Thin-film fixed-bed reactor for photocatalytic degradation of synthetic food dye Sunset Yellow from contaminated waters and optimisation of process by response surface method

Abstract

ABSTRACT In recent years, the advanced oxidation processes have been used to treat wastewater containing various dye pollutants through various methods of purification. In this study, the removal of the Sunset Yellow (SY) dye from contaminated water was investigated by UV/TiO2/H2O2 process using a recirculating thin-film fixed-bed reactor (TFFBR). The experiments were designed by the response surface method (RSM) via Minitab software, in such a way that the effects of various parameters on the process are investigated. The effect of different parameters such as reaction time, pH of the solution, initial dye concentration and hydrogen peroxide concentration on the dye removal efficiency has been investigated. According to the results of the screening and optimisation test by the response surface method, the optimal conditions for performing the process were, time of 45 min, pH of 2, hydrogen peroxide concentration of 13.33 mM and initial dye concentration of 10 mg/L. Under optimal conditions, the efficiency of dye removal was more than 97%. Besides, the kinetics of SY dye removal followed the first-order equation.