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Title: In situ infrared study of methanol synthesis from H{sub 2}/CO over Cu/SiO{sub 2} and Cu/ZrO{sub 2}/SiO{sub 2}

In situ infrared study of methanol synthesis from H{sub 2}/CO over Cu/SiO{sub 2} and Cu/ZrO{sub 2}/SiO{sub 2} The presence of Cu greatly accelerates the rate of formate hydrogenation to methoxide species, a process in which methylenebisoxy species are observed as intermediates. Cu also significantly promotes the reductive elimination of methoxide species as methanol. Thus, methanol synthesis over Cu/ZrO{sub 2}/SiO{sub 2} is envisioned to occur on ZrO{sub 2}, with the primary role of Cu being the dissociative adsorption of H{sub 2}. The spillover of atomic H onto ZrO{sub 2} provides the source of hydrogen needed to hydrogenate the carbon-containing species. Spillover of absorbed CO from Cu to zirconia facilitates formate formation on zirconia at lower temperatures than in the absence of Cu. The reductive elimination of methoxide species appears to be the slow step in methanol formation by CO hydrogenation. The lower rate of methanol synthesis over Cu/ZrO{sub 2}/SiO{sub 2} from CO as compared to CO{sub 2} hydrogenation is attributed to the lack of water formation in the former reaction, preventing facile release of methoxide by hydrolysis. The enhanced rate of methanol synthesis from CO over Cu/ZrO{sub 2}/SiO{sub 2} as compared to Cu/SiO{sub 2} is attributed to the lower energy-barrier (formate) pathway available on Cu/ZrO{sub 2}/SiO{sub 2}.
Authors: ; ;
Publication Date:
OSTI Identifier:OSTI ID: 659077
DOE Contract Number:AC03-76SF00098
Resource Type:Journal Article
Resource Relation:Journal Name: Journal of Catalysis; Journal Volume: 178; Journal Issue: 1; Other Information: PBD: 15 Aug 1998
Sponsoring Org:USDOE, Washington, DC (United States)
Country of Publication:United States
Language:English
Subject: 10 SYNTHETIC FUELS; CARBON MONOXIDE; METHANATION; HYDROGENATION; METHANOL; SYNTHESIS; COPPER; SILICON OXIDES; ZIRCONIUM OXIDES; CATALYTIC EFFECTS; CHEMICAL REACTION KINETICS