Advanced Oxidation Processes For The Degradation Of Toluenediamine Wastewater

In the present study, the oxidation of toluenediamine (TDA) by Advanced Oxidation Process (AOPs) has been investigated which including traditional Fenton's process, adsorption, and heterogeneous Fenton process and photocatalytic oxidation.Firstly, the oxidation of TDA by continuously pumping two solutions of ferrous sulfate (FeSO4) and hydrogen peroxide (H2O2) has been investigated. Experiments were conducted to examine the effects of pH, the amounts of FeSO4, H2O2, and temperature on the TDA removal. The mechanism of TDA degradation was proposed and oxidation kinetics was also set up. The apparent activation energy of reaction and the intrinsic reaction rate constant were calculated.Secondly, the adsorption behavior of toluenediamine on activated carbon in batch and fixed bed systems was investigated. The kinetics constant of adsorption and the thermodynamic parameters for the process of adsorption have been estimated.We investigated the influence of activated carbon modified by HNO3, H2O2, NaOH, and NH3H2O on the adsorption of TDA, respectively. The kinetics of adsorption on modified AC was investigated. With the results of the Boehm Method which applied in estimating the content of surface functional groups and the results of BET analysis, the mechanism of adsorption of TDA on modified AC was proposed.Then heterogeneous Fenton method was exploited for treating TDA wastewater in a semi-continuous reactor with the catalyst self-made. Experiments were conducted to examine the effects of pH, the amounts of catalyst, H2O2, and temperature on the TDA removal. The mechanism and kinetics of heterogeneous Fenton reaction were proposed.At last, TDA wastewater was treated by photocatalysis oxidation. The effect of different operational conditions was investigated and the kinetics and mechanism of oxidation were proposed. At the same time, the effect of crystal formation of TiO2 on the oxidation process was investigated by experiments.