Ionic Liquid-Based Headspace Liquid-Phase Micro-Extraction for the Determination of Dichlorobenzene Isomers in Soils

Headspace liquid-phase microextraction using ionic liquids as extracting solvents, followed by gas chromatographic detection was developed to determine o-dichlorobenzene, m-dichlorobenzene and p-dichlorobenzene in soil samples. The main parameters influencing the extraction of dichlorobenzene isomers were studied using the orthogonal experimental design forming L-9 (3(4)) was chosen. The results showed that the most important factors were enrichment time and pH of solution. Under the optimal conditions, limits of detections (LODs) for dichlorobenzene isomers were in the range of 0.001-0.002 mu g g(-1). The repeatability of the proposed method, expressed as RSD (n = 5), varied between 4.4 and 14.6%.