Determination of alkylphenols and linear alkylbenzene sulfonates in sediments applying accelerated solvent extraction (ASE)

A time and solvent saving method (accelerated solvent extraction, ASE) for the extraction of anionic surfactants as linear alkylbenzene sulfonates (LAS) and alkylphenols from sediments is presented. The analytes are extracted by methanol at 100° C and 150 atm within 10 min of static and 5 min of dynamic extraction. The presence of methanol and a maximum pressure of 150 atm are essential for the complete extraction of anionic surfactants, whereas the extraction of alkylphenols is independent of both parameters. The extraction of alkylphenolethoxylates yielded only unsatisfactor results. It was demonstrated that the ASE extraction is selective for LAS surfactants, while matrix substances, which are extracted by the methanol extraction and interfere with the target analytes during the HPLC-run, remain in the sample. Thus, a further clean-up procedure of the ASE extract is not necessary.