Determination of Semi-Volatile Organic Compounds in Petroleum Hydrocarbon Contaminated Soil by Solid Phase Extraction-Gas Chromatography-Mass Spectrometry

The sample of petroleum hydrocarbon contaminated soil was extracted by rapid extractor, and purified with activated Silica gel solid-phase extraction column. n-Hexane was used as rinse solvent, and the initial 1.0 mL of rinse solution was discarded, then the analytes were eluted from the column with acetone-n-hexane mixed solvent (the vlume ratio of 1:19). The eluate was concentrated and dried to less than 1.0 mL by nitrogen blowing, and the residue was added with internal standard and made up its volume to 1.0 mL, and the solution was filtered. Semi-volatile organic compounds (SVOC) in filtrate were separated by GC and determined by MS with EI, full scan mode and selective ion monitoring mode. The effect of the different solid phase extraction columns, the amount of n-hexane, and the type of eluent on purification of sample were compared. Under the optimized test conditions, linearity ranges of SVOC were found in the same range of 1-20 mg·L^-1, with detection limits in the range of 0.06-0.30 mg·kg^-1. Tests for recovery were made by standard addition method at the three concentration levels, higer values of recovery were found at the low standard addition level in the range of 35.8%-145%. RSDs (n=6) of measured values were ranged from 0.60% to 15%.