Long-Term Hydrogen Production from a Methanol–Water Solution Catalyzed by an Iridium Complex

Long-term hydrogen production from a methanol–water solution was achieved by developing new reaction system employing homogeneous iridium catalyst bearing bipyridonate-type functional ligand. By optimizing the methanol:water ratio of solution, efficiency greatly improved in relation to that reported our previous studies. Additionally, effect scale investigated. It found small-scale led longer lifetime catalyst, accomplishing long-term continuous at constant rate for over 500 h. Furthermore, procedures reuse were studied. After 400 h, all volatiles removed under vacuum. This simple procedure is highly effective reactivation and catalyst. Finally, (13.7 L, 562 mmol) methanol (12.3 mL, 303 water (5.46 mmol), 800 achieved.