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Updated: Nov 25, 2025
Hydrogen Production and Utilization in a Membrane Reactor
Published on: March 10, 2023
Hydrogen Production from Methanol-Water Mixture over Immobilized Iridium Complex Catalysts in Vapor-Phase Flow
Sho Yamaguchi1,2, Yoshifumi Maegawa1, Ken-Ichi Fujita3
1Toyota Central R&D Laboratories, Inc., Nagakute, Aichi, 480-1192, Japan.
Abstract:
CO-free hydrogen production from methanol and water by using transition metal complex catalysts has attracted increasing attention. However, liquid-phase batch reactions using homogeneous catalysts are impractical for large-scale operations, owing to the consumption of bases and the use of organic solvents or additives. This study concerns a novel method for continuous hydrogen production from a simple methanol-water solution under vapor-phase flow. The reaction is catalyzed by an anionic iridium bipyridonate (Ir-bpyd) complex immobilized on a periodic mesoporous organosilica. The liquid-phase batch reaction using homogeneous anionic Ir-bpyd complex is immediately deactivated, owing to CO2 generation, whereas no catalyst deactivation is observed in the vapor-phase flow reaction because CO2 is smoothly removed from the catalyst bed, enabling continuous hydrogen production without the addition of a base. Thus, the critical problems pertaining to homogeneous catalysts are overcome.
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