MULTICOMPONENT THIN-FILM MOLYBDATE CATALYSTS FOR THE SELECTIVE OXIDATION OF 1,3-BUTADIENE

The selective oxidation of 1,3-butadiene was examined over single and multiphase NiMoO4-MoO3 thin film catalysts prepared by reactive sputte ring. Previous studies of precipitated catalysts have indicated that s ynergism occurs for these multicomponent materials: sputtered films be haved similarly but tended to be more active and selective. XRD, LRS, XRF, XPS, SEM, and TEM were used to characterize the alpha-MoO3 and al pha-NiMoO4 thin films; for most bilayer materials, an additional phase , beta-NiMoO4 was present in an interfacial region. Selectivity for fu ran, 2(5H)-furanone, and maleic anhydride was enhanced by the preparat ion of the materials as layered films. (C) 1996 Academic Press, Inc.