Promotional effect of Ni−Sn interaction over Ni supported on Sn-incorporated MCM-41 catalysts for CO₂ reforming of CH₄

Sintering of active Ni sites and deposition of coke remain challenging issues for catalytic dry reforming of methane. Herein, Ni supported on the Sn-incorporated MCM-41 catalysts were synthesized and tested for DRM process. The structural and physicochemical properties of fresh and spent samples were studied by N₂ adsorption-desorption, XRD, H₂-TPR, XPS, TEM, STEM-EDS, Raman, and TGA techniques. It was revealed that Sn addition improved the dispersion and decreased the size of active Ni nanoparticles by tuning the charger transfer between Ni and Sn. The formation of Ni−SnO_x interface provides more possibilities to activate CO₂. The best results were obtained by 2Ni/Sn−MCM-41 sample with the Ni/Sn mole ratio of 2 : 1, contributing CH₄ conversion of 95% and CO₂ conversion of 94% at 800 °C. Moreover, the presence of Sn increased the resistance to sintering of Ni-based catalysts during the severe conditions, thereby the Ni nanoparticle size only appeared a slight growth after 32 h TOS. Combined with the characterization of the spent 2Ni/Sn−MCM-41 sample, it was revealed that the coke deposition of the deactivated catalyst was dominated by amorphous carbon, which could be responsible for the desirable regeneration ability of the catalyst.