Steam reforming and water-gas shift of ethanol on Rh and Rh-Ce catalysts in a catalytic wall reactor

Ethanol is a renewable, portable, and non-toxic liquid that is a possible source of hydrogen for PEM fuel cells. This work describes an auto-thermal flat plate catalytic wall reactor for steam reforming of ethanol into H-2 and CO2, Catalytic methane combustion on Pt is coupled to ethanol steam reforming on Rh and Rh-Ce across an auto-thermal wall. At a steam/carbon ratio of 3/1 the reactor gave >99% conversion of ethanol. An H-2/CO ratio of 3/1 was obtained at a residence time of similar to100 ms and an upstream temperature of similar to800 degreesC. Methane selectivities of less than 1% were obtained with Rh-Ce. Water-gas shift was also considered in order to increase the H-2/CO ratio. The reactor was lengthened to include a cooler water-gas shift section using a Pt-Ce catalyst. The extended reactor produced >99% conversion of ethanol and an H-2/CO ratio of 30/1 at a steam/carbon ratio of 4/1. The residence time was similar to400 ins, and the upstream temperature was similar to900 degreesC in the extended reactor. The reactor was stable for at least 100 h with no detectable degradation in performance. (C) 2004 Elsevier B.V. All rights reserved.