Fabrication of graphene oxide/polydopamine adsorptive membrane by stepwise in-situ growth for removal of rhodamine B from water

Abstract Polyethersulfone-sulfonated polyethersulfone (PES-SPES) membranes were prepared by non-solvent immersion precipitation method, and then the graphene oxide-polydopamine (GO-PDA)/PES-SPES adsorptive membranes were fabricated by the stepwise in-situ growth method, and employed for the removal of rhodamine B (RhB) from aqueous solutions. The static adsorption thermodynamics, the effects of pH values, adsorption kinetics, and dynamic adsorption/desorption were investigated. The results showed that, the adsorption of RhB on the membrane can be well described by the Langmuir model and the pseudo-second-order kinetic model, and the maximum adsorption capacity of the GO-PDA layer is 87.03 mg g−1, indicating a chemisorption dominated adsorption process. The GO adsorbents and PDA crossslinker contributed to the synergistic adsorption. The adsorptive membranes also exhibited good reusability in dynamic adsorption/desorption cycles.