Abstract
Soil and groundwater pollution from trichloroethylene has recently been noted. In the present work kinetics for decomposition of trichloroethylene using Fenton's reaction are discussed. This study found that the reaction was first-order for concentration of trichloroethylene, 0.8-order for concentration of iron ion and half-order for concentrations of hydrogen peroxide. The reaction rate constant was given as 0.205 (l · mol-1) 1.3 · s-1. Additional experiments were carried out in the presence of humic acid (HA), the most abundant organic compound in soil. The reaction with HA was first-order for concentrations of trichloroethylene and Fe (II) iron, and 0.8-order for concentration of hydrogen peroxide, and the reaction rate constant was 0.865 (l · mol-1) 1.8 · s-1. In spite of small difference in reaction order, these reaction rates are almost the same with and without humic acid under the present conditions.
At the initial stage of these reactions, concentrations of trichloroethylene were found to be reduced rapidly. The correlation to calculate the reduction amounts is proposed. Finally, equations to predict the variation of trichloroethylene concentration using Fenton's reaction are suggested.
