A novel Pd/Al2O3@ZIF-8 core-shell catalyst was successfully prepared by ZnO-induced coating of a layer of ZIF-8 shell over the Pd/Al2O3 bead with a mean diameter of 1—2 mm. The obtained Pd/Al2O3@ZIF-8 core-shell catalyst was characterized by XRD
EDX
SEM and ICP analysis techniques
and employed as catalyst for the liquid-phase hydrogenation of alkenes. It was found that the introduction of ZnO layer and subsequent pretreatment of the ZnO layer played vital roles in the formation of continuous and compact ZIF-8 shell. Furthermore
the thickness of the ZIF-8 shell could be tuned by altering the assembly cycles of ZIF-8. Results of the catalytic reactions showed that the Pd/Al2O3@ZIF-8 catalyst exhibited better size-selectivity
poison-resistance and leaching-proof properties in contrast to the naked Pd/Al2O3 catalyst.