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The electrochemical degradation of ibuprofen (IBP) by electro-Fenton process has been studied in a flow-through system by evaluating the performance of two different iron sources, sacrificial cast iron anode and FeSO4 salt. The effect of operating conditions, including initial IBP concentration, cast iron anode location, initial FeSO4 concentration, applied current, the split current on the iron anode, solution pH, and flow rate on the efficacy of the process was evaluated. The sequence of the electrodes significantly influences ibuprofen removal. When using cast iron anode as iron source, placing the iron anode upstream achieved the best IBP removal rate. Split current of 3 mA applied on the iron anode out of 120 mA total current is the optimum current for remove 1 mg/L of IBP under a flow rate of 3 mL/min. There is a linear correlation between the applied current and the Fe2+ concentration in the FeSO4-system. The initial IBP concentration does not influence the rate of Fenton reaction. Flow rate influences the degradation efficiency as high flow rate dilutes the concentration of OH radicals in the electrolyte. FeSO4-system was less affected by the flow rate compared to the iron anode-system as the concentration of the Fe2+ was steady and not diluted by the flow rate. Both systems prefer acidic operation conditions than neutral and alkaline conditions. Iron-anode can be used as an external Fe2+ supply for the treatment for iron-free. These findings contribute in several ways to our understanding of the electro-Fenton process under flow conditions and provide a basis for how to design the reactor for the water treatment.

Many developing countries, and some developed countries, experience groundwater pollution. This problem is increasing in all areas of the world including Lebanon. Many factors have contributed to the groundwater pollution problem in Lebanon, some unique to the area (e.g., refugees, reliance on private wells) and others similar to those around the world (e.g., climate change, increased use of fertilizers). Efforts are being made to identify the contributing factors and find solutions. This study attempts to determine the nitrate contaminant transport to a contaminated public well in Chadra, Lebanon. MODFLOW software, a U.S. Geological Survey modular finite-difference flow model, is used to model the polluted well with its surrounding pollutant sources. Samples are collected from the well and tested in the laboratory using ASTM standard methods. A 3D model of the well was created and used to study the effect of porosity, time and well abstraction rate on the contaminant's path. Findings showed that the distance is inversely proportional to porosity and proportional to time and abstraction rate. Moreover, the software model results matched testing outcome of the nitrate concentration detected in the subject well.