Extraction of benzene, toluene, ethyl benzene, xylene and cumene from soil using methanol at elevated temperature and pressure

Abstract

A system for solvent extraction at elevated temperature and pressure has been constructed from parts of HPLC and GC instruments. The apparatus has been used successfully to remove benzene, toluene, ethyl benzene, p-xylene and cumene from vapour-fortified clay soil. Quantitative recoveries (100 ± 10%) were obtained for all analytes, provided the collection vial was cooled to around –3 °C in an ice–salt mixture. When the performance was compared with that of a commercial, accelerated solvent extraction system, similar levels of ethyl benzene, p-xylene and cumene were extracted. However, the recoveries and, in particular, the reproducibility were significantly better for benzene and toluene with the system developed.

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