Bifunctional catalyst Fe-Co/AC for synergistic catalyzing microwave-assisted lignin hydrogenolysis

The traditional utilization of lignin mainly relies on direct combustion, which leads to low energy efficiency and environmental pollution, becoming a key bottleneck restricting the efficient utilization of all components of lignocellulose. This paper introduced a new strategy of microwave-assisted lignin hydrogenolysis over bifunctional catalyst Fe-Co/AC to achieve high-value conversion of lignin. This article firstly investigated the hydrogenolysis characteristics and product distribution patterns in the presence of Fe-Co/AC through catalyst characterization and adsorption calculation, as well as hydrogenolysis experiments. The results showed that the formation of Fe-Co alloy in the catalyst resulted in highly catalytic activity and selectivity for the hydrogenolysis process. Next, the intrinsic effects of solvent hydrogen donors and microwaves on lignin hydrogenolysis were discussed, through comparative experiments of hydrogenolysis in absence of catalyst and microwave-assisted pyrolysis. Lastly, attention was paid to calculate the adsorption characteristics and bond length changes of different substrates under metal components in order to reveal the mechanism of Fe-Co for synergistic catalyzing lignin hydrogenolysis, and to propose a potential pathway for lignin directed conversion into phenol. The findings provide a new approach for efficient bond breaking and intermediates hydrogenation of solid wastes such as lignin and plastics to obtain high value-added products.