Process for separating unsaponifiable valuable substances from sulphate soap based materials

A process for obtaining a product rich in unsaponifiable valuable substances from at least one of crude sulphate soap, crude tall oil or tall oil pitch, comprising the steps of:

• (a) providing a feed of at least one of crude sulphate soap, saponified crude tall oil or saponified tall oil pitch,
• (b) drying the feed of step (a) to produce a dried feed;
• and
• (c) subjecting the dried feed to a first high vacuum evaporation to obtain a product rich in unsaponifiable valuable substances in the form of a distillate,
• wherein a softener is incorporated into said dried feed at any point prior to step (c), to produce a mixed feed,
• wherein said softener possesses the following properties at the operation conditions of the process:
• (i) the viscosity of the mixed feed having the softener incorporated therein is lower than the viscosity of the feed without the softener;
• ii) the vapour pressure of the softener is lower than the vapour pressure of the unsaponifiables of the feed;
• iii) the molecular weight of the softener is at least 750;
• and, optionally,
• iv) the softener is substantially immune to degradation and other side reactions caused by heat.