Catalyst regeneration and activity enhancement of Au/TiO2 by atmospheric pressure nonthermal plasma

Abstract

In this work, a nonthermal plasma was applied to the TiO₂-supported gold nanoparticle catalysts (Au/TiO₂) for the catalyst regeneration and the enhancement of catalytic activity for CO oxidation. Exposure to the 100 ppm toluene or C₃H₆ resulted in rapid deactivation of the Au/TiO₂ catalyst. Oxygen plasma and O₃ injection were found to be effective in the regeneration of the deactivated Au/TiO₂ catalysts. The adsorbed toluene or C₃H₆ preferentially decomposed to CO₂ regardless of the regeneration method. Direct application of nonthermal plasma greatly enhanced the CO oxidation not only over the completely deactivated Au/TiO₂ catalysts, but also over the Au/TiO₂ catalysts prepared by the impregnation method, which showed no catalytic activity without plasma.