New preparation of a carbon-TiO2 photocatalyst by carbonization of n-hexane deposited on TiO2

The photocatalytic oxidation of phenol in water has been investigated over titanium dioxide (Tytanpol A 11) modified by carbon deposited via n-hexane carbonization. These catalysts were prepared through the heating at the high temperatures (400, 450 and 500degreesC) of titanium dioxide in an atmosphere of gaseous n-hexane. The catalysts have been remained at the final temperature of heat treatment for 3, 4.5 and 6 h. These resulted different carbon contents in the carbon-modified TiO2 catalysts obtained. The catalysts modified by carbon deposition had catalytic photoactivity slightly lower than that of TiO2 without carbon deposition. However, the former showed almost eight times lower turbidity of solution than the latter after photocatalyst sedimentation. These two factors depend on the carbon content and have influence on 11 practical efficiency" of catalysts. The "practical efficiency" of carbon-modified TiO2 catalysts was five times higher than that of pure titanium dioxide. Deposition of carbon on TiO2 leads to the obtaintion of a catalyst which can be easily used in water treatment system. (C) 2004 Elsevier B.V. All rights reserved.