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• Controlled pore size of Sn-SBA-15 by varied hydrothermal temperature. • Crystallite size of active phase was strongly affected by pore size. • Size effect on reducibility and metal dispersion. • Catalytic activity was significantly determined by size of active phase. • Sintering of active site and coke deposition caused the deactivation. The mesoporous Sn-SBA-15 (SSF) with varied pore size from was synthesized by changing the hydrothermal temperature, and used to disperse the PtSn oxides (PtSn/SSF) through a typical incipient wetness impregnation method. The pore size had the profound effects on porosity, particle size, the redox property, dispersion and surface chemical state etc. by applying N 2 adsorption/desorption isotherms, XRD, HRTEM, TPR, H 2 -chemisorption, XPS and in situ CO-DRIFT etc. techniques. The catalytic deactivation was mainly caused by sintering of active phase and coke deposition which was identified and quantified by combining Raman and TG analysis. The optimal pore size in this study was 8 nm, corresponding to the sample PtSn/SSF#8 over which the highest propane conversion of 46.9% and the least coke 16.8 mg C /g cat. were achieved. [Display omitted] [ABSTRACT FROM AUTHOR]

• Selective, stable and Cr-free Cu hydrogenation catalyst was reported. • Mesoporous MCM-41 benefited adsorption and diffusion of reactants. • Metal-support interaction helped stabilize vast Cu0 and Cu1+ active sites. • Cu0/Cu1+ activated H 2 while Cu1+ adsorbed the C = O bond in furfural. • 100% yield to furfuryl alcohol was achieved under 1 bar H 2 at 120 °C. Selective hydrogenation of furfural (FF) to furfuryl alcohol (FA) is a sustainable upgrading process for cellulosic carbohydrates. In this work, an inexpensive Cu catalyst was shown to clearly surpass the performance obtained under very harsh reaction conditions using the Cu-Cr industry catalyst. MCM-41 immobilized Cu species were reported as an efficient hydrogenation catalyst that can quantitatively convert FF to FA at 120 °C under 1 bar H 2. Besides this catalyst exhibited considerable stability and reusability. XRD, N 2 physisorption, TEM, H 2 -TPR, H 2 -TPD, XPS and in situ DRIFT-IR of CO adsorption were used to analyze the catalytic properties. With increasing the Cu loading (1−5 wt.%), Cu0, Cu1+ and Cu2+ species in a relatively constant fraction can be generated in the Cu/MCM-41 catalyst. One Cu species in the catalyst enabled to convert the same amount of FF per hour, and moreover, the number of active sites can well respect to the Cu loading. Cu0 and Cu1+ species as the catalytic active sites were found to be highly dispersed on the surface of ordered hexagonal mesopores of MCM-41 that may offer an abundant interface to the catalytic reaction. The metal-support interaction between active Cu species and mesoporous MCM-41 can enhance the catalytic performance under mild conditions. [Display omitted] [ABSTRACT FROM AUTHOR]