Ordered nanoporous carbon as an effective adsorbent in solid-phase microextraction of toluene and chlorinated toluenes in water samples

Ordered nanoporous carbon (cmk-3) has been synthesized and immobilized onto a copper wire,and subsequently applied to headspace solid phase microextraction (hs-spme) of toluene,4-chlorotoluene,2,4-dichlorotoluene and 2,6-dichlorotoluene following gas chromatography–flame ionization detection (gc–fid). the structural order and textural properties of the prepared materials have been characterized by n2 sorption analyses,scanning electron microscopy (sem) and x-ray diffraction (xrd). five experimental parameters such as extraction temperature,extraction time,salt concentration and stirring speed have been evaluated and optimized by means of a taguchi's oa16(45) orthogonal array experimental design. the experimental results indicate that extraction temperature and extraction time are the most significant factors in the analysis procedure. the optimum extraction conditions were as follows: 12 ml sample volume; ambient temperature; 10% (w/v) nacl; 35 min extraction time and stirring rate of 600 rpm. under the optimized conditions for all analyzed compounds,the linearity was from 2.5 to 400 μg l−1,and limit of detections (lods) were between 0.02 and 0.08 μg l−1. the relative standard deviation values were ⩽5.25% and recovery values were between 85.60% and 104.12%. this method has been successfully used for preconcentration and analysis of above mentioned compounds in different real water samples. © 2012