Acidic site regulation of supported Pt-Cu alumina catalyst with bimetallic synergistic effect achieved high catalytic activity, selectivity, and stability in the dehydrogenation of perhydrodibenzyltoluene

Dibenzyltoluene (DBT) is one of the most promising hydrogen storage media of liquid organic hydrogen carriers (LOHCs), but it is difficult to solve the problems of low catalyst selectivity and deactivation caused by the high by-products of dehydrogenation. This study designed the Pt _2.0 Cu _0.1 /Al ₂ O ₃ -900 ℃ catalyst that could balance high activity, selectivity and stability of the dehydrogenation of perhydrodibenzyltoluene (18H-DBT). This method involved appropriate acid pretreatment of the Pt-Cu synergistic effect catalyst doped with Cu, which exhibited excellent spatial confinement. This reduced the total acidity of highly dispersed nanoparticles (NPs) and increases the number of strong acid sites. The XPS, HRTEM and Py DRIFT results demonstrated that the electronic effect of Pt-Cu was more significant, and the interaction between Pt and Cu was strengthened. However, the weakening effect of strong metal-support interation (SMSI) was reduced, which decreased the excessive secondary reaction. Dynamics and mechanism studies had shown that substrate of 18H-DBT was more easily taken away by the unique electron transfer structure of Pt-Cu to form carbocations. This was accompanied by dehydrogenation without receptors of internal hydrogen transfer, reducing reaction energy barrier.