Direct determination of hydrophobic organic compounds in aqueous solution in the presence of dissolved organic carbon by high-performance liquid chromatography

A simple and quick method using high performance liquid chromatography is presented to determine hydrophobic organic compounds in aqueous solutions containing dissolved organic carbon. The analytical procedure does not require an extraction or purification step unlike conventional analytical approaches. It was used to measure the water solubility of dibenzofuran (4.55 mg l−1), acenaphthene (3.30 mg l−1), fluoranthene (0.23 mg l−1) and 4-chlorobiphenyl (1.47 mg l−1). The results were compared with those obtained by gas chromatographic quantification. The method was applied successfully to the direct determination of the water solubility of these compounds in the presence of DOC. In a solution of Aldrich humic acid, the water solubility of dibenzofuran, acenaphthene and 4-chlorobiphenyl increased linearly with increasing DOC concentration. The water extractable organic matter from peat led to a smaller solubility of dibenzofuran comparing to the Aldrich humic acid in the same concentration range of DOC.