Analytical Procedure for the Determination of Chlorobenzenes in Sediments

Abstract

This study presents the procedure for the determination of chlorobenzenes in sediment. It consists of solvent extraction (shaking overnight), extract clean-up with the use of a homemade glass column packed with activated silica gel and freshly activated copper, and slow solvent evaporation to a volume of 0.3 mL. Two-microliter extract portions are analyzed by means of gas chromatography with an Rtx-624 capillary column (60 m x 0.32 mm, d(f) = 1.8 microm) coupled with mass spectrometry (in selected ion-monitoring mode). Deuterated 1,2-dibromobenzene is used as the recovery standard. The recovery of this method for all chlorobenzenes is high (ranging from 78% to 107%) with the exception of monochlorobenzene, which is 58%. The method is also characterized by good precision, which is commonly accepted in the analysis of trace organic pollution.