Patent GB-659775-A (GB)
Title: Production of sulphonated ion exchange resins in stable granular form
IPC: C08F8/34
Filed: 1949-01-25
Abstract: Granular cation exchange resins comprising insoluble sulphonated phenol - formaldehyde resins and sulphonated copolymers of monovinyl aromatic hydrocarbons and polyvinyl aromatic hydrocarbons, which resins contain less than 15 per cent of water and are free from ionizable radicals other than sulphonate radicals, are conditioned so that the granules may be brought into contact with water without extensive shattering by soaking the granules in an aqueous solution containing more than 10 per cent by weight of a dissolved ionizable inorganic compound other than ammonium hydroxide, which compound is incapable of reacting with sulphuric acid to form a water-insoluble sulphate, and maintaining the granules in contact with the solution while diluting it with water until the concentration falls below 10 per cent.  Ionizable compounds specified are phosphoric, sulphuric, hydrochloric, hydrobromic acids, sodium chloride, sulphate or carbonate, potassium chloride, bromide or carbonate, lithium chloride, ammonium chloride or sulphate, magnesium chloride or sulphate, sodium or potassium hydroxide.  The treatment causes the granules to swell.  In examples: (1) a table shows the percentage concentration of NaCl solution by weight in relation to particle mesh size of the granules which prevents spalling of the granules of a resin obtained by condensation of formaldehyde and phenolsulphonic acid; example 2 describes the percentage strength of various acid and salt solutions which do not cause spalling of granules of 10 mesh particle size of a similar resin.  In example(3) a table shows the average size of the granules obtained when treating two batches of resin granules of size 14-16 mesh to 60 mesh, (a) with distilled water, (b) with a 26 per cent NaCl solution diluted by subsequent additions of 100 c.c. portions of water added at intervals of 4 minutes; (5) a resin obtained by sulphonating a copolymer of 75 parts styrene, 8 parts divinyl benzene and 18 parts ethyl vinyl benzene with concentrated sulphuric acid and having granules of 20-30 mesh, was first immersed in a 26 per cent solution of NaCl and then in a 3.5 per cent solution.  On microscopic examination of the granules no shattering was found to have occurred.ALSO:Granular cation exchange resins comprising insoluble sulphonated phenol-formaldehyde resins and sulphonated copolymers of monvinyl aromatic hydrocarbons and polyvinyl aromatic hydrocarbons which resins contain less than 14 per cent water and are free from ionizable radicals other than sulphonate radicals, are conditioned so that the granules may be brought into contact with water without extensive shattering by soaking the granules in an aqueous solution containing more than 18 per cent by weight of a dissolved ionizable inorganic compound other than ammonium hydroxide, which compound is incapable of reacting with sulphuric acid to form a water insoluble sulphate, and maintaining the granules in contact with the solution while diluting it with water until the concentration falls below 10 per cent.  Ionizable compounds specified are phosphoric, sulphuric, hydrochloric, hydrobromic acids, sodium chloride, sulphate or carbonate, potassium chloride bromide or carbonate, lithium chloride, ammonium chloride or sulphate, magnesium chloride or sulphate sodium or potassium hydroxide.  The treatment causes the granules to swell.  In example 1 a table shows the percentage concentration of NaC1 solution by weight in relation to particle mesh size of the granules which prevents spalling of the granules of a resin obtained by condensation of formaldehyde and phenolsulphonic acid.  Example 2 describes the percentage strength of various acid and salt solutions which do not cause spalling of granules of 10 mesh particle size of a similar resin.  In example 3 a table shows the average size of the granules obtained when treating two batches of a resin granules of size 14-16 mesh to 60 mesh (a) with distilled water (b) with a 26 per cent NaC1 solution diluted by subseuent additions of 100 cc. portions of water added at intervals of 4 mins.  (5) A resin obtained by sulphonating a copolymer of 75 pts. styrene, 8 pts divinyl benzene and 18 pts. ethyl vinyl benzene with concentrated sulphuric acid and having granules of 20-30 mesh was first immersed in a 26 per cent solution of NaC1 and then in a 3.5 per cent solution.  On microscopic examination of the granules no shattering was found to have occurred.