Patent GB-743166-A (GB)
Title: Process for the separation of carboxylic acid ester mixtures
IPC: C07C67/48
Filed: 1953-11-18
Abstract: Carboxylic acid ester mixtures are separated into components of different melting points by mixing a mixture of liquid and solid esters with an aqueous solution containing a surface-active substance and isolating the liquid and solid esters separated thereby.  Liquid organic compounds may be further added to the mixtures.  The aqueous solution containing the surface-active substance may also contain electrolytes, colloidal substances, water-soluble organic liquids, and substances which lower the freezing point.  Specified esters include glycerides, wax esters, isomeric phthalic acid esters and esters of phenoxy acetic acid with sperm oil alcohol.  The surface-active substances may comprise anionic compounds such as alkyl benzene sulphonates and alkyl sulphonates, sulphated alcohols, sulphonated fatty acid monoglycerides and soaps, particularly ethanolamine soaps. Compounds specified comprise sodium and magnesium salts of sulphated alcohols of chain length C12 to C14, C12 to C18 and C10, and soap with mono- and diglycerides.  Cationic compounds may be used and a specified compound is dodecyl-benzyl-diethyl ammonium chloride.  Other compounds may comprise polyglycol ethers of fatty alcohols or alkyl phenols, polyglycol esters of fatty acids, partial ethers of higher alcohols and partial esters of fatty acids with polyvalent alcohols.  The further liquid organic compound which may be added to the mixtures comprise organic solvents and the liquid esters accumulating during the process.  The electrolytes added to the aqueous solution containing the surface-active substance may comprise sodium sulphate or chloride, magnesium salts, and nickel chloride.  The colloidal substances added thereto may comprise glue, gelatine, tragacanth, pectines, alginates, polyacrylates, cellulose glycollates and methyl celluloses.  Substances lowering the freezing point may comprise polyvalent alcohols and their derivatives such as ethylene glycol, glycerine, polyglycerine and polyglycols and the partial ethers thereof.  The esters to be separated are shaken or stirred with the aqueous solution, and the liquid and solid esters are separated by standing, the liquid esters being at the top and the solid esters being in the aqueous phase thereunder, or by centrifuging, preferably continuously in solid jacket centrifuges.  A second separation may be made in either the liquid or solid ester using a fresh aqueous solution of the surface-active substance.  The aqueous solution may be separated and used again.ALSO:Fats and waxes are separated into components of different melting points by mixing a mixture of liquid and solid fats or waxes with an aqueous solution containing a surface-active substance and isolating the liquid and solid fats or waxes separated thereby.  Liquid organic compounds may be further added to the mixtures.  The aqueous solution containing the surface-active substance may also contain electrolytes, colloidal substances, water-soluble organic liquids, and substances which lower the freezing point.  The starting materials exemplified comprise lard, sperm oil, olive oil, cocoa butter, hardened coconut fat, and palm oil.  The surface-active substances may comprise anionic compounds such as alkyl benzene sulphonates and alkyl sulphonates, sulphated alcohols, sulphonated fatty acid monoglycerides and soaps particularly ethanolamine soaps. Compounds specified comprise sodium and magnesium salts of sulphated alcohols of chain length C12 to C14, C12 to C18 and C10, and soap with fatty acid mono- and diglycerides. Cationic compounds may be used, and a specified compound is dodecyl-benzyl-diethyl ammonium chloride. Other compounds may comprise polyglycol ethers of fatty alcohols or alkyl phenols, polyglycol esters of fatty acids, partial ethers of higher alcohols, and partial esters of fatty acids with polyvalent alcohols.  The further liquid organic compounds which may be added to the mixtures comprise organic solvents and the liquid esters accumulating during the process.  The electrolytes added to the aqueous solution containing the surface active substance may comprise sodium sulphate or chloride, magnesium salts, and nickel chloride.  The colloidal substances added thereto may comprise glue, gelatine, tragacanth, pectines, alginates, polyacrylates, cellulose glycolates and methyl celluloses.  Substances lowering the freezing point may comprise polyvalent alcohols and their derivatives such as ethylene glycol glycerine, polyglycerine, and polyglycols and the partial ethers thereof.  The fats or waxes to be separated are shaken or stirred with the aqueous solution and the liquid and solid esters are separated by standing, the liquid esters being at the top and the solid esters being in the aqueous phase thereunder, or by centrifuging, preferably continuously in solid jacket centrifuges.  A second separation may be made on either the liquid or solid ester using a fresh aqueous solution of the surface-active substance.  The aqueous solution may be separated and used again.