THE EFFECT OF COPPER ON THE REACTION OF ETHYLENE ON SILICA-SUPPORTED RU-CU CATALYSTS AS STUDIED BY C-13 NMR

The adsorption and reaction of ethylene on silica-supported bimetallic RuCu catalysts has been studied by solid state, highresolution13C NMR in order to elucidate the effect of copper on the catalytic behavior. Copper itself exhibits no inherent activity for the reaction of ethylene whereas Ru is highly active, producing dimeric products (butenes and butanes) and ethane. The ability to form dimeric products is not changed by the introduction of copper into the metal particles. However, the bimetallic catalysts have significantly less hydrogenation capabilities than the supported monometallic ruthenium catalyst. Since copper is known to populate low-coordination, defect-like lattice positions such as edges and corners, it is postulated that these sites play a crucial role in hydrogenation reactions. © 1990 J.C. Baltzer A.G. Scientific Publishing Company.