RU2793168C1 - Method for obtaining phytosterols and stanols extract from tall pitch and phytosterols and stanols extract obtained by the specified method - Google Patents

Abstract

FIELD: oil and fat industry.

SUBSTANCE: method for producing an extract of phytosterols and stanols from tall pitch, comprising the following steps: a) providing the presence of tall pitch; b) saponifying tall pitch to produce saponified tall pitch by adding a base selected from one or more of NaOH, KOH and CsOH to the tall pitch; c) extracting the saponified tall pitch using one or more non-polar aromatic solvents to obtain a solution containing a mixture of neutral substances; d) performing a distillation of a mixture of neutral substances to obtain a distillate fraction and a residual fraction; e) dissolving the distillate fraction in the solvent mixture to obtain a dissolved distillate fraction. It also contains a crystallization step (f), which is carried out in relation to the dissolved fraction of the distillate under crystallization conditions, to extract the mother liquor and the crystallized fraction, while the crystallized fraction forms an extract of phytosterols and stanols, and the solvent mixture used in the implementation of step (e), contains from 10 to 60 % by weight of one or more non-polar solvents, based on the total weight of the solvent mixture; 23 to 40 % by weight of one or more solvents having a ketone component, based on the total weight of the solvent mixture; from 2 to 20 % by weight of one or more monohydric alcohols, based on the total weight of the solvent mixture; and 0.5 to 2.5 % by weight water, based on the total weight of the solvent mixture.

EFFECT: extract of phytosterols and stanols, obtained from tall pitch by the above method, while it contains at least 65% (by weight) α-sitosterol, based on the total weight of the extract of phytosterols and stanols, and less than 0.01% (by weight), based on the total weight of the extract of phytosterols and stanols, each of the following components: oxysterols, α-sitosterol and betulin, the content of which is determined in the process of gas chromatography using a flame ionization detector as an analyser.

14 cl, 2 dwg, 9 tbl, 3 ex

Description

The field of technology to which the invention belongs

The present invention relates to a method for the production of an extract of phytosterols and stanols from tall pitch.

Prior Art

Phytosterols and stanols can be found in almost all plants; they are usually available commercially as an extract. One of the main components in this type of extract is β-sitosterol, which is very similar in composition to cholesterol. β-sitosterol (or its derivatives) when taken orally provides a hypocholesterolemic effect.

The idea of extracting β-sitosterol from plants is therefore interesting in that it provides the possibility of obtaining raw materials for the manufacture of pharmaceuticals and/or foods that help lower blood cholesterol levels. To obtain β-sitosterol from plants, it is necessary to isolate the phytosterol contained in them using various methods for this purpose, including distillation, extraction and/or crystallization. The use of such methods often leads to the production of sterol concentrates containing β-sitosterol in its composition, but also containing β-sitosterol, campesterol, stigmasterol, brassicasterol, β-sitostanol, campestanol, oxysterols, triterpene alcohols, as well as other components, for example, fatty alcohols. During the isolation of β-sitosterol, other components such as fibres, lignin materials and inorganic salts must also be removed.

A good source of phytosterols is crude tall oil, which is a by-product of the wood pulp kraft process. The crude tall oil fractionation process produces tall oil pitch as a sludge, which can then be processed to produce a sterol concentrate. Tall pitch consists of esters of fatty and resin acids, their oligomers and oxidized derivatives, high-boiling neutral substances (hydrocarbons, alcohols, including phytosterols , etc. ...), as well as lignin.

