Hydrogen charging/discharging system with liquid organic compounds: A lacunar oxide catalyst to hydrogenate the unsaturated organic compound

Lacunar mixed oxides based on cerium nickel and aluminium or zirconium CeM 0.5 Ni X O Y ( M = Zr or Al), able to store high quantities of hydrogen, have been analysed in the hydrogenation of toluene into methyl-cyclohexane (MCH). When these solids present very good toluene hydrogenation activity and selectivity towards MCH in presence of H 2 , in absence of gaseous hydrogen, the reactive hydrogen species stored in the solid can hydrogenate toluene into MCH. The hydrogenation activity under helium + toluene flow decreases as a function of time and becomes nil. The integration of the curve obtained allows to determine the extractable hydrogen content of the solid used, and a value of 1.2 wt% is obtained at 80 ∘ C on a CeAl 0.5 Ni 3 O Y compound pre-treated in H 2 at 300 ∘ C . To optimise the system, different parameters have been analysed, such as the catalyst formulation, the metal content, the pre-reducing conditions as well as the reaction conditions under helium + toluene .