Oxidation of sulfur ions in oilfield wastewater by montmorillonite loaded Mn-catalyzed hydrogen peroxide oxidation

In this paper, the sulfur ions in oilfield wastewater were treated by oxidation to harmless elemental sulfur or high valence sulfur-containing organics using hydrogen peroxide catalyzed by montmorillonite-loaded manganese oxides (B@Mn) as a catalyst.The effects of pH, hydrogen peroxide dosage, reaction time, and temperature on sulfide removal were studied separately.The results show that the best reaction conditions were achieved when the simulated wastewater concentration was 25.6 mg/L (pH = 8) and the molar ratio of hydrogen peroxide to sodium sulfide was 5.1:1 (T = 30°C).Under the optimal conditions, the sulfide ion concentration of the B@Mn-4 catalyst was reduced to 0.0225 mg/L.Further, the morphology and pore structures of catalyst were studied in detail using various characterization methods including scanning electron microscopy, UV-vis spectrophotometry, thermogravimetric, and N 2 adsorption-desorption analysis.