Chitosan-wrapped multiwalled carbon nanotube as filler within PEBA thin film nanocomposite (TFN) membrane to improve dye removal

Herein, a thin film nanocomposite (TFN) membrane was prepared through deposition of a very thin mixed matrix layer of PEBAX®1657/chitosan-wrapped multiwalled carbon nanotubes (CWNTs) on an ultraporous polyethersulfone (PES) substrate. The eco-friendly CWNTs were synthesized via non-covalent functionalization of MWNTs by carbohydrate polymer chitosan. They were then incorporated into PEBAX®1657 matrix at different loadings (0, 0.1, 0.5, 1 and 2 wt%). The membranes were analyzed using SEM, AFM, FTIR, XRD and contact angel analyses. Furthermore, pure water fluxes through the membranes were investigated at 1, 2 and 3 bar and Malachite green separation properties of the membranes were evaluated at 2 bar. The results showed that the highest permeate flux (∼13.85 L/m2h) and rejection (∼98.7%) were obtained at 1 wt% and 0.1 wt% CWNT dosages, respectively. Additionally, the slight flux decline of the membranes during 5 h indicated the improved antifouling properties.