Ru-RuO2–Nb2O5/Hβ zeolite catalyst for high-active hydrogenation of lignin derivatives at room temperature

Cyclohexanol is an important intermediate used in the synthesis of a variety of high value-added chemicals. In this work, a novel Ru-RuO2-Nb2O5/Hβ catalyst was prepared and employed to directly hydrogenate phenol to cyclohexanol at room temperature. Moreover, the influence of Nb content and the reduction time on the activity of Ru-RuO2-Nb2O5/Hβ was investigated for obtaining the catalytic mechanism as well as the structural characteristics of the catalyst. The results showed that the phenol was almost converted into cyclohexanol with a high yield of 98.2 % via 0.3 %Ru2%Nb-Hβ-1 h catalyst at 30 °C and 2 MPaH2. The high hydrogenation activity at room temperature was attributed to the Ru-RuO2-Nb2O5 interface in catalyst via TEM, XPS, H2-TPR and NH3-TPD analysis. Moreover, the DFT calculation results showed that Nb2O5 inhibited the reduction of RuO2 species, resulting in the formation of Ru-RuO2-Nb2O5 interface and the adsorption of phenol on the Ru-RuO2 interface was stronger than Ru sites.