Effects of some Advanced Oxidation Processes and Chlorine on disappearance of Methylene Blue

Disappearance of Methylene Blue (MB) in distilled water has been investigated when it was treated by sunlight and /or chlorine and Fe2+/H2O2 system at different pH values. It is found that the above elements and systems have actions on MB disappearance with different efficiency. The disappearance efficiency by using each system was compared in terms of percentage and kinetics disappearance. By exposing Methylene Blue (MB) aqueous solutions to solar rays, kinetic disappearance increased slowly with decreased pH. This fact, which became faster, is inversed by regarding pH when free chlorine is added to the same aqueous solutions of MB. However, when free chlorine is coupled with sunlight, a remarkable enhancement, at higher pH, of the disappearance activity compared to obtained results with isolated elements.On the other hand, the system H2O2/Fe2+ was also tested to remove MB in terms of kinetic curves at different pH. Important and faster removal levels were obtained at acidic pH.