P. Du, J. Moulijn, G. Mul
Mar 10, 2006
Citations
3
Influential Citations
139
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Quality indicators
Journal
Journal of Catalysis
Abstract
The liquid-phase photolytic oxidation of cyclohexane was studied and compared with photocatalytic oxidation over TiO2 with varying wavelengths of light exposure, slurry densities, and sources and pretreatments of catalyst material. Photolytic oxidation at λ 85%). By adding a TiO2 catalyst to cyclohexane exposed at λ 95%). The activity toward ketone formation was affected by catalyst structure, with surface hydroxyl group density being the most important parameter. Based on the observed correlation between the hydroxyl group density and activity, as well as the observed negative effect of cyclohexanol addition on cyclohexanone production rate, a preliminary reaction mechanism is proposed involving the light-induced formation of surface cyclohexyl radicals, followed by formation of a peroxide intermediate and decomposition and desorption to cyclohexanone. Accumulation of cyclohexanol on the TiO2 surface is proposed to deteriorate the photocatalytic activity and to contribute to CO2 formation.