Applied Catalysis A: General, Vol.162, No.1-2, 71-79, 1997
A New Approach to the Pretreatment of Electroless-Plated Cu/Al2O3 Catalysts
This study employed incipient wetness impregnation to deposit palladium instead of the conventional pretreatment process to prepare the electroless plated copper catalysts of different palladium and copper loadings. The copper surface area and the copper dispersion were determined by the decomposition of nitrous oxide. Temperature-programmed reduction (TPR) was used to analyze the reducibility of oxide copper and its interaction with palladium. Different temperatures of calcination were tried in order to understand the redispersion of copper crystallites. The experimental results showed that the copper loading attained a maximum when palladium loading was 0.67 wt%. The copper surface area and the dispersion decreased with increasing calcination temperatures. At high copper loading, the redispersion of copper crystallites started at 600 degrees C, which induced the increase of the copper surface area and the dispersion. The reduction temperature of CuO decreased with the increase of palladium loading, indicating an interaction between palladium and copper.
Keywords:COPPER ALUMINA CATALYSTS;DEHYDROGENATION;CYCLOHEXANOL;SELECTIVITY;DEPOSITION;DEPENDENCE;ACIDITY