Abstract

The release of dye containing effluent is a great threat to the world today. The purpose of this study is to optimize the removal of Reactive Blue 19 (RB19) dye from aqueous solutions using advanced oxidation process (AOP). Magnesium oxide nanoparticles (MgO NPs) and hydrogen peroxide (H2O2) were used as the catalyst and oxidizer, respectively. Central composite design (CCD) based on response surface methodology (RSM) was applied for optimization of the AOP process. The effects of pH (3-7), molar H2O2/MgO NPs ratio (1-3), initial concentration of RB19 (20-80mg/L), and contact time (30-90min) were investigated on the oxidation process. The CCD was applied to determine the interactive effects of the process parameters and their optimum conditions. One-way analysis of variance (ANOVA) was applied for statistical data analysis. A quadratic model was generated by the CCD to represent the AOP on RB19 degradation. The experimental values obtained for percentage RB19 decolorization were found to be very close to the predicted response values. Based on the design, optimum conditions of pH 3, contact time of 60min, RB19 concentration of 80mg/L and H2O2/MgO NPs molar ratio of 3 were obtained which resulted in 93.77 RB19 removal. High value for the coefficient of determination, R-2 (0.912) and adjusted R-2 (0.805) showed that the removal of RB19 dye using AOP can be described by the RSM. The ANOVA results showed that the quadratic model developed from the RSM was statistically significant for RB19 decolorization. From the study, it could be concluded that the RSM can be a useful tool for optimization and moderation of the process parameters to maximize RB19 dye removal from aqueous solutions and the advanced H2O2/MgO NPs oxidation process.