EXTRACTION OF LIGHT-HYDROCARBONS FROM SOIL

The recovery of light hydrocarbon constituents from three soils using three kinds of extraction methods, conducted in duplicates, was evalua ted. Higher molecular weight compounds were recovered at greater than 80% whereas the recoveries of benzene, toluene, ethylbenzene, and xyle ne were generally less than 50%. Using the most efficient extraction p rocedure, the average recovery of light hydrocarbon from a soil. was 7 8%. Increased soil moisture content decreased the extent of recovery. Methanol and 2-propanol showed similar extracting potential for light hydrocarbon from soil. The rate of hydrocarbon removal was faster when methanol was used as a solvent, but its efficiency was similar to 2-p ropanol. The batch and column extraction methods gave very similar res ults for both solvents. However, column extraction offered an advantag e over the soxhlet and batch procedures by reaching equilibrium faster .