Removing of carmoisine dye pollutant from contaminated waters by photocatalytic method using a thin film fixed bed reactor

Abstract Recently, the advanced oxidation processes have been used to treat wastewater containing various dye pollutants via various methods of purification. In this work, the removal of the Carmoisine dye from contaminated waters by a photocatalytic method in a recirculating thin-film fixed bed reactor (TFFBR) was investigated and was compared with photolysis. By the surface response method via Minitab software, the experiments were designed in such a way that the effects of different parameters on the process were studied. The effect of various parameters, for instance, pH of solution, reaction time, initial dye concentration, flow rate, hydrogen peroxide concentration on the dye removal efficiency has been investigated. By the screening and optimization stages in the response surface method, the optimal conditions for performing the process were as follows: 45 min of time, pH 2, 13.33 mM of H2O2 concentration, the flow rate of 0.25 Lmin−1, and 10 mg/L of dye concentration. The proficiency of removing color by advanced oxidation is more than 97% under optimum conditions. Graphical Abstract