Abstract
The pervaporation properties of graft copolymer membranes with poly(vinylidene fluoride) (PVF 2), poly(vinyl fluoride) (PVF), poly(hexafluoropropene-co-tetrafluoroethene) (FEP), and polyacrylonitrile (PAN) as trunk materials have been investigated. Various monomers which yield polar, basic, acidic and ionic functional groups have been grafted by means of the preirradiation technique using 160 keV electrons from an accelerator. The purpose was to elucidate the influence of membrane-permeant interactions on the pervaporation of ethanol/water mixtures. Most of the graft membranes exhibit high fluxes of 0.5-3.0 kg-m −2-hr −1 in pervaporation experiments at 343 K with 80% ethanol in the feed solution. Non-ionic membranes exhibit moderate separation factors (α H2O = 2-15) while ionic graft chains lead to very low ethanol concentrations in the permeate, corresponding to α H2O up to 1000. The dependence of pervaporation on the grafting yield, the feed concentration, the temperature and, in the case of ion exchange membranes, the kind of counterion and trunk polymer has been worked out for different grafting systems. The membrane properties have been correlated to the morphology of the grafted films.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call