Metal oxide-incorporated polyphenylene sulfide for enhanced catalytic oxidation of sodium sulfide

In this study, a novel heterogeneous catalyst was developed for the deep oxidation of sulfides to sulfates. Heterogeneous catalysts were synthesized with metal oxides as active substances (MnO2, CuO, TiO, Fe2O3, NiO, CdO, Mn2O3, Cr2O3, PbO, MnO, Cu2O) on polyphenylene sulfide (PPS) as the support (matrix). The activity of each heterogeneous catalyst in liquid-sulfide oxidation under severe conditions (high temperature, high pressure, and high sulfide concentration) was investigated. The research results show that the catalyst containing MnO2 incorporated onto PPS is considered the most effective for liquid-sulfide oxidation. Factors influencing the catalytic activity in inorganic sulfide oxidation were evaluated to provide the optimal conditions for this process. To confirm the effectiveness of the heterogeneous catalyst in treating wastewater containing inorganic sulfide, the toxicity was evaluated before and after oxidation. The biological testing method was carried out with the test subject Paramecium caudatum, and the research results indicated that toxicity was significantly reduced after oxidation with a catalyst. This study contributes to solving the problem of sulfide removal in wastewater, especially at high concentrations.