Trace determination of phthalate esters in river water by solvent sublation followed by high-performance liquid chromatography-ultraviolet detection

A novel method for separating and enriching trace phthalate esters (PAEs) in river water by solvent sublation and their determination by high-performance liquid chromatography (HPLC) has been developed. The optimal conditions of the solvent sublation were obtained, that is n-hexane as the sublation solvent, pH 7 of the solution, a nitrogen flow rate of 70 mL min-1 and sublation time of 70 min. The floated product under the optimal conditions was determined by HPLC. In the process of HPLC analysis, an Eclipse XDB-C18 chromatographic column was used, and mobile phase consisted of acetonitrile and water using gradient elution, and the flow rate was 1.00 mL min-1. The proposed method was applied to determine eight PAEs in the river water from Fangshan District, Beijing; the recoveries ranged from 76.9 to 120.4%, RSD values from 2.63 to 9.71%, and limit of detection values ranged from 0.001 (for diethyl phthalate and butyl benzyl phthalate) to 0.225 g L-1 (for dimethyl phthalate and dicyclohexyl phthalate).