Patent GB-633644-A (GB)
Title: Improvements in or relating to demulsifying compositions
IPC: C10G33/04
Filed: 1947-04-28
Abstract: A demulsifying composition for use in breaking either oil-in-water or water-in-oil emulsions of mineral, vegetable, or synthetic oils, waxes, resins and the like comprises a mixture of a surface-active ester of a sulphopolycarboxylic acid and an aspartate amide of an aliphatic sulphopolycarboxylic acid of the general formula <FORM:0633644/III/1> in which R is the residue of an aliphatic polycarboxylic acid, R1 is an alkyl or alkoxyalkyl radicle of 8-18 carbon atoms, R2 and R3 are hydrogen, cationic salt-forming radicles or alkyl radicles, n is 1 or 2, and each X is hydrogen or a cationic salt-forming radicle.  The preferred proportions of the mixture are 5-9 parts of surface-active ester to 1-5 parts of aspartate amide. For breaking emulsions, the mixture is preferably used in proportions of 0.025 to 0.25 per cent of the emulsion to be broken, although as little as 0.01 per cent is sometimes effective.  Other known demulsifying agents such as salts of aromatic sulphonic acids or their condensation products with aldehydes, alkylated aryl sulphonates, sodium keryl benzene sulphonate, and ethylene oxide condensation products of alkylol amides of higher fatty acids such as ethanol stearamide may be added.  In an example, an emulsion prepared by agitating 25 parts of sea water with 75 parts California crude petroleum was broken by 0.03 per cent of a demulsifying composition consisting of a mixture of triamyl sulphotricarballylate and N-dodecyl-N-(disodium sulphosuccinyl)-dimethyl aspartate dissolved in isopropanol.  The preparation of various aspartate amides is described (see Group IV (b)).  U.S.A. Specifications 2,072,085 and 2,315,375 are referred to.ALSO:Aspartate amides of aliphatic sulphocarboxylic acids of the general formula <FORM:0633644/IV (b)/1> in which R is the residue of an aliphatic polycarboxylic acid, R1 is an alkyl or alkoxyalkyl radicle of 8-18 carbon atoms, R2 and R3 are hydrogen, cationic salt-forming radicles or alkyl radicles, n is 1 or 2, and each X is hydrogen or a cationic salt-forming radicle, for use in demulsifying compositions (see Group III], are prepared by treating a solution of an alkylamine in t.-butanol with an ester of maleic acid and slowly adding maleic or aconitic anhydride and heating.  The resulting products are poured into hot solutions of sodium sulphite and heated for about an hour.  The esters may be converted into the sodium salts by saponification with excess sodium hydroxide.  Compounds so prepared include N - dodecyl - N - (disodium sulphosuccinyl)-dimethyl and disodium aspartates, N-octadecyl-N-(disodium sulphocuccinyl)-dimethyl, and disodium aspartates, N-amyloxypropyl-N-(disodium sulphosuccinyl)-dimethyl aspartate, trisodium N-octadecyl-N-(1.2-di-carbomethoxyethyl) - sulphotricarballylamate, and the pentasodium salt of the formula <FORM:0633644/IV (b)/2> The demulsifying compositions described may be used inter alia in separating the emulsion formed in the extraction of vanillin from neutralized sulphite liquor with benzene. U.S.A. Specifications 2,072,085 and 2,315,375 are referred to.