Eco-friendly ascorbic acid-integrated graphene oxide composite membranes for high performance ionic and molecular sieving in wastewater treatment

Herein, an eco-friendly GO-based composite membrane was successfully synthesized by integrating with ascorbic acid (AA). The crosslinking/bonding of GO and AA/GO composite membranes were evaluated using FT-IR technology. Surface morphology and cross-sectional investigations of the membranes were investigated by using scanning electron microscopy (SEM). The d-spacing of GO and AA/GO materials was measured using X-ray diffraction (XRD). The as-prepared membranes exhibit excellent permeability and rejection efficiency for numerous dyes and salts. The rejection efficiency and permeability of different dyes were measured as for rhodamine B (rejection 99.9% and permeance 180 +/- 5 L m-2 h-1 bar-1), for methylene blue (rejection 99.7% and permeance 245 +/- 5 L m-2 h-1 bar-1) and rose bengal (rejection 99.4% and permeance 270 +/- 5 L m-2 h-1 bar-1). In addition, the membrane showed good separation for NaCl (rejection 87.5% and permeance 335 +/- 5 L m-2 h-1 bar-1), Ni(NO3)2 (rejection 95.8% and permeance 255 +/- 5 L m-2 h-1 bar-1) and Pb(NO3)2 (rejection 98.9% and permeance 170 +/- 5 L m-2 h-1 bar-1). Furthermore, the as-prepared membranes are most stable in all three media up to 65 days. This approach highlights the potential practical applications of GO-based membranes in treating wastewater effluent from aqueous systems.