A green, environmental friendly and sensitive method for determination of volatile organohalogen compounds was described in this paper. The method is based on a homemade sol–gel single-walled carbon nanotube/silica composite coated solid-phase microextraction to develop for sampling and analysis of Carbon tetrachloride, Benzotrichloride, Chloromethyl methyl ether and Trichloroethylene in air. Application of this method was investigated under different laboratory conditions. Predetermined concentrations of each analytes were prepared in a home-made standard chamber and the influences of experimental parameters such as temperature, humidity, extraction time, storage time, desorption temperature, desorption time and the sorbent performance were investigated. Under optimal conditions, the use of single-walled carbon nanotube/silica composite fiber showed good performance, high sensitive and fast sampling of volatile organohalogen compounds from air. For linearity test the regression correlation coefficient was more than 98% for analyte of interest and linear dynamic range for the proposed fiber and the applied Gas Chromatography-Flame Ionization Detector technique was from 1 to 100 ngmL−1. Method detection limits ranged between 0.09 to 0.2 ngmL−1 and method quantification limits were between 0.25 and 0.7 ngmL−1. Single-walled carbon nanotube/silica composite fiber was highly reproducible, relative standard deviations were between 4.3 to 11.7 percent.

Single walled carbon nanotubes (SWCNTs)/silica composite coating for solid phase microextrac tion synthesized by sol−gel technology was developed for air sampling and determination of perchloroethylene, benzotrichloride, chloromethyl methyl ether and trichloroethylene. Application of this method was investigated under different laboratory conditions. Predetermined concentrations of each analyte were prepared in a home made standard chamber and the influence of temperature, humidity, extraction time, storage time, desorption temperature and desorption time was investigated. Under optimal conditions, the use of SWCNTs/silica com posite fiber showed high sensitivity and fast sampling of halogenated volatile organic compounds from air. For linearity test, the regression correlation coefficient was more than 98% for analytes of interest and linear dynamic range for the proposed fiber and the applied gas chromatography−flame ionization detector (GC−FID) technique was from 1 to 100 ng/mL Method detection limits ranged from 0.11 to 0.2 ng/mL and method quan tification limits were between 0.34 and 0.7 ng/mL. SWCNTs/silica composite fiber was highly reproducible; rel ative standard deviations were between 5.6 and 11.7%. The developed method was applied to determine per chloroethylene concentration of real air samples of a dry cleaning shop and the results compared with the data obtained with commercially available carboxen/polydimethylsiloxane (CAR/PDMS).

No abstract