Gold stabilized on reducible oxide (CeO2 and FeOx) and irreducible oxide (γ‐Al2O3, SiO2, and HZSM‐5) were prepared by deposition precipitation method and tested for catalytic oxidation of formaldehyde (HCHO) ...Gold stabilized on reducible oxide (CeO2 and FeOx) and irreducible oxide (γ‐Al2O3, SiO2, and HZSM‐5) were prepared by deposition precipitation method and tested for catalytic oxidation of formaldehyde (HCHO) at room temperature under high GHSV of 600000 ml/(g·s). Au/γ‐Al2O3 cata‐lyst showed distinctive catalytic performance, presenting the highest initial HCHO conversion and stability. Correlating the reaction rate with Au particle size, there is a linear relationship, suggesting that the smaller Au particle size with higher dispersion possesses high reactivity for HCHO oxida‐tion. All the catalysts deactivated at high GHSV (600000 ml/(g·s)), but in a quite different rate. Re‐ducible oxide (CeO2 and FeOx) could stabilize gold through O linkage and therefore exhibits a better stability for HCHO oxidation reaction. However, the aggregation of gold particles occurred over Au/SiO2 and Au/HZSM‐5 catalysts, which result in the fast deactivation. Therefore, our results sug‐gest that the reducibility of the supports for Au catalysis has no direct influence on the activity, but affects the catalytic stability.展开更多
基金supported by the National Natural Science Foundation of China(21373037,21577013)China Postdoctoral Science Foundation(2014M560201)the Fundamental Research Funds for the Central Universities(DUT15TD49,DUT16ZD224)~~
文摘Gold stabilized on reducible oxide (CeO2 and FeOx) and irreducible oxide (γ‐Al2O3, SiO2, and HZSM‐5) were prepared by deposition precipitation method and tested for catalytic oxidation of formaldehyde (HCHO) at room temperature under high GHSV of 600000 ml/(g·s). Au/γ‐Al2O3 cata‐lyst showed distinctive catalytic performance, presenting the highest initial HCHO conversion and stability. Correlating the reaction rate with Au particle size, there is a linear relationship, suggesting that the smaller Au particle size with higher dispersion possesses high reactivity for HCHO oxida‐tion. All the catalysts deactivated at high GHSV (600000 ml/(g·s)), but in a quite different rate. Re‐ducible oxide (CeO2 and FeOx) could stabilize gold through O linkage and therefore exhibits a better stability for HCHO oxidation reaction. However, the aggregation of gold particles occurred over Au/SiO2 and Au/HZSM‐5 catalysts, which result in the fast deactivation. Therefore, our results sug‐gest that the reducibility of the supports for Au catalysis has no direct influence on the activity, but affects the catalytic stability.