Probing reaction pathways on model catalyst surfaces: Vinyl acetate synthesis and olefin metathesis

PETR 5

Wilfred T. Tysoe, wtt@uwm.edu1, Feng Gao, fenggao@uwm.edu1, Yilin Wang, ywang@uwm.edu1, Florencia C. Calaza, fccalaza@uwm.edu2, and Dario Stacchiola3. (1) Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, 3210 N. Cramer St., Milwaukee, WI 53211, (2) Department of Chemistry and Laboratory for Surface Studies, University of Wisconsin-Milwaukee, 3210 N. Cramer St., Milwaukee, WI 53211, (3) Department of Chemsitry, University of Wisconsin-Milwaukee, 3210 N.Cramer Ave., Milwaukee, WI 53201
Surface science strategies are used to understand catalytic reaction pathways on model catalysts. The pathway for the synthesis of vinyl acetate from ethylene acetic and oxygen is explored on a Pd(111) single crystal, where it is shown that vinyl acetate is synthesized by reaction between ethylene and an acetate species to form a acetoxyethyl intermediate, which decomposes via a β-hydride elimination reaction to form vinyl acetate. The olefin metathesis pathway is studied on a MoAl alloy grown on a planar alumina substrate in ultrahigh vacuum, where carbene species grafted onto the surface from methylene iodide react with adsorbed ethylene to yield a cross metathesis products via a metallacyclic intermediate, in accord with the Hérisson-Chauvin mechanism
 

Catalysis and Chemistry for the Synthesis of Fuels, Chemicals and Petrochemicals
8:15 AM-12:00 PM, Sunday, August 19, 2007 Boston Park Plaza -- White Hill Rm, Oral

Division of Petroleum Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007