A Photocatalytic Ti02 Anode and Membrane Reactor for the Enhanced Destruction of Chioro-Organic Compounds in Water

50176-98-I A Photocatalytic Ti02 Anode and Membrane Reactor for the Enhanced Destruction of Chloro-Organic Compounds in Water--CeraMem Corporation, 12 Clematis Avenue, , Waltham, MA 02154-7011; (781) 899-4495 Dr. Kenneth E. Fickie, Principal Investigator Dr. Robert Goldsmith, Business Official DOE Grant No. DE-FG02-98ER82547 Amount: $75,000 Excessive electron-hole recombination in a membrane reactor prevents effective use of photogenerated holes, which are needed to subsequently react with the titania surface to form the oxidizing hydroxyl radicals necessary for destroying organic or chloro-organic compounds. Methods using adsorbed oxygen to scavenge electrons that participate in the recombination reaction are slow, which then keeps the photo destructive efficiency low. By eliminating this inefficiency, the transport of wastes and reaction products to and from the surface of the titania (TiO2) anode can become rate limiting. Reactor design, is also important. This project will develop a two-layer, titania-based, composite photoanode which (a) can readily drain UV-generated conduction band electrons to an electrical sink, and (b) can support perpendicular flow of reactants and products. The concept presented is readily manufacturable and cost-effective for producing photoanodes on a variety of porous, high-surface-area substrates. Specific objectives of this project are to: (1) fabricate the desired photoanode, (2) test its ability to completely mineralize a typical chloro-organic compound in water, and (3) evaluate and compare its destructive performance against that of other known immobilized photocatalytic methods which use titania. Commercial Applications and Other Benefits as described by the awardee: Immediate commercial applications lie in the remediation of contaminated ground-water and in the cleanup of dilute low volume industrial and small shop outflows. Of particular interest to the government and to private industry is the cost effective removal of halogenated organic materials from those waters. _