No abstract

A series of g-Al 2 O 3 -supported nickel-based catalysts were evaluated in continuous hydrogenation of toluene. Sr-and poly(ethylene glycol) 800 (PEG800)-modified Ni/g-Al 2 O 3 catalysts provided the best activity with high conversion of toluene and selectivity for methylcyclohexane which was ascribed to the addition of Sr and PEG800 during the preparation process, resulting in smaller and highly dispersed Ni species on the surface and in the pores of g-Al 2 O 3 . Furthermore, the formation of SrCO 3 and NiAl 2 O 4 is believed to be advantageous for the dispersion and stabilization of the active Ni species, accounting for its good stability.

No abstract

No abstract

The oxidant-free dehydrogenation of n-pentanol over copper based catalysts was investigated in this paper. The effect of metal modification on the activity and stability of the copper catalyst supported on γ-Al 2 O 3 and La 2 O 3 (Cu/γ-Al 2 O 3 -La 2 O 3 ) was clarified and a Cr modified Cu/Al 2 O 3 -La 2 O 3 (Cu-Cr/γ-Al 2 O 3 -La 2 O 3 ) showed the best catalytic performance. The conversion of n-pentanol was 70.0% and the selectivity for n-pentanal increased to 97.1% over Cu-Cr/γ-Al 2 O 3 -La 2 O 3 . X-ray diffraction and temperature programmed reduction of H 2 indicated that the addition of Cr favors the formation and reduction of the copper oxide, and the dispersion of the active Cu 0 species, accounting for the good activity and stability of this catalyst. Furthermore, the lower amount of acidic sites in Cu-Cr/γ-Al 2 O 3 -La 2 O 3 is suggested to suppress the dehydration in oxidant-free dehydrogenation of n-pentanol, accounting for the higher selectivity for n-pentanal.