Textile Wastewater Treatment Using Photonanocatalytic Process (UV/CuO Nanoparticles): Optimization of Experiments by Response Surface Methodology

This study examines the efficiency of photodegradation process (color and COD removal) in textile wastewater treatment, using copper oxide nanoparticles (CuO-NPs) as photocatalyst to propose a suitable alternative for the available approaches. The experiments were developed, using a central composite design and response surface methodology (RSM). RSM was applied to evaluate the effects of different variables, including pH, CuO- NPs concentration, reaction time, and UV light intensity, as well as their interactions for achieving optimal conditions. The second-order model consisted of linear and quadratic terms, which seemed appropriate for color and COD removal. All the variables showed significant effects on color and COD degradation. The optimal conditions for maximum color degradation (83%) included pH of 6.9, contact time of 60 min, CuO- NPs concentration of 0.05 g/L, and UV light intensity of 30 W. In addition, the optimal conditions for maximum COD reduction (99%) were pH of 6.8, contact time of 60 min, CuO-NPs concentration of 0.02 g/L, and UV light intensity of 30 W. Based on the results of this study, CuO-NPs can be used for effective treatment of textile wastewater by high COD and color removal.