Synthesis of Supported Ruthenium Catalyst for Phenol Degradation in the Presence of Peroxymonosulfate

Industrial synthesis processes produce high concentration of hazardous organic pollutants into water body, which must be removed before being discharged. Advanced oxidation processes (AOPs) using heterogeneous catalysts has been widely utilized for wastewater treatment. Here, RuO2-based catalyst was synthesized by a general impregnation method and used to oxidize phenol by peroxymonosulfate (PMS) as an oxidant in aqueous solution. The properties of this supported catalyst were characterized by SEM (scanning electron microscopy), XRD (powder X-ray diffraction), and nitrogen adsorption-desorption. The mesoporous Al2O3 support had large surface area and high thermal stability. It is found that ruthenium oxide-based catalyst is highly effective to activate PMS to related sulfate radicals. The effects of catalyst loading, phenol concentration, PMS concentration, reaction temperature, and reusability of the as-prepared catalyst on phenol degradation have been investigated. Overall, our findings demonstrate that in RuO2/Al2O3 mesoporous catalyst, Oxone (PMS) is effectively activated, and 100% phenol degradation occurs in 60 min. To regenerate the deactivated catalyst and improve its catalytic properties, three different methods involving annealing in air, washing with water, and applying ultrasonics were used. The catalyst was recovered thoroughly by heating treatment.