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Hydrogen (H 2 ) was produced by aqueous-phase reforming of biomass-derived oxygenated hydrocarbons at temperatures near 500 kelvin over a tin-promoted Raney-nickel catalyst. The performance of this non–precious metal catalyst compares favorably with that of platinum-based catalysts for production of hydrogen from ethylene glycol, glycerol, and sorbitol. The addition of tin to nickel decreases the rate of methane formation from C-O bond cleavage while maintaining the high rates of C-C bond cleavage required for hydrogen formation.

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Aqueous-phase reforming of 10 wt% ethylene glycol solutions was studied at temperatures of 483 and 498 K over Pt-black and Pt supported on TiO 2 , Al 2 O 3 , carbon, SiO 2 , SiO 2-Al 2 O 3 , ZrO 2 , CeO 2 , and ZnO. High activity for the production of H 2 by aqueous-phase reforming was observed over Pt-black and over Pt supported on TiO 2 , carbon, and Al 2 O 3 (i.e., turnover frequencies near 8-15 min ÿ1 at 498 K); moderate catalytic activity for the production of hydrogen is demonstrated by Pt supported on SiO 2-Al 2 O 3 and ZrO 2 (turnover frequencies near 5 min ÿ1); and lower catalytic activity is exhibited by Pt supported on CeO 2 , ZnO, and SiO 2 (H 2 turnover frequencies lower than about 2 min ÿ1). Pt supported on Al 2 O 3 , and to a lesser extent ZrO 2 , exhibits high selectivity for production of H 2 and CO 2 from aqueous-phase reforming of ethylene glycol. In contrast, Pt supported on carbon, TiO 2 , SiO 2-Al 2 O 3 and Pt-black produce measurable amounts of gaseous alkanes and liquid-phase compounds that would lead to alkanes at higher conversions (e.g., ethanol, acetic acid, acetaldehyde). The total rate of formation of these byproducts is about 1-3 min ÿ1 at 498 K. An important bifunctional route for the formation of liquid-phase alkane-precursor compounds over less selective catalysts involves dehydration reactions on the catalyst support (or in the aqueous reforming solution) followed by hydrogenation reactions on Pt.

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