Supported pervaporation membrane and module containing arrays of

Abstract

A pervaporation membrane comprises a porous, preferably microporous support which is filled from its exterior to its interior surface with a solid, non-removable organophilic polymer which exhibits permselective properties. A support so filled with the polymer and at least 20 .mu.m thick, preferably 50 .mu.m to about 200 .mu.m thick, referred to as a 'thick' film, will preferentially block out water in which a target component is dispersed, yet allow diffusion of the target component. The polymer is forced through the pores of the support, which pores, before they are filled, provided open fluid communication between the opposed interior and exterior surfaces of the support. Preferably, impregnated polymer exudes through and overflows the pores, spreading upon the opposed surfaces of the porous support, and providing opposed coextensive films on either side of the porous support, the films being interconnected by microtendrils of polymer in the pores and channels of the support. A module having microporous hollow fiber membranes is impregnated after the module is constructed. The fibers are through-impregnated with a solution of the polymer and the excess swept away with a sweep gas. In a process for separating plural target components from an aqueous stream, the pervaporation module with 'thick film' pervaporation membranes, will provide a separation factor at least double that of a conventional module with 'thin film' membranes coated upon a microporous support and not filling its pores.