2.2 Extraction process

Contaminated soil (1g) was mixed with Hydromatrix concentrate (Varian,
UK) at a ratio of 1:1 w/w. The mix was then ground vigorously to such an
extent that it appeared dry and powdery. The sample was then added to 22
ml stainless steel extraction vial (Dionex, UK) partitioned with
disposable cellulose filters (Dionex, 52 UK) and acid washed sand (VWR,
UK). Accelerated solvent extractor (ASE) 200 (Dionex, UK) was utilised
to perform the extraction process by using Dionex method 324. To
facilitate the extraction process, the ASE cell is left in an ASE
carousel. Whilst extraction takes place, hexane/acetone, 1:1 (Fisher
Scientific, UK) was introduced into the extraction cell up to 50 ml.
Upon extraction, the extract was flushed out of the cell into a
collection vial with the help of nitrogen, to be analysed. GC-MS was
utilised to perform the analysis on the extract. Then, 1.5 ml of the
specimen solution was pipetted into the GC auto sampler vial
(Technopath, UK) and capped by crimp caps.