Chitosan-wrapped multi-walled carbon nanotubes (CS/MWCNT) as nanofillers incorporated into nanofiltration (NF) membranes aiming at remarkable water purification

Green process engineering, following the principles of the process intensification strategy, may make a significant contribution to industrial sustainability. Membrane-based separation and its potential have lately gained widespread recognition as assisting in the pursuit of these principles. Consequently, while focusing on a novel eco-friendly, cost-effective approach, we investigated the synergistic effect of incorporating multi-walled carbon nanotubes (MWCNTs) into the carbohydrate polymer chitosan (CS) on the nanofiltration performance of the mixed matrix polyethersulfone (PES) membranes to obtain highly decolorized water from licorice root extraction wastewater (LREW). To this end, following the optimization of pristine PES membranes in terms of their polymer concentrations and thicknesses, CS/MWCNT nanoparticles (0, 0.1, 0.5, and 1.0 wt%) were incorporated into the optimized matrix of pristine PES. Along with the physicochemical properties studied, water contact angle, pure water flux (PWF), color and COD removal, and antifouling properties were evaluated, with the 0.5 wt% CS/ MWCNT achieving the highest permeate flux (similar to 9.41 kg/m(2).h) and color removal (similar to 93 %). Ultimately, the longterm flux decline and color removal of the optimum membrane were evaluated using three different wastewater sources, shedding light on its promising future.