GC Determination of 21 Phenolic Compounds in High Moisture-Content Soil with Soxhlet Extraction

After mixing with anhydrous sodium sulfate evenly, the sample of high moisture-content soil was extracted (Soxhlet) with the mixture of dichlormethane and hexane (2+1) as extractant. The extract was purified by sodium hydroxide solution. After acidification, the above solution was extracted with the mixture of dichlormethane and ethyl acetate (4+1), and finally concentrated. GC was applied to the determination of 21 phenolic compounds in the concentrated liquid. The analytes were separated on HP-5 chromatographic column (30 m×0.25 mm, 0.25 μm) and detected by FID. Linear relationships between values of peak area and mass concentration of the 21 phenolic compounds were kept in the same range of 1.0-100.0 mg·L^-1, with detection limits in the range of 0.01-0.07 mg·kg^-1. On the base of blank sample, test for recovery was made by standard addition method; values of recovery found were in the range of 71.4%-95.1%, with RSDs (n=6) of determined values in the range of 1.0%-11%.