Towards maximizing conversion of ethane and carbon dioxide into synthesis gas using highly stable Ni-perovskite catalysts

Dry ethane reforming (DER) aims to utilize captured CO2 and ethane, which is found in large quantities in shale gas, towards the production of high-value synthesis gas. During the dry reforming of hydrocarbons, the interaction between the active metal and the underlying support, along with the choice of the operating temperature, are considered to be the main factors influencing a catalyst's stability and coking resistance. In this work, the DER catalytic performance and stability of Ni-doped perovskite systems is compared with that of a typical impregnated Ni/Al2O3 catalyst. The calcined, reduced and spent catalysts are assessed using the ICP, XRD, N2 physisorption, H2-TPR, CO2-TPD, TEM, HAADF-STEM, EDS Mapping, XPS and TPO techniques. Ni-CaZrO3 (CZNO) consisting of partly exsolved Ni nanoparticles with a strong metal-support interaction is shown to be particularly stable and accumulate only a fraction of the coke that is deposited on the impregnated Ni/Al2O3 catalyst, which suffers from severe and rapid degradation under the reactant stream. By increasing the operating temperature to 750 °C, Ni-CaZrO3 can achieve almost total conversion of ethane and around 90% conversion of carbon dioxide towards synthesis gas, with no apparent loss of catalytic activity.