ASTM D4129-2005(2012) Standard Test Method for Total and Organic Carbon in Water by High Temperature Oxidation and by Coulometric Detection 《用高温氧化法及库仑检测法对水中总碳量和有机碳含量的标准试验方法》.pdf

《ASTM D4129-2005(2012) Standard Test Method for Total and Organic Carbon in Water by High Temperature Oxidation and by Coulometric Detection 《用高温氧化法及库仑检测法对水中总碳量和有机碳含量的标准试验方法》.pdf》由会员分享，可在线阅读，更多相关《ASTM D4129-2005(2012) Standard Test Method for Total and Organic Carbon in Water by High Temperature Oxidation and by Coulometric Detection 《用高温氧化法及库仑检测法对水中总碳量和有机碳含量的标准试验方法》.pdf（7页珍藏版）》请在麦多课文档分享上搜索。

1、Designation: D4129 05 (Reapproved 2012)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 part

4、iculate 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 them

5、aximum 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

6、obtained 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 us

7、ers responsibility to ensure the validity of this testmethod on samples of other matrices.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practic

8、es 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:2D513 Test Methods for Total and Dissolved Carbon Diox-ide in WaterD1129 Terminology Relating to WaterD1193 Specification for

9、 Reagent WaterD3370 Practices for Sampling Water from Closed ConduitsD3856 Guide for Management Systems in LaboratoriesEngaged in Analysis of Water3D4210 Practice for Intralaboratory Quality Control Proce-dures and a Discussion on Reporting Low-Level Data43D5789 Practice for Writing Quality Control

10、Specificationsfor Standard Test Methods for Organic Constituents43. Terminology3.1 DefinitionsFor definitions of terms used in this testmethod, refer 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

11、 particlesor high-salt level a 0.200-mL portion is injected into thereaction zone. For samples containing solids or high salt levels,portions are placed in combustion boats containing tungstentrioxide (WO3) or quartz capillaries and introduced into thereaction zone using a ladle. In the reaction zon

12、e the heat,oxidation catalyst and oxygen atmosphere convert carbona-ceous matter to carbon dioxide (CO2). The oxygen gas streamsweeps the gaseous reaction products through a series ofscrubbers for potentially interfering gases and then to theabsorption/titration cell. The CO2is determined by automat

13、iccoulometric titration. Calibration by testing known carboncontent standards is not required, however, standards areanalyzed periodically to confirm proper operation.1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the direct responsibility of Subcommittee D19.06 on

14、Methods forAnalysis forOrganic Substances in Water.Current edition approved Jan. 1, 2012. Published January 2012. Originallyapproved in 1982. Last previous edition approved in 2005 as D4129 05. DOI:10.1520/D4129-05R12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact AS

15、TM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.4Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.1Copyright ASTM International, 100 Ba

16、rr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.2 Carbon dioxide is liberated from carbonates as well asfrom organic matter under the reaction conditions. Organiccarbon is determined by difference between the total carbonand the inorganic carbon determined separately

17、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, bicarbon-ates, and dissolved carbon dioxide prior to total carbondetermination. To determine organic carbon by difference theinorganic carbon is determined by acid release of

18、 carbondioxide from a portion of the sample or other methods as givenin Test Methods D513. For discussion of the limitations andguidelines for the use of the sparge technique see 5.4 and thepaper by Van Hall.54.3 Because of the various properties of carbon-containingcompounds in water, any prelimina

19、ry 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 dissolved carbonates and dissolved organic matter.Homogenizing permits determination of the carbon in in-soluble carbonates and insolub

20、le organic materials.5. Significance and Use5.1 This test method is necessary because of the need forrapid reliable tests for carbonaceous material in waters andsediments.5.2 It is used for determining the concentration of organiccarbon in water that comes from a variety of natural, domestic,and ind

21、ustrial sources. Typically, these measurements are usedto monitor organic pollutants in domestic and industrial wastewater.5.3 When a sample is homogenized so that particulate,immiscible phases, and dissolved carbon from both organicand inorganic sources is determined, the measurement is calledtotal

22、 carbon (TC). When inorganic carbon response is elimi-nated by removing the dissolved CO2prior to the analysis orthe dissolved CO2concentration subtracted from the totalcarbon concentration, the measurement is called total organiccarbon (TOC). When particulates and immiscible phases areremoved prior

23、 to analysis the measurement is called dissolvedcarbon (DC), or dissolved organic carbon (DOC) if inorganiccarbon response has been eliminated.5.4 Homogenizing or sparging of a sample, or both, maycause loss of volatile organics, thus yielding a negative error.The extent and significance of such los

