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 capturing the energy value of the methane produced by low-temperature reforming in an internal combustion engine, combined with use of the waste heat from the engine to heat the reformer, will close the efficiency gap between the two pathways. Vehicles powered in this way will be less expensive since a much smaller fuel cell unit is required and will benefit from the stability and low cost of low-temperature ethanol reforming. Ethanol is a sustainable fuel, derived from biomass, which will not contribute to global warming. The low-temperature reforming pathway for ethanol may therefore represent a technically and economically attractive pathway to ethanol-fueled vehicles.

A low-temperature ethanol-reforming pathway, catalyzed by copper–nickel powder catalysts, transforms ethanol into a mixture of H2, CO, and CH4 at temperatures between 300 and 350 °C. Blending 25–50% of this gas mixture, known as “low-temperature ethanol reformate”, with ethanol or E85 fuels, enables dilute engine operation, resulting in substantial improvements in fuel economy and emissions. It is thermodynamically feasible to drive low-temperature reforming with exhaust heat, but this requires an onboard reformer providing adequate heat exchange between exhaust and fuel while retaining the catalyst. Three low-temperature ethanol reformer architectures (representing a design evolution) were developed and tested at automotive scale with exhaust from a V8 engine. The best catalyst retention and heat-transfer properties were achieved by embedding the catalyst in fibrous metal media with a density gradient. Longitudinal shell-and-tube and finned tube reformers achieved effective heat transfer and adequate initial conversion but proved inadequate for vehicular applications because of high thermal mass, catalyst settling, and unacceptable pressure build. A transverse shell-and-tube design in which banks of parallel, vertical catalyst tubes extended through a transverse stack of exhaust-side heat-exchange plates exhibited sustained high conversion with low and stable fuel-side pressure throughout a 500 h test period. This design has relatively low thermal mass and can be readily packaged on a vehicle. Thus, onboard reforming of ethanol- or methanol-rich fuels appears to be a feasible pathway to improve fuel economy and emissions in light-duty vehicles.