Substrate modified thin film composite reverse osmosis membrane with improved desalination performance and fouling-resistant characteristics

Thin-film composite polysulfone membranes were fabricated using 0, 0.1, 0.5 and 0.1 wt% modified graphene oxide in the membrane sublayer via the phase inversion method, and were subsequently designated with codes M0, M1, M2, and M3, respectively. The fabricated membranes were employed in the reverse osmosis process for water desalination. The membrane characteristics were examined using Fourier-transform infrared spectroscopy, X-ray crystallography, atomic force microscopy, energy-dispersive X-ray spectroscopy, scanning electron microscopy, and contact angle analysis. The results revealed that the incorporation of 1 wt% modified graphene oxide in the thin film composite membrane led to a 25 % reduction in the contact angle, from 68 degrees to 52 degrees. In the reverse osmosis process, the thin film composite membrane fabricated with 1 wt% modified graphene oxide achieved the highest water flux of 40.05 L/m2.hr and 48.22 L/m2. h for NaCl at 8 and 12 bar pressures, respectively. In addition, the membrane fabricated with 0.5 wt% modified graphene oxide showed the highest salt rejection for Na2SO4 at both 8 bar and 12 bar pressures, with values of 91.69 % and 97.01 %, respectively. This membrane also exhibited a higher antifouling affinity than the plain thin-film composite membrane, with approximately 22.5 % water flux recovery compared to 7.5 % for the plain thin-film composite membrane.