ASTM_D_3797_-_04.pdf

Designation:D 3797 04Standard Test Method forAnalysis ofo-Xylene by Gas Chromatography1This standard is issued under the fixed designation D 3797;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(e)indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method covers the analysis of normally occur-ring impurities in,and the purity of,o-xylene by gas chroma-tography.Impurities determined include nonaromatic hydro-carbons,benzene,toluene,p-and m-xylenes,cumene,styrene,and ethylbenzene.1.2 This test method is applicable for impurities at concen-trations from 0.001 to 2.000%and for o-xylene purities of98%or higher.1.3 The following applies to all specified limits in thisstandard:for purposes of determining conformance with thisstandard,an observed value or a calculated value shall berounded off“to the nearest unit”in the last right-hand digitused in expressing the specification limit,in accordance withthe rounding-off method of Practice E 29.1.4 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 a specifichazard statement,see Section 8.2.Referenced Documents2.1 ASTM Standards:2D 3437 Practice for Sampling and Handling Liquid CyclicProductsD 4307 Practice for Preparation of Liquid Blends for Use asAnalytical StandardsD 4790 Terminology of Aromatic Hydrocarbons and Re-lated ChemicalsE 29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE 355 Practice for Gas Chromatography Terms and Rela-tionshipsE 1510 Practice for Installing Fused Silica Open TubularCapillary Columns in Gas Chromatographs2.2Other Documents:OSHA Regulations,29 CFR,paragraphs 1910.1000 and1910.120033.Terminology3.1 Definitions:3.1.1 For definition of terms used in this test method seeTerminology D 4790.4.Summary of Test Method4.1 A known amount of internal standard is added to thesample.Agas chromatograph equipped with a flame ionizationdetector and a polar-fused silica capillary column is used forthe analysis.The impurities are measured relative to theinternal standard.To calculate o-Xylene purity subtract theimpurities found from 100.00%.5.Significance and Use5.1 This test method is suitable for setting specifications ono-xylene and for use as an internal quality control tool whereo-xylene is used in a manufacturing process.It may be used indevelopment or research work involving o-xylene.5.2 Purity is commonly reported by subtracting the deter-mined expected impurities from 100%.Absolute purity cannotbe determined if unknown impurities are present.6.Apparatus6.1 Gas ChromatographyAny gas chromatograph havinga flame ionization detector and a splitter injector suitable foruse with a fused-silica capillary column may be used,providedthe system has sufficient sensitivity to obtain a minimum peakheight response of 0.1 mV for 0.010%internal standard whenoperated at the stated conditions.Background noise at theseconditions is not to exceed 3 V.6.2 Chromatographic Column,fused silica capillary,60-mlong,0.32-mm inside diameter,internally coated to a 0.5-mthickness with a bonded(cross-linked)polyethylene glycol.Other columns may be used after it has been established thatsuch column is capable of separating all major impurities and1This test method is under the jurisdiction of ASTM Committee D16 onAromatic Hydrocarbons and Related Chemicals and is the direct responsibility ofSubcommittee D16.01 on Benzene,Toluene,Xylenes,Cyclohexane and TheirDerivatives.Current edition approved Jan.1,2004.Published January 2004.Originallyapproved in 1979.Last previous edition approved in 2003 as D 3797 03.2For 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 20401.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.the internal standard from the o-xylene under operating con-ditions appropriate for the column.6.3 Recorder,optional.6.4 Electronic integration with tangent capabilities(re-quired).6.5 Microsyringes,10-L,and 50-L.6.6 Volumetric Flask,50-mL.7.Reagents and Materials7.1 Carrier Gas,hydrogen or helium,99.999%minimumpurity.Oxygen content in carrier less than 1 ppm(less than 0.5ppm preferred).Purify to remove hydrocarbons and water.7.2 Compressed Air,99.999%minimum purity.