Influence of reactor types on photocatalytic oxidation performance of organic wastewater in slurry reactors

The technique of photocatalytic oxidation was employed in the treatment of the simulated wastewater as a model pollutant. The photocatalytic oxidation performance and kinetic of the simulated organic wastewater were investigated in a circulating slurry photocatalytic reactor and a bubble column slurry reactor. The effect of operation conditions, such as dosage of photocatalyst, illumination time, initial benzamide concentration in wastewater and gas flow rate, on the photocatalytic oxidation performance was discussed. The results showed that the application of photocatalytic oxidation in the treatment of wastewater was feasible and efficient, but it was affected by the operation conditions. The dosage of catalyst and initial benzamide concentration exist an optimum value for the photocatalytic oxidation. The results of kinetic of the photocatalytic oxidation of benzamide with different dosages of photocatalyst, initial concentrations and gas flow rates show that the photocatalytic degradation rate follows pseudo-first order kinetic. Compared with the bubble column slurry reactor, the circulating slurry photocatalytic reactor exploited in our lab provides not only an excellent blend of catalysts and reactants, but also a high efficiency of UV light. It can improve the output of treatment and reduce the dosage of catalyst.