Authors
Abstract
Hollow fiber ultrafiltration (UF) membranes were prepared using Polyethersulfone
(PES), alcohol (n-Propanol) as additive and N, N-dimethylacetamide (DMAc) as a
solvent. Asymmetric hollow fiber UF membranes were spun by wet phase
inversion method from 17 wt% solids of PES/additive/NMP solutions. The alcohol
additive was n-Propanol while the external coagulant was water. Effects of n-
Propanol concentrations in the dope solution on morphology and separation
performance of PES hollow fiber UF membranes were investigated. UF
membranes were characterized in terms of scanning electron microscope (SEM)
while UF experiments were conducted using polyethylene glycol (PEG20,000MW)
and poly (vinyl pyrrolidone) (PVP 40,000MW), as a solute. It was found that the PES
UF membrane morphology changed from long two finger-like structure through a
short two finger-like structure to the two void-like structure as n-propanol
concentration in the dope solution increased from 5 to 20 wt % using water as a
bore fluid; pure water permeation fluxes (PWP) increased from 47 to 201
L/m2.h.bar while rejections of PEG MW20,000 and PVP MW40,000 for wet-spun
PES hollow fiber membranes were decreased with increased of n-propanol
concentration up to 20%. Using above method, PES hollow fiber UF membrane
with high pure water permeation flux could be prepared while the molecular
weight cut-off of PES hollow fiber membranes is approximately 20,000.
Keywords
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