| 摘要 |
The invention relates to a process for recovering fatty acids, resin acids and sterols from tall oil pitch, said process comprising a) saponifying the tall oil pitch with an alkali to hydrolyse esters included in the pitch to free alcohols and organic acids in salt form, b) acidulating the saponified pitch with a mineral acid to convert the organic acids in salt form into free organic acids and to form an organic phase and an aqueous phase, c) separating the aqueous phase from the organic phase, d) evaporation fractionating the organic phase to obtain a distillate rich in sterols, fatty acids and resin acids, e) evaporation fractionating the distillate to obtain a bottom fraction rich in sterols, and a distillate rich in fatty acids and resin acids, and f) subjecting the sterols in the sterol-rich bottom fraction to crystallization purification. The invention also relates to an alternative process including steps a) to c) followed by d1) treating the organic phase with an alkali to destroy excess mineral acid used for acidulating the saponified pitch, e1) evaporation fractionating the alkali-treated organic phase to obtain a distillate rich in fatty acids and resin acids and a bottom fraction rich in sterols, f1) evaporation fractionating the bottom fraction to obtain a distillate rich in sterols, and g1) subjecting the sterols in the sterol-rich distillate to crystallization purification. |
