Selective permeability membranes - of vinyl! sulphonic acid-acrylonitrile! copolymer for fractionation of metal salts

摘要

Metal salts are fractionated by hyperfiltration using a selective permeability membrane made from a 1:17 to 1:5 mol copolymer of vinylsulphonic acid and acrylonitrile. The membranes can be used under strong acid, alkaline, oxidising or reducing conditions, in contrast to prior art membranes, and are suitable for service at pH 1-13 and with phenol-contg. solns. The membranes are easily made, with no complex process stages and are esp. useful for selective purificn. of waste waters from laboratories, factories, plating baths, etc.