Hybrid membrane system with electrochemical oxidation process for removal of Diclofenac sodium from Aqueous Solution

This study presents an innovative approach to eliminating the pharmaceutical pollutant diclofenac sodium (DFS) by combining nanofiltration membrane technology with an electrochemical oxidation process. The nanofiltration membrane was prepared by phase inversion, and modified with cetyltrimethylammonium chloride (CTAC) to improve surface properties and pore structure. The concentrate from the nanofiltration treatment has been utilized as the input feed for the electrochemical section, employing Ti/SnO2-α-Fe2O3 electrodes. The PES/CTAC membrane exhibits a more uniform and stable pore structure, leading to increased permeability and antifouling properties. Additionally, the inclusion of CTAC through the surface adsorption mechanism improved the DFS rejection performance, achieving a maximum rejection rate of 65.2% for the membrane with a composition of 0.1 wt% CTAC. The obtained results show that the titanium electrode coated with SnO2 and α-Fe2O3 nanoparticles removed the DFS pollutant by 56%. In total, both membrane and electrochemical process removed 80.5% of the primary Diclofenac pollutant. According to the low energy consumption of this process (EEC=0.014144 US$/m3) and other results, the combination of the PES/CTAC membrane and Ti/SnO2-α-Fe2O3 electrode is an efficient method for diclofenac sodium pollutant removal.