1、Designation:D250488(Reapproved 2015)Standard Test Method forNoncondensable Gases in C2and Lighter HydrocarbonProducts by Gas Chromatography1This standard is issued under the fixed designation D2504;the number immediately following the designation indicates the year oforiginal adoption or,in the case
2、 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 hydrogen,nitrogen,oxygen,and carbon monoxide in the p
3、arts per millionvolume(ppmv)range in C2and lighter hydrocarbon products.This test method should be applicable to light hydrocarbonsother than ethylene,but the test program did not include them.1.2 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for
4、 informationonly.1.3 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.F
5、or some specifichazard statements,see the Annex A1.2.Referenced Documents2.1 ASTM Standards:2D2505 Test Method for Ethylene,Other Hydrocarbons,andCarbon Dioxide in High-Purity Ethylene by Gas Chroma-tographyE260 Practice for Packed Column Gas ChromatographyF307 Practice for Sampling Pressurized Gas
6、for Gas Analy-sis2.2 Other Standard:3Compressed GasAssociation Booklets G-4 and G-4.1 on theuse of oxygen.3.Summary of Test Method3.1 The sample is separated in a gas-solid chromatographicsystem using molecular sieves as the solid adsorbent.Theconcentration of the gases to be determined is calculate
7、d fromthe recorded peak heights or peak areas.Argon can be used asa carrier gas for the determination of hydrogen in concentra-tions below 100 ppmv.Argon,if present in the sample,interferes with oxygen determination.4.Significance and Use4.1 The presence of trace amounts of hydrogen,oxygen,andcarbon
8、 monoxide can have deleterious effects in certain pro-cesses using hydrocarbon products as feed stock.This testmethod is suitable for setting specifications,for use as aninternal quality control tool and for use in development orresearch work.5.Apparatus5.1 ChromatographAny chromatographic instrumen
9、thaving either a thermal conductivity or ionization detector withan overall sensitivity sufficient to detect 2 ppmv or less of thecompounds listed in the scope,with a peak height of at least2 mm without loss of resolution.5.2 DetectorsThermal ConductivityIf a methanation re-actor is used,a flame ion
10、ization detector is also required.Todetermine carbon monoxide with a flame ionization detector,amethanation reactor must be inserted between the column andthe detector and hydrogen added as a reduction gas.Details onthe preparation and use of the reactor are given in AppendixX1.5.3 Constant-Volume G
11、as Sampling Valve.5.4 ColumnAny column or set of columns that is capableof resolving the components listed in the scope can be used.Copper,stainless steel,or aluminum tubing may be used.Thecolumns chosen must afford a resolution such that the depth ofthe valleys ahead of the trace peak is no less th
12、an 50%of thetrace peak height.5.5 RecorderA recorder with a full-scale response of 2 sor less and a maximum rate of noise of 60.3%of full scale.5.6 OvenThe oven used for activating molecular sievesmust be maintained at 260 C to 288 C(500 F to 550 F)andshould be designed so that the gases may be disp
13、lacedcontinuously by a stream of inert gas.The oven may be athermostated piece of 1 in.pipe about 0.3 m(1 ft)in length.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.D0.02 on Ethyl
14、ene.Current edition approved June 1,2015.Published July 2015.Originally approvedin 1966.Last previous edition approved in 2010 as D2504 88(2010).DOI:10.1520/D2504-88R15.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Bo
15、ok of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from Compressed Gas Association(CGA),4221 Walney Rd.,5thFloor,Chantilly,VA 20151-2923,http:/.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-295
16、9.United States1 Electrical heating tapes or other means may be used for heatingprovided the heat is distributed uniformly.NOTE1The use of copper tubing is not recommended with samplescontaining acetylene as this could lead to the formation of potentiallyexplosive copper acetylide.6.Reagents and Materials6.1 Molecular Sieves,5A,13A,or 13XAny mesh sizes canbe used so long as sensitivity and resolution are maintained(see Note 2).If a 40 mesh to 60 mesh sieve size is desired,butis not available,it