VERFAHREN ZUR GEWINNUNG VON HOCHREINEN FETTSAEUREN, HARZSAEUREN UND STERINEN

摘要

A process for recovering fatty acids and/or rosin acid with a high purity which comprises first introducing a tall oil skimming soap or a tall oil soap into a thin film evaporator equipped with a rake in which the clearance between the blade tips and the surrounding evaporator wall is zero or not more than 1 mm, heating the same at a temperature higher than the melting point of the soap contained therein to evaporate and remove water and unsaponifiables, and then adding an alkali to the thus obtained crude soap to saponify the same, thereby decomposing the esters of rosin acid and fatty acids with sterols and other alcohols; or first saponifying a tall oil skimming soap or a tall oil soap with an alkali to decompose esters of rosin acid and fatty acids with sterols and other alcohols, and then introducing the thus obtained saponification product to the above-said thin film evaporator equipped with a rake, heating the same at a temperature higher than the melting point of the soap contained therein to evaporate and remove water and unsaponifiables; followed by subjecting the resultant saponification product to acid decomposition and distillation, thereby obtaining the desired fatty acids and/or rosin acid. In the above process, it is possible to recover not only the high purity fatty acids and/or rosin acid but also sterols by introducing, prior to the acid decomposition, the saponification product into the above-mentioned thin film evaporator equipped with a rake and then heating the same at a temperature higher than the melting point of the soap contained therein to evaporate and separate sterols and heavy unsaponifiable matters.