Evaluation of in situ air sparging for MTBE removal from a gasoline source

MTBE removal from a gasoline source by volatilization was studied and the overall impact of the in-situ air sparging system on downgradient concentrations after treatment was evaluated. MTBE had the highest concentration in the offgas. However, the magnitudes of mass removal of the four compounds were in the same order as the constituents' concentrations in the original gasoline. MTBE removal was significantly less than that of isooctane with respect to the initial mass of each that was spilled. This reflects both the high mobility of the MTBE, and the difficulty of stripping this very soluble compound from the aqueous phase. This is significant because high concentrations of MTBE in the offgas and corresponding high mass removal result in removing relatively low percentages of the contaminant from the source zone.