Effect of pH and temperature on degradation of dilute dihydroxybenzene, in aqueous titanium dioxide suspension irradiated by UV light

The degradation of p-dihydroxybenzene in a batch photocatalytic reactor, irradiated by a high intensity UV lamp, was investigated. In this experimental work, commercial anatase titanium dioxide (degussa P 25) was used as a catalyst. Various operating conditions such as initial concentration, pH of the solution, temperature, addition of H(2)O(2), bubbling of oxygen, and catalyst loading were examined. A pseudo-first-order kinetics was observed with a rate constant ranging between 17.1 x 10(-3) and 5.6 x 10(-3) min(-1) which was decreasing with increasing initial concentration. H(2)O(2) enhanced the degradation significantly. For the experimental conditions, there was no significant effect for the added catalyst dosage. The degradation rate of p-dihydroxybenzene increased to a certain amount with increasing temperature then decreased. Further experimentation is needed to verify this observation. (C) 2008 Elsevier B.V. All rights reserved.