Method of treatment of wool scouring or other liquors containing grease and soap or the like for the recovery and if required for the purification of technically-valuable products therefrom and the re-use of the liquors

摘要

508,371. Treating wool washing liquors. JONES, G., and McGREGOR & SONS, Ltd., J. W. Nov. 29, 1937, No. 32949. Drawings to Specification. [Class 91] Wool-washing liquor is freed from soap and grease by adding the oxide, hydroxide, or the normal or basic salt of a metal which (a) forms water-insoluble soaps, (b) forms insoluble normal or basic salts with a polybasic acid, (c) forms water-soluble acid salts with a polybasic acid, then treating the mixture with a polybasic acid in sufficient amount to form the corresponding acid salt of the added oxide and of the alkali carbonates present in the liquor, whereupon the soaps and grease are precipitated and separated. Alternatively, the acid salt is added directly. For example, the liquor is treated with chalk or milk of lime, and then carbon dioxide or dust-free flue gas is blown in, while keeping the temperature low. Precipitation is assisted by adding fuller's earth, bentonite, aluminium sulphate, magnesium or calcium chloride or sulphate, or ferrous sulphate. The liquor is then filtered warm, and the filtrate freed from calcium bicarbonate by boiling, blowing in air at 160‹ F., or addition of caustic alkali; the precipitate is removed by filtration, leaving the regenerated liquor. The moist soap and grease obtained at the first separation stage is worked up (1) by extracting with boiling benzene or toluene which removes the grease and water ; (2) the soap residue is rejected or used as precipitating agent at the first stage, and the grease containing some soaps purified by neutralizing and extracting with acetone and ethyl or methyl acetate, if desired in the presence of an adsorbent ; (3) by treating the soap residue to form fatty acids which may be connected into alkali soaps, and used for wool scouring.