Characterisation of Romakon (TM)-PM pervaporation membranes for the separation of dilute aqueous alcohol mixtures

摘要

Thin-film composite pervaporation membranes with selective layer from pyromellitic dianhydride -4,4' oxydianiline polyimide on porous poly(amide-imide) support (Romakon (TM)'-PM) for treatment of water/ethanol mixtures with exceeding water content (> 50 wt% water) are characterised by the use of scanning electron microscopy, atomic force microscopy and X-ray diffraction. Membranes showed high values of flux, separation factor and PSI (up to 774) in the selected feed mixture composition range. The influence of the support and structural features of the polyimide in the coating layer on the transport properties is discussed. The membranes are successfully tested in terms of pervaporation dehydration of beer. The influence of the permeate temperature on the separation process performance is discussed.