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Selective Lignin Depolymerization via Transfer Hydrogenolysis Using Hydrotalcite Supported Palladium – Model Compounds to Application
The cleavage of lignin ether bonds via transfer hydrogenolysis remains a promising route for the valorization of lignin. To make this process efficient, a method would need to be developed that utilizes mild conditions and a renewable hydrogen donor solvent, in addition to avoiding high pressure of hydrogen. Herein, we demonstrate the efficient catalytic transfer hydrogenolysis of lignin model compounds possessing aromatic ether bonds, including α-O-4, β-O-4 and 4-O-5 linkages, using Pd-doped hydrotalcites as heterogeneous catalysts and ethanol as the hydrogen donor. Catalysts that can carry out transfer hydrogenolysis and decarbonylation in tandem are yet to be reported. Quantitative conversions and yields were realized for all model compounds studied, demonstrating the utility of the metal-doped hydrotalcites for this catalytic application. The system was applied to whole pine biomass to achieve delignification (86%) and a phenolic monomer yield of 39%.
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- Award ID(s):
- 1805080
- PAR ID:
- 10388726
- Date Published:
- Journal Name:
- ChemRxiv
- ISSN:
- 2573-2293
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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