Abstract

Volatile organic compounds (VOCs) have been recognized as major contributor to air pollution. The catalytic oxidationis is one of the most important processes for VOCs destruction due to the possibility getting high efficiency at low temperature. In this study, monometallic Pt, Ir and bimetallic Pt-Ir were supported to TiO2. In order to distribute metals uniformly, H2O-H2 treatment method was used. Xylene, toluene and MEK were used as reactants. The monometallic or bimetallic catalysts were prepared by the excess wetness impregnation method and characterized by XRD, XPS, and TEM analysis.Pt catalyst showed higher conversion than Ir catalyst and Pt-Ir bimetallic catalyst showed the highest conversion. The catalysts prepared by H2O-H2 treatment had better VOC's conversion than that of nothing treatment. In the VOCs oxidation, Pt-Ir bimetallic catalysts had multipoint active sites, so it improved the range of Pt metal state. Therefore, bimetallic catalysts showed higher conversion of VOCs than monometallic ones. H2O-H2 treatment effected an uniform distribution of Pt particles. In VOCs oxidation was found to follow first order reaetion kinetics. The activation energy of H2O-H2 treatment catalysts was lower than that of untreated ones. In this study, the a small amount of Ir was used with Pt to promote the oxidation conversion of VOCs.