Cobalt catalysts (Co–N–C) for C–O bond cleavage in lignin-derived aryl ethers and lignin†
Abstract
The transformation of lignin into value-added chemicals represents one of the relevant approaches for sustainable development. Herein, we prepared and characterized cobalt (Co–N–C) catalysts and evaluated their activity in transfer hydrogenolysis reactions using formic acid as the hydrogen donor with excellent activity and high selectivity for the C–O bond cleavage of lignin and lignin model compounds using water/ethanol or propylene carbonate as the solvents. Among them, the subnanometric Co-1 (CoIINx) catalyst was found to have a low content of cobalt of around 0.60 wt%, while demonstrating the highest activity in guaiacylglycerol-β-guaiacyl hydrogenolysis to selectively obtain guaiacol and isoeugenol.