Abstract: The Pd loss from the polymer-bounded palladium catalyst in the selective hydrogena-tion of 1,5,9-cyclododecatriene at 100℃ and 1.96 MPa hydrogen pressure has been studied.Theeffects of polymer supports on the Stability of catalysts were discussed. Pd dissolution wasfound to be decreased with decrease of pore radius of support. For the same polymer support,the stability of Pd was dependent on the atom i.e.O≥N>P>C. An electron-donor groupwhich linked with the ligand atom improved the stability of the catalyst. The more activeand stable catalyst can be obtained when a five-member ring between Pd and the chelateligand is formed.

Key words: Polymer-supported catalyst, Palladium, Hydrogenation