Comparing the photocatalytic process efficiency using batch and tubular reactors in removal of methylene blue dye and COD from simulated textile wastewater

Abstract

The aim of this study was photocatalytic degradation of methylene blue (MB) dye using titanium dioxide nanoparticles simulated using ultraviolet in batch and tubular reactors. In this study, the effect of different concentrations of titanium dioxide nanoparticles in the photocatalytic process on MB degradation was examined in batch and tubular reactors. The effect of dye concentration, titanium dioxide nanoparticle concentration and aeration level were examined on the process efficiency. Results showed that the removal of MB dye was directly related to the radiation time. The best removal efficiency of dye and chemical oxygen demand (COD) in the batch reactor was 100% and 42.2%, respectively, while it was 93% and 47.8% in the tubular reactor (in 1.2 g/L of titanium dioxide nanoparticles at 60 min). Moreover, as dye concentration increased, dye removal rate decreased. Making use of the batch model to remove dye and COD is more efficient and can be used on a larger scale due to the required removal efficiency and wastewater discharge standards.