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• Pt@HA exhibited excellent catalytic selectivity in hydrogenation of quinoline via hydrogen spillover. • Spillover process discriminated the hydrogenation of pyridine and benzene moiety in quinoline molecule. • Hydroxyl groups on HA zeolite strengthened adsorption of pyridine moiety to facilitate its hydrogenation process. Hydrogen spillover has been widely used in heterogeneous catalysis, yet how to explore the potential of catalyst support to further promote catalytic function of hydrogen spillover has rarely been investigated. Herein, platinum encapsulated into amorphized HA zeolite (denoted as Pt@HA) with generated hydroxyl groups was used as model catalyst to study the role of HA zeolite support on the promotion of catalytic performance in hydrogenation of quinolines to tetrahydroquinolines. Benefiting from small pore size of amorphized HA zeolite to prevent direct interaction of quinoline with encapsulated platinum, Pt@HA showed good catalytic selectivity in this transformation through hydrogen spillover. This remarkable catalytic selectivity was resulted from the interaction of hydroxyl groups at surface of HA zeolite with pyridine moiety through the formation N H bond to facilitate adsorption to make much lower apparent activation energy of Pt@HA for hydrogenation of pyridine moiety than that of benzene moiety, thus exhibiting enhanced catalytic selectivity. [Display omitted] [ABSTRACT FROM AUTHOR]

Design of heterogeneous catalyst to achieve efficient conversion of biomass to high added-value chemicals is still very attractive. Herein, taking industrially important selective hydrogenation of furfural to furfuryl alcohol as an example, the designed amorphized HA zeolite encapsulation of platinum clusters (denoted as Pt@HA) exhibited excellent catalytic selectivity at totally conversion of the reactant furfural, along with good reusability and poison resistance ability. The selected amorphized HA zeolite with very small pore size constrained the reactant furfural to be reacted through hydrogen spillover process at zeolite surface, instead of to be adsorbed and activated onto Pt surface. Resulting from the stronger interaction between nucleophilic oxygen atom of aldehyde group and acid site at HA zeolite surface than that of furan ring group, furfural preferred to adsorb onto Pt@HA surface with the end of aldehyde group rather than the end of furan ring group, thus facilitating the spilled H atom to react with aldehyde group to give desired furfuryl alcohol product exclusively. [Display omitted] • Pt@HA exhibited remarkable catalytic property in hydrogenation of furfural to furfuryl alcohol via hydrogen spillover. • Spillover process disfavored activation of aldehyde group and furan ring simultaneously in one furfural molecule. • Acid sites on HA zeolite surface promoted adsorption of aldehyde group to facilitate its hydrogenation process. [ABSTRACT FROM AUTHOR]