Patent GB-779178-A (GB)
Title: Ion exchange resins and method of preparation thereof
IPC: B01J47/00
Filed: 1955-06-16
Abstract: The aqueous content of synthetic resins having ion exchange properties can be reduced to 14-40 per cent without causing spalling and floating of the resin granules when mixed with water by wetting the granules with an aqueous solution of a surface exchange agent and then dehydrating the wetted resin.  Ion exchange resins specified are (1) polymer resins-crosslinked resinous copolymers of monovinyl aromatic compounds and polyvinyl compounds, e.g. sulphonated or quaternized copolymers of styrene, vinyl-toluene-xylene, -naphthalenechlorobenzene with divinyl-benzene, -toluene, -xylene, -naphthalene and copolymers of methacrylic acid and poly-unsaturated compounds.  (2) Condensation resins-phenol-formaldehyde resins and sulphonated products of such resins and sulphonated products of such resins, aminoplast resins, polyamine-epichlorhydrin resins.  The surface active agents used are watersoluble or used in solution, e.g. in alcohols or ketones; anionic, cationic or non-ionic surface active agents may be used preferably in conjunction with resins having opposed characteristics so that they are not strongly absorbed by the resins.  In examples: (1) a sulphonated styrene-divinyl benzene copolymer having a moisture content of 51 is a 6.5 per cent aqueous solution of sodium alkyl aryl sulphonates derived from petroleum base hydrocarbons and agitated for half an hour; the solution was drained off and the resin granules dried in a rotary drier to a moisture content of 20-25 per cent; when poured on to tap water 100 per cent of the resin particles sank in 5 minutes.  (2) An anion exchange resin having quaternary ammonium groups attached through methylene bridges to a cross-linked divinyl benzene copolymer was wetted with an alkyl phenyl polyoxyethylene ether and then dried to a moisture content of 12 per cent.  (3) A weakly basic cation exchange resin having carboxylic groups attached to a base resin prepared by copolymerization of methacrylic acid and an unsaturated compound and having a moisture content of 55 per cent was wetted with sodium dioctyl sulfosuccinate and dried at 80 DEG  C. to a moisture content of 21 per cent.ALSO:The aqueous content of ion-exchange synthetic resins is reduced to 14-40 per cent without causing spalling or floating of the resin granules when mixed with water by wetting the granules with an aqueous solution of a soluble surface active agent and then dehydrating the wetted granules.  Ion-exchange resins specified are (1) polymer resins: cross-linked resinous copolymers of monovinyl aromatic compounds and polyvinyl compounds e.g. copolymers of styrene, vinyl-toluene, -xylene, -naphthalene, -chlorbenzene with divinyl -benzene, -toluene, -xylene &c., and sulphonated products of such resins; quaternary ammonium anion-exchangers and copolymers of methacrylic acid with unsaturated compounds may also be used; (2) condensation resins: phenol-formadehyde resins and their sulphonated products, aminoplast resins, polyamine aldehyde-ketone resins, polyamine-epichlorhydrin resins.  The surface active agents are water-soluble or used in solution in alcohols or ketones; anionic, cationic, or non-ionic types may be used, preferably in conjunction with resins having opposed characteristics.  In examples (1) a sulphonated polystyrene resin having a moisture content of 51 per cent is mixed with a 0,5 per cent aqueous solution of sodium alkyl aryl sulphonates derived from petroleum base hydrocarbons; the mixture is agitated for half an hour, the solution drained off and the granules dried on a rotary drier to a moisture content of 20-25 per cent.  When poured on to tap water 100 per cent of the granules sink in 5 mins.