1、Designation: D 5373 02 (Reapproved 2007)Standard Test Methods forInstrumental Determination of Carbon, Hydrogen, andNitrogen in Laboratory Samples of Coal and Coke1This standard is issued under the fixed designation D 5373; the number immediately following the designation indicates the year oforigin
2、al adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 These test methods cover the instrumental determinationof carbon
3、, hydrogen, and nitrogen in laboratory samples of coaland coke prepared in accordance with Test Methods D 2013and D 346.1.2 Within the limitations outlined below, these test meth-ods are applicable to either the air-dry or moisture-freelaboratory sample, or both.1.2.1 For instrumental systems in whi
4、ch the moisture andwaters of hydration in the sample are liberated with (and onlywith) the oxidation products upon combustion, the analysescan be performed on a test specimen of the air-dry sample(Note 1). Concentrations determined on this air-dried basisrepresent the total carbon (including that pr
5、esent as carbonate),total hydrogen (including that present as water), and totalnitrogen.NOTE 1These systems are also satisfactory for determining thesubject materials in the moisture-free sample.1.2.2 For systems in which the moisture and hydrates areotherwise liberated, the analysis shall be perfor
6、med on themoisture-free sample. Values obtained on this basis representthe total carbon, organic hydrogen, and total nitrogen.1.3 These test methods can be used to provide for therequirements specified in Practice D 3176 for the ultimateanalysis.1.4 The values stated in SI units shall be regarded as
7、 thestandard.1.5 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 practices and determine the applica-bility of regulatory limitations prior to use. S
8、pecific precau-tionary statements are given in 8.3.1.2. Referenced Documents2.1 ASTM Standards:2D 346 Practice for Collection and Preparation of CokeSamples for Laboratory AnalysisD 2013 Practice for Preparing Coal Samples for AnalysisD 3173 Test Method for Moisture in theAnalysis Sample ofCoal and
9、CokeD 3174 Test Method forAsh in theAnalysis Sample of Coaland Coke from CoalD 3176 Practice for Ultimate Analysis of Coal and CokeD 3180 Practice for Calculating Coal and Coke Analysesfrom As-Determined to Different BasesD 4621 Guide for Quality Management in an OrganizationThat Samples or Tests Co
10、al and CokeD 5142 Test Methods for Proximate Analysis of the Analy-sis Sample of Coal and Coke by Instrumental Procedures3. Summary of Test Methods3.1 Carbon, hydrogen, and nitrogen are determined concur-rently in a single instrumental procedure. In some systems, theprocedure consists of simply weig
11、hing a test specimen, placingthe test portion into the instrument, and initiating the (subse-quently automatic) analytical process. In other systems, theanalytical process may be controlled manually to some degree.3.2 The actual process can vary substantially from instru-ment to instrument because a
12、 variety of means can be used toeffect the primary requirements of the test methods. These testmethods provide for the following: (1) conversion of thesubject materials in an oxygen stream in their entirety to carbondioxide, water vapor, nitrogen oxides, and ash, respectively;and (2) subsequent, qua
13、ntitative determination of the gases inan appropriate reference gas stream.1These test methods are under the jurisdiction ofASTM Committee D05 on Coaland Coke and are the direct responsibility of Subcommittee D05.21 on Methods ofAnalysis.Current edition approved May 1, 2007. Published May 2007. Orig
14、inallyapproved in 1993. Last previous edition approved in 2002 as D 537302.2For 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
15、 ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2.1 The conversion of the subject materials to theircorresponding gases occurs largely during combustion of thesample at an elevated temperature in an atmosphere of puri
16、fiedoxygen. The gases that are produced include the following:3.2.1.1 Carbon dioxide from the oxidation of organic andelemental carbon and the decomposition of carbonate minerals;3.2.1.2 Hydrogen halides from organic halides (and organichydrogen, as required);3.2.1.3 Water vapor from the oxidation o
17、f (the remaining)organic hydrogen and the liberation of moisture and waters ofhydration;3.2.1.4 Nitrogen and nitrogen oxides from the oxidation oforganic nitrogen and the decomposition of nitrates; and3.2.1.5 Sulfur oxides from the oxidation of organic sulfur,and the decomposition of sulfide and sul
18、fate minerals.(1) In some systems, sulfurous and sulfuric acids can also beobtained from a combination of the sulfur oxides and the watervapor.3.2.2 For hydrogen and nitrogen, the required conversion iscompleted in a two-step process consisting of the following:3.2.2.1 Removal of the halides and sul
