ASTM_D_7871_-_18.pdf

Designation:D787118Standard Test Method forAnalysis of Cyclohexane by Gas Chromatography(EffectiveCarbon Number)1This standard is issued under the fixed designation D7871;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 the purityof cyclohexane by gas chromatography.1.2 This test method has been found applicable to themeasurement of impurities such as those found in Table 1,which are impurities that may be found in cyclohexane.Theimpurities can be analyzed over a range of 1 to 400 mg/kg bythis method,but may be applicable to a wider range.1.3 The limit of detection is 1 mg/kg.1.4 In determining the conformance of the test results usingthis test method to applicable specifications,results shall berounded off in accordance with the rounding-off method ofPractice E29.1.5 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.6 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.For specific hazards statements,see Section 8.1.7 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:2D3437 Practice for Sampling and Handling Liquid CyclicProductsD4790 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 SpecificationsE355 Practice for Gas Chromatography Terms and Relation-shipsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodE1510 Practice for Installing Fused Silica Open TubularCapillary Columns in Gas Chromatographs2.2 Other Standards:3OSHA Regulations,29 CFR paragraphs 1910.1000 and1910.12003.Terminology3.1 See Terminology D4790 for definitions of terms used inthis test method.4.Summary of Test Method4.1 The specimen to be analyzed is injected into a gaschromatograph equipped with a flame ionization detector(FID)and a capillary column.The peak area of each component is1This test method is under the jurisdiction of ASTM Committee D16 onAromatic,Industrial,Specialty and Related Chemicals and is the direct responsi-bility of Subcommittee D16.01 on Benzene,Toluene,Xylenes,Cyclohexane andTheir Derivatives.Current edition approved Jan.1,2018.Published January 2018.Originallyapproved in 2013.Last previous edition approved in 2013 as D7871 13.DOI:10.1520/D7871-18.2For 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 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 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.1 measured and adjusted using effective carbon number(ECN)4response factors.The concentration of each component iscalculated based on its relative percentages of total adjustedpeak area and normalized to 100.0000%.5.Significance and Use5.1 This test method is suitable for setting specifications onthe materials referenced in Table 1 and for use as an internalquality control tool where cyclohexane is produced or is usedin a manufacturing process.It may also be used in developmentor research work involving cyclohexane.5.2 This test method is useful in determining the purity ofcyclohexane with normal impurities present.If extremely highboiling or unusual impurities are present in the cyclohexane,this test method would not necessarily detect them and thepurity calculation would be erroneous.6.Apparatus6.1 Gas ChromatographAny instrument having a flameionization detector t