Enhancement of Mineralization Ability and Water Resistance of Vanadium-Based Catalysts for Catalytic Oxidation of Chlorobenzene by Platinum Loading.

ABSTRACT

The design of a catalyst with multifunctional sites is one of the effective methods for low-temperature catalytic oxidation of chlorinated volatile organic compounds (CVOCs). The loss of redox sites and competitive adsorption of H2O prevalent in the treatment of industrial exhaust gases are the main reasons for the weak mineralization ability and poor water vapor resistance of V-based catalysts. In this work, platinum (Pt) is selected to combine with the V/CeO2 catalyst, which provides more redox sites and H2O dissociative activation sites and further enhances its catalytic performance. The results show that PtV/CeO2 achieves 90% of the CO2 yield at 318 °C and maintains excellent catalytic activity rather than continuous deactivation within 15 h after water vapor injection. The formation of Pt-O-V bonds enhances the redox ability and promotes deep oxidation of polychlorinated intermediates, accounting for the significantly improved mineralization ability of PtV/CeO2. The dissociative activation effect of Pt on H2O molecules strengthens the migration and activation of V-adsorbed H2O, precluding V-poisoning and notably improving water resistance. This study lays a solid foundation for the efficient degradation of chlorobenzene under humid conditions.