Hydrogenation of 3-hydroxypropanal into 1,3-propanediol over bimetallic Ru–Ni catalyst

Abstract

A series of Ni-based catalysts, including Ru/SiO₂, Ni/SiO₂ and Ru–Ni/SiO₂, were prepared and employed in the hydrogenation of 3-hydroxypropanal (3-HPA) to 1,3-propanediol (1,3-PDO). The catalysts were systematically characterized by means of XRD, TEM, HRTEM, SEAD, XPS, H₂-TPD, H₂-TPR and N₂-physisorption. It was indicated that the introduction of Ru onto the Ni/SiO₂ not only increased the porosity of catalyst and the degree of dispersion of Ni species but also promoted the reduction of Ni²⁺ to Ni⁰ and the generation of active hydrogen species. The catalytic performance evaluation showed that the Ru–40Ni/SiO₂ catalyst, among all others, could provide the largest yield of 1,3-PDO (above 99.0%) and highest TOF (4.70 × 10³ S⁻¹). The optimized reaction conditions over the Ru–40Ni/SiO₂ catalyst had been established as follows: reaction temperature = 80 °C, H₂ pressure = 2.0 MPa and LHSV = 0.4 h⁻¹. In consideration of its extremely low H₂ pressure and very high yield of 1,3-PDO for the hydrogenation of 3-HPA, to the best of our knowledge, the Ru–40Ni/SiO₂ catalyst appeared to be the most efficient catalyst among all others reported in the literature. The good performance enabled the Ru–40Ni/SiO₂ catalyst to be very promising in its industrial application.