EPA Method 8031 Acrylonitrile by Gas Chromatography - Revision 0
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ID： |
8BD9DEDD6A1243D4982C853907856800 |
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文件大小(MB)： |
0.03 |
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页数： |
7 |
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文件格式： |
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日期： |
2003-1-16 |
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文本摘录（文本识别可能有误，但文件阅览显示及打印正常，pdf文件可进行文字搜索定位）：
CD-ROM 8031 - 1 Revision 0,September 1994,METHOD 8031,ACRYLONITRILE BY GAS CHROMATOGRAPHY,1.0 SCOPE AND APPLICATION,1.1 Method 8031 is used to determine the concentration of acrylonitrile,in water. This method may also be applicable to other matrices. The following,compound can be determined by this method:,______________________________________________________________________________,Compound Name CAS No.a,Acrylonitrile 107-13-1,______________________________________________________________________________,a Chemical Abstract Services Registry Number.,1.2 The estimated quantitation limit of Method 8031 for determining the,concentration of acrylonitrile in water is approximately 10 μg/L.,1.3 This method is restricted to use by or under the supervision of,analysts experienced in the use of gas chromatographs and skilled in the,interpretation of gas chromatograms. Each analyst must demonstrate the ability,to generate acceptable results with this method.,2.0 SUMMARY OF METHOD,2.1 A measured sample volume is micro-extracted with methyl tert-butyl,ether. The extract is separated by gas chromatography and measured with a,Nitrogen/Phosphorus detector.,3.0 INTERFERENCES,3.1 Method interferences may be caused by contaminants in solvents,reagents, glassware, and other sample processing hardware that leads to discrete,artifacts and/or elevated baselines in gas chromatograms. All of these materials,must be routinely demonstrated to be free from interferences under the conditions,of the analysis by running laboratory reagent blanks.,3.2 Samples can be contaminated by diffusion of volatile organics around,the septum seal into the sample during handling and storage. A field blank,should be prepared from organic-free reagent water and carried through the,sampling and sample handling protocol to serve as a check on such contamination.,3.3 Contamination by carryover can occur whenever high-concentration and,low-concentration samples are sequentially analyzed. To reduce carryover, the,CD-ROM 8031 - 2 Revision 0,September 1994,sample syringe must be rinsed out between samples with solvent. Whenever an,unusually concentrated sample is encountered, it should be followed by the,analysis of solvent to check for cross contamination.,4.0 APPARATUS AND MATERIALS,4.1 Gas chromatograph system,4.1.1 Gas chromatograph, analytical system complete with gas,chromatograph suitable for on-column injections and all required,accessories, including detector, analytical columns, recorder, gases, and,syringes. A data system for measuring peak heights and/or peak areas is,recommended.,4.1.2 Column: Porapak Q - 6 ft., 80/10 Mesh, glass column, or,equivalent.,4.1.3 Nitrogen/Phosphorus detector.,4.2 Materials,4.2.1 Grab sample bottles - 40 mL VOA bottles.,4.2.2 Mixing bottles - 90 mL bottle with a Teflon lined cap.,4.2.3 Syringes - 10 μL and 50 μL.,4.2.4 Volumetric flask (Class A) - 100 mL.,4.2.5 Graduated cylinder - 50 mL.,4.2.6 Pipet (Class A) - 5, 15, and 50 mL.,4.2.7 Vials - 10 mL.,4.3 Preparation,4.3.1 Prepare all materials to be used as described in Chapter 4 for,volatile organics.,5.0 REAGENTS,5.1 Reagent grade chemicals shall be used in all tests. Unless otherwise,indicated, it is intended that all reagents shall conform to the specifications,of the Committee on Analytical Reagents of the American Chemical Society, where,such specifications are available. Other grades may be used, provided it is first,ascertained that the reagent is of sufficiently high purity to permit its use,without lessening the accuracy of the determination.,CD-ROM 8031 - 3 Revision 0,September 1994,5.2 General,5.2.1 Methanol, CH3OH - Pesticide quality, or equivalent.,5.2.2 Organic-free reagent water. All references to water in this,method refer to organic-free reagent water, as defined in Chapter One.,5.2.3 Methyl tert-butyl ether, CH3Ot-C4H9 - Pesticide quality, or,equivalent.,5.2.4 Acrylonitrile, H2C:CHCN, 98%.,5.3 Stock standard solution,5.3.1 Stock standard solutions - Can be prepared from pure standard,materials or can be purchased as certified solutions. Prepare stock,standards in organic-free reagent water using assayed liquids.,5.3.2 The stock standard solution may be prepared by volume or by,weight. Stock solutions must be replaced after one year, or sooner if,comparison with the check standards indicates a problem.,CAUTION: Acrylonitrile is toxic. Standard preparation should be,performed in a laboratory fume hood.,5.3.2.1 To prepare the stock standard solution by volume:,inject 10 μL of acrylonitrile (98%) into a 100 mL volumetric flask,with a syringe. Make up to volume with methanol.,5.3.2.2 To prepare the stock standard solut……
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