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TITLE: Methanol and Methyl Fuel Catalysts. Final Technical Report, September 1980-August 1983. AUTHOR: K. Klier; R. G. Herman; G. W. Simmons. INST. AUTHOR: Lehigh Univ., Bethlehem, PA. Center for Surface and Coatings Research. SPONSOR: Department of Energy, Washington, DC. LANGUAGE: English PUB. TYPE: Technical Report PUB. COUNTRY: United States SOURCE: Department of Energy [DE], Dec 83, 109p. ABSTRACT: Copper-based catalysts for alcohol synthesis were prepared, tested for catalytic activity and selectivity, and characterized. These catalysts include Cu/ZnO, Cu/Co/ZnO, Cu/Co/Cr sub 2 O sub 3 , Cu/Co/Cr sub 2 O sub 3 /K sub 2 O, and Cu/ZnO/KOH. The low activity and selectivity, while the Cu/ZnO catalyst was verified to be a very active and selective methanol synthesis catalyst. Cobalt imparted a methanation function to the catalysts, while potassium suppressed the activity and the selectivity. Over the quaternary catalyst, higher pressure and lower GHSV enhanced the selectivity to higher alcohols. Low concentrations of carbon dioxide in H sub 2 /CO synthesis gas over Cu/ZnO catalysts promote methanol synthesis, while at high concentrations it behaves as a retardant of the synthesis. The water gas shift reaction readily proceeds over the Cu/ZnO catalyst. Analogous to the CO sub 2 effect, the presence of water in the synthesis gas has a profound effect on the synthesis of methanol. The Cu/ZnO catalyst is a good hydrogenation catalyst. Olefins, aldehydes, and acids are hydrogenated at a faster rate than CO is hydrogenated to methanol, but aromatics are hydrogenated at slower rates. Chemical trapping of the intermediates on these surface sites with amines demonstrates that a kinetically significant intermediate in methanol synthesis is a surface formyl or hydroxycarbene species. These species can be formed from synthesis gas or by alcohols in the reactant stream, and they readily alkylate amines in the reactant gas stream. Over an Fe/Cu/ZnO catalyst, amines inhibit the production of alcohols by trapping the precursor intermediates, while changing the hydrocarbon selectivity from paraffins to predominantly olefins. 68 references, 9 figures, 25 tables. (ERA citation 09:019883) REPORT NUMBER: DOE/PC/30265-T1 CONTRACT NUMBER: FG22-80PC30265 |