24、ses must be evaluated onan individual basis. If significant quantities of volatile carbo-naceous materials are present or may be present in samplesorganic carbon should be determined by the difference betweenthe total carbon and the inorganic carbon concentrations. Whenorganic carbon determined both

25、 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-eters such as COD and BOD is described in the literature.66. Interferences6.1 Any acidic or basic gas formed in the oxidation of th

26、esample and not removed by the scrubbers will interfere withthe test. Potentially interfering gases that are removed by thescrubbers include hydrogen sulfide (H2S), hydrogen chloride(HCl), hydrogen bromide (HBr), hydrogen iodide (HI), sulfurdioxide (SO2), sulfur trioxide (SO3) free halogens, halogen

27、oxides, 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 for potentially interferinggases may vary with the type of samples being analyzed. If thescrubber capacity is exceeded it can be re

28、cognized 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 appearance changes in the scrubbers. Ifthe scrubber capacity is exceeded during an analysis thescrubbers should be replaced and the anal

29、ysis repeated.Samples containing all concentrations of the potentially inter-fering species can be analyzed if the analyst uses great care toensure that the scrubbers are and remain effective for hissamples. The frequency of replacing the scrubbers will dependon the nature of the samples.7. Apparatu

30、s7.1 Apparatus for total carbon, organic carbon, and inor-ganic carbon determinationscombustion furnace with gassupply, gas purification train, flow control, acid reaction train,5Van Hall, C. E., Barth, D., and Stenger, V. A., “Elimination of Carbonates fromAqueous Solutions Prior to Organic Carbon

31、Determinations,” Analytical Chemistry,Vol 37, 1965, pp. 769771.6Handbook for Monitoring Industrial Wastewater, U.S. Environment ProtectionAgency, August 1973, pp. 510 to 512.FIG. 1 Total Carbon and TOC ApparatusD4129 05 (2012)2and carbon dioxide coulometer.7Fig. 1 and Fig. 2 show blockdiagrams of th

32、e apparatus.7.2 Sampling Devices A spring-loaded .200-mL syringe8(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 containing little or no particu-late matter.7.3 Homogenizing ApparatusA household blende

33、r withglass mixing chamber is generally satisfactory for homogeniz-ing immiscible phases in water.8. Reagents8.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the commit-tee onAn

34、alytical Reagents of theAmerican Chemical Society.9Other 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 determination.8.2 Purity of Water Unless otherwise indicated, referenceto water shall be

35、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 adverselyaffecting the precision and bias of the test method. Type IIwater was

36、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 stoppered with aone-hole rubber stopper fitted to a soda lime-Ascarite dryingtube

37、. 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 through the waterfor at least 1 h. Carbon dioxide-free water may be stored ifproperl

38、y 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 absorption of gases or water vapor from thelaboratory air. As volumes of fluid are w

39、ithdrawn 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 from the other by aglass-wool plug.8.3 Gas SupplyUse oxygen of at least 99.6 %

40、 purity.8.4 Scrubber Tubes and Catalyst Packings as well as in-structions for their preparation are available from the equip-ment manufacturer.10Fig. 1 illustrates the flow diagram andnames the reagents used.8.5 Carbon Dioxide Coulometer ReagentsCell solutionsto absorb CO2from the gas stream and con

41、vert it to a titratableacid and permit 100 % efficient coulometric titration.108.6 AcidVarious acids may be used for acidification ofsamples. Hydrochloric acid is recommended. Phosphoric andsulfuric acids are suitable if they do not cause materials toprecipitate from the sample. Nitric acid is not r

42、ecommendedbecause 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 confirmed by injection ofstandards of similar composition and concentration to th

43、eunknown. 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/L TOCor 0.5 mL water may cause explosion of the combustion tube.10. Sampling10.1 Collect the sample in accordance with Practices D33

44、70or other applicable ASTM method(s).10.2 Preservation:10.2.1 To preserve samples for this analysis, store 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 wat

45、ers containing solids or immis-cible liquids of interest, use a mechanical homogenizer orultrasonic disintegrator 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 possi

46、ble.7Instruments marketed by Coulometrics, Inc., a subsidiary of UIC Inc., P.O. Box563, Joliet, IL, 60434, or an equivalent, have been found satisfactory.8Syringes manufactured by Hamilton Co., P.O. Box 10030, Reno, NV 89510, oran equivalent, have been found satisfactory for this purpose.9Reagent Ch

47、emicals, 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 Pharmacopeiaand Nati

48、onal Formulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville,MD.10Satisfactory 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 using a color i

49、ndicator forend-point detection.FIG. 2 CO2Evolution ApparatusD4129 05 (2012)310.5 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 to 80 to 100 mL/min. Set the readout to milligrams perlitre except when other than 0.200-mL samples are used inwhich case se