Assessment of photocatalytic n-TiO2/UV and n-TiO2/H2O2/UV methods to treat DB 86, RY 145 and AV 90 dye mix containing wastewater

Abstract

This study examined and compared the n-TiO2/H2O2/UV and n-TiO2/UV processes to remove the content of synthetic wastewater containing Direct Blue (DB86), Reactive Yellow (RY145) and Acid Violet (AV90) dye mix. The optimum parameters for both processes have been determined as pH 3, 125 mg/L n-TiO2 and 45 min, and the H2O2 dose has been specified as 750 mg/L in the n-TiO2/H2O2/UV process. While the removal efficiencies were 54.38% at 436 nm, 44.20% at 525 nm and 85.72% at 620 nm for the n-TiO2/UV process, 90.63% at 436 nm, 92.27% at 525 nm and 99% at 620 nm were obtained for n-TiO2/H2O2/UV process. With H2O2 addition to the process, treatment efficiencies have been increased drastically. Moreover, due to the results of the kinetic analyses for both processes, the pseudo-second-order was observed to be the most appropriate kinetic model, depending on the regression coefficient in color removal.