Two-step hydrogen transfer catalysis conversion of lignin to valuable small molecular compounds

As the major composite of biomass, lignin can be utilized as feedstock for valuable chemicals, especially phenols. Catalysis hydrogenation of lignin is an attractive route for the conversion. However, most of them require hydrogen gas under high pressure which is dangerous. Hydrogen transfer reaction provides an alternative route to degrade and hydrogenate lignin or its units to small molecular compounds. Here, a two-step method has been employed using Raney Ni and Pd/C catalysts consecutively for hydrogen transfer catalysis for lignin. The results reveal that lignin can be degraded efficiently about 90% during conversion, and the major products are phenols with ~30% in yield. It provides a new green method for converting natural lignin to valuable chemicals.