ASTM_D_7360_-_11.pdf

Designation:D736011Standard Test Method forAnalysis of Benzene by Gas Chromatography with ExternalCalibration1This standard is issued under the fixed designation D7360;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 This test method covers the determination of normallyoccurring trace impurities in,and the purity of,finishedbenzene by gas chromatography with external calibration.Asimilar test method,using the internal standard technique ofcalibration is Test Method D4492.1.2 This test method is applicable for nonaromatic hydro-carbon impurities at levels from 5 to 2000 mg/kg and forbenzene purities of 99.80 weight%or higher.1.3 This test method is applicable for aromatic impuritiesfrom 5 to 2000 mg/kg in benzene.1.4 This test method has been found applicable to hetero-atomic species such as 1,4-dioxane,from 10 to 2000 mg/kg inbenzene.1.5 The limit of detection for aromatic impurities is 0.9mg/kg,2.7 mg/kg for 1,4-dioxane and 1.1 mg/kg for methylcyclohexane.1.6 In determining the conformance of the test results usingthis method to applicable specifications,results shall berounded off in accordance with the rounding-off method ofPractice E29.1.7 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.8 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 9.2.Referenced Documents2.1 ASTM Standards:2D3437 Practice for Sampling and Handling Liquid CyclicProductsD3798 Test Method for Analysis of p-Xylene by Gas Chro-matography(Withdrawn 2009)3D4307 Practice for Preparation of Liquid Blends for Use asAnalytical StandardsD4492 Test Method for Analysis of Benzene by Gas Chro-matographyD4790 Terminology of Aromatic Hydrocarbons and RelatedChemicalsD6809 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-shipsE1510 Practice for Installing Fused Silica Open TubularCapillary Columns in Gas Chromatographs2.2 Other Document:4OSHA Regulations,29 CFR paragraphs 1910.1000 and1910.12003.Terminology3.1 See Terminology D4790 for definition of terms used inthis test method.1This test method is under the jurisdiction of ASTM Committee D16 onAromatic Hydrocarbons and Related Chemicals and is the direct responsibility ofSubcommittee D16.01 on Benzene,Toluene,Xylenes,Cyclohexane and TheirDerivatives.Current edition approved June 1,2011.Published July 2011.DOI:10.1520/D736011.2For 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.3The last approved version of this historical standard is referenced onwww.astm.org.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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.Summary of Test Method4.1 A repeatable volume of the specimen to be analyzed isprecisely injected into a gas chromatograph equipped with aflame ionization detector(FID)and a capillary column.4.2 The peak area of each impurity is measured.Theconcentration of each impurity is determined using responsefactor or the linear calibration curve of peak area versusconcentration.Purity is calculated by subtracting the sum ofthe impurities found from 100.00 weight%.The concentrationof impurities are reported in mg/kg.Purity of benzene isreported in weight percent.5.Significance and Use5.1 This test method is suitable for determining the concen-trations of known impurities in finished benzene and for use asan integral quality control tool where benzene is either pro-duced or used in a manufacturing procedure.It is generallyapplied to impurities such as nonaromatics containing ninecarbons or less,toluene,C8 aromatics,and 1,4-dioxane.5.2 Absolute purity cannot be determined if undetectedimpurities are present.6.Interferences6.1 Benzene is typically resolved from components withboiling points 138C that normally are found in purifiedbenzene.Components normally found in purified benzeneinclude nonaromati