| Abstract
| - Hydrogen production for application to proton exchange membrane fuel cells (PEMFCs) has been a focus of investigation globally. Ethanol as a H2 source benefits from the ready availability of infrastructure and environmental benignity in comparison with those of other hydrocarbon fuels. Thus, H2 production from ethanol has gained much attention worldwide. In this work, H2 production from ethanol steam reforming (ESR) was investigated over Pt catalysts supported on CexZr1−xO2 (x = 0.2, 0.4, 0.6, or 0.8) developed via a glycine nitrate process. The supports or catalysts were characterized by low temperature N2 physical adsorption, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), H2 temperature-programmed reduction, temperature-programmed desorption of ethanol, and catalytic performance measurements for ESR at 350-550 °C. Initial catalyst stability was also investigated. The results indicated that Pt/CexZr1−xO2 catalysts were highly active for ESR at lower temperatures, only yielding H2, CO, CH4, and CO2 as products. However, selectivity to CH4 was found around 50.0% at 350-400 °C, while selectivity of products at 450-550 °C was found close to thermodynamic control values, indirectly suggesting that ethanol first dehydrogenates on the metallic surface and then aldehyde undergoes decarbonylation, forming CO and CH4. The function of steam was to establish thermodynamic equilibria for methane steam reforming and water gas shift reactions. The high activity and good initial stability made the catalysts suitable for application to portable power generation by using a PEMFC combined with a solid oxide fuel cell or a methane internal combustion engine for capturing the energy in methane.
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