Patent ID: 6069262
Filing Date: 2000-05-30
Classification: C07C

Abstract:
In a process wherein fatty acids are reacted with hydroxyalkyl sulfonic acid salt to yield a corresponding isethionate fatty acid ester, the steps comprising:(a) mixing together and heating in a reaction vessel a molar excess of fatty acids of formula (I):RCOOH (I)containing from 8 to 24 carbon atoms, with a 2-hydroxyalkyl sulfonic acid salt of formula (II):HOR.sup.1 SO.sub.3 X (II)wherein R.sup.1 is a saturated or unsaturated straight chain C2-C4 hydrocarbyl group selected from the group consisting of ethylene, propylene and butylene;and X is selected from the group consisting of sodium, potassium, lithium, ammonium, calcium, magnesium, barium, amines, and triethanol amines;in the absence of sufficient acid or alkaline agents to catalyze the reaction;(b) returning all distillate fatty acids to the reaction vessel;(c) allowing the reaction to proceed substantially toward completion under conditions sufficient to maintain the fluidity of the reaction mixture while continuously removing water from the reaction mixture, until no further condensation can be achieved in the reaction vessel;(d) discontinuing return of the distillate fatty acids and progressively reducing the pressure in the reaction vessel containing said reaction mass while maintaining the fluidity of the reaction mixture;(e) distilling off free, unreacted fatty acids from the reaction mass by stripping at a temperature in the range of 200.degree. C. to 250.degree. C.; and(f) releasing the vacuum, discharging and flaking the isethionate fatty acid ester so formed.