Development of a new photocatalytic reactor for water puri®cation

The puri®cation of water by heterogeneous photocatalysis is one of the most rapidly growing areas of interest to both research workers and water puri®cation plants. Recent literature has demonstrated on a laboratory scale the potential of this promising technology to completely destroy organic pollutants dissolved or dispersed in water into harmless substances. However, to date no viable pilot plant exists using this technology. New reactor design ideas are necessary that must be able to address the two most important parameters, namely, light distribution inside the reactor through the absorbing and scattering liquid to the catalyst, and providing high surface areas for catalyst per unit volume of reactor. In this paper, a new reactor design addressing the solution to both the above problems is proposed for water treatment. The reactor consists of several hollow tubes coated on its outside surface with the catalysts. The hollow tubes have been employed as a means of light delivery to the catalyst. Experiments performed in a reactor containing 54 densely packed hollow tubes of 0.006 m diameter showed promising results. The new reactor aims at developing a technical solution to the design of a commercial photocatalytic reactor. # 1998 Elsevier Science B.V.