Process for the manufacture of improved fatty acids from low quality fatty oils and fats

摘要

Improved fatty acids are produced from low quality animal and vegetable oils containing unsaturated fatty acids by esterifying the unsaturated acids with an aliphatic alcohol, then polymerizing by heating to say 200-300 DEG C., but not to the boiling-point, if desired while passing through a current of inert gas, with or without reduced pressure, and finally splitting the polymerized substances, after which treatment the free fatty acids are recovered. The esterification is carried out in any usual and convenient manner, for example by refluxing the initial material with three times the theoretical quantity of a monohydric alcohol, preferably in the presence of about 5 per cent by weight of the alcohol of sulphuric acid or like dehydrating agent. If the esterification is carried out with glycerol, it should be used in quantity corresponding to that required for the production of triglycerides, the reaction being carried out at a pressure of 20 millimetres of mercury and at 170-230 DEG C. The initial material may be purified by pretreatment with a dilute mineral acid or a bleaching earth, or by emulsification with water or an agent capable of precipitating mucilaginous matter, such as a solution of acetic acid, phosphoric acid, alum, or trisodium phosphate. Examples of the treatment of acid train oil, train oil fatty acids, and soapstock fatty acids are given. Specifications 262,134, [Class 91, Oils &c.], 306,453, 322,496, [both in Class 2 (iii), Dyes &c.], and 341,390, are referred to.ALSO:Improved fatty acids are produced from low quality animal and vegetable oils containing unsaturated fatty acids by esterifying the unsaturated acids with an aliphatic alcohol, then polymerizing by heating to say 200-300 DEG C., but not to the boiling point, if desired while passing through a current of inert gas, with or without reduced pressure, and finally splitting the polymerized substances, after which treatment the free fatty acids are recovered. The esterification is carried out in any usual and convenient manner, for example by refluxing the initial material with three times the theoretical quantity of a monohydric alcohol, preferably in the presence of about 5 per cent by weight of the alcohol of sulphuric acid or like dehydrating agent. If the esterification is carried out with glycerol, it should be used in quantity corresponding to that required for the production of triglycerides, the reaction being carried out at a pressure of 20 millimetres of mercury and at 170-230 DEG C. The initial material may be purified by pretreatment with a dilute mineral acid or a bleaching earth, or by emulsification with water or an agent capable of precipitating mucilaginous matter, such as a solution of acetic acid, phosphoric acid, alum, or trisodium phosphate. Examples of the treatment of acid train oil, train oil fatty acids and soapstock fatty acids are given. Specifications 262,134, 306,453, 322,496, [all in Class 2 (iii), Dyes &c.], and 341,390, [Group III], are referred to.