ASTM_D_1492_-_21.pdf

Designation:D149221Standard Test Method forBromine Index of Aromatic Hydrocarbons by CoulometricTitration1This standard is issued under the fixed designation D1492;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 BromineIndex in aromatic hydrocarbons,their derivatives,and relatedchemicals.1.2 This test method is applicable to samples with BromineIndex concentrations to 100 Bromine Index.The limit ofdetection(LOD)is for 1.5 Bromine Index and the limit ofquantitation(LOQ)is 4.9 Bromine Index.NOTE1LOD and LOQ were calculated using data from the D16 PTPprogram.This estimate of LOD includes within-lab variability.1.3 The following applies for the purposes of determiningthe conformance of the test results using this test method toapplicable specifications,results shall be rounded off in accor-dance with the rounding-off method of Practice E29.1.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.For specific hazard statements,see Section 8.1.6 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:2D891 Test Methods for Specific Gravity,Apparent,of LiquidIndustrial ChemicalsD1193 Specification for Reagent WaterD3437 Practice for Sampling and Handling Liquid CyclicProductsD3505 Test Method for Density or Relative Density of PureLiquid ChemicalsD4052 Test Method for Density,Relative Density,and APIGravity of Liquids by Digital Density MeterD5776 Test Method for Bromine Index of Aromatic Hydro-carbons by Electrometric TitrationD6809 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 SpecificationsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method2.2 Other Document:OSHA Regulations,29 CFR paragraphs 1910.1000 and1910.120033.Terminology3.1 Definitions:3.1.1 bromine index(B),nthe number of milligrams(mg)of bromine consumed by 100 g of sample under givenconditions(mg-Br/100 g).4.Summary of Test Method4.1 The specimen is added to a solvent and titrated withelectrolytically generated bromine at room temperature.The1This test method is under the jurisdiction of ASTM Committee D16 onAromatic,Industrial,Specialty and Related Chemicals and is the direct responsi-bility of Subcommittee D16.04 on Instrumental Analysis.Current edition approved Nov.1,2021.Published January 2022.Originallyapproved in 1957.Last previous edition approved in 2013 as D1492 13.DOI:10.1520/D1492-21.2For 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.1end point is determined by a dead-stop method.The time oftitration is proportional to the bromine added to the specimen.5.Significance and Use5.1 This test method is useful as an internal quality controltool,and for use in development or research work on industrialaromatic hydrocarbons and related materials.This test methodgives a broad indication of olefinic content.It will notdifferentiate between the types of aliphatic unsaturation.6.Apparatus6.1 Amperometric-Coulometric Apparatus,automatic,suit-able for bromine index titrations with variable generatorcurrent and timer.A typical circuit diagram of suitable equip-ment is shown in Fig.1.6.2 Syringe,2 mL with needle an