Intelligent treatment of tannery wastewater via H2O2 photocatalytic oxidation coupled adsorption process

Tannery effluents are known for their high levels of organic pollutants and chromium content. In this study, an integrated process comprising advanced oxidation (UV/TiO2/H2O2) and adsorption was developed to decompose the chromium complexes formed with organic substances. In the advanced oxidation process, the H2O2 turned into hydroxyl radicals (OH), which was significantly increased the decompose rate. After 9 h, the COD of the wastewater rapidly decreases to 504 mg/L from 7600 mg/L. However, the COD of the wastewater only decrease to 6535 mg/L from 7600 mg/L without photo-catalyst. The dissociated Cr(III) can be converted into Cr(VI) and adsorbed with the anion exchange resin D296. After the adsorption, the concentration of Cr(VI) was found to be below 0.5 mg/L, achieving a total chromium removal efficiency of 99.5 %. To enhance the process analysis and prediction of real tannery wastewater treatment outcomes, an Artificial Neural Network-Genetic Algorithm (ANN-GA) model was introduced using the Transfer Learning algorithm. The result shows that the maximum error between the predicted values and the actual treated wastewater from the factory was only 0.28 %. The findings obtained from this study provide valuable guidance and strategies for treating complex industrial wastewater.