SORPTIVE AND GAS-SEPARATIONAL PROPERTIES OF PERFLUORINATED ION-EXCHANGE MEMBRANES WITH RESPECT TO WATER-VAPOR

Under equilibrium and dynamic conditions, we have studied the effect o f the type of counterions on the sorptive and gas-separational propert ies of ion-exchange fibrous membranes based on a copolymer of tetraflu oroethylene with 3,5-dioxy-5-methyl-sulfofluoridoctene-1 with respect to water vapor. Membranes are prepared in H+, Na+, Mg2+, CO2+, Cu2+, Z n2+, and Cr3+ forms, and the values of their equilibrium sorptive capa cities, the amounts of the bound and free water, as well as the degree of extraction of water vapor from gas - air mixtures are determined. It is shown that the penetrability of the membranes studied is control led by their sorptive capacity and the radius of the counterion. Intro duction of various cations into the active centers enables us to obtai n membranes with controllable penetrability with respect to water vapo r and makes it possible to create effective desiccants of gases based on modified perfluorinated membranes.