GB958438A - Removal of organic anionic synthetic detergents from waste water - Google Patents

Abstract

Synthetic, organic, anionic detergents, such as sodium dodecyl benzene sulfonate and sodium lauryl sulfate are removed from waste waters by contacting said waste water with a solution of an amine containing at least 20 carbon atoms and having at least one fatty chain of 6-22 carbon atoms in a water-immiscible, organic solvent to form a complex of the detergent and the amine in the organic phase; separating the two phases; discharging the treated water; contacting the immiscible-organic phase containing the complex with an aqueous, stripping-solution to break the complex and extracting the detergent material into the aqueous, stripping-solution; separating the stripped, immiscible-organic phase containing the amine from the aqueous stripping-solution and recycling the same for further treatment of waste waters. Amines used are tricaprylylamine, primary tallow amine, secondary hydrogenated tallow amine the acetate of primary tallow amine b -hydroxy dodecyl dinonyl amine and 9(10) dodecylamino-10(9)-hydroxystearonitrile. Examples of organic solvents are benzene, kerosene, furfural chloroform, 2-ethyl hexanol iso-octane and petroleum naphtha. Examples of stripping solutions are sodium hydroxide, calcium hydroxide, barium hydroxide, soda lime, ammonium hydroxide preferably buffered with ammonium chloride sodium carbonate, di-sodium hydrogen phosphate sodium biphosphate, ammonium acetate, sodium bicarbonate, sodium chloride, methylamine, sodium perchlorate, calcium chloride, sulphuric acid, sodium hydroxide, citric acid, sodium hydroxide, phosphoric acid, ammonium acetate and calcium chloride. Emulsions present during stripping may be effectively countered by the addition of small amounts of additives such as isopropyl alcohol and normal deceyl alcohol. In some operations the aqueous solution of anionic material is desirably acidified before extraction to a pH desirably below about 6.ALSO:Synthetic, organic, anionic detergents, such as sodium dodecyl benzene sulfonate and sodium lauryl sulfate are removed from waste waters by contacting said waste water with a solution of an amine containing at least 20 carbon atoms and having at least one fatty chain of 6-22 carbon atoms in a water-immiscible, organic solvent to form a complex of the detergent and the amine in the organic phase; separating the two phases; discharging the treated water; contacting the immiscible-organic phase containing the complex with an aqueous, stripping-solution to break the complex and extract the detergent material into the aqueous stripping-solution; separating the stripped, immiscible-organic phase containing the amine from the aqueous stripping-solution and recycling the same for further treatment of waste waters. Amines used are tricaprylylamine, primary tallow amine, secondary hydrogenated tallow amine, the acetate of primary tallow amine, b -hydroxy dodecyl dinonyl amine and 9(10) dodecylamino-10(9)-hydroxystearonitrile. Examples of organic solvents are benzene, kerosene, furfural chloroform, 2-ethyl hexanol isooctane and petroleum naphtha. Examples of stripping solutions are sodium hydroxide, calcium hydroxide, barium hydroxide, soda lime, ammonium hydroxide preferably buffered with ammonium chloride, sodium carbonate, di-sodium hydrogen phosphate, sodium biphosphate, ammonium acetate, sodium bicarbonate, sodium chloride, methylamine, sodium perchlorate, calcium chloride, sulphuric acid, sodium hydroxide, citric acid, sodium hydroxide, phosphoric acid, ammonium acetate and calcium chloride. Emulsions present during stripping may be effectively countered by the addition of small amounts of additives such as isopropyl alcohol and normal deceyl alcohol. In some operations the aqueous solution of anionic material is desirably acidified before extraction to a pH desirably below about 6.