Preparation of pure palmitic acid and a by‐product plasticizer from cottonseed oil

Summary A laboratory process has been developed which permits the isolation of a highly purified palmitic acid from cottonseed acids through the recrystallization of its cyclohexylamine salt from acetone and subsequent regeneration of the acid. The by‐product, predominantly cyclohexylamine salts of the unsaturated fatty acids, can be modified and converted to morpholides which have shown promise as vinyl plasticizers. The morpholine salts can be obtained as a direct byproduct by the use of an appropriate mixture of cyclohexylamine and morpholine with the composite acid. By using an amount of cyclohexylamine closely equivalent to the saturated fatty acid content and sufficient morpholine to make up the residual neutralization equivalent of the composite cottonseed acids, the saturated acids can be isolated as cyclohexylamine salts. The stripped mother liquor will consist essentially of the morpholine salts of the unsaturated acids. Pure palmitic acid is obtained by recrystallization of the cyclohexylamine salts. The complete process is applicable to fatty acids from other natural glyceridic oils in which the dominant saturated acid bears a ratio to the other saturated acids closely paralleling that in cottonseed oil. The process is not operable with partially hydrogenated oils.