Kinetics Analysis on the Ozonation of MIB and Geosmin

Abstract The ozonation of 2-methylisoborneol (MIB) and geosmin was investigated in both pure and raw water. In a semi-batch reactor, a series of experiments was performed to determine the effect of pH on the ozonation of MIB and geosmin. The results show that pH has a significant effect on the ozonation of both compounds, which supports the theory that OH radical plays an important role on the destruction of MIB and geosmin. Compared with MIB, geosmin is more readily destroyed by ozonation. The ozonation kinetics follow approximately a first-order equation with respect to MIB and geosmin at the pH of 5, 7 and 9, and their rate orders of CO3 at pH 7 are 0.44 and 0.61, respectively. Ozonation of organic matters in the water decreases the ozone concentration leading to a lower removal of MIB and geosmin; at the same time, the formation of OH radical initiated by the organic matters accelerates the ozonation of MIB and geosmin. The ozonation of MIB and geosmin spiked in raw water, settled water and pure water shows that background organics have no significant effect on the removal of MIB and geosmin; hence, the simplified rate equations acquired in pure water may have potential application in real water. Keywords: OzoneMIBGeosminKineticsOH Radical ACKNOWLEDGMENTS This study was supported by National 863 program of China under 2002AA601120 and National Natural Science Foundation of China under 20577060.