Treatment of O3 with Na2S2O8 by ANOVA Interpretation towards Degradation of Azo Dye

Abstract

Advanced oxidation processes (AOPs) especially ozonation method is widely studied in the wastewater treatment field. In this study, it highlighted about three main environmental issues in the world such as 1) proposing a method to overcome uncontrollable effluents from textile industries by using synthetic dyes; 2) creating an improvement of previous conventional method; 3) reduced process time by using statistical approach. To address with this issue, analysis of variance (ANOVA) from Response Surface Methodology (RSM) to study the performance of O3 with the help of persulfate (Na2S2O8) for treating one of azo dyes which is Reactive Green 19. This is due to there is very limited work done by statistical analysis on this study. Hence, ANOVA data would propose statistical models tailored to the data in 2D and 3D contour plots by knowing the three influenced parameters which is pH (6 to 10), persulfate concentration (30 to 70 mM) and contact time (4 to 20 min). Through the analysis, the result can be concluded that improvement of ozonation process with persulfate (Na2S2O8) were statistically significant after all interactive effects gave a positive feedback towards responses. The obtained optimum conditions included a persulfate concentration (49 mM), initial pH (8.89) and contact time (18 min) with fixed initial concentration 100mg/L. The experimental results were corresponded well with predicted models colour removal rates which is 99%.