19、fur oxides and libera-tion of the associated hydrogen (as water), by conducting thecombustion gases through a series of absorption traps contain-ing appropriate absorbing materials.3.2.2.2 Reduction of the nitrogen oxides to elemental nitro-gen (see Note 2) by passing the resultant gases over copper
20、 atan elevated temperature. The carbon dioxide, water vapor, andnitrogen may then be determined via one of several satisfactorydetection schemes.NOTE 2In this process, residual oxygen is also removed.3.2.3 In one configuration, the gases are conducted througha series of thermal conductivity detector
21、s and gas absorbersaligned so that, at the water vapor detector level, the gases passthrough the sample side of the detector, a water vapor absorber,and the reference side of the detector. At the carbon dioxidedetector level, the gases are then conducted through the sampleside of the detector, a car
22、bon dioxide absorber, and thereference side of the detector. Finally, the resultant gases,which contain only nitrogen and the carrier gas, pass throughthe sample side of the nitrogen detector and are vented. At thisdetector level, high-purity carrier gas is used as the referencegas. In these ways, t
23、he detectors determine the thermalconductivities solely of the specified components.3.2.4 In a second configuration, the carbon dioxide andwater vapor are determined by infrared detection, using analiquot of the combustion gases from which only the halidesand sulfur oxides have been removed. These d
24、etectors deter-mine the infrared absorption of the pertinent gases at precisewavelength windows so that the absorbances result from onlythe specified components. In these systems, nitrogen is deter-mined by thermal conductivity, using a second aliquot of thegases, additionally treated to also reduce
25、 the nitrogen oxides tonitrogen and to remove the residual oxygen, carbon dioxide,and water vapor.3.2.5 In a third configuration, which is essentially a modi-fied gas chromatographic system, the nitrogen, carbon dioxide,and water vapor in the treated combustion gases are elutedfrom a chromatographic
26、 column and determined (at appropri-ate retention times) by thermal conductivity detection.3.3 In all cases, the concentrations of carbon, hydrogen, andnitrogen are calculated as functions of the following:3.3.1 Measured instrumental responses,3.3.2 Values for response per unit mass for the elements
27、(established via instrument calibration), and3.3.3 Mass of the sample.3.4 Or to the following: the instrument response is propor-tional to the gas density, which has been calibrated against agas density of known concentration.3.5 A capability for performing these computations auto-matically can be i
28、ncluded in the instrumentation used for thesetest methods.4. Significance and Use4.1 Carbon and hydrogen values are used to determine theamount of oxygen (air) required in combustion processes andfor the calculations of efficiency of combustion processes.4.2 Carbon and hydrogen determinations are us
29、ed in mate-rial balance calculations on coal conversion processes; also,one or the other is used frequently in correlations of chemicaland physical properties, such as yields of products in liquefac-tion reactivity in gasification and the density and porosity ofcoal.4.3 Nitrogen data are required to
30、 fulfill the requirements ofthe ultimate analysis, Practice D 3176. Also, the data obtainedcan be used to evaluate the potential formation of nitrogenoxides as a source of atmospheric pollution.4.4 Nitrogen data are used for comparing coals and inresearch. If the oxygen content of coal is estimated
31、bydifference, it is necessary to make a nitrogen determination.5. Apparatus5.1 Because a variety of instrumental components andconfigurations can be used satisfactorily for these test methods,no specifications are presented here with respect to overallsystem design.5.2 Functionally, however, the fol
32、lowing requirements arespecified for all approved instruments (Note 3):NOTE 3The approval of an instrument with respect to these functionsis paramount to these test methods, since such approval tacitly providesapproval of both the materials and the procedures used with the system toprovide for these
33、 functions.5.2.1 The conditions for combustion of the sample shall besuch that (for the full range of applicable samples) the subjectcomponents shall be converted completely to carbon dioxide,water vapor (except for hydrogen associated with volatilehalides), and nitrogen or nitrogen oxides. Generall
