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

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.

This paper describes the application of atmospheric pressure nonthermal plasmas for the oxidation of CO over gold (Au) nanoparticle catalysts. Nonthermal plasma was used for two different purposes of the regeneration of the deactivated Au/TiO2 catalyst and the enhancement of catalytic activity by in situ plasma. Oxygen plasma and O3 injection were found to be effective in the regeneration of the deactivated Au/TiO2 catalysts. In situ plasma greatly enhanced the CO oxidation over both the deactivated catalysts and Au/TiO2 catalyst prepared by an impregnation method.Figure optionsDownload as PowerPoint slide