Fabrication of thin film nanocomposite nanofiltration membrane incorporated with cellulose nanocrystals for removal of Cu(II) and Pb(II)

Abstract Thin-film nanocomposite nanofiltration (TFN) membranes were prepared via interfacial polymerization between polyethyleneimine (PEI) and trimesoyl chloride (TMC) with the incorporation of cellulose nanoparticles (CNCs), for the removal of Cu(II) and Pb(II) from aqueous environment. Water contact angle measurements and pure water test showed that the surface hydrophilicity of TFN membranes was improved with the increment of CNCs concentration. Successful deposition of CNCs on the membrane surface was investigated by FTIR analysis. The SEM and AFM results showed that the incorporation of CNCs resulted in a greater surface roughness and a higher surface area to the membranes. The results indicated that the water permeance of TFN membranes increased by 70% compared to a pristine TFC membrane with the CNCs loading mass of 5.5 µg/cm2, and also exhibited the acceptable and competitive removal efficiency for toxic heavy metal ions (CuSO4 98.0%, CuCl2 96.5% and PbCl2 90.8%). To the best of our knowledge, this is the pioneering work to study the combination between CNCs and positively charged thin film composite nanofiltration membranes fabricated by interfacial polymerization of polyethyleneimine (PEI) and trimesoyl chloride (TMC) on polyethersulfone (PES) supporting membrane for the rejection of Cu(II) and Pb(II).