Kinetics of photocatalytic oxidation of oxalic acid

Abstract

The photocatalytic oxidation of oxalic acid in aqueous suspension of TiO 2 has been investigated. Based on the data obtained the reaction mechanism was proposed. The reaction efficiency is affected by the pH of the suspension, amount of catalyst and the presence of hydrogen peroxide. It was found that the initial concentration of oxalic acid does not affect the reaction rate above 1 × 10 -3 mol dm -3 of H 2 C 2 O 4 at constant pH value and fixed TiO 2 amount. Degradation rate of oxalic acid decreases as the pH of the solution increases from pH 1.3 and no degradation was detected above pH 6. Increasing of the amount of TiO 2 results in an increase of the rate of photooxidation. Addition of hydrogen peroxide also increases the destruction of oxalic acid.