EPA Method 8330 Nitroaromatics and Nitramines by High Performance Liquid Chromatography (HPLC) - Revision 0
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ID： |
B581AC66EC464E1CA1D04182A65F8969 |
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文件大小(MB)： |
0.18 |
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页数： |
21 |
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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 8330 - 1 Revision 0,September 1994,METHOD 8330,NITROAROMATICS AND NITRAMINES BY HIGH,PERFORMANCE LIQUID CHROMATOGRAPHY (HPLC),1.0 SCOPE AND APPLICATION,1.1 Method 8330 is intended for the trace analysis of explosives residues,by high performance liquid chromatography using a UV detector. This method is,used to determine the concentration of the following compounds in a water, soil,or sediment matrix:,Compound Abbreviation CAS Noa,Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine HMX 2691-41-0,Hexahydro-1,3,5-trinitro-1,3,5-triazine RDX 121-82-4,1,3,5-Trinitrobenzene 1,3,5-TNB 99-35-4,1,3-Dinitrobenzene 1,3-DNB 99-65-0,Methyl-2,4,6-trinitrophenylnitramine Tetryl 479-45-8,Nitrobenzene NB 98-95-3,2,4,6-Trinitrotoluene 2,4,6-TNT 118-96-7,4-Amino-2,6-dinitrotoluene 4-Am-DNT 1946-51-0,2-Amino-4, 6-dinitrotoluene 2-Am-DNT 355-72-78-2,2,4-Dinitrotoluene 2,4-DNT 121-14-2,2,6-Dinitrotoluene 2,6-DNT 606-20-2,2-Nitrotoluene 2-NT 88-72-2,3-Nitrotoluene 3-NT 99-08-1,4-Nitrotoluene 4-NT 99-99-0,a Chemical Abstracts Service Registry number,1.2 Method 8330 provides a salting-out extraction procedure for low,concentration (parts per trillion, or nanograms per liter) of explosives residues,in surface or ground water. Direct injection of diluted and filtered water,samples can be used for water samples of higher concentration (See Table 1).,1.3 All of these compounds are either used in the manufacture of,explosives or are the degradation products of compounds used for that purpose.,When making stock solutions for calibration, treat each explosive compound with,caution. See NOTE in Sec. 5.3.1 and Sec. 11 on Safety.,1.4 The estimated quantitation limits (EQLs) of target analytes,determined by Method 8330 in water and soil are presented in Table 1.,1.5 This method is restricted to use by or under the supervision of,analysts experienced in the use of HPLC, skilled in the interpretation of,CD-ROM 8330 - 2 Revision 0,September 1994,chromatograms, and experienced in handling explosive materials. (See Sec. 11.0,on SAFETY.) Each analyst must demonstrate the ability to generate acceptable,results with this method.,2.0 SUMMARY OF METHOD,2.1 Method 8330 provides high performance liquid chromatographic (HPLC),conditions for the detection of ppb levels of certain explosives residues in,water, soil and sediment matrix. Prior to use of this method, appropriate sample,preparation techniques must be used.,2.2 Low-Level Salting-out Method With No Evaporation: Aqueous samples,of low concentration are extracted by a salting-out extraction procedure with,acetonitrile and sodium chloride. The small volume of acetonitrile that remains,undissolved above the salt water is drawn off and transferred to a smaller,volumetric flask. It is back-extracted by vigorous stirring with a specific,volume of salt water. After equilibration, the phases are allowed to separate,and the small volume of acetonitrile residing in the narrow neck of the,volumetric flask is removed using a Pasteur pipet. The concentrated extract is,diluted 1:1 with reagent grade water. An aliquot is separated on a C-18 reverse,phase column, determined at 254 nm, and confirmed on a CN reverse phase column.,2.3 High-level Direct Injection Method: Aqueous samples of higher,concentration can be diluted 1/1 (v/v) with methanol or acetonitrile, filtered,separated on a C-18 reverse phase column, determine at 254 nm, and confirmed on,a CN reverse phase column. If HMX is an important target analyte, methanol is,preferred.,2.4 Soil and sediment samples are extracted using acetonitrile in an,ultrasonic bath, filtered and chromatographed as in Sec. 2.3.,3.0 INTERFERENCES,3.1 Solvents, reagents, glassware and other sample processing hardware,may yield discrete artifacts and/or elevated baselines, causing misinterpretation,of the chromatograms. All of these materials must be demonstrated to be free,from interferences.,3.2 2,4-DNT and 2,6-DNT elute at similar retention times (retention time,difference of 0.2 minutes). A large concentration of one isomer may mask the,response of the other isomer. If it is not apparent that both isomers are,present (or are not detected), an isomeric mixture should be reported.,3.3 Tetryl decomposes rapidly in methanol/water solutions, as well as,with heat. All aqueous samples expected to contain tetryl should be diluted with,acetonitrile prior to filtration and acidified to pH <3. All samples expected,to contain tetryl should not be exposed to temperatures above room temperature.,3.4 Degradation products of tetryl appear as a shoulder on the 2,4,6-TNT,peak. Peak heights rather than peak areas should be used when tetryl is present,in con……
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