ASTM_D_7892_-_22.pdf

Designation:D789222Standard Test Method forDetermination of Total Organic Halides,Total Non-MethaneHydrocarbons,and Formaldehyde in Hydrogen Fuel by GasChromatography/Mass Spectrometry1This standard is issued under the fixed designation D7892;the number immediately following the designation indicates the year oforiginal adoption 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 The gas chromatography/mass spectrometry(GC/MS)procedure described in this test method is used to determineconcentrations of total organic halides and total non-methanehydrocarbons(TNMHC)in hydrogen by measurement ofindividual target halocarbons(Table 1)and hydrocarbons(including formaldehyde,Table 1 and Table 2),respectively.1.2 Mention of trade names in this test method does notconstitute endorsement or recommendation for use.Othermanufacturers equipment or equipment models can be used.1.3 UnitsThe values stated in SI units are to be regardedas standard.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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D4150 Terminology Relating to Gaseous FuelsD7606 Practice for Sampling of High Pressure Hydrogenand Related Fuel Cell Feed Gases2.2 SAE Standard:3SAE J2719 Hydrogen Fuel Quality for Fuel Cell Vehicles3.Terminology3.1 DefinitionsFor definitions of general terms used inD03 Gaseous Fuels standards,refer to Terminology D4150.3.2 Abbreviations:3.2.1 GCgas chromatograph3.2.2 m/emass to charge ratio3.2.3 MSmass spectrometer3.2.4 ppb(v)parts per billion as a volume3.2.5 ppm(v)parts per million as a volume3.2.6 UHPultra high purity4.Summary of Test Method4.1 The target compounds in Table 1 and Table 2,whichmay be contained in a 400 mL hydrogen sample,are cryogeni-cally frozen or concentrated onto a glass bead trap at-150 C.The target compounds are slowly desorbed by warming to 10C and transferred to a Tenax trap cooled to-60 C usingdesorption flow rate of 10 mL/min.This process leaves waterin the glass bead trap and dehydrates the sample.The Tenaxtrap is then desorbed by heating to 180 C and the targetcompounds cyro-focused at-170 C at the entrance to a GCcolumn(see 6.5).The cyro-focusing section is then rapidlyheated up to 80 C to release the cryo-focused targetcompounds,which are eventually eluted from the column andanalyzed using a mass spectrometer scanning from m/e 23 to100 for initial 4.5 min and from m/e 34 to 550 the remaininganalytical time.The retention times of the target compoundsare listed in Table 1 and Table 2 under the chromatographicconditions in 6.5.5.Significance and Use5.1 Low operating temperature fuel cells such as PEMFCsrequire high purity hydrogen for optimal performance and1This test method is under the jurisdiction ofASTM Committee D03 on GaseousFuels and is the direct responsibility of Subcommittee D03.14 on Hydrogen andFuel Cells.Current edition approved June 1,2022.Published July 2022.Originally approvedin 2015.Last previous edition approved in 2015 as D7892 15.DOI:10.1520/D7892-22.2For 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 ASTM website.3Available from SAE International(SAE),400 Commonwealth Dr.,Warrendale,PA 15096,http:/www.sae.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1TABLE 1 Organic HalidesTarget CompoundsFormulasMWBPCMPCCAS No.Retention Time(min)1,1,1-TrichloroethaneC2H3Cl3133.474-3371-55-68.8761,1,2,2-TetrachloroethaneC2H2Cl4167.9147-4479-34-514.6271,1,2-TrichloroethaneC2H3Cl3133.4114-3779-00-511.6071,2-DibromoethaneC2H4Br2187.913210106-93-412.5551,1-DichloroethaneC2H4Cl29957-9775-34-37.0341,1-DichloroetheneC2H2Cl296.932-12275-35-45.9271,2,4-TrichlorobenzeneC6H3Cl3181.521417120-82-119.7951,2,3,4-tetrachlorohexafluorobutaneC4Cl4F6303.41340 dl;73 meso375-45-113.0081,2-DichloroethaneC2H4Cl29984-35107-