This proposal addresses the one-step direct electrochemical synthesis of propylene oxide from propylene/oxygen mixtures and a bifunctional electrocatalyst for simultaneously generating hydrogen peroxide and epoxidizing olefins. The ability to in situ electrochemically generate hydrogen peroxide allows for the precise control of its local concentration and the resultant enhancement of selectivity to propylene oxide. The proposed approach will also allow for direct removal of product through a membrane semipermeable to propylene oxide. Hydrogen peroxide electrogeneration will be catalyzed by either gold or a supported metallomacrocycle (Ni-phthalocyanine or Comeso-tetraphenylporphyrin). Propylene epoxidation will be catalyzed by Mn-meso-tetraphenylporphyrin or titanium silcalite. Successful completion of the program will result in a selective, high yield process for the epoxidation of olefins. The technology developed in this program should provide a significantly lower cost route to olefin epoxides using in situ electrochemically generated hydrogen peroxide and should be of great interest to manufacturers of these types of materials.
