| 摘要 |
1424702 Decolorizing waste aqueous liquid KANEBO Ltd 25 April 1973 [27 April 1972 30 June 1972 14 Feb 1973 19 Feb 1973] 19630/73 Heading C1C [Also in Division C3] Waste coloured aqueous liquid is decolorized by contacting the liquid, which contains at least one non-cationic colouring substance or fluorescent brightening agent, with a coagulating agent containing at least one compound selected from (A) water-soluble condensation products of an aliphatic aldehyde or paraformaldehyde with (a) a compound of formula H 2 N(R 1 -NH-R 2 ) n -NH 2 where R 1 and R 2 are C 1-4 alkylene and n is an integer, a mixture of such a compound and one or more secondary or tertiary amines or a partial deammonization product of such a compound, (b) an aromatic amino compound (including hydrazines) and (c) a mixture of an aliphatic amino compound having at least one guanidino radical and at least one other amino compound selected from compounds of formula ethylene diamine, urea, melamine, ethyleneimine and compounds of formula R 3 -NH-R 4 where R 3 is H or C 1-4 alkyl or alkoxy and R 4 is C 1-4 alkyl or alkoxy; and (B) water soluble metallized complexes of the condensation products (A) with polyvalent metal ions, thereby coagulating the colouring substance or brightening agent and removing the coagulated material from the aqueous liquid. The treatment may be effected at a pH of 6À0 to 8À0 and a conventional coagulating agent selected from aluminium sulphate, polyaluminium chloride, ferric and ferrous chlorides and sulphates and polyacrylamides. A large number of suitable colouring substances are specified. |
