Enhanced Water Resistance and Catalytic Performance of Ru/TiO2 by Regulating Brønsted Acid and Oxygen Vacancy for the Oxidative Removal of 1,2-Dichloroethane and Toluene.

Abstract

The compositions of volatile organic compounds (VOCs) under actual industrial conditions are often complex; especially, the interaction of intermediate products easily leads to more toxic emissions that are harmful to the atmospheric environment and human health. Herein, we report a comparative investigation on 1,2-dichloroethane (1,2-DCE) and (1,2-DCE + toluene) oxidation over the Ru/TiO2, phosphotungstic acid (HPW)-modified Ru/TiO2, and oxygen vacancy-rich Ru/TiOx catalysts. The doping of HPW successfully introduced the 1,2-DCE adsorption sites to promote its oxidation and exhibited outstanding water resistance. For the mixed VOCs, Ru/HPW-TiO2 promoted the preferential and superfluous adsorption of toluene and resulted in the inhibition of 1,2-DCE degradation. Therefore, HPW modification is a successful strategy in catalytic 1,2-DCE oxidation, but Brønsted acid sites tend to adsorb toluene in the mixed VOC oxidation. The Ru/TiOx catalyst exhibited excellent activity and stability in the oxidation of mixed VOCs and could inhibit the generation of byproducts and Cl2 compared with the Ru/HPW-TiO2 catalyst. Compared with the Brønsted acid modification, the oxygen vacancy-rich catalysts are significantly suitable for the oxidation of multicomponent VOCs.