Tall oil fatty acids are a product of crude tall oil vacuum distillation. The fraction of tall oil fatty acids is represented by linolic, linolenic, oleinic and other acids. The fraction of tall oil fatty acids is obtained after separation of tall oil pitch, tall oil rosin, and distilled tall oil fractions, as well as a fraction of unsaponifiable matters.

Crude fatty acid is obtained in a column, at its lower part takes place an extraction of resin acids fraction. After separation of unsaponifiable matters from crude fatty acid is realized its rectification. At that tall oil fatty acids are obtained in the upper part of final column and also small amount of distilled tall oil with high resin acids content in its lower part.

Tall oil fatty acid contain up to 2 % of remaining resin acids. By way of changing the distilling process parameters is possible to get tall oil fatty acids with resin acids content up to 1%.