ABSTRACT
Objective To establish a method for determining VOCs in drinking water by headspace gas chromatography. Methods VOCs in the water were extracted by headspace technology, then analyzed with Rtx-WAX capillary column, in the same time, VOCs was determined with GC by controlling the temperature and the speed of nitrogen. The retention time of the peaks was used for qualitative analysis, external standard method was used for quantitative analysis. Results The linear ranges of dichloromethane, benzene, toluene, 1, 2-dichloroethane, ethylbenzene, p-xylene, m-xylene, o-xylene, isopropylbenzene, chlorobenzene, styrene were 6.2-311.2, 2.0-100.0, 1.6-81.5, 5.7-282.8, 1.9-93.4, 1.7～85.4, 1.7-87.2, 2.1-103.2, 1.5-76.3, 2.2-107.3 and 1.9-96.0 ?g/L respectively. The lowest determination limit were 0.5-5.9 ?g/L, the rate of recovery were 88.8%-109.6% and RSDs were 2.2%-5.9%. Conclusion This method is simple, rapid, sensitive and can efficiently separate and accurately determine 11 kinds of VOCs in drinking water.
ABSTRACT
Objective To establish a method for simultaneous determination of kelthane and pyrethroid pesticide residues in water.Methods Kelthane and pyrethroid pesticide residues in the water were extracted by liquid-liquid,then analyzed with DB-1 capillary column.In the same time,they were determined with GC by controlling the temperature.Retention time of the peaks was used for qualitative analysis,while external standard method was used for quantitative analysis.Results The linear ranges of Kelthane,Bifenthrin,Fenpropanate,Lambda cyhalothrin,Permethrin,Beta cyfluthrin,Alphacypermethrin,Fenvalerate were 0.24-31.1,0.21-27.2,0.20-26.0,0.21-26.5,0.20-25.7,0.21-26.4,0.22-29.0 and 0.22-27.4 ?g/L,r≥0.999 0.The lowest determination limits were 0.20,0.33,0.30,0.13,0.36,0.26,0.33 and 0.30 ?g/L,the rate of recovery was 86.0%-111.7% and RSD was 3.8%-11.8%.Conclusion This method can separate efficiently and determine 8 kinds of pyrethroid pesticide residues in the water and only needs 23 minutes.It's simple,rapid and sensitive.
ABSTRACT
Objective To establish the method of acetaldehyde and acraldehyde in water with headspace gas chromatography. Methods Acetaldehyde and acraldehyde in the water samples were extracted by headspace technology,then analyzed with DB-624 capillary column. In the same time,they were determined with GC by controlling the temperature. Retention time of the peaks was used for qualitative analysis,while external standard method was used for quantitative analysis. Results In 3.0-250 ?g/L, the regression equation for acetaldehyde was y=406.83 x+0.847,r=0.999 9,the lowest detection limit was 1.0 ?g/L. In 6.2-500 ?g/L, the regression equation for acraldehyde was y=207.53 x-0.450,r=0.999 8,the lowest detection limit was 3.3 ?g/L. The rates of recovery were 90.0%-95.5%,and RSDs were 2.1%-3.7%. Conclusion This method is simple,rapid,sensitive and is applicable to the determination of acetaldehyde and acraldehyde in water.
ABSTRACT
Objective To establish a test method of dichloromethane,1,1-dichloroethylene,1,2-dichloroethylene,1,2-dichloroethane in drinking water with headspace gas chromatography.Methods Halogenated alkane hydrocarbon in the water was extracted by headspace technique,then analyzed with DB-624 capillary column.In the same time,determined with GC by controlling the temperature.Retention time of the peaks was used for qualitative analysis,while external standard method was used for quantitative analysis.Results The linear ranges for dichloromethane,1,1-dichloroethylene,1,2-dichloroethylene,trans-1,2-dichloroethylene,1,2-dichloroethane were 0.85-168,0.07-12.1,0.40-77.8,0.53-119 and 1.2-265 ?g/L respectively,the determination limits were 0.83,0.07,0.40,0.53 and 1.10?g/L respectively,r≥0.999 5,the rate of recovery were 102.5%-113.8%,and RSDs were 5.5%-11.8%.Conclusion This method is simple,rapid and sensitive,can efficiently separate and accurately determine 5 kinds of halogenated alkane hydrocarbon in the water and only takes 5.2 minutes.
ABSTRACT
Objective To develop a method of determining benzene hydrocarbon and halogenated alkane hydrocarbon in the air of workplaces with the capillary gas chromatography of carbon disulphide desorption. Methods Benzene hydrocarbon and halogenated alkane hydrocarbon in the air of workplace were collected by active carbon sampling cuvette, then separated by hydrogen flames detector gas chromatography machine after carbon disulphide desorption. Benzene hydrocarbon and halogenated alkane hydrocarbon were determined quantitively by retention time and quantitatively by apex area. Results The linear ranges of benzene, toluene, p-xylene, m-xylene, o-xylene, ethyl benzene, styenl, chlorobenzene, acetone, carbontetrachloride, dichloromethanl, trichloromethane, 1, 2-dichloroethane, naphth alene were 0.019-81.600, 0.018-91.200, 0.018-88.800, 0.018-56.8, 0.011-92.000, 0.012-63.200, 0.018-93.200, 0.449-2298.400, 0.252-1287.000 and 0.076-390.000 mg/m3 respectively. The recovery rates were 88.4%-98.6% and RSD were 1.0%-6.0%. Conclusion This method can separate efficiently and determine accurately benzene hydrocarbon and halogenated alkane hydrocarbon in the air with a good precision. It is suitable for the determination of the toxicants in the air.