Catalysis and characterization of a rugged lead ruthenate pyrochlore membrane catalyst

A rugged lead ruthenate pyrochlore (Py, Pb2Ru2O6O') Nafion (R) 417 membrane catalyst (vertical bar NPy vertical bar) has been prepared by an in situ precipitation method and characterized by physico-chemical techniques. The Nafion((R)) 417 membrane enhanced the Py crystallization to form a stable and continuous agglomerate-like structure in the NPyj network. The cationic exchange characteristics of Nafion((R)) 417 membrane was not fully suppressed after Py modification. Catalytic performance was demonstrated for the one pot and selective oxidation of benzyl alcohol to benzaldehyde via a perruthenate (RuO4-) intermediate with 30% H2O2 (as a sacrificial co-oxidant) in a triphasic condition (i.e. CH2Cl2/NPy/H2O2). Four repeated experiments with the vertical bar NPy vertical bar entailed a weight loss of similar to 0.07% with virtually the same catalytic performance. With these inherent features, this membrane catalyst is useful in diverse research fields including organic synthesis, fuel cells, charge storage systems, etc. (c) 2005 Elsevier B.V. All rights reserved.