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Selective Hydrodeoxygenation of Lignin-Derived Phenols to Aromatics Catalyzed by Nb₂O₅-Supported Iridium.

ABSTRACT: The dominating catalytic approach to aromatic hydrocarbons from renewables, deoxygenation of phenol-rich depolymerized lignin bio-oils, is hard to achieve: hydrodeoxygenation (HDO) of phenols typically leads to the loss of aromaticity and to non-negligible fractions of cyclohexanones and cyclohexanols. Here, we report a catalyst, niobia-supported iridium nanoparticles (Ir@Nb₂O₅), which combines full conversion in the HDO of lignin-derived phenols with appreciable and tunable selectivity for aromatics (25-95%) under mild conditions (200-300 °C, 2.5-10 bar of H₂). A simple approach to the removal of Brønsted-acidic sites via Hünig's base prevents coking and allows reaction conditions (T > 225 °C, 2.5 bar of H₂), promoting high yields of aromatic hydrocarbons.

SUBMITTER: Jeantelot G

PROVIDER: S-EPMC9453801 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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Selective Hydrodeoxygenation of Lignin-Derived Phenols to Aromatics Catalyzed by Nb2O5-Supported Iridium.

Jeantelot Gabriel G Følkner Simen P SP Manegold Johanna I S JIS Ingebrigtsen Morten G MG Jensen Vidar R VR Le Roux Erwan E

ACS omega 20220823 35

The dominating catalytic approach to aromatic hydrocarbons from renewables, deoxygenation of phenol-rich depolymerized lignin bio-oils, is hard to achieve: hydrodeoxygenation (HDO) of phenols typically leads to the loss of aromaticity and to non-negligible fractions of cyclohexanones and cyclohexanols. Here, we report a catalyst, niobia-supported iridium nanoparticles (Ir@Nb2O5), which combines full conversion in the HDO of lignin-derived phenols with appreciable and tunabl ...[more]

PMID: 36092594

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