US 6,465,665 describes a continuous process for the recovery of sterols from a mixture of neutral substances derived from tall oil tar. This mixture of neutral substances is obtained in the process of saponification and extraction, together with petroleum ether of tall oil pitch. This method allows you to perform the extraction of a neutral substance with a content of sterols equal to 41.8%. After extraction of the neutral substance, it is distilled using a distillation column, which makes it possible to obtain the first fraction of long-chain aliphatic alcohol and the second fraction of sterols and esters. The second fraction goes through a second distillation process to separate sterols and esters. The sterol fraction is then dissolved to produce predominantly liquid hydrocarbons, but also (potentially) alcohol and/or water. The solution is then cooled to allow the formation of a precipitate which separates from the mother liquor. The mother liquor evaporates to form a precipitate, which is added to the mixture of neutral substances before it is distilled. In conclusion, it should be noted that the yield of sterol recovered from tall pitch using the described method is 94.7%, and the degree of purity of sterols exceeds 95%. This method, however, does not provide for the production of β-sitosterol or even a mixture with a high content of β-sitosterol.

US 3,965,085 describes a soap refining process in which unsaponifiable neutrals, known to drastically degrade crude tall oil, are separated by an extraction process using low molecular weight ketones (e.g., acetone and/or methyl ethyl ketone) in combination with water-immiscible solvents such as liquid hydrocarbons. Low molecular weight ketones can indeed prevent the formation of emulsions in soap solutions and are easily removed, even in acidic environments. During the extraction process, the organic phase contains unsaponifiables and the aqueous phase contains fatty acid salts and resin acids. The organic phase and the aqueous phase can then be separated, allowing the recovery of refined tall oil with a neutral content of only 1.6%. Further processing of the organic phase, such as evaporation and crystallization, allows the recovery of a sterol concentrate with a β-sterol content of at least 80%. However, the study mentions that the sterol concentrate also contains campesterol, fatty alcohols, and triterpene alcohols.

Document WO 2019/050430 describes a method for extracting phytosterols from tall pitch. Said method comprises the step of saponification of tall pitch using alkali in polyhydric alcohol. The unsaponifiables are then collected and extracted from an alkaline-alcohol solution using a mixture of paraffinic hydrocarbons as a solvent. After removal of the solvent during distillation, betulin was isolated (by crystallization), which is a triterpene alcohol and cell poison, and phytosterols were evaporated during the rectification process. Thus, this method provides the final product with a phytosterol content of at least 65% and with a content of undesirable impurities of not more than 0.3%. Although this method makes it possible to obtain a sterol concentrate that does not contain one specific component ( i.e., betulin), it is still not possible to achieve extraction of β-sitosterol from tall oil tar at an increased concentration, because said document generally only describes a process for the extraction of high grade phytosterols. To obtain a final product with a high content of β-sitosterol, which could then be used for the preparation of pharmaceuticals and/or food products, it is necessary to achieve the removal of additional components.

US 2008/0161586 describes a process for extracting sterols from tall oil tar. After obtaining a mixture of neutral substances, fatty alcohols are removed by distillation. The non-volatile residue is then crystallized at 50°C to 70°C using a hydrocarbon solvent, alcohols and water. In the example of this invention, gas chromatographic (GC) analysis of the anhydrous sterols showed that the purity of the extract was 86.7% (sterols and stanols content); while it contains almost 10% fatty alcohols (solid hydrocarbons). Among the indicated amount of sterols and stanols (86.7%), 6.3% is campesterol, 1% is ergostanol, 1% is stigmasterol, 69.5% is β-sitosterol and 9% is β-sitostanol (stigmastanol).

The object of the present invention, therefore, is to provide a method by which an improvement in the quality of the extract of phytosterols and stanols obtained from tall pitch can be achieved.

The essence of the invention

According to the first aspect of the invention, a method is provided for obtaining an extract of phytosterols and stanols from tall pitch, this method comprising the following steps

a) ensure the presence of tall pitch;

b) saponifying tall pitch to obtain saponified tall pitch by adding a basic compound to tall pitch;

c) extracting the saponified tall pitch using one or more non-polar aromatic solvents to obtain a solution containing a mixture of neutral substances;

d) performing a distillation of a mixture of neutral substances to obtain a distillate fraction and a residual fraction;

e) dissolving the distillate fraction in the solvent mixture to obtain a dissolved distillate fraction;

said method is characterized in that it further comprises a crystallization step (f) which is carried out in application to a dissolved fraction of the distillate under crystallization conditions to recover a mother liquor and a crystallized fraction, wherein the crystallized fraction forms an extract of phytosterols and stanols; and also by the fact that the mixture of solvents used in the implementation of step (e) contains one or more non-polar solvents, while one or more solvents have a ketone component, one or more monohydric alcohols and water.

