ASE-GC Determination of n-Alkanes in Sediments

The sample was extracted statically by accelerated solvent extraction at 120 ℃ for 10 min with a mixture of acetone and dichloromethane (1+1). The extract was purified on a column packed with silica gel and neutral alumina, and a mixture of hexane-acetone (9+1) was used as eluent. The eluate was separated by GC, and external standard method was used for quantification. Linearity ranges for the compounds were kept between definite mass concentrations. Values of detection limits (3S/N) found were in the range of 0.02-0.17 mg·L^-1. Test for recovery was made by standard addition method at 3 concentration levels, giving results in the range of 72.1%-91.7%, with RSDs (n=6) ranged from 1.8% to 16%.