GB444813A - Improvements in or relating to the bleaching of fatty acids, oils and fats - Google Patents

Abstract

In the bleaching of animal, vegetable, and fish oils, fats, and fatty acids by repeated treatment with aqueous hypchlorite of an alkali or alkaline earth, in each stage the oil or fat is first heated to above its M.P. but not above 212 DEG F., cooled by the addition of the hypochlorite solution or prior thereto as by cooler water, allowed to stand to allow reaction, agitated to complete reaction, settled, preferably heated to above 160 DEG F., and agitated and settled several times, and then reheated for the next addition of hypochlorite. The aqueous liquid may be run off after each hypochlorite treatment or after all hypochlorite has been used; the hypochlorite preferably contains or is mixed with 10 per cent or more of sodium chloride; after any stage or stages the oil or fat may be acidified, e.g. by treatment with sulphuric or hydrochloric acid at 200--212 DEG F.; and the oil may be finally dried at 215 DEG F., or by passing superheated steam through it. Specified fats &c. are coconut, peanut, corn, cottonseed, linseed, sesame, palm, palm kernel, fish and whale oils; tallow; animal greases; fatty acids of the above or of the hydrogenated oils, obtained, e.g. by splitting as described in Specifications 4741/98, 27244/11, 19676/12, 10199/13, and 149,748, [all in Class 91]; stearic, oleic, palmitic, lauric, and linoleic acids, or mixtures thereof; fatty acids obtained by acidifying " foots "; and synthetic fatty acids. Calcium hypochlorite is the preferred bleaching agent; sodium hypochlorite is also specified.