34、y, instru-mental conditions that effect complete combustion include (1)availability of the oxidant, (2) temperature, and (3) time.5.2.2 Representative aliquots of the combustion gases shallthen be treated for the following reasons:5.2.2.1 To liberate (as water vapor) hydrogen present ashydrogen hali
35、des and sulfur oxyacids; and5.2.2.2 To reduce (to the element) nitrogen present asnitrogen oxides.(1) The water vapor and nitrogen so obtained shall beincluded with the materials originally present in these aliquots.D 5373 02 (2007)25.2.3 Additional treatment of the test specimens (prior todetection
36、) depends on the detection scheme used for theinstrument (Note 4).NOTE 4The additional treatments can be provided by the instrumentalcomponents used to satisfy 5.2.2.5.2.3.1 For the configuration described in 3.2.3, the halidesproper, sulfur oxides, and residual oxygen shall be removedfrom the singl
37、e test specimen in which the water vapor, carbondioxide, and nitrogen are determined sequentially.5.2.3.2 For the configuration described in 3.2.4, the testspecimen in which the water vapor and carbon dioxide aredetermined, only the halides and sulfur oxides shall be re-moved from the gas stream in
38、which the water vapor andcarbon dioxide are determined. For combusted gases in whichthe nitrogen is determined, the water, carbon dioxide, andresidual oxygen shall also be removed.5.2.3.3 For the configuration described in 3.2.5, the halidesand sulfur oxides shall be removed from the combusted gases
39、obtained from the single test specimen.5.2.4 The detection system (in its full scope) shall determinethe analytical gases individually and without interference.Additionally, for each analyte, either of the following applies:5.2.4.1 The detectors themselves shall provide linear re-sponses that correl
40、ate directly to concentration over the fullrange of possible concentrations from the applicable samples,or5.2.4.2 The system shall include provisions for evaluatingnonlinear responses appropriately so that the nonlinear re-sponses can be correlated accurately with these concentrations.(1) Such provi
41、sions can be integral to the instrumentation,or they can be provided by (auxiliary) computation schemes.5.2.5 Finally, except for those systems in which the concen-tration data are output directly, the instrument shall include anappropriate readout device for the detector responses.6. Reagents6.1 Pu
42、rity 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 on Analytical Reagents of the American Chemical Society,where such specifications are available.3Other grades may beuse
43、d, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.6.2 Helium, Carrier Gas, as specified by the instrumentmanufacturer.6.3 Oxygen, as specified by the instrument manufacturer.6.4 Additional Reagents,
44、 as specified by the instrumentmanufacturer. This specification refers to the reagents used toprovide for the functional requirements cited in 5.2.2-5.2.3.3.These reagents can vary substantially for different instruments;in all cases, however, for systems that are functionally satis-factory (and the
45、refore approved), the reagents recommendedby the manufacturer are also tacitly approved. Consequently,these reagents shall be those recommended by the manufac-turer.7. Preparation of Analysis Sample7.1 The samples shall initially be prepared in accordancewith Test Methods D 2013 or D 346.7.2 If requ
46、ired by characteristics of the instrumental system,reduce the air-dry samples (7.1) typically to pass 75 m (No.200 U.S.A. Standard Sieve Series) to obtain test units of theanalysis sample in the size range recommended by the instru-ment manufacturer. If required by characteristics of the instru-ment
47、al system, as specified in 1.2.2, treat the test specimens inaccordance with Test Method D 3173 to provide moisture-freematerials solely appropriate for these systems. In this and allsubsequent sample handling steps, exercise care to minimizechanges in moisture content resulting from exposure to the
48、atmosphere.8. Instrument Preparation8.1 Assemble the instrumental system in accordance withthe manufacturers instructions.8.2 Adjustment of Response of Measurement SystemWeigh an appropriate test portion of standard reference mate-rial (SRM), calibrating agent, or reference coal. Analyze thetest por
49、tion (see 9.1). Repeat this procedure. Adjust instrumentresponse, as recommended by the manufacturer, until theabsence of drift is indicated.8.3 CalibrationSelect coal SRMs or other calibratingagents and materials specified by the manufacturer that havecertified carbon, hydrogen, and nitrogen values in the range ofsamples to be analyzed.At least three such SRMs or calibratingagents are recommended for each range of carbon, hydrogen,and nitrogen values to be tested. When possible, two of theSRMs or calibrating agents shall bracket the range of carbon,hydrogen, and nitrogen to
