A study of performance enhanced and fouling resistant functionalised multiwalled carbon nanotube embedded polysulfone nanocomposite membranes for efficient removal of proteins, polysaccharides, humic acid, and E. Coli

Performance-enhanced and fouling-resistant nanocomposite ultrafiltration membranes were made by employing multiwalled carbon nanotube (MWCNT), and carboxylated MWCNT (cMWCNT) as nanofillers in a polysulfone (PSf) polymer matrix. The membranes were characterised for hydrophilicity, tensile strength, microstructure and surface roughness. The performance was tested by evaluating rejection of a single uncharged solutes i.e, polyethylene oxide (PEO) of molecular weight 100 kDa. During PEO rejection study, flux increase was found 22% in PSf-MWCNT, and 38% in PSf-cMWCNT, against PSf membrane without compromising solute rejection properties. Filtration experiments employing bovine serum albumin (BSA), sodium humate (Na-HA), sodium alginate (Na-alginate), and Escherichia coli ( E. coli ) were performed to evaluate the separation efficiency and anti-fouling capabilities of the membranes. At a concentration of 0.5 wt%, cMWCNT based nanocomposite membrane showed the highest increase in product permeability and the minimum decrease in product flux resulting from exposure to E. coli , BSA, and HA feed solution, making cMWCNT the most suitable nanoparticle for performance enhancement and fouling resistance. These MWCNT based high-performance fouling resistant membranes show excellent promise for commercial exploitation as UF membranes for water treatment applications.