Patent ID: 6465665
Filing Date: 2002-10-15
Classification: C07J

Abstract:
A continuous process for the recovery of sterols from mixtures of neutral matter obtained from black liquor soap skimmings or tall oil pitch, comprising the steps of:(a) feeding the mixture of neutral matter to a first distillation system where said distillation system comprises: a rectifying column, condenser and thin film reboiler so as to form a first fraction comprising long chain aliphatic alcohols and a second fraction comprising sterols and esters; (b) recovering said first and second fractions; (c) feeding said second fraction to a second distillation system comprising a short path distillation column so as to form a third fraction comprising sterols and a fourth fraction comprising esters; (d) recovering said third and fourth fractions; (e) dissolving said third fraction so as to form a solution in a mixture comprising a liquid hydrocarbon solvent, short chain aliphatic alcohol and water; (f) cooling the solution of step (e) so as to form a precipitate; (g) separating the precipitate formed in step (f) from the mother liquor; (h) evaporating the mother liquor of step (g) so as to form a residue; and (i) mixing the residue of step (h) with the mixture of neutral matter of step (a).