BIMETALLIC RU-CU/SIO2 CATALYSTS - EFFECT OF TOTAL SURFACE-AREA ON THE CATALYTIC PROPERTIES

Bimetallic Ru-Cu samples supported on silica gel having different surface areas have been characterized by TPR (temperature programmed reduction) and CO chemisorption. The catalytic properties have been tested in the hydrogenolysis of propane. Ruthenium and copper salts which do not contain chlorine have been used for catalyst preparation. The surface area of the supports used ranged from 25 to 500 m2/g. The Cu/Ru atomic ratio was varied between 0 and 4. Addition of Cu decreases the catalytic activity and increases the selectivity to ethane. The largest variations are observed on the support with larger surface area. It is suggested that a larger Ru-Cu interaction occurs on the smaller metal particles due to the higher tendency of the Cu atoms of populating low coordination sites.