Exploration of high-value pathways for lignin: From catalyst preparation to product development

Considering the facts of fossil fuel depletion and environmental issues, the conversion of biomass into high value-added chemicals is of great importance. In this work, Ni and Co were encapsulated in lignin-derived phenolic resin spheres to obtain NiCo@LRS, which was then employed as a sacrificial template for the synthesis of the bimetallic catalyst NiCo@LC-RS. The Ni and Co act as the acid and dehydrogenation sites for the catalytic transfer hydrogenolysis of 2-phenoxy-1-phenylethanol (pp-ol) and corncob lignin, respectively, and exhibit a synergistic enhancement effect. Under the optimal conditions of 170 °C, 1 MPa N₂ and 4 h, the conversion of pp-ol reached 99.9 %, with the yields of cyclohexanol and ethylbenzene at 99.9 % and 93.8 %, respectively. The lignin was completely converted and the selectivity of monophenols was 55.74 %. The catalyst remained stable and reusable after 5 cycles. Furthermore, lignin oil can be employed in the preparation of NiCo bimetallic catalysts, which have been demonstrated to exhibit excellent catalytic properties. This work provides practical guidance for the high-value utilisation of lignin.