Development and Optimization of a TiO2-Coated Fiber-Optic Cable Reactor: Photocatalytic Degradation of 4-Chlorophenol

Abstract

We have developed, characterized, and utilized a photochemical reactor system that employs an optical fiber cable as a means of light transmission to solid supported TiO_2. Light energy is transmitted to TiO_2 particles, which are chemically anchored onto quartz fiber cores, via radial refraction of light out of the fiber. Operational factors that influence the efficiency of the bundled-array optical fiber reactor are as follows: the uniformity and extent of light propagation down the fiber, the degree of light absorption by the TiO_2 coating of the refracted light, and the ability of the chemical substrates to diffuse into the TiO_2 coating. A TiO_2 coating layer that minimizes the interfacial surface area of the quartz core and TiO_2 particles and operation with incident irradiation angles near 90" enhance light propagation down the fibers. A maximum quantum efficiency of Φ = 0.011 for the oxidation of 4-chlorophenol was achieved. This can be compared to a maximum quantum efficiency of Φ = 0.0065 for 4-chlorophenol oxidation in a TiO_2 slurry reactor operated under similar conditions.