Determination of lower halogenated hydrocarbons by the water-xylene extraction method

Abstract

A modified liquid extraction method for determining trace amounts of lower halogenated hydrocarbons in drinking water has been studied. A 45 ml sample solution containing not less than 5 μg litre⁻¹ of CHCl₃, CHCl:CCl₂, CHBrCl₂, CHClBr₂, CHBr₃ and CCl₂:CCl₂ and 0·4 μg litre⁻¹ of CCl₄ was extracted with 5 ml of xylene. The equilibrium concentrations of lower halogenated hydrocarbons in the xylene phase were determined by a gas chromatograph equipped with an electron capture detector and using a column which consists of tricresyl-phosphate (90 cm), squalane (170 cm) and silicone DC 200 (40 cm).

By means of this method, μg litre⁻¹ levels of lower halogenated hydrocarbons in drinking water were determined successfully.