الفهرس 
acknowledgmentOnly 14 pages are availabe for public view
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Abstract
The application of illuminated semiconductors for the remediation of water contaminants has been used for a wide range of compounds and in most cases complete mineralization was achieved. The combination of UV irradiation and oxidants or catalysts (e.g. TiO2) has attracted interest for treatment of industrial wastewater as an alternative to conventional methods. The textile residual waters create environmental problems not only due to their colour but also because some dyes (azo dyes) may undergo natural anaerobic degradation to potentially carcinogenic amines.
This work involves the photodegradation of different dyes named 2,6-dichloroindophenol, neutral red, acid black 24, indigo carmine, and eosin B by different systems (UV/TiO2, UV/H2O2, UV/Na2S2O8, and UV/NaIO4) using two different photochemical reactors. Also the work involves the regeneration efficiency studies of the preloaded F-400 granular and pulverized activated carbon with indigo carmine by the same methods.
It was found that the photocatalytic degradation and the reduction in TOC of 2,6-dichloroindophenol in the presence of irradiated TiO2 were enhanced in the presence of low concentrations of inorganic oxidants (H2O2, S2O82- and IO4-). This may be due to the trapping of the photogenerated conduction band electrons from TiO2 more efficiently than O2. On the other hand, UV/TiO2/IO4- and UV/TiO2/S2O82- systems were effective than UV/IO4- and UV/S2O82-. This may be attributed to the enhance production of .OH from TiO2 and the inorganic oxidant. It can be seen also that the photodegradation obeys a first order rate
equation and Langmuir-Hinshelwood-type behaviour can be used to describe the photodegradation reaction.