooled in the
or 0.5 mL water may cause explosion of the combustion tube.
flask stoppered with a one-hole rubber stopper fitted to a soda
lime-Ascarite drying tube. For large (10 to 20 L) volumes of
10. Sampling
carbon dioxide-free water, the absorbed carbon dioxide may be
removed by inserting a fritted-glass gas-dispersion tube to the
10.1 Collect the sample in accordance with Practices
bottom of the container and vigorously bubbling nitrogen
D 3370 or other applicable ASTM method(s).
through the water for at least 1 h. Carbon dioxide-free water
10.2 Preservation:
may be stored if properly protected from atmospheric contami-
10.2.1 To preserve samples for this analysis, store or ship
nation.
samples in glass at or below 4°C. Caution— Head space in the
sample bottle or freezing the sample may contribute to the loss
NOTE 1—Glass containers are preferred for the storage of reagent water
of volatile organics from some samples.
and most standard solutions. It is necessary to provide protection against
changes in quality due to the absorption of gases or water vapor from the 10.3 For monitoring of waters containing solids or immis-
laboratory air. As volumes of fluid are withdrawn from the container, the
cible liquids of interest, use a mechanical homogenizer or
replacement air should be passed through a drying tube filled with equal
ultrasonic disintegrator to homogenize samples.
parts of 8 to 20-mesh soda lime, oxalic acid, and 4 to 8-mesh anhydrous
10.4 For waste water streams where carbon concentrations
calcium chloride, each product being separated from the other by a
are greater than the desired range of instrument operation,
glass-wool plug.
provide on-stream dilution of the sample if possible.
8.3 Gas Supply—Use oxygen of at least 99.6 % purity.
10.5 A1.1 gives additional guidelines for preparing heavily
contaminated water samples when using the sparge technique.
10.6 A1.2 gives additional guidelines for samples contain-
ing solids and immiscible liquids.
Syringes manufactured by Hamilton Co., P.O. Box 10030, Reno, NV 89510, or
an equivalent, have been found satisfactory for this purpose.
Reagent Chemicals, American Chemical Society Specifications, American
Chemical Society, Washington, DC. For suggestions on the testing of reagents not
listed by the American Chemical Society, see Analar Standards for Laboratory Satisfactory reagents available from Coulometrics, Inc., a subsidiary of UIC
Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia Inc., P.O. Box 563, Joliet, IL, 60434 use ethanolamine to absorb CO forming
and National Formulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville, hydroxethylcarbamic acid that is titrated coulometrically using a color indicator for
MD. end-point detecti
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