Design and fabrication of polyamine nanofiltration membrane by constituting multifunctional aliphatic linear amine and trifunctional cyanuric chloride for selective organic solvent nanofiltration

Background: Thin film composite nanofiltration (TFC-NF) membranes have been developed for organic solvent nanofiltration. Most of the polyamide TFC-NF membranes are vulnerable to nucleophilic hydrolysis. Methods: A multifucntional amine was crosslinked with a trifucntional non-aqueous monomer namely cyanuric chloride (CC) on surface of self-fabricated polysulfone/polyester terephthalate (PS/PET) membarne support leading to a new polyamine active layer containing TFC-NF membrane named as PA@PS/PET. The fabricated PA@PS/PET membrane was thoroughly characterized by several characterization techniques such as ATR-FTIR, XPS, FE-SEM, Water Contact Angle (WCA), and EDX analysis. Significant Findings: PA@PS/PET TFC-NF membrane showed remakable perfomance in terms of solvent flux for all tested solvents including water, methanol, ethanol and isopropanol. The highest flux was found to be 29.58 L m⁻²h⁻¹ at 8 bar for methanol. The flux of solvents was found to be inversly related to the viscosity of the solvents. The PA@PS/PET membrane showed remarkably high rejection of solute (Congo Red) reaching to a value of ∼98%. Moreover, the PA@PS/PET membrane showed permanant flux of 8.45 L m⁻² h⁻¹ at 2 bar during solute separation (CR dye rejection) tests which hinted the stability of the membrane under the applied operating conditions.