ASTM_E_1616_-_08.pdf

Designation:E161608Standard Test Method forAnalysis of Acetic Anhydride Using Gas Chromatography1This standard is issued under the fixed designation E1616;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 describes the determination of assayand impurities in acetic anhydride by gas chromatography.Theacetic anhydride should be at least 95%pure.1.2 The values stated in SI units are to be regarded asstandard.The values given in parentheses are for informationonly.1.3 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 hazardsstatements see Section 9.2.Referenced Documents2.1 ASTM Standards:2E355 Practice for Gas Chromatography Terms and Relation-ships3.Terminology3.1 DefinitionsFor definitions of terms used in this testmethod,see Practice E355.4.Summary of Test Method4.1 The sample is injected onto a gas chromatographiccolumn.The components are separated as they pass throughthe column with helium carrier gas,their presence in theeffluent is detected by a flame ionization detector,and recordedas a chromatogram.The concentrations of sample componentsare calculated as weight percentages using area normalization.5.Significance and Use5.1 This test method provides for the determination of assayand impurities in acetic anhydride.Acetic anhydride is used asan intermediate in many chemical processes.Its relativeconcentration affects the efficiency of these processes.This testmethod provides a test procedure for assay and impurityspecification acceptance as well as manufacturing control.6.Interferences6.1 This test method describes the chromatographic separa-tion of possible impurities in acetic anhydride.Other impuritiescould coelute with the known components and cause aninterference.Therefore,an efficient gas chromatographic col-umn in good condition should be used in order to ensure thenecessary chromatographic separations and proper peak shapesso that good quantitative data may be obtained.6.2 This analysis is based upon the assumption that allcomponents are eluted from the gas chromatographic column.7.Apparatus7.1 GasChromatographAnygaschromatographequipped with a flame ionization detector and a split injectionsystem for use with capillary columns that can be operated atthe conditions given in Table 1.7.2 ColumnThe column must give satisfactory resolutionand proper peak shapes for the components listed in Fig.1.Table 1 contains a description of a column that has been foundsatisfactory.7.3 Recorder/IntegratorElectronic integration is recom-mended for this analysis.7.4 Syringe,10-L capacity.8.Reagents8.1 Purity of ReagentsReagent grade chemicals shall beused in all tests.Unless otherwise indicated,it is intended thatall reagents conform to the specifications of the Committee onAnalytical Reagents of the American Chemical Society wheresuch specifications are available.3Other grades may be used,1This test method is under the jurisdiction of ASTM Committee E15 onIndustrial and Specialty Chemicalsand is the direct responsibility of SubcommitteeE15.02 on Product Standards.Current edition approved April 1,2008.Published May 2008.Originallyapproved in 1994.Last previous edition approved in 2002 as E161694(2002)1.DOI:10.1520/E1616-08.2For 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.3Reagent Chemicals,American Chemical Society Specifications,AmericanChemical Society,Washington,DC.For suggestions on the testing of reagents notlisted by the American Chemical Society,see Analar Standards for LaboratoryChemicals,BDH Ltd.,Poole,Dorset,U.K.,and the United States Pharmacopeiaand National Formulary,U.S.Pharmacopeial Convention,Inc.(USPC),Rockville,MD.*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 States1 provided it is first ascertained that the reagent is of sufficientlyhigh purity to permit its use without lessening the accuracy ofthe determination.8.2 High-Purity Acetic Anhydride(99.8%or GreaterPurity)It is important that the acetic anhydride used toprepare calibration standards be as pure as possible.If theacetic anhydride specified by this test method is not suitable forstandard preparation,it should be redistilled prior to use oranother source found.Note that American Chemical Societyreagent grade acetic anhydride may not be s