Synthesis and characterization of Cu/ZnO/Al2O3 catalyst by different methods and investigation of performance in methanol steam reforming for hydrogen generation

Today's world has environmental issues such as climate change and greenhouse gas emission due to the fossil fuels usage. These environmental concerns and fast depletion of fossil fuel resources increased the research for the production of hydrogen from alternative and renewable sources. Proton exchange membrane fuel cell system is a promising power generation technology fed by hydrogen as an environmentally friendly and sustainable solution. In this regard, hydrogen production through methanol steam reforming reaction (MSR) has the potential to be an appropriate method with the advantages of having low amount of carbon monoxide, no sulphur production so that there is no requirement for desulfurization, having good energy density, relatively high H/C ratio and low reforming temperature. However, endothermic nature of the reaction and not having comprehensive distribution infrastructure are drawbacks of this process. MSR is based on reaction of methanol and steam with the help of catalyst and releases hydrogen and carbon dioxide. The catalyst activity and selectivity are the properties, which can be enhanced by the structure of the catalyst. In this study, in order to obtain a catalyst having better structure and catalytic behavior, which exhibits high specific surface area, high metal dispersion and higher activity for H2 production, the effect of preparation methods on the structure and catalytic behavior of Cu/ZnO/Al2O3 were investigated. Conventional coprecipitation, sequentially coprecipitation and ball milling methods were studied. The results show that the catalysts obtained by sequentially coprecipitation has a high specific surface area and dispersion giving a higher activity which promotes the superior catalytic performance depending on formation of active copper material with higher copper specific surface and a stronger Cu–ZnO synergy thanks to proper incorporation of zinc oxide species into precursors.