Self-sustained electro-spun polysulfone nano-fibrous membranes and their surface modification by interfacial polymerization for micro- and ultra-filtration

• Polysulfone electro-spun nano-fibrous membranes (PSU ENMs) for micro/ultra-filtration were prepared.
• Effects of electro-spinning parameters and heat post-treatment on the morphology and structure of PSU ENMs.
• Thin-film composite polyester-PSU based ENMs developed by interfacial polymerization technique.
• PSU ENMs are not selective for humic acid solution at pH 3.
• Interfacial polymerization improved the selectivity of the PSU ENMs during the humic acid micro/ultra-filtration tests.

Polysulfone electro-spun nano-fibrous membranes (PSU ENMs) were prepared using a mixture of solvents N,N-dimethyl formamide (DMF) and tetrahydrofurane (THF) for microfiltration and ultrafiltration. The involved electro-spinning parameters, namely, the polymer solution flow rate, the electric voltage and the distance between the needle tip and the collector were varied in the range within which it was possible to obtain bead-free PSU ENMs. Their effects on the morphology and structure of the PSU ENMs were studied. Interfacial polymerization technique was applied to develop novel thin-film composite polyester-PSU based ENMs. The prepared membranes were characterized by means of different techniques such as scanning electron microscopy, contact angle measurements, X-ray diffraction, attenuated total reflectance Fourier transform spectroscopy. Micro/ultra-filtration tests were conducted using humic acid model solutions with a concentration of 15 mg/L at two different pH values (3 and 11). It was observed that PSU ENMs were not selective under acidic conditions, whereas the thin-film composite polyester-PSU based ENMs achieved better separation factors and lower irreversible fouling factors than those of the un-modified PSU ENMs.

SEM images of unmodified (left image) and surface modified (middle and right images) electro-spun nano-fibrous membrane by interfacial polymerization technique.Figure optionsDownload as PowerPoint slide