Structures and synergistic catalyses of FeRu/Al2O3 catalysts derived from FexRu3–x(CO)12(x= 0, 1, 2, 3). Part 2.—Structures and catalyses of FeRu catalysts reduced with H2

Abstract

Al2O3-supported FeRu bimetallic catalysis prepared by thermal treatment of FexRu3–x(CO)10(H)(OA1 < )(x= 0, 1, 2, 3) have been found to show synergistic catalyses in C2H4 self-homologation and C2H6 hydrogenolysis reactions and to provide C2–C5 alkenes with good selectivities in CO hydrogenation as compared with corresponding impregnation catalysts. The structures of the bimetallic catalysts have been studied by means of X-ray absorption fine structure spectroscopy. The Ru atoms are attached to the Al2O3 surface through Al—O—Ru direct bonds forming Ru clusters, and the Fe atoms are also attached to the surface through surface oxygens adjacent to the Ru clusters. The size of the Al2O3-attached Ru clusters and the number of adjacent Fe atoms reflect the original cluster compositions. These metal–surface oxygen bonds prevent the undesirable aggregation of large metal particles of the surface segregation of the Fe component over the Ru clusters.