The catalytic aerial oxidation of As(III) in alkaline solution by Mn-loaded diatomite

The oxidization of As(III) to As(V) is necessary for both the detoxification of arsenic and the removal of arsenic by solidification. In order to achieve high efficiency and low cost As(III) oxidation, a novel process of catalytic aerial oxidation of As(III) is proposed, using air as oxidant and Mn-loaded diatomite as a catalyst. Through systematic characterization of the reaction products, the catalytic oxidation reaction law of Mn-loaded diatomite for As(III) was found out, and its reaction mechanism was revealed. Results show that Mn-loaded diatomite achieved a good catalytic effect for aerial oxidation of As(III) and maintained high performance over multiple cycles of reuse, which was directly related to the structure of diatomite and the behavior of manganese. Under the conditions of a catalyst concentration of 20 g/L, an air flow rate of 0.3 m