HIGH ACTIVE, SELECTIVE AND SULFUR RESISTANT SUPPORTED PALLADIUM TETRA-COORDINATED COMPLEX AS CATALYST IN THE SELECTIVE HYDROGENATION OF STYRENE

The [PdCl2(CH3SOCH3)(2)] complex supported on gamma-Al2O3 was studied as catalyst in the selective hydrogenation of styrene to ethylbenzene. This catalyst is considerably more active, selective and sulfur-resis tant than a conventional catalyst obtained from an acid solution of Pd Cl2. As determined by XPS and IR, the active species is the complex it self, which is stable under the reaction conditions. The complex is de stroyed, at least partially, by hydrogen treatments above 353 K, leadi ng to a less active and less sulfur resistant catalyst. The highest su lfur resistance can be attributed to electronic and geometrical effect s.