ASTM_D_4735_-_15.pdf

Designation:D473515Standard Test Method forDetermination of Trace Thiophene in Refined Benzene byGas Chromatography1This standard is issued under the fixed designation D4735;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.Scope*1.1 This test method covers the determination of thiophenein refined benzene in the range from 0.80 to 1.80 mg/kg for theFlame Photometric Detector(FPD),and from 0.14 to 2.61mg/kg for the Pulsed Flame Photometric Detector(PFPD).Forthe PFPD,the minimum level of quantitation(LOQ)is 0.14mg/kg and the minimum level of detection(LOD)is 0.04mg/kg,as described inASTM Research Report RR:D16-1038.2The range of the test method may be extended by modifyingthe sample injection volume,split ratios,calibration range,orsample dilution with thiophene-free solvent.1.2 This test method has been found applicable to benzenecharacteristic of the type described in Specifications D2359and D4734 and may be applicable to other types or grades ofbenzene only after the user has demonstrated that the procedurecan completely resolve thiophene from the other organiccontaminants contained in the sample.1.3 The following applies to all specified limits in this testmethod:for purposes of determining conformance to appli-cable specification using this test method,an observed value ora calculated value shall be rounded off“to the nearest unit”inthe last right-hand digit used in expressing the specificationlimit in accordance with the rounding-off method of PracticeE29.1.4 The values stated in SI units are to be regarded asstandard.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.For specific hazardstatements,see Section 7.2.Referenced Documents2.1 ASTM Standards:3D1193 Specification for Reagent WaterD2359 Specification for Refined Benzene-535D3437 Practice for Sampling and Handling Liquid CyclicProductsD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD4307 Practice for Preparation of Liquid Blends for Use asAnalytical StandardsD4734 Specification for Refined Benzene-545D6809 Guide for Quality Control and Quality AssuranceProcedures for Aromatic Hydrocarbons and Related Ma-terialsE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE260 Practice for Packed Column Gas ChromatographyE355 Practice for Gas Chromatography Terms and Relation-shipsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodE840 Practice for Using Flame Photometric Detectors in GasChromatographyE1510 Practice for Installing Fused Silica Open TubularCapillary Columns in Gas Chromatographs2.2 Other Document:OSHA Regulations,29 CFR paragraphs 1910.1000 and1910.120043.Summary of Test Method3.1 The thiophene concentration in refined benzene is de-termined at the milligram thiophene per kilogram sample level1This test method is under the jurisdiction of ASTM Committee D16 onAromatic Hydrocarbons and Related Chemicals and is the direct responsibility ofSubcommittee D16.04 on Instrumental Analysis.Current edition approved June 1,2015.Published July 2015.Originally approvedin 1987.Last previous edition approved in 2014 as D4735 09(2014).DOI:10.1520/D4735-15.2Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D16-1038.ContactASTM CustomerService at serviceastm.org.3For 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.4Available from U.S.Government Printing Office Superintendent of Documents,732 N.Capitol St.,NW,Mail Stop:SDE,Washington,DC 20401,http:/www.access.gpo.gov.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 using conventional gas-liquid chromatography with a flamephotometric detector(FPD)or pulsed flame photometric de-tector(PFPD).A reproducible volume of sample is injected.Quantitative results are obtained by the external standardtechnique using the measured peak area of thiophene.4.Significance and Use4.1 This test method is suitable for setting specifications onbenzene and for use as an internal quality control tool wherebenzene is either produced or used in a m