Treatment of Refinery Wastewater by Chemical Advanced Oxidation Processes (UV-Photolysis, Fenton, and Photo-Fenton): A Comparative Study

This work investigates and compares the effectiveness of chemical advanced oxidation techniques to remediate real refinery wastewater generated from the Al-Samawa refinery plant which has not been treated before by using the present technologies. Real refinery wastewater underwent a batch photo-Fenton oxidation treatment (UV/H۲O۲/Fe۲+) to reduce the oil content. The experiments were designed using a factorial experimental design containing the effects of ۳۰-۹۰ min irradiation time, ۲۵–۲۵۰ ppm hydrogen peroxide, and ۲–۸.۵ pH. A statistical program was used to analyze the results. The optimum values of these variables were ۹۰ min, ۱۰۰ ppm H۲O۲, and pH ۳. The effect of solution temperature on the removal efficiency was studied in the range of ۲۰–۴۰۰ °C. It was found that the temperature notably influences the treatment process, where the highest removal of the organic content of ۹۵.۱۵% was achieved at ۳۰°C. Adsorption equilibrium investigation revealed that the Langmuir model was a more fitted model (R۲ = ۰.۹۹۹۹) for photo-Fenton elimination of oil content than other isotherm models. Consequently, a comparative study of the treatability of UV-photolysis, Fenton, and photo-Fenton processes has been conducted. The core findings of this comparison showed that the oil content removal by using the UV-photolysis process is (۴۹.۲%), the Fenton process (۶۹.۶%, while it shows that the photo-Fenton process is the most effective at getting rid of pollutants (۹۲.۷۵%). As observed the photo-Fenton methods are more effective than other studied methods to treat refinery wastewater.

کلیدواژه ها:

AOPs treatment methods ، Adsorption isotherms ، ANOVA analysis ، Kinetic study