Carboxylic Acids, Fatty Acids from Tall Oil

Abstract

Abstract Tall oil fatty acids (TOFA) consist primarily of oleic and linoleic acids and are obtained by the distillation of crude tall oil. Crude tall oil, a by‐product of the kraft pulping process, is a mixture of fatty acids, rosin acids, and unsaponifiables. These components are separated from one another by a series of distillations. Several grades of TOFA are available depending on rosin, unsaponifiable content, color, and color stability. Typical compositions of tall oil fatty acid products are shown. Tall oil fatty acids have a variety of applications. The largest uses of TOFA traditionally have been in coatings, primarily alkyd resins where grades of higher rosin content predominate. Since the 1970s their use as chemical intermediates in applications, which includes manufacture of dimer acids and epoxidized TOFA esters, has exceeded their use in coatings. The more highly refined, low rosin grades are required for their application as intermediates. Other areas of significant use are in soaps, detergents, and ore flotation. Worldwide crude tall oil fractionating capacity and domestic production and prices of TOFA are given. TOFA pricing is strongly dependent on soya fatty acid prices since these materials are often used in the same application.