Optimization of electrofenton process in removal of lead and phenanthrene resistant to biodegradation from contaminated soils using response surface method
Subject Areas :
maloos tabatabaee
1
(Department of Environment, West Tehran Branch, Islamic Azad University, Tehran, Iran)
Roya Mafi Gholami
2
(Department of Water and Wastewater Environment, West Tehran Branch, Islamic Azad University, Tehran, Iran)
mehdi borghei
3
(Department of Environmental Processes, Sharif University, Tehran, Iran)
ali esrafily
4
(Department of Environmental Health Engineering, Iran University of Medical Sciences, Tehran, Iran)
Keywords: Optimization, Lead, Phenanthrene, Electrofenton, Removal of contaminants from soil,
Abstract :
This study was performed to use the electrofenton process as an electrochemical oxidation process to remove lead and phenanthrene from soils around the oil refinery in south of Tehran. The reactor used (designed by SolidWorks software) was a discontinuous type with a useful volume of 500 ml and a graphene electrode as a cathode and an iron electrode as an anode (source of divalent iron ion production). The experiment was designed using the response surface methodology (RSM). Variable parameters were pH of the solution (2, 4, 6, 8 and 10), time of the reaction (12.5, 25.0, 37.5, 50.0 and 62.5 minutes), concentration of hydrogen peroxide (0.5, 1.0, 1.5, 2.0 and 2.5 %w/w), and direct electrical current (0.75, 1.50, 2.25, 3.00 and 3.75 A). The highest percentage of lead removal, 85.4%, obtained at pH of 8, H2O2 concentration of 2 %w/w, direct electrical current of 1.5 A, and time of 50 minutes. Also, the highest percentage of phenanthrene removal, 85.95%, obtained at pH of 6, H2O2 concentration of 1.5 %w/w, direct electrical current of 2.25 A, and the time of 37.5 minutes. The obtained results showed that the electrofenton process was able to remove lead and phenanthrene from the soil around the oil refinery.
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