METHOD FOR PURIFYING WASTE WATERS WHICH CONTAIN ANIONIC-TYPE ORGANIC COMPOUNDS

1520815 Treating water to remove anionic organic compounds ANIC SpA 30 Jan 1976 [3 Feb 1975] 03872/76 Heading C1C Impure water containing an anionic organic compound is purified by mixing the impure water with an organic compound containing two or three triarylphosphonium groups and separating the resulting insoluble product of the reaction between the triarylphosphonium compound and the anionic organic impurity. The triarylphosphonium compound is preferably a compound of the formula Ar 3 P+-A-P+Ar 3 .2 X- (I) where Ar is an optionally substituted phenyl or α- or #-naphthyl group, X- is an anion of an inorganic or organic acid and A is a divalent organic radical derived from an aliphatic, aromatic or araliphatic hydrocarbon or a radical or the Formula (i) -(CH 2 ) n -CONH-B-NHCO-(CH 2 ) n - where n is 1 to 4 and B is a divalent radical derived from an aliphatic, aromatic or araliphatic hydrocarbon, (ii) -(CH 2 ) n -OCONH-B-NHCOO-(CH 2 ) n - where n is 2 to 6, (iii) -(CH 2 ) n -OCO-B-COO-(CH 2 ) n - where n is 2 to 6, and (iv) -(CH 2 ) n -COO-B-OCO-(CH 2 ) n - where n is I to 6. The present process may be used to remove dyes containing sulphone groups from residual dyeing baths and to purify water containing anionic surfactant.