Efficient Tuning of Surface Nickel Species of the Ni-Phyllosilicate Catalyst for the Hydrogenation of Maleic Anhydride

The rational design of catalyst is vital in the hydrogenation of maleic anhydride (MA) to chemicals, for its special construction with one C═C bond and two C═O bonds. Herein, the catalyst with nickel nanoparticles (NPs), inlaid nickel phyllosilicate (Ni-PS) featured with proper Ni 0 and assembled Lewis acid sites, is proposed for the efficient hydrogenation of MA to succinic anhydride (SA) and γ-butyrolactone (GBL). The remarkable efficiency is attributed to the synergistic effect between the surface Ni 0 and the Lewis acid sites induced from partially reduced Ni and coordinatively unsaturated Ni(II) in Ni-PS. The acid sites adsorb and activate the C═C and C═O groups, whereas the Ni 0 facilitates the H 2 decomposition. In situ XPS demonstrated that the ratio of surface Ni 0 and Lewis acid sites can be modulated effectively by changing the Ni/Si molar ratio in the catalysts, and they exhibited significantly different catalytic activity in the hydrogenation of MA. Under a lower temperature, the hydrogenation activity of MA to SA linearly increases by increasing the Lewis acid sites surface area when the accessible Ni 0 surface area is enough, whereas it is primarily affected by the Ni 0 sites under high temperature for the hydrogenation of MA to GBL.