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Development of an Iridium-Based Catalyst for High-Pressure Evolution of Hydrogen from Formic Acid.

ABSTRACT: A highly efficient and recyclable Ir catalyst bearing a 4,7-dihydroxy-1,10-phenanthroline ligand was developed for the evolution of high-pressure H₂ gas (>100?MPa), and a large amount of atmospheric pressure H₂ gas (>120?L), over a long term (3.5?months). The reaction proceeds through the dehydrogenation of highly concentrated aqueous formic acid (FA, 40?vol?%, 10?mol?L^-1 ) at 80?°C using 1??mol of catalyst, and a turnover number (TON) of 5?000?000 was calculated. The Ir catalyst precipitated after the reaction owing to its pH-dependent solubility in water, and 94?mol?% was recovered by filtration. Thus, it can be treated and recycled like a heterogeneous catalyst. The catalyst was successfully recycled over 10?times for highpressure FA dehydrogenation at 22?MPa without any treatment or purification.

SUBMITTER: Iguchi M

PROVIDER: S-EPMC5129464 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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Development of an Iridium-Based Catalyst for High-Pressure Evolution of Hydrogen from Formic Acid.

Iguchi Masayuki M Himeda Yuichiro Y Manaka Yuichi Y Kawanami Hajime H

ChemSusChem 20160817 19

A highly efficient and recyclable Ir catalyst bearing a 4,7-dihydroxy-1,10-phenanthroline ligand was developed for the evolution of high-pressure H2 gas (>100 MPa), and a large amount of atmospheric pressure H2 gas (>120 L), over a long term (3.5 months). The reaction proceeds through the dehydrogenation of highly concentrated aqueous formic acid (FA, 40 vol %, 10 mol L-1 ) at 80 °C using 1 μmol of catalyst, and a turnover number (TON) of 5 000 000 was calculated ...[more]

PMID: 27530918

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