SORPTION OF 1,2,3,4-TETRACHLOROBENZENE TO SEDIMENTS - THE APPLICATION OF A SIMPLE 3 PHASE MODEL

The partition coefficients for 1,2,3,4-tetrachlorobenzene to three sediments were measured at different sediment to water ratio's with a batch equilibration method. The measured concentration dependency was described by a simple three phase model. A characterisation of the non separable fraction showed that the composition of this fraction varied significantly with sediment concentration. Despite of this variation, the three phase model used one organic carbon normalised sorption constant for the particulate organic matter (logKoc= 4.26) and one for the organic matter in the non separable fraction (logKoc= 3.90). Apart from incomplete phase separation, a major part of the concentration dependency originated from the adsorption of test compound to the container walls, so a correction for this phenomenon was included in the model.