Hydrothermal preparation of NiO/La–NaTaO3 composite photocatalyst for degradation of ammonium dibutyl dithiophosphate wastewater

The discharge of a large amount of flotation reagents wastewater can cause significant environmental pollution. In this study, NiO/La–NaTaO3 nano-photocatalyst was prepared and applied to degrade synthetic flotation reagent ammonium dibutyl dithiophosphate wastewater. Various characterization results confirmed the successful synthesis of NiO/La–NaTaO3, and UV–vis DRS analysis revealed a band gap of 3.96 eV for 4 wt% NiO/2.5% La–NaTaO3. Under UV light, the degradation rate of 20 mg 4 wt% NiO/2.5% La–NaTaO3 photocatalyst reached its optimum within 4.5 h at pH=3, exhibiting a 1.45 times improvement compared to pure NaTaO3. Radical trapping experiments and EPR results showed that ·OH and·O2− showed major contribution to the degradation. Furthermore, photocatalytic mechanisms and toxicity evolution were investigated, demonstrating the potential application of photocatalytic methods for treating flotation reagent wastewater.