Surprisingly, it was found that when running the process using a mixture of neutral substances derived from tall tar, it was possible to obtain an improved extract of phytosterols and stanols, with a higher content of β-sitosterol and a lower content of impurities. The mixture of neutral substances is first purified in the distillation process to obtain the volatile fraction of the distillate. The volatile fraction of the distillate is dissolved in a mixture of solvents and sent to the crystallization stage. The use of the specific solvent mixture used according to the invention provides a very efficient crystallization process. As a result, it becomes possible to obtain a final extract of phytosterols and stanols with improved characteristics and an increased content of the most important sterols and stanols. Unwanted impurities such as α-sitosterol and oxysterols are removed during the crystallization step. In addition, no triterpene alcohols ( eg, betulin) were found in the final extract. Last but not least, the method presented in this invention makes it possible to obtain an extract with a high content of β-sitosterol.

With regard to the crystallization step, it was found that in order to obtain the desired purified extract, it was necessary to use a solvent that is a mixture of at least four solvents. Indeed, the use of a non-polar solvent makes it possible to dissolve di- and triterpene hydrocarbons and condensed products, the source of which is tall oil pitch. The ketone moiety is a substance capable of dissolving α-sitosterol. Monohydric alcohols dissolve sterols. Water starts the process of crystallization of sterols.

In a preferred embodiment, step (c) of extracting the saponified tall pitch using one or more non-polar aromatic solvents is carried out at a temperature value in the range of 80°C to a value that is at least 10°C lower than the boiling point value of one or several non-polar aromatic solvents; preferably, at a temperature value in the range from 85°C to a value that is at least 15°C lower than the boiling point of one or more non-polar aromatic solvents.

If required, after step (c) and before step (d), a step is carried out in which the solution containing the mixture of neutral substances is evaporated.

The method presented in the present invention can be carried out using any mixture of neutral substances obtained from tall pitch. However, it has surprisingly been found that the amount of the mixture of neutrals obtained from tall pitch can be increased by carrying out the extraction of saponified tall pitch using one or more non-polar aromatic solvents.

Preferably, one or more non-polar aromatic solvents used in step (c) are selected from toluene and/or xylene; more preferably, toluene is used as the non-polar aromatic solvent in step (c).

In a preferred embodiment, distillation step (d) comprises one or more distillation sub-steps such that distillation step (d) comprises the following:

d1) performing a first distillation of a mixture of neutral substances to obtain a first distillate fraction and a first residual fraction;

d2) performing a second distillation of the first residual fraction to obtain a second distillate fraction and a second residual fraction;

d3) if required, perform one or more distillations of the second residual fraction and further residual fractions, to obtain one or more distillate fractions and one or more residual fractions;

wherein the distillate fraction dissolved in the solvent mixture in step (e) is the second distillate fraction or a mixture of the second distillate fraction with the first distillate fraction and/or at least one further distillate fraction obtained from one or more distillate fractions.

Preferably, if the distillation step (d) comprises one or more distillation sub-steps, the one or more distillation sub-steps of the process are one or more distillation steps carried out using a distillation column.

Preferably, one or more rectification stages are characterized by the following parameters:

The value of the countercurrent coefficient is from 1/1 to 2/1.

The rectification temperature is 240°C to 280°C, preferably 245°C to 275°C.

The distillation column is combined with a countercurrent condenser; preferably, the temperature of the countercurrent condenser is 110°C to 170°C.

Preferably, in order to better formulate the mixture of solvents used in step (e), one or more of the following embodiments are used:

The mixture of solvents used in step (e) contains one or more non-polar solvents selected from pentane, isopentane and/or hexane; preferably, the non-polar solvent is hexane or contains hexane.

