Fatty acids linseed, distilled

The raw materials for the manufacture of soap, the alkali salts of saturated and unsaturated C10-C20 carboxylic acids, are natural fats and fatty oils, especially tallow oil and other animal fats (lard), coconut oil, palm kernel oil, peanut oil, and even olive oil. In addition, the tall oil fatty acids, which are obtained in the kraft pulping process, are used for soap production. A typical formulation of fats for the manufacture of soap contains 80-90% tallow oil and 10-20% coconut oil [2]. For the manufacture of soft soaps, the potassium salts of fatty acids are used, as are linseed oil, soybean oil, and cottonseed oil acids. High-quality soap can only be produced by high-quality fats, independent of the soap being produced by saponification of the natural fat with caustic soda solution or by neutralization of distilled fatty acids, obtained by hydrolysis of fats, with soda or caustic soda solutions. Fatty acids produced by paraffin wax oxidation are of inferior quality due to a high content of unwanted byproducts. Therefore in industrially developed countries these fatty acids are not used for the manufacture of soap. This now seems to be true as well for the developing countries. 

The yield is based on a linseed oil containing approximately 45 per cent of linolenic acid. Because of the formation of stereoisomers, only 25 per cent of the bromoacid is precipitated in the solid form. By using water-white distilled linseed fatty acids, obtained from Archer-Daniels-Midland Company, Minneapolis, Minnesota, the yield of solid bromoacid may be increased to 48-53 g. 

The ether layer is washed successively with 5% hydrochloric acid, 5% sodium carbonate aqueous solution and water, and then dried over sodium sulfate. Upon evaporation of ether, the residue is subjected to fractional distillation in vacuo, thereby to yield 8.9 g. of N-methyl linseed oil fatty acid amide, B.P. 178-190° C./0.03 mm. Hg, I.R. 1,650 cm.-l. (I.R. means wave number of the infrared absorption spectrum.)... 

Upon evaporation of ethyl ether, the residue is subjected to careful fractional distillation, thereby to yield 18.2 g. of N-cyclohexyl linseed oil fatty acid amide, B.P. 195-208° C./0.03 mm. Hg. 

F. is applied to distilled fatty acid mixtures of coconut or - pahn kernel oil (Ce-Cig) and separate unsaturated fatty acids from - rape-seed (C18-C22) oil, as well as for the separation of tall oil fatty acids. The fractionation of tallow, soybean, cottonseed and linseed fatty acids is practiced only in rare cases. High degrees of purity (up to 99%) are reached. F. is carried out in vacuum columns that are filled with internal packings and/ or trays. These necessary devices cause a pressure increase (vacuum loss) which has to be compen-... 

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