1、Designation: D4129 05 (Reapproved 2013)Standard Test Method forTotal and Organic Carbon in Water by High TemperatureOxidation and by Coulometric Detection1This standard is issued under the fixed designation D4129; the number immediately following the designation indicates the year oforiginal adoptio
2、n or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of total andorganic carbon in wat
3、er and waste water, including brackishwaters and brines in the range from 2 to 20 000 mg/L.This testmethod has the advantages of a wide range of concentrationwhich may be determined without sample dilution and theprovision for boat or capillary introduction of samples contain-ing sediments and parti
4、culate matter where syringe injection isinappropriate.1.2 This procedure is applicable only to that carbonaceousmatter in the sample that can be introduced into the reactionzone. When syringe injection is used to introduce samples intothe combustion zone, the syringe needle opening size limits thema
5、ximum size of particles that can be present in samples.Sludge and sediment samples must be homogenized prior tosampling with a micropipetor or other appropriate sampler andladle introduction into the combustion zone is required.1.3 The precision and bias information reported in this testmethod was o
6、btained in collaborative testing that includedwaters of the following types: distilled, deionized, potable,natural, brine, municipal and industrial waste, and waterderived from oil shale retorting. Since the precision and biasinformation reported may not apply to waters of all matrices, itis the use
7、rs responsibility to ensure the validity of this testmethod on samples of other matrices.1.4 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.5 This standard does not purport to address all of thesafety concerns, if any, associ
8、ated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. For specificprecautionary statements, see 9.1 and 10.2.1.2. Referenced Documents2.1 ASTM Standards:2D
9、513 Test Methods for Total and Dissolved Carbon Dioxidein WaterD1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD3370 Practices for Sampling Water from Closed ConduitsD3856 Guide for Management Systems in LaboratoriesEngaged in Analysis of WaterD4210 Practice for Intralaborato
10、ry Quality Control Proce-dures and a Discussion on Reporting Low-Level Data(Withdrawn 2002)3D5789 Practice for Writing Quality Control Specificationsfor Standard Test Methods for Organic Constituents(Withdrawn 2002)33. Terminology3.1 DefinitionsFor definitions of terms used in this testmethod, refer
11、 to Terminology D1129.4. Summary of Test Method4.1 The sample is homogenized or diluted, or both, asnecessary. If the sample does not contain suspended particlesor high-salt level a 0.200-mL portion is injected into thereaction zone. For samples containing solids or high salt levels,portions are pla
12、ced in combustion boats containing tungstentrioxide (WO3) or quartz capillaries and introduced into thereaction zone using a ladle. In the reaction zone the heat,oxidation catalyst and oxygen atmosphere convert carbona-ceous matter to carbon dioxide (CO2). The oxygen gas streamsweeps the gaseous rea
13、ction products through a series ofscrubbers for potentially interfering gases and then to theabsorption/titration cell. The CO2is determined by automaticcoulometric titration. Calibration by testing known carboncontent standards is not required, however, standards areanalyzed periodically to confirm
14、 proper operation.1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the direct responsibility of Subcommittee D19.06 on Methods forAnalysis forOrganic Substances in Water.Current edition approved May 1, 2013. Published May 2013. Originallyapproved in 1982. Last previou
15、s edition approved in 2012 as D4129 05 (2012).DOI: 10.1520/D4129-05R13.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe AST
16、M website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14.2 Carbon dioxide is liberated from carbonates as well asfrom organic matter under the reac
17、tion conditions. Organiccarbon is determined by difference between the total carbonand the inorganic carbon determined separately or by acidify-ing a portion of the sample to a pH of 2 or less and spargingwith carbon dioxide-free gas to remove carbonates,bicarbonates, and dissolved carbon dioxide pr
18、ior to totalcarbon determination. To determine organic carbon by differ-ence the inorganic carbon is determined by acid release ofcarbon dioxide from a portion of the sample or other methodsas given in Test Methods D513. For discussion of the limita-tions and guidelines for the use of the sparge tec
