MTBE Removal by Heterogeneous Ozonation

摘要

This paper presents the results of application of heterogeneousrnozonation using granular iron oxide mineral for MTBE removal. As itrnwas presented earlier, this process significantly improves the oxidationrnrate of organic compounds through enhancement of ozone massrntransfer rate and possibly formation of free radicals.rnThe laboratory experiments were conducted by ozonating MTBErnsolutions in the presence and absence of iron oxide mineral at differentrnconcentrations. The reaction rates and the oxidation products werernstudied in order to elucidate the reaction mechanisms.rnSome of the major conclusions of the study include the following:rn? Ozone reaction with MTBE is totally negligible.rn? Large amounts of MTBE can easily be stripped during ozonationrnunder normally encountered conditions.rn? MTBE reacts only with the hydroxyl radical that is generatedrnduring ozone decomposition, which is very slow for practicalrnpurposes.rn? Ozonation in the presence of iron oxide minerals is very effective inrnremoval of MTBE and its reaction products, including tertiary butylrnalcohol, tertiary butyl formate and acetone, although there seems tornbe an optimum dosage.rn? Presence of iron oxide particles enhances the rate of mass transferrnof ozone from the gas phase into the liquid phase significantly.rn? Presence of iron oxide particles reduces the stripping of MTBE tornthe gas phase.