ASTM_D_3371_-_95.pdf

Designation:D 3371 95Standard Test Method forNitriles in Aqueous Solution by Gas-LiquidChromatography1This standard is issued under the fixed designation D 3371;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.Scope1.1 This test method covers nitriles that can be separatedand detected quantitatively at a limit of approximately 1 mg/Lby aqueous injection on a selected gas-liquid chromatographiccolumn.1.2 This test method utilizes the procedures and precautionsas described in Practice D 2908.1.3 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.2.Referenced Documents2.1 ASTM Standards:D 1129 Terminology Relating to Water2D 2908 Practice for Measuring Volatile Organic Matter inWater by Aqueous-Injection Gas Chromatography33.Terminology3.1 DefinitionsFor definitions of terms used in this testmethod,refer to Terminology D 1129.4.Significance and Use4.1 Nitriles at concentrations of a few milligrams per litreare potentially toxic to aquatic life.Nitriles in waste waterdischarges should be detected and controlled.4.2 Gas-liquid chromatography(GLC)can detect and deter-mine mixtures of nitriles at levels where wet chemical proce-dures are not applicable.5.Special Comments5.1 It is recommended that samples that cannot be analyzedimmediately,be quick frozen for preservation.Samples shouldbe neutralized to pH 7 at the time of collection to minimizehydrolysis of the nitrile groups.5.2 Samples of nitriles to be employed as standards shouldbe considered to be unstable.Storage in a freezer is recom-mended.5.3 It is not always practical to translate operating condi-tions directly from one GLC instrument to another.An operatorshould optimize his instrument to a particular procedure,forexample,injection and detection temperature,flow rates,etc.6.Typical Chromatograms6.1 The following instrument parameters were used toobtain the typical chromatograms(See Fig.1 and Fig.2).6.1.1 Column18in.outside diameter stainless steel,8 ftlong packed with a porous styrene divinylbenzene polymer.NOTE1“Chromosorb”101,50/60 mesh,was used for the typicalchromatograms.6.1.2 Detector,flame ionization.6.1.3 Temperatures:Injection port240CDetector240COven,isothermal130COven,programmed at110C to max10C/minof 200C6.1.4 Carrier Gas,helium at 25 mL/min.6.1.5 Sample Size:isothermal 5 Lprogrammed 3 L6.1.6 Recorder,34in./min chart speed and 1 mV full-scaleresponse.6.2 Kovats Index Values:4CompoundsRelativeRetentionKovatsIndexAcetonitrile1.00470Acrylonitrile1.25512Proprionitrile1.67570Methoxyacetonitrile2.216355Butyronitrile2.50678Isovaleronitrile3.047405Valeronitrile3.38783Hexanenitrile4.259055Benzonitrile5.429907.Precision and Bias7.1 An interlaboratory study was conducted in 1972 withparticipation from four laboratories and seven operators.1This test method is under the jurisdiction of ASTM Committee D-19 on Waterand is the direct responsibility of Subcommittee D 19.06 on Methods for Analysisfor Organic Substances in Water.Current edition approved Dec.10,1995.Published February 1996.Originallypublished as D 3371 74 T.Last previous edition D 3371 79(1990).2Annual Book of ASTM Standards,Vol 11.01.3Annual Book of ASTM Standards,Vol 11.02.4Gas Chromatographic Data Compilation,ASTM AMD25A,1967.5Kovats index values estimated from relative retention data because standardcompound was not readily available.1AMERICAN SOCIETY FOR TESTING AND MATERIALS100 Barr Harbor Dr.,West Conshohocken,PA 19428Reprinted from the Annual Book of ASTM Standards.Copyright ASTMTriplicate analyses of three concentrations in distilled waterwere contributed by all operators;see Table 1 for statisticsfrom distilled water data.Three operators also did triplicaterecoveries of three concentrations spiked into a river water oftheir choice;see Table 2 for the statistics from the river waterrecovery data.7.2 The precision of this test method within the range from10 to 60 mg of standards/L in distilled water may be expressedas follows:CompoundAcetonitrileSt5 0.182x+0.194So5 0.023x+0.038ProprionitrileSt5 0.100 x 0.817So5 0.020 x+0.348MethoxyacetonitrileSt5 0.260 x+0.263So5 0.026x+0.671ButyronitrileSt5 0.107x 0.457So5 0.036x+0.202where:St5 overall precision,So5 single operator precision,andx5 concentration of the specification compound,mg/L.8.Keywords8.1 flame ionization;gas-liquid chromatography;GLC;isothermal chromatographic analysis;Kovats indexColumn Packing-Chromosorb 101,50/60 meshCarrier Gas-Helium at 25 mL/minTemperature-Isothermal operation of the column at 130CSample Size-5 microlitres containing 10 mg/L of each nitrileFI