Aqueous phase catalytic hydrogenation of furfural to furfuryl alcohol over in-situ synthesized Cu–Zn/SiO2 catalysts

Highlights: • Highly selective hydrogenation of furfural to furfuryl alcohol in aqueous phase. • In-situ synthesis of silicate on SiO₂ microspheres. • Catalyst synthesized in-situ has higher activity. • Interaction between Cu and ZnO improves the stability of the catalyst. The aqueous phase catalytic hydrogenation of furfural to furfuryl alcohol is of environmental and technical advantages. In this study, a series of Cu-based catalysts supported on SiO₂ were synthesized and used for furfural hydrogenation to furfuryl alcohol. Firstly, the effect of preparation methods of Cu/SiO₂ catalysts on the structure and performance was investigated. The results indicate that, different from those by the impregnation and deposition-precipitation, the in-situ synthesized Cu/SiO₂-IS catalyst leads to the formation of silicates, increasing the dispersion and surface area of Cu and thus improving the catalytic activity. Furthermore, the addition of Zn species not only promotes the reduction of CuO and improves the dispersion of metal Cu, but also effectively prevents decarbonylation, leading to higher furfuryl alcohol selectivity. Especially, due to its good reducibility and high metal Cu surface area, the Cu–Zn/SiO₂-IS catalyst with the Cu/Zn ratio of 2/1 shows an excellent catalytic performance. So, the in-situ synthesized catalyst has a great potential as catalyst for catalytic hydrogenation of furfural to furfuryl alcohol in industry.