Graphene oxide based mixed matrix membrane in the presence of eco-friendly natural additive gum Arabic

Abstract

The hydrophobic property of polymeric membrane is one of the major issues in water treatment application as it leads to a lower membrane efficiency and performance during separation process. Hence, a mixed-matrix membrane (MMM) that incorporates polymeric substance, natural additive and nanomaterial could be adopted to resolve this issue. This study portrays the preparation of a hydrophilic graphene oxide-based MMM by employing polysulfone (PSf) polymer, graphene oxide (GO) nanomaterial and eco-friendly natural additive gum Arabic (GA). The membranes were prepared via phase inversion by varying the concentration of GO (0.2, 0.6 and 1.0 wt%) at constant amount of GA and PSf at 1.5 wt% and 18 wt%, respectively. These fabricated membranes underwent several characterization tests in terms of surface hydrophilicity, pore size, porosity measurement and field emission scanning electron microscopy (FESEM). The characterization analysis indicated that MMM fabricated with 0.6 wt% of GO possessed highest porosity, largest mean pore size, and improved hydrophilicity due to the presence of oxygen containing functional groups associated with GO and GA. This contributed to the highest water flux result at an average of 63.55 L/m2·h at 4 bar operating pressure. At the same time, it also exhibited a considerably good rejection property and stronger antifouling property with humic acid rejection rate of 95% and flux recovery ratio of 88%, respectively. The finding showed that the incorporation of GO and GA could attain synergy benefits in improving the membrane properties and performance.