Mild Hydrogenation of Lignin Depolymerization Products Over Ni/SiO2 Catalyst

Many efficient methods have been proposed to realize lignin depolymerization, while effective usage of lignin depolymerization products at mild conditions is still a big challenge. Conversion of them to stable products in thermal and chemical properties is a necessary step. Herein, a mild hydrogenation process of lignin depolymerization products over Ni/SiO2 catalyst was proposed. Model compound of 2,3-dihydrobenzofuran exhibited a good reaction result. Nearly 100% conversion was obtained at 130 degrees C, and the selectivity of 2-ethylcyclohexanol product reached 94.6%. The lignin depolymerization products also had a good hydrogenation result, in which not only the hydrogenation of unsaturated groups but also the cleavage of beta-O-4 bonds occurred. Stable products in thermal and chemical properties were formed, which possessed high heated value and low molecular weight. This treatment is conducive to suppressing the occurrence of condensation and favorable for the further catalytic conversion.