Highly active and stable Ni dispersed on mesoporous CeO2-Al2O3 catalysts for production of syngas by dry reforming of methane

Ni-based mesoporous mixed CeO2-Al2O3 oxide catalysts prepared by one pot Evaporation Induced Self Assembly (EISA) were tested in dry reforming of methane. The textural, structural and physicochemical properties of the catalysts were studied by N-2 adsorption-desorption, TEM-EDS, XRD and elemental analysis. The mobility of oxygen in the structure and the redox properties were investigated by OSCC measurements, TPR and in situ DRIFTS. Finally, the post-reaction samples were analyzed by TGA, RAMAN and TEM. The calcined catalysts prepared by EISA method present mesoporous structures with highly dispersed Ni in the form of NiAl2O4 spinel clusters. After reduction, small size metallic Ni particles are observed (< 5 nm). The presence of Ce in the structure interacting strongly with Al2O3 promotes the oxygen mobility and acts as sites for CO2 adsorption, increasing the activity of the catalyst and promoting the carbon removal mechanism. In absence of Ce in the mesoporous alumina support, the activity for carbon gasification is limited and C filaments accumulate inside the reactor. The same behavior occurs with CeO2-Al2O3 oxide prepared by EISA method when Ni is post-im-pregnated because of the presence of isolated larger Ni particles which promotes the decomposition of CH4. Therefore, Ni-based CeO2-Al2O3 catalysts prepared by one pot EISA method exhibited high activity and stability for the dry reforming of methane thanks to both properties which are the confinement of Ni particles and the inhibition of carbon deposition.

Automated summary

Ni-based mesoporous mixed CeO2-Al2O3 oxide catalysts prepared by one pot EISA method show high activity and stability in dry reforming of methane, attributed to the confinement of Ni particles and the inhibition of carbon deposition.