Catalytic technology for water treatment by micro arc oxidation on Ti–Al alloy

The feasibility of the formation of a liquid plasma catalysis system through micro arc oxidation (MAO) under AC power with titanium–aluminum alloy electrodes was investigated. In the decolorization of organic dyeing wastewater simulated with Rhodamine B, Ti–Al alloy electrodes were superior over Ti electrodes and Al electrodes. The optimal molar percentage of Ti in alloy electrodes was 70% and the optimal decolorization rate was up to 88.9% if the additive suitable for Al was added into the solution to be treated. The decolorization rates were the same in the case of the alloy–alloy electrodes and alloy–Al electrodes. The proportion of the effects of plasma, TiO2 catalyzer during MAO and H2O2 after MAO in decolorization has been obtained. With the catalysis of TiO2 formed on the electrodes, the reaction rate was improved by a maximum of 95% and the decolorization rate was improved by a maximum of 71.6%. Based on the spectral analysis, the plasma catalysis mechanism has been studied.