ASTM_D_6296_-_98_2013.pdf

Designation:D629698(Reapproved 2013)Standard Test Method forTotal Olefins in Spark-ignition Engine Fuels byMultidimensional Gas Chromatography1This standard is issued under the fixed designation D6296;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 provides for the quantitative determi-nation of total olefins in the C4to C10range in spark-ignitionengine fuels or related hydrocarbon streams,such as naphthasand cracked naphthas.Olefin concentrations in the range from0.2 to 5.0 liquid-volume%or mass%,or both,can bedetermined directly on the as-received sample whereas olefinsin samples containing higher concentrations are determinedafter appropriate sample dilution prior to analysis.1.2 This test method is applicable to samples containingalcohols and ethers;however,samples containing greater than15%alcohol must be diluted.Samples containing greater than5.0%ether must also be diluted to the 5.0%or less level,priorto analysis.When ethyl-tert-butylether is present,only olefinsin the C4to C9range can be determined.1.3 This test method can not be used to determine individualolefin components.1.4 This test method can not be used to determine olefinshaving higher carbon numbers than C10.NOTE1Precision was determined only on samples containing MTBEand ethanol.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 and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1319 Test Method for Hydrocarbon Types in Liquid Petro-leum Products by Fluorescent Indicator AdsorptionD4052 Test Method for Density,Relative Density,and APIGravity of Liquids by Digital Density MeterD4307 Practice for Preparation of Liquid Blends for Use asAnalytical StandardsD4815 Test Method for Determination of MTBE,ETBE,TAME,DIPE,tertiary-Amyl Alcohol and C1to C4Alco-hols in Gasoline by Gas ChromatographyD5599 Test Method for Determination of Oxygenates inGasoline by Gas Chromatography and Oxygen SelectiveFlame Ionization Detection3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 trap,na device utilized to selectively retain specificportions(individual or groups of hydrocarbons or oxygenates)of the test sample and to release the retained components byincreasing the trap temperature.3.2 Acronyms:3.2.1 ETBEethyl-tert-butylether.3.2.2 MTBEmethyl-tertbutylether.4.Summary of Test Method4.1 A reproducible 0.2-L volume of a representativesample,or a dilution thereof,is introduced into a computercontrolled gas chromatographic system3consisting of a series1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricantsand is the direct responsibility ofSubcommittee D02.04.0L on Gas Chromatography Methods.Current edition approved Oct.1,2013.Published October 2013.Originallyapproved in 1998.Last previous edition approved in 2008 as D6296 98(2008).DOI:10.1520/D6296-98R13.2For 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 sole source of supply of apparatus known to the committee at this time,theAC FTO Analyzer,is AC Analytical Controls,Inc.,3494 Progress Dr.,Bensalem,PA 19020.If you are aware of alternative suppliers,please provide this informationto ASTM Headquarters.Your comments will receive careful consideration at ameeting of the responsible technical committee,1which you may attend.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 of columns,traps,and switching valves operating at varioustemperatures.The valves are actuated at predetermined timesto direct portions of the sample to appropriate columns andtraps.The sample first passes through a polar column thatretains C12+hydrocarbons,all aromatics,C11+olefins,andsome alcohols,all of which are subsequently backflushed tovent.The fraction eluting from the polar column,whichcontains C11and lower boiling saturated hydrocarbons as wellas decene and lower boiling olefins,enters an ether/alcohol trapwhere the ethers and alcohols are selectively retained and alsosubsequently backflushed.The fraction eluting from the ether/alcohol trap,which consists of C11and lower boiling saturatedhydrocarbons and the olefins,enters an olefin trap.The olefinsare selectively retained while the saturated hydrocarbons elut