Photo-oxidation of an endocrine disrupting chemical o-chloroaniline with the assistance of TiO2 and iodate: Reaction parameters and kinetic models

An efficient photo-oxidation system was introduced to decay a typical endocrine disrupting chemical o-chloroaniline (o-CIA) by using UV light with the assistant of TiO2 and IO3 (UV/TiO2/KIO3 system). The o-CIA decay in UV/TiO2/KIO3 system is much superior to sole UV and UV/TiO2. For depth evaluating the system, the effect of TiO2 dosages, KIO3 dosages, and initial pH levels ([TiO2](0), [KIO3](0) and pH(0)) were investigated and optimized. The optimum o-CIA decay was achieved at [KIO3](0) of 66.7 mg/L and pH(o) of 7.09. The kinetics analysis showed that the o-ClA decay followed a two-stage pseudo first-order, and the decay rate constants at both stages (k(1) and k(2)) are significantly influenced by [TiO2]0, [KIO3](0) and pH(o). After data analysis, both 1/k(1) and 1/k(2) were found linearly correlated to [KIND, pHo and 1/[TiO2](o). Mathematic models were therefore derived for predicting o-CIA decay in terms of [TiO2](0), [KIO3](o) and pH(o). Moreover, the proposed models offered efficient approaches to predict the o-CIA decay in UV/TiO2/KIO3 system under various conditions. (C) 2014 Elsevier B.V. All rights reserved.