Biorefining of crude tall oil

A process for the refining of crude tall oil (CTO), wherein the process comprises fractionation under vacuum of a refined CTO into at least one stream of refined tall diesel (RTD) or tall oil fatty acids (TOFA), said RTD or TOFA comprising from 2-30% by volume of resin acids and from 20-90% by volume of fatty acids, characterized by that the refined CTO is charged to a first fractionation step for separation of tall oil fatty acids (TOFA) and resin acids (RA) from tall oil pitch (TOP) followed by a second fractionation step wherein a stream rich in RTD or TOFA components having a boiling point at atmospheric pressure in a range of 170-420° C. is separated from a stream rich in RA, which RA is further purified in a third step being a RA purification step, so that the fractionation also yields at least one stream of RA comprising less than 5% by volume of fatty acids.

A process for the production of a refined tall diesel (RTD) composition with low density, characterized by that crude sulphate turpentine(s) (CST) is added to the refined tall diesel (RTD) composition.

A refined tall diesel (RTD) composition comprising 1-30 wt. % resin acid(s) (RA) and 70-95 wt. % fatty acid(s) (FA), characterized by that it further comprises 1-10 wt. % crude sulphate turpentine(s) (CST) and 0-1 wt. % anthraquinone.