1995 Volume 21 Issue 6 Pages 997-1001
Liquid phase oxidation of benzene to phenol was studied using palladium / silica catalysts prepared by impregnation and ion-exchange methods. The catalyst prepared by impregnation showed high catalytic activity, but the catalyst prepared by ion-exchange showed no catalyst activity. The high catalytic performance of the former was ascribed to the presence of Cl- ions on the catalyst surface. The reaction of benzene with hydrogen peroxide revealed that hydroxyl radical produced by the decomposition of hydrogen peroxide was an intermediate in the oxidation of benzene, and that Cl- ion suppressed a side reaction between hydrogen peroxide and hydrogen supplied on the catalyst.