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

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.

Automated summary

The GO-PDA adsorptive membranes showed efficient removal of RhB from aqueous solutions, with synergistic adsorption effects between GO adsorbents and PDA crosslinker. The adsorption process can be described by Langmuir and pseudo-second-order kinetic models, highlighting a chemisorption dominated process. The membranes also exhibited good reusability in dynamic adsorption/desorption cycles.