19、hnique see 5.4and the paper by Van Hall.44.3 Because of the various properties of carbon-containingcompounds in water, any preliminary treatment of a sampleprior to injection dictates a definition of the carbon measured.Filtration of the sample prior to injection will limit the carbonmeasured to dis
20、solved carbonates and dissolved organic matter.Homogenizing permits determination of the carbon in in-soluble carbonates and insoluble organic materials.5. Significance and Use5.1 This test method is necessary because of the need forrapid reliable tests for carbonaceous material in waters andsedimen
21、ts.5.2 It is used for determining the concentration of organiccarbon in water that comes from a variety of natural, domestic,and industrial sources. Typically, these measurements are usedto monitor organic pollutants in domestic and industrial wastewater.5.3 When a sample is homogenized so that part
22、iculate,immiscible phases, and dissolved carbon from both organicand inorganic sources is determined, the measurement is calledtotal carbon (TC). When inorganic carbon response is elimi-nated by removing the dissolved CO2prior to the analysis orthe dissolved CO2concentration subtracted from the tota
23、lcarbon concentration, the measurement is called total organiccarbon (TOC). When particulates and immiscible phases areremoved prior to analysis the measurement is called dissolvedcarbon (DC), or dissolved organic carbon (DOC) if inorganiccarbon response has been eliminated.5.4 Homogenizing or sparg
24、ing of a sample, or both, maycause loss of volatile organics, thus yielding a negative error.The extent and significance of such losses must be evaluated onan individual basis. If significant quantities of volatile carbo-naceous materials are present or may be present in samplesorganic carbon should
25、 be determined by the difference betweenthe total carbon and the inorganic carbon concentrations. Whenorganic carbon determined both by difference and by spargingagree it is acceptable to determine organic carbon by spargingfor similar samples.5.5 The relationship of TOC to other water quality param
26、-eters such as COD and BOD is described in the literature.56. Interferences6.1 Any acidic or basic gas formed in the oxidation of thesample and not removed by the scrubbers will interfere withthe test. Potentially interfering gases that are removed by thescrubbers include hydrogen sulfide (H2S), hyd
27、rogen chloride(HCl), hydrogen bromide (HBr), hydrogen iodide (HI), sulfurdioxide (SO2), sulfur trioxide (SO3) free halogens, halogenoxides, and nitrogen oxides. Hydrogen fluoride (HF) may beremoved by bubbling the gas stream through water in the watervapor condenser.6.2 The capacity of the scrubbers
28、 for potentially interferinggases may vary with the type of samples being analyzed. If thescrubber capacity is exceeded it can be recognized by thetitration continuing beyond the normal analysis time at a higherrate than the blank and high results for known carbon contentstandards as well as by appe
29、arance changes in the scrubbers. Ifthe scrubber capacity is exceeded during an analysis thescrubbers should be replaced and the analysis repeated.Samples containing all concentrations of the potentially inter-fering species can be analyzed if the analyst uses great care toensure that the scrubbers a
30、re and remain effective for hissamples. The frequency of replacing the scrubbers will dependon the nature of the samples.7. Apparatus7.1 Apparatus for total carbon, organic carbon, and inor-ganic carbon determinationscombustion furnace with gassupply, gas purification train, flow control, acid react
31、ion train,and carbon dioxide coulometer.6Fig. 1 and Fig. 2 show blockdiagrams of the apparatus.7.2 Sampling Devices A spring-loaded .200-mL syringe7(carbon analyzer syringe) having an all metal tip and a 50 mmlong, 0.5-mm inside diameter needle with a square end isrecommended for water samples conta
32、ining little or no particu-late matter.7.3 Homogenizing ApparatusA household blender withglass mixing chamber is generally satisfactory for homogeniz-ing immiscible phases in water.4Van Hall, C. E., Barth, D., and Stenger, V.A., “Elimination of Carbonates fromAqueous Solutions Prior to Organic Carbo
33、n Determinations,” Analytical Chemistry,Vol 37, 1965, pp. 769771.5Handbook for Monitoring Industrial Wastewater, U.S. Environment ProtectionAgency, August 1973, pp. 510 to 512.6Instruments marketed by Coulometrics, Inc., a subsidiary of UIC Inc., P.O. Box563, Joliet, IL, 60434, or an equivalent, hav
34、e been found satisfactory.7Syringes manufactured by Hamilton Co., P.O. Box 10030, Reno, NV 89510, oran equivalent, have been found satisfactory for this purpose.D4129 05 (2013)28. Reagents8.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is inten
