Ethanol Steam Reforming to Produce Hydrogen Over Co/ZnO and PtCo/ZnO Catalysts

Abstract

In this study, hydrogen production using ethanol steam reforming (ESR) over monometallic Cox/ZnO and bimetallic PtyCo10/ZnO catalysts was investigated. Cox/ZnO (5, 10, 15 and 20 wt% Co) and PtyCo10/ZnO catalysts (0.1, 0.5 and 1.0 wt% Pt and 10 wt% Co) were prepared by the incipient wetness impregnation (IWI) method. The catalytic activity of the ESR was evaluated in a fixed-bed reactor under 22,000 h−1 gas hourly space velocity and an H2O/EtOH molar ratio of 13. According to the results we find that the optimum loading of Co10/ZnO catalyst exhibited higher surface area and better catalytic activity for the ESR reaction. Further, in order to understand the catalytic performance over Co-based catalysts for the ESR reaction, other focused on the effect of Pt loading. The Pt0.5Co10/ZnO catalyst showed the best intimately mixed and synergistic effect, combining the advantages of the Pt and Co catalysts, respectively, i.e. Pt was active for the dehydrogenation of ethanol and decomposition of acetaldehyde at temperatures lower than 300 °C; Co was active for the reforming of acetaldehyde. The product distribution showed that good performance was achieved at 325 °C with a composition of H2/CO2/CH4/CO equal to 73.2/23.8/2.4/0.6 %. The Pt0.5Co10/ZnO catalyst shows high catalytic activity at 325 °C with a composition of H2/CO2/CH4/CO equal to 73.2%/23.8%/2.4%/0.64%.