Enhancing the efficiency of methylcyclohexane dehydrogenation of Pt/Al2O3 catalyst doped by Ga and Ce adding: Unraveling the role of oxygen vacancy

Improving the catalytic efficiency and catalyst life of Pt/Al 2 O 3 catalyst for methylcyclohexane dehydrogenation is of great significance for the study of organic liquid hydrogen storage. In this work, the promotion effects of Ga and Ce on the substantial improvement of catalytic stability and activity over the Pt / Al 2 O 3 during the methylcyclohexane dehydrogenation were investigated. The catalyst with optimizing Ga and Ce loading (1.5 wt%) exhibits ∼99.76 % selectivity and H 2 evolution rate of 2102 mol/g Pt /min at 300 °C. In 100 h long-time reaction, the conversion of methylcyclohexane remains around 75 % with no significant decrease. The characterization results show that introducing proper amount of Ga and Ce helps Ga 3+ cations incorporate into the lattice structure of CeO 2 that increase concentration of oxygen vacancies and CeO 2 reducibility in the catalyst, which boost the capability of methylcyclohexane dehydrogenation and tolerance for coke formation. Thus, the excellent stability and activity are achieved over the GaCe-modified catalyst. This study may share new light on the rational construction of highly efficient Pt-based catalysts for methylcyclohexane dehydrogenation.