| 摘要 |
Water-insoluble artificial aldehyde resins containing a sulphonic acid group or groups are manufactured by condensing an aromatic compound, containing at least one sulphonic acid group and having a tendency to condense, with an aldehyde or agent yielding it, or by treating an artificial aldehyde resin with a sulphonating agent. In examples: (1) phenol-p-sulphonic acid is condensed with formaldehyde; (2) phenol is sulphonated and the product is condensed with formaldehyde; (3) naphthalene is sulphonated and the product is condensed with formaldehyde; (4) a resin made by condensing m-phenylenediamine with formaldehyde is sulphonated with fuming sulphuric acid.ALSO:Cation exchange is effected in aqueous solutions by passing the solution through a water-insoluble artificial aldehyde resin (i.e. a resin prepared from aromatic compounds and aldehydes) containing a sulphonic acid group or groups, preferably one having a large internal surface and a granular structure. Regeneration may be effected by means of suitable acids or salt solutions. The resins may be prepared by condensing an aromatic compound, containing at least one sulphonic acid group and having a tendency to condense, with an aldehyde or agent yielding it, or by treating an artificial aldehyde resin with a sulphonating agent. In examples: (1) phenol-p-sulphonic acid is condensed with formaldehyde; the product may be used for extracting calcium chloride from solution, and regenerated with acid or common salt solution; (2) phenol is sulphonated and the product condensed with formaldehyde, yielding a product similar in properties to that of (1); (3) naphthalene is sulphonated and the product is condensed with formaldehyde; the product absorbs calcium and copper from solution; (4) a resin made by condensing m-phenylenediamine hydrochloride with formaldehyde is sulphonated with fuming sulphuric acid; the product absorbs copper from a dilute ammoniacal copper solution, e.g. the waste liquor from a copper artificial silk factory. |
