Enhanced anion exchange membranes for efficient chlorine removal via polypyrrole, polyethyleneimine, and graphene oxide Co-deposition

Anion exchange membranes polypyrrole-modified(PPy-M), polypyrrole-graphene oxide-modified(PPy-GO-M), and polypyrrole-polyethyleneimine-graphene oxide-modified(PPy-PEI-GO-M) were synthesized using in situ polymerization for advanced desulfurization wastewater treatment and cathodic scaling inhibition in membrane electrolysis(ME). Characterization by SEM-EDX(scanning electron microscope-energy-dispersive X-ray spectroscopy), AFM(Atomic force microscopy), FT-IR(Fourier-transform micro-infrared spectrometer), XPS(X-ray photoelectron spectroscopy), and Raman spectroscopy revealed the membranes morphology and chemical properties, and their basic performances, including ion exchange capacity, water uptake, contact angle, zeta potential,perm-selectivity, and the membrane resistance, were rough analyzed. PPy-PEI-GO-M showed the best performance, with an ion exchange capacity of 2.57 mmol g -1 , contact angle of 85°, zeta potential of +15.59mV, membrane resistance of 6.97 Ω cm 2 , and perm-selectivity of 98%. Under optimal electrolysis conditions (ME time 180 min, temperature 30°C, current density 40 mA cm -2 , electrode spacing 4 cm), it achieved a Cl - removal rate of 96.83% without cathodic scaling, with treated effluent successfully reused in a flue gas desulfurization system. This modified membrane shows strong potential for water treatment applications.