Preparation And Characterization Of PVC Hollow Flber Membrane

This paper mainly studied the preparation of charged PVC/PFSA hollow fibermembrane, the preparation of PVC/TEOS hollow fiber membrane, the preparation ofPVC/P (VAc-Co-VP) hollow ifber membrane and their basic properties.Recoveryof perfluorosulfonic acid resin (PFSA) were conducted by regeneration and dissolu?tion of the derteriorated perfluoro-ion-exchange membrane (PFIEM) in chlor-alkaliindustry. Moreover, the recovered PFSA was reused to preparare hollow fiber ultrafil?tration membranes.First of all, the charged polyvinyl chloride(PVC) hollow fiber ultrafiltrationmembranes were prepared with PFSA as additive by wet-spinning method. Evolutionof the precipitation kinetics, morphologies, permeation performances, size anddistribution of aperture, dynamic contact angle of membrane surface,elecrokineticsand mechanical properties of charged PVC/PFSA hollow fiber membrane wereinvestigated with the PFSA content and bore liquid. The results illustrate thatP V C/PF S A/DM Ac dopes experience an instantaneous and delayed demixingmechanism and the precipitation rate increases with the addition of PFSA. The purewater flux of the membrane increases with the increase of content of PFSA, but whenPFSA content is5%, the pure water lfux declines. Average pore diameter size andMWCO of membrane changes as the pure water lfux of the membrane changes.Membrane surface zeta potential ‘，charge density a increases as the content of PFSAincreases, isoelectric point values gradually decline. The dynamic contact angle ofmembrane surface changes over time,and along with the increase of the content ofPFSA, changes more obviously. The mechanical properties of PVC/PFSA membranesalso increase when the PFSA content increases.Moreover, PVC hollow fiber membranes were prepared with TEOS as additive by wet-spinning method. Results indicate that PVC/TEOS/DMAc dopes experience aninstantaneous and delayed demixing mechanism and the precipitation rate increaseswith the addition of PFSA. The dynamic contact angle of membrane surface changesover time, and changes more obviously as the content of PFSA increases. Membranebreaking strength, breaking elongation were gradually increasing by the increase ofTEOS content. Membranes are contaminated by bovine serum albumin(BSA) andregenerated.Recovery rate increases as the water lfux increases, pollution-resistant ofthe membrane also strengthens.Finally, this paper studied the preparation and performances of PVC/P (VAc-Co-VP) hollow ifber membrane by wet spinning method.It turns out that the precipitationrate increases with the addition of P(VAc-Co-VP). The pure water flux of themembrane increases with the increase of content of P(VAc-Co-VP). The mechanicalproperties of PVC/P(VAc-Co-VP) membranes also increase when the P(VAc-Co-VP)content increases. Membrane breaking strength, breaking elongation were graduallyincreasing by the additive of P(VAc-Co-VP). Membranes were fouled by bovineserum albumin(BSA) and regenerated, and recovery rate increases as the water fluxincreases, pollution-resistant of the membrane also strengthens.