Low-Temperature Reforming of Ethanol over Copper-Plated Raney Nickel: A New Route to Sustainable Hydrogen for Transportation

Abstract

Raney nickel can be plated with a high loading of copper (28%) to produce a novel copper−nickel catalyst, which retains a Raney-type structure. A simple two-step aqueous procedure was used. The catalyst exhibits high activity for low-temperature (250−300 °C) reforming of ethanol to methane, carbon monoxide, and hydrogen. Stable activity for over 400 h was achieved with no detectable methanation. The catalyst is significantly less active for methanol reforming and has low water−gas shift activity. The kinetics fit a two-step model in which ethanol is dehydrogenated to acetaldehyde in a first-order reaction with an activation energy of 149 kJ/mol followed by the decarbonylation of acetaldehyde, which is also first-order. The low-temperature ethanol reforming pathway has not previously been considered as a route to hydrogen for fuel cell vehicles because it leads to formation of only 2 mol of hydrogen/mol of ethanol versus 6 mol of hydrogen for traditional, high-temperature reforming. We suggest that capturi...