Low Temperature Steam Reforming Catalysts for Enriched Methane Production

Methane steam reforming (MSR) is still the most competitive process for the production of hydrogen, due to the available technology and low cost. A possible shortcut to the “hydrogen economy” is based on enriched methane (EM), a gas mixture composed by hydrogen and methane, which could be employed as a fuel by exploiting existing technologies and infrastructures, with great improvement in emissions reduction. EM can be directly obtained by low temperature MSR, due to the endothermic character of the reaction, which is usually carried out at high temperature to obtain high methane conversion. An important aspect of this process is the choice of the catalyst, which should ensure the required activity, together with stability towards deactivation. A short review of the state-of-the-art catalysts for MSR is provided, with focus on both the active phase (mainly supported Ni particles) and the oxidic support properties. The attention is then focused on the current research on low temperature catalysts, including some hints to SR of oxygenated feedstocks (ethanol, glycerol, etc), where Ru and Rh are often employed. In this context, the importance of the support is underlined, especially to improve the stability towards deactivation. The attention is focused on the most studied low temperature MSR catalyst Ni/CeZrO2, with particular attention to the structural and surface properties of both active phase and support, which strongly influence the catalyst performances.