The invention relates to a process for recovering sterols and a fraction rich in fatty acids and resin acids from tall oil pitch, said process comprising a) saponifying the tall oil pitch with an alkali to hydrolyse esters included in the pitch to free alcohols and organic acids in salt form, b) acidulating the saponified pitch with a mineral acid to convert the organic acids in salt form into free organic acids and to form an organic phase and an aqueous phase; wherein mineral acid is provided in an amount to produce an aqueous phase with a pH value of at most 3.8, c) separating the aqueous phase with a pH value of at most 3.8 from the organic phase, d) evaporation fractionating the organic phase in a thin film evaporator to obtain a distillate rich in fatty acids and resin acids and a bottom fraction rich in sterols, e) evaporation fractionating the bottom fraction to obtain a distillate rich in sterols, and f) subjecting the sterols in the sterol-rich distillate to crystallisation purification, wherein the process excludes a step of adding alkali between step c) and step d).

The invention relates to a process for recovering sterols and a fraction rich in fatty acids and resin acids from tall oil pitch, said process comprising a) saponifying the tall oil pitch with an alkali to hydrolyse esters included in the pitch to free alcohols and organic acids in salt form, b) acidulating the saponified pitch with a mineral acid to convert the organic acids in salt form into free organic acids and to form an organic phase and an aqueous phase; wherein mineral acid is provided in an amount to produce an aqueous phase with a pH value of at most 3.8, c) separating the aqueous phase with a pH value of at most 3.8 from the organic phase, d) evaporation fractionating the organic phase in a thin film evaporator to obtain a distillate rich in fatty acids and resin acids and a bottom fraction rich in sterols, e) evaporation fractionating the bottom fraction to obtain a distillate rich in sterols, and f) subjecting the sterols in the sterol-rich distillate to crystallisation purification, wherein the process excludes a step of adding alkali between step c) and step d).

A method to produce crude tall oil (CTO) having a reduced sulfur content is disclosed. Black liquor soap (BLS) is treated with 0.05 to 0.45% by weight H.sub.2O.sub.2. Hydrogen peroxide treated BLS compositions, CTO compositions, and chemical compositions derived thereof, including depitched CTO, TOP, depitched CTO distillation fractions, and products derived therefrom are disclosed. The use of a small amount of H.sub.2O.sub.2 results in a decreased degree of foaming.

The present invention describes a process for continuous fractionation of CTO (crude tall oil) to RTD (refined tall diesel), said process comprising:—when removing a stream of TOP (tall oil pitch) the CTO is fed through at least two evaporation zones arranged in series so that one stream of CTO is fed from a first evaporation zone to a second evaporation zone, wherein a TOP stream is produced and fed from the second evaporation zone, wherein a first vapor stream is produced within the first evaporation zone and a second vapor stream is produced within the second evaporation zone and wherein there is a temperature difference of at least 10° C. between the first vapor stream and the second vapor stream; and—feeding the first vapor stream and the second vapor stream into a subsequent fractionation column to produce a stream of RTD from the fractionation column, wherein the first vapor stream and the second vapor stream are being fed to different positions, relative to the column height, in the fractionation column, where different conditions are applied to ensure suitable fractionations of a more fatty acid rich material and a more rosin rich material, respectively, and which different positions in the fractionation column are separated by packing means.

The present invention relates to fractionation of crude tall oil, which originates from the Kraft process black liquor. In the method, according to the present invention, simulated moving bed (SMB) chromatography is used to efficiently separate fractions from the crude tall oil.

The present invention describes a process for continuous fractionation of CTO (crude tall oil) to RTD (refined tall diesel), said process comprising:—when removing a stream of TOP (tall oil pitch) the CTO is fed through at least two evaporation zones arranged in series so that one stream of CTO is fed from a first evaporation zone to a second evaporation zone, wherein a TOP stream is produced and fed from the second evaporation zone, wherein a first vapor stream is produced within the first evaporation zone and a second vapor stream is produced within the second evaporation zone and wherein there is a temperature difference of at least 10° C. between the first vapor stream and the second vapor stream; and—feeding the first vapor stream and the second vapor stream into a subsequent fractionation column to produce a stream of RTD from the fractionation column, wherein the first vapor stream and the second vapor stream are being fed to different positions, relative to the column height, in the fractionation column, where different conditions are applied to ensure suitable fractionations of a more fatty acid rich material and a more rosin rich material, respectively, and which different positions in the fractionation column are separated by packing means.

A method to purify black liquor soap (BLS) from sulfur compounds is disclosed. In the BLS desulfurization method, a BLS composition is heated in an inert atmosphere and sulfur is removed via aqueous extractions with inorganic base in the absence of other chemicals such as brine, sulfate salts and carbonate salts. The purified BLS composition exhibits favorable properties, including reduced sulfur content, lower color, and improved odor characteristics. The resulting tall oil compositions, depitched tall oil compositions, tall oil distillation fractions, and products derived therefrom also show reduced sulfur content, lower color, and improved odor characteristics.

A process for reducing or removing at least 90% of sulfur in a tall oil composition, e.g., to a level of 15 ppm or less is disclosed. The process employs at least a first desulfurization and a second desulfurization treatment in parallel or in series. The first treatment comprises adsorptive desulfurization, wherein the adsorbent material comprises silica adsorbent having an average pore size between 50-200 Å, BET surface area of at least 300 m.sup.2/g, pore volume of 1.20 to 3.00 cc/g, and a silanol [Si—OH] level of 0.5 to 5 unit/nm.sup.2. The second desulfurization treatment is selected from adsorptive treatment, heat treatment, distillation, extraction, oxidation, reduction, hydrogenation, and sulfur scavenging for a reduced sulfur content.

Provided are methods and systems for treating a soapstock. Provided are systems and methods for treating a soapstock to generate free fatty acids and/or fatty acid derivatives, and for realizing the full fatty acid yield of a soapstock by first converting substantially all of the saponifiable material in a soapstock to fatty acids and acidulating the soaps to generate free fatty acids and/or fatty acid derivatives, wherein the soapstock comprises soaps and saponifiable lipids, and the generating of free fatty acids is achieved. Provided are systems and methods for realizing the full fatty acid yield of a soapstock by first converting substantially all of the saponifiable material in a soapstock to salts of fatty acids and acidulating the soaps to generate free fatty acids and/or fatty acid derivatives, wherein the soapstock comprises soaps and saponifiable lipids, and the generating of free fatty acids is achieved.

The disclosure relates to a method for refining crude tall oil, wherein the method comprises first evaporating tall oil material (10) in a first evaporator (100) whereafter the first fraction (11) is fed to a first distilling column (200) and the second fraction (12) is fed to further evaporation. The condensate(s) recovered from the further evaporation(s) is fed to a second distilling column (300).

The present disclosure further concerns the use of different fractions obtained by the method for the production of biofuels or components thereof.