Comparative Study on Removal of Acid Violet 90 dye by using Catalytic Ozonation Processes with n.CeO2, n.ZnO and n.CeO2/n.ZnO Nanocatalysts and Kinetic Examination

Abstract

The textile industry uses high amounts of water and dyestuffs, and accordingly, wastewater containing significant amounts of dyestuffs is produced, which have to be treated before being discharged to the environment. The aim of this study is the treatment of synthetic wastewater containing 50 mg/L Acid Violet 90 dyestuff with catalytic ozonation process have been investigated by using n.CeO2, n.ZnO and n.CeO2/n.ZnO (1:1, m:m) nanocatalysts. The process optimization has been performed with the pH, ozone dose, catalyst dose and reaction time parameters. While the optimum conditions have been determined as pH 3, 600 mg/L ozone dose, 10 min reaction time, for all three catalysts, catalyst doses have differed as 50 mg/L for n. CeO2, 30 mg/L for n.ZnO and n.CeO2/n.ZnO. The removal efficiencies of AV 90 have been achieved as 97.04, 96.2 and 95.7% for n.CeO2, n.ZnO and n.CeO2/n.ZnO catalysts, respectively. Kinetic analyses showed that color removal of AV 90 dyestuff followed First order kinetics with R2 values of 0.9987 (n.CeO2), 0.9912 (n.ZnO) and 0.9923 (n.CeO2/n.ZnO) and reaction rate constant values have been calculated as 0,3435 (n.CeO2), 0,3551(n.ZnO) and 0,3226 (n.CeO2/n.ZnO) min−1.