Determination of Rocket Kerosene in Soil by Static Headspace Analysis Coupled with Gas Chromatography-Mass Spectrometry

A method has been developed for determining rocket kerosene (RG-1 and T-1) in soil by static headspace analysis with subsequent gas chromatography-mass spectrometry analysis. It has been shown that the headspace analysis of a solid sample is the preferred approach to sample pretreatment compared with the ultrasonic extraction by methanol and the analysis of the equilibrium headspace collected above the extract. The effects of the temperature, the incubation time of the sample, and the moisture of the sample on the extraction and the sensitivity of the headspace determination of rocket kerosenes in soils of different nature have been considered. It has been found that 1 cm(3) of the headspace collected above the sample at the temperature of 90 degrees C for 20 min should be injected into a chromatograph (splitless injection mode) to determine the mass concentration of kerosenes in soil in the range of 50-500 mg kg(-1). To determine the concentration in the range of 500-20000 mg kg(-1), 0.1 cm(3) of the headspace collected under similar conditions should be injected into a chromatograph (split mode, 1 : 10). The repeatability of the measurements for the studied concentration ranges is 12-6% and the intermediate precision is 14.3-7.4%. The gas chromatography analysis takes 41 min.