Catalytic palladium membrane for reductive oxidation of benzene to phenol

Abstract A stepwise examination for the direct synthesis of phenol from benzene was attempted to clear a so-called reductive oxidation process in the reaction system using a catalytic palladium membrane. It was suggested that the oxygen activated by the active hydrogen permeating across the palladium membrane might participate in the hydroxylation, and therefore there should be an appropriate H 2 /O 2 ratio giving a larger benzene yield. Such new information was very contributory to improve the phenol yield, which could reach ca. 20% at 473 K.