Naphthalene Hydrogenation Saturation over NiP/AlO Catalysts Synthesized by Thermal Decomposition of Hypophosphite.

A series of NiP/AlO catalysts with different NiP loadings were synthesized via thermal decomposition of hypophosphite and employed for naphthalene hydrogenation saturation. Results showed that NiP loading greatly affected NiP particle size and the number of active sites of the as-synthesized catalysts, which was derived from the variable interaction between POx and AlO. When the hydrogenation saturation reaction was performed at 300 °C, 4 MPa, a H/oil volume ratio of 600, and a liquid hourly space velocity (LHSV) of 3 h, 98% naphthalene conversion and 98% selectivity to decalin were achieved over NiP/AlO catalysts with 10 wt % NiP. The superior naphthalene hydrogenation saturation performance was ascribed to the large specific surface area (169 m·g), small NiP particle size (3.8 nm), and the high number of exposed active sites (CO sorption 30 μmol·g), which were beneficial to the adsorption and diffusion of the reactant molecules on the catalyst.