Rapid Determination of 37 Volatile Organic Compounds in the Same Sequence of Groundwater and Soil by GC-MS with Purge and Trap Sampling

A method was established for the determination of 37 volatile organic compounds (VOCs) in the same sequence of groundwater and soil samples by GC-MS with purge and trap sampling. The groundwater and soil samples were collected and sealed in 40 mL brown purge bottles. An automatic solid-liquid integrated purge and trap device was adopted. The sample was purged for 11 min at 20 ℃, desorbed for 1.7 min at 250 ℃, and baked for 8 min at 280 ℃. GC-MS was used for analyzing the separated VOCs with internal standard method for quantification. The results showed that RSDs (n=8) of RRF of the targets were less than 11%, and correlation coefficient of the calibration curves were more than 0.998 0. The recovery tests were made on the groundwater and soil samples by standard addition method at 3 concentration levels, giving recovery in the ranges of 75.5%-112% and 82.0%-115%, and RSDs (n=7) of the determined values were found in the ranges of 0.85%-11% and 0.81%-7.9% respectively.