IN-SITU NMR-STUDIES OF HYDROGEN INTERACTION WITH SUPPORTED RU-GROUP IB BIMETALLIC CATALYSTS

An in situ NMR technique was employed to study hydrogen adsorption on silica supported Ru-Group Ib bimetallic catalysts at pressures up to o ne atmosphere. Two different hydrogen-on-metal resonances, alpha and b eta, were observed. Addition of silver to Ru was found to greatly dimi nish the relative amount of the weakly bound beta hydrogen. Since silv er preferentially populates edge, corner and other defect-like sites, the weakly bound beta was correlated with low coordinated metal atoms. The total hydrogen population on the catalyst remains approximately t he same with the addition of copper. The difference in catalytic behav ior of Ru, Ru-Cu and Ru-Ag is postulated to be due to the surface segr egation induced structure sensitivity of the weakly bound beta hydroge n.