The role of Ni sites located in mesopores in the selectivity of anisole hydrodeoxygenation

Abstract

A highly dispersed Ni catalyst with an increased number of Ni sites selectively distributed in the mesopores of HBEA has been developed and applied in anisole hydrodeoxygenation (HDO) in a continuous-flow reactor under a high WHSV (2.8 min⁻¹). The developed catalyst (Ni/BEA-OR-PH) displayed a significantly higher cyclohexane formation rate compared to the catalysts prepared by incipient wetness impregnation (Ni/BEA-IWI) and deposition–precipitation (Ni/BEA-DP) methods, which was attributed to its higher number of accessible active metal sites in mesopores. While the Ni/BEA-DP as well as Ni/BEA-OR-PH exhibited a high dispersion, a higher concentration of Ni species was located in micropores and distributed as charge-compensating cations, leading to a low concentration of high-temperature desorbed H per surface Ni, which facilitates the hydrogenolysis activity but restricts the hydrogenation of aromatics. Therefore, a high yield of BTX (benzene, toluene and xylene isomers) products was detected over Ni/BEA-DP.