35、ded thatall reagents shall conform to the specifications of the commit-tee onAnalytical Reagents of theAmerican Chemical Society.8Other grades may be used provided it is first ascertained thatthe reagent is of sufficiently high purity to permit its usewithout lessening the accuracy of the determinat
36、ion.8.2 Purity of Water Unless otherwise indicated, referenceto water shall be understood to mean reagent water conformingto the Specification D1193, Type I. Other reagent water typesmay be used, provided it is first ascertained that the water is ofsufficiently high purity to permit its use without
37、adverselyaffecting the precision and bias of the test method. Type IIwater was specified at the time of round robin testing of thistest method. If necessary, carbon dioxide-free water is to beprepared by boiling distilled water in a conical flask for 20 min.The boiled water is cooled in the flask st
38、oppered with aone-hole rubber stopper fitted to a soda lime-Ascarite dryingtube. For large (10 to 20 L) volumes of carbon dioxide-freewater, the absorbed carbon dioxide may be removed byinserting a fritted-glass gas-dispersion tube to the bottom of thecontainer and vigorously bubbling nitrogen throu
39、gh the waterfor at least 1 h. Carbon dioxide-free water may be stored ifproperly protected from atmospheric contamination.NOTE 1Glass containers are preferred for the storage of reagent waterand most standard solutions. It is necessary to provide protection againstchanges in quality due to the absor
40、ption of gases or water vapor from thelaboratory air. As volumes of fluid are withdrawn from the container, thereplacement air should be passed through a drying tube filled with equalparts of 8 to 20-mesh soda lime, oxalic acid, and 4 to 8-mesh anhydrouscalcium chloride, each product being separated
41、 from the other by aglass-wool plug.8.3 Gas SupplyUse oxygen of at least 99.6 % purity.8.4 Scrubber Tubes and Catalyst Packings as well asinstructions for their preparation are available from the equip-ment manufacturer.9Fig. 1 illustrates the flow diagram andnames the reagents used.8.5 Carbon Dioxi
42、de Coulometer ReagentsCell solutionsto absorb CO2from the gas stream and convert it to a titratableacid and permit 100 % efficient coulometric titration.98.6 AcidVarious acids may be used for acidification ofsamples. Hydrochloric acid is recommended. Phosphoric andsulfuric acids are suitable if they
43、 do not cause materials toprecipitate from the sample. Nitric acid is not recommendedbecause it may cause premature oxidation of organics in thesample.8.7 Organic Carbon Standard SolutionsAlthough themethod does not require sample standardization, proper opera-tion of the instrument should be confir
44、med by injection ofstandards of similar composition and concentration to theunknown. Standards should be stable water soluble compoundssuch as KHP or benzoic acid of suitable purity.9. Hazards9.1 Injection of samples containing over 25 000 mg/LTOCor 0.5 mL water may cause explosion of the combustion
45、 tube.8Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Phar
46、macopeiaand National Formulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville,MD.9Satisfactory reagents available from Coulometrics, Inc., a subsidiary of UICInc., P.O. Box 563, Joliet, IL, 60434 use ethanolamine to absorb CO2forminghydroxethylcarbamic acid that is titrated coulometrically
47、using a color indicator forend-point detection.FIG. 1 Total Carbon and TOC ApparatusFIG. 2 CO2Evolution ApparatusD4129 05 (2013)310. Sampling10.1 Collect the sample in accordance with Practices D3370or other applicable ASTM method(s).10.2 Preservation:10.2.1 To preserve samples for this analysis, st
48、ore or shipsamples in glass at or below 4C. Caution Head space in thesample bottle or freezing the sample may contribute to the lossof volatile organics from some samples.10.3 For monitoring of waters containing solids or immis-cible liquids of interest, use a mechanical homogenizer orultrasonic dis
49、integrator to homogenize samples.10.4 For waste water streams where carbon concentrationsare greater than the desired range of instrument operation,provide on-stream dilution of the sample if possible.10.5 A1.1 gives additional guidelines for preparing heavilycontaminated water samples when using the sparge technique.10.6 A1.2 gives additional guidelines for samples contain-ing solids and immiscible liquids.11. Calibration and Standardization11.1 Set up the analyzer and fill coulometer cell in accor-dance with the manufacturers specifications. Adjust the gasflow
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