Anion-exchange resins and their use in the removal of dissolved oxygen from water

摘要

A method of removing dissolved oxygen from water comprises contacting the water with a quaternary ammonium anion-exchange resin having its functional groups at least partially in the dithionite form, e.g. half in the hydroxide form and the remainder in the dithionite form. The anion-exchange resin may have associated therewith cobalt in the metallic state or in a form reducible to metallic cobalt, whereby oxidation of dithionite occurs without fouling of the resin bed by formation of precipitate (sulfur). A deionizing mixture of anion- and cation-exchange resins also may be present. Ion-exchange resins specified are the polymer of styrene and divinyl benzene which has been (a) chloromethylated and then reacted with t-amine, or (b) sulphonated, and cross-linked acrylic copolymer containing carboxylic groups. Examples give figures illustrating the removal capacity of resins of the invention.ALSO:A quaternary ammonium anion-exchange resin has its functional groups at least partially in the dithionite from, e.g. half in the hydroxide form and the remainder in the dithionite form, and finds application in removing dissolved oxygen from water. The anion-exchange resin may have associated therewith cobalt in the metallic state or in a form reducible to metallic cobalt. A deionizing mixture of anion- and cation-exchange resins also may be present. Specified resins are styrene polymerized and cross-linked with divinyl benzene and then chloromethylated and reacted with t amine, sulphonated cross-linked copolymer of styrene and divinyl benzene, and a cross-linked acrylic copolymer containing carboxylic acid groups.