1、Designation:D115791(Reapproved 2019)Standard Test Method forTotal Inhibitor Content(TBC)of Light Hydrocarbons1,2This standard is issued under the fixed designation D1157;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of las
2、t 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 totalp-tertiary-butylcatechol inhibitor added to polymerization andrecycle grades
3、 of butadiene or to other C4hydrocarbonmixtures containing no phenolic material other than catechol orno oxidized phenolic material other than that derived fromoxidation of catechol.In general,all phenols and their quinoneoxidation products are included in the calculated catecholcontent.Small amount
4、s of polymer do not interfere.This testmethod is applicable over the range of TBC from 50 mg kg to500 mgkg.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of thesafety concern
5、s,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.1.4 This international standard was developed in accor-dance with internat
6、ionally 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:3D1265 Practi
7、ce for Sampling Liquefied Petroleum(LP)Gases,Manual Method3.Summary of Test Method3.1 The catechol is separated from the butadiene by evapo-ration.The residue is dissolved in water and an excess of ferricchloride is added.The intensity of the yellow-colored complexis compared in a photoelectric colo
8、rimeter with that producedby known concentrations of the catechol.4.Significance and Use4.1 p-tertiary-butylcatechol is commonly added to commer-cial butadiene in amounts of 50 mg kg to 250 mg kg as anoxidation inhibitor.This test method is suitable for use by bothproducers and users of butadiene wi
9、thin the limitations de-scribed in Section 1.5.Apparatus5.1 PhotometerA sensitive photoelectric photometer ca-pable of producing light of narrow spectral range that ispredominantly blue(425 nm).5.2 Graduates,100 mL.5.3 Volumetric Flasks,100 mL;or stoppered graduatedmixing cylinder,100 mL.5.4 Erlenme
10、yer Flasks,250 mL.5.5 Funnels,75 mm diameter.5.6 Pipet,5 mL.6.Reagents6.1 Purity of ReagentsReagent grade chemicals shall beused in all tests.Unless otherwise indicated,it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemic
11、al Society,where such specifications are available.4Other grades may beused,provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.1This test method is under the jurisdiction of ASTM Committee D02 onPetrole
12、um Products,Liquid Fuels,and Lubricantsand is the direct responsibility ofSubcommittee D02.D0.04 on C4 and C5 Hydrocarbons.Current edition approved Dec.1,2019.Published December 2019.Originallyapproved in 1951.Last previous edition approved in 2014 as D1157 91(2014).DOI:10.1520/D1157-91R19.2This tes
13、t method was derived from the method developed and cooperativelytested by the Butadiene Producers Committee on Specifications and Methods ofAnalysis of the Office of Rubber Reserve,which appears in the ButadieneLaboratory Manual as Method 2.1.9.1.3For referenced ASTM standards,visit the ASTM website
14、,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.4ACS Reagent Chemicals,Specifications and Procedures for Reagents andStandard-Grade Reference Materials,American Chemic
15、al Society,Washington,DC.For suggestions on the testing of reagents not listed by the American ChemicalSociety,see Analar Standards for Laboratory Chemicals,BDH Ltd.,Poole,Dorset,U.K.,and the United States Pharmacopeia and National Formulary,U.S.Pharma-copeial Convention,Inc.(USPC),Rockville,MD.Copy
16、right 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.16.2 Purity of WaterReferences to water shall be under-stood to mean distilled wat
