Performance evaluation of amino-functionalized mesoporous/PES nanofiltration membrane in anionic dye removal from aqueous solutions

In this study, the FSM-16 and FSM-16 modified by metformin (FSM-16-met) additives were applied as modifiers for polyethersulfone-based membranes. The modified membranes were evaluated in terms of morphology, surface roughness, hydrophilicity, pure water flux, pore size and porosity, and resistance ability. The obtained experimental data indicated promising enhancement in permeated flux and hydrophilicity after introducing the FSM-16-met nanomaterials into the membrane texture. In the case assessment of the fabricated membranes, dye removal capability was performed using the direct red-16 and methyl orange (30 mg/L). The modified membranes showed significantly higher dye rejection ability (> 97% for direct red-16 and 95% for methyl orange) compared to the bare membrane (76% for direct red-16 and 74% for methyl orange). The antifouling evaluations were run for milk powder (1000 mg/L) filtration and the best performance was obtained for the modified membrane with 0.1wt.% FSM-16-met (FRR = 95.55 ± 1.91%, Rir = 4.45 ± 0.089%). Also, the effect of the feed pH and concentration, temperature, and membrane driving force was considered on the membrane behavior. High stability in long-term performance was also observed for the modified membrane after 25 h re-running.