Reversible Dehydrogenation-Hydrogenation of Cyclohexanol-Cyclohexanone Pair Over Ru/Hierarchical Zeolite Catalyst

We report a reversible dehydrogenation-hydrogenation of cyclohexanol-cyclohexanone pair over Ru supported on Hierarchical Zeolite (Ru/HZ4A) under neat conditions. The catalyst Ru/HZ4A demonstrated high activity for both dehydrogenation of cyclohexanol to cyclohexanone (at 160°C) and hydrogenation of cyclohexanone back to cyclohexanol (60°C) with appreciably high selectivity and conversion. Moreover, the catalyst Ru/HZ4A displayed high durability under bulk and recyclability experiments, achieving hydrogen productivity as high as 156 L_H2/g_Ru (STY 89 mmol_H2/g_Ru/h). The developed protocol was also applied to 5-membered and 8-membered cycloalkanol-cycloalkanone pairs with excellent selectivity for a one-pot reversible dehydrogenation-hydrogenation cycle. These findings underscore the potential of the developed catalytic system for a reversible hydrogen storage system.