Selective CO oxidation over promoted Au/γ-Al2O3 catalysts in the presence of CO2 and H2O in the feed

In this work, the effect of promoter type (Mg, Mn, Ce, Co, Fe and Ni) on selective CO oxidation performance of Au/γ-Al2O3 was studied with the realistic feed stream containing CO2 and H2O. The effects of Au loading, promoter loading, reaction temperature and the feed composition were also investigated. It was found that MgO was the best promoter in the presence of CO2 and H2O, and 1.25 wt.% Mg was sufficient for promotion. The CO conversion decreased with the addition of CO2 while the presence of H2O had some positive effects.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights►Decrease of temperature (150–50 °C) increased conversion in absence of H2O & CO2 ►Mg and Mn promoted Au better than Fe, Ni, Co and Ce in presence of H2O & CO2 ►Activity increased with increasing Mg first, and then decreased at higher Mg % ►Effect of CO2 was negative while H2O positively affected CO conversion