Screening of Ni based catalysts supported on metal oxides for liquid-phase hydrogenation of furfural to furfuryl alcohol

Abstract

Furfural, as a significant platform chemical, has established a unique connection between lignocellulosic biomass and the industry. Five types of nano metal oxide (MgO, TiO₂, SiO₂, ZrO₂ and Al₂O₃) supported Ni catalysts were prepared by facile incipient-wetness impregnation and evaluated for liquid-phase furfural hydrogenation to high-value furfuryl alcohol. Among these catalysts, Ni/MgO exhibited superior performance with a furfural conversion rate of up to 97.7% and a furfuryl alcohol selectivity of 94.7% after 2 h at 200 °C. Compared to other metal oxides, catalytic characterization results indicate that when MgO is used as the support, a NiO–MgO solid solution is formed and partially reduced by H₂ at 600 °C, resulting in highly dispersed amorphous Ni on the support surface. These factors limit the hydrogenation of the furan ring on the Ni active sites, which contributes to the high selectivity of furfuryl alcohol. Additionally, a slight decrease in catalytic activity of Ni/MgO may be attributed to formation of Mg(OH)₂ in cyclic utilization.