Photocatalytic Degradation of 1,3-Dihydroxy-5-methoxybenzene in Aqueous Suspensions of TiO2: An Initial Kinetic Study

Photocatalytic degradation of 1,3-dihydroxy-5-methoxybenzene (1,3-DHMB) is investigated in the presence of TiO2. Effects of initial concentration of 1,3-DHMB, pH of the medium, irradiation time, and temperature are examined. Degradation of 1,3-DHMB obeys zero-order kinetics. Following the formation of CO2, the reaction rate constant, k, is found as 217 μmol m−3 s−1 and the adsorption constant, K, is found as 4.22 m3 mol−1. The highest degradation of 1,3-DHMB and the highest concentration of CO2 are both obtained at pH 9.0. The apparent activation energy is calculated as 17.1 kJ/mol. For the route of degradation, a mechanism is postulated.