Partition Isotherms of Chlorobenzenes in a Sediment-Water System

Abstract

Partition experiments for a series of chlorobenzenes, 1,4-dichlorobenzene (1,4-DCB), 1,3,5-trichlorobenzene (1,3,5-TCB), 1,2,4,5-tetrachlorobenzene (1,2,4,5-TeCB), pentachlorobenzene (QCB), and hexochlorobenzene (HCB), in a sediment-water system were carried out and the sediment-water partition isotherms for the chlorobenzenes were determined. The partition isotherms were well described by the linear and the Langmuir models. However, experimental data indicated that the partition isotherms exhibited non-linear trends at high concentrations. The maximum concentrations that can be adsorbed from the Langmuir model decreased with KOW values of the chlorobenzenes. QSAR analysis showed that strong relationships exist between the partition parameters (partition coefficients and maximum concentration that can be adsorbed) and physicochemical properties (molar volume, solubility in water, and KOW values).