The mixture of solvents used in step (e) contains one or more solvents having a ketone moiety selected from acetone and/or methyl ether ketone; preferably, the solvent having a ketone component is acetone or contains acetone.

The mixture of solvents used in step (e) contains one or more monohydric alcohols selected from methanol, ethanol and/or propanol; preferably, the monohydric alcohol is or contains methanol.

In a preferred embodiment, the solvent mixture contains:

10 to 60 wt % of one or more non-polar solvents, based on the total weight of the mixed solvents; preferably, from 15 to 55% (mass.), more preferably, from 20 to 50% (mass.), even more preferably, from 25% to 45% (mass.);

from 23 to 40% (wt.) of one or more solvents having a ketone component, based on the total weight of the mixed solvents; preferably, from 24 to 39% (mass.), more preferably, from 25 to 38% (mass.), even more preferably, from 26 to 37% (mass.);

0.5 to 2.5% (wt.) water, based on the total weight of the mixed solvents; preferably 0.6 to 2.4% (mass), more preferably 0.7 to 2.3% (mass), even more preferably 0.8 to 2.2% (mass) ; And

from 2 to 20% (wt.) of one or more monohydric alcohols, based on the total weight of the mixed solvents; preferably 3 to 18% (mass), more preferably 4 to 17% (mass), even more preferably 5 to 16% (mass)

In a preferred embodiment, when performing step (e), the value of the mass ratio between the mixed solvents and the distillate fraction is from 1.0 to 2.0; preferably, the value of the mass ratio is from 1.1 to 1.7; more preferably, from 1.2 to 1.5; even more preferably 1.2 to 1.4 or 1.2 to 1.3.

To better formulate step (f) of the process, one or more of the following embodiments may be used:

The crystallization conditions in step (f) comprise a crystallization temperature ranging from 15°C to 25°C and/or a crystallization time of at least one hour, preferably at least two hours.

Step (f) further comprises the step of carrying out additional crystallization using a mother liquor to recover additional extract of phytosterols and stanols; wherein the additional crystallization is carried out under the same crystallization conditions as in step (f); preferably, additional phytosterol and stanol extract is added to the phytosterol and stanol extract extracted in step (f).

The method further comprises an additional step of drying the extract of phytosterols and stanols, preferably at a temperature of at least 100°C for at least 1 hour.

Step (f) is performed when the distillate fraction contains 2.5% (wt.) α-sitosterol or less, based on the total mass of the distillate fraction and when determining the specified value using gas chromatography using a flame ionization detector as an analyzer; preferably 2.4% (wt.) α-sitosterol or less; more preferably, 1.7% (wt.) α-sitosterol or less.

Step (f) is performed when the distillate fraction contains at least 20 wt. % sterols, based on the total mass of the distillate fraction and when the indicated value is determined by gas chromatography using a flame ionization detector as an analyzer; preferably at least 25% (wt.)

In a preferred embodiment, the method further comprises the step (g) of washing the extract of phytosterols and stanols using the solvent mixture used in step (f) at a temperature of 10°C to 15°C and/or an additional step of drying the extract of phytosterols and stanols, preferably at a temperature of at least 100°C for at least 1 hour.

According to a second aspect, the invention provides an extract of phytosterols and stanols obtained from tall pitch, where the extract is characterized in that it contains at least 65% (wt.) β-sitosterol, based on the total weight of the extract of phytosterols and stanols, and less than 0.01% (wt.), based on the total weight of the extract of phytosterols and stanols, each of the following components: oxysterols, α-sitosterol and betulin, the content of which is determined by a gas chromatography process using a flame ionization detector as an analyzer.

Description of figures

In FIG. 1 shows the chromatogram obtained for the sample before the crystallization step.

In FIG. 2 shows the chromatogram obtained for the sample after the crystallization step.

Detailed description of the invention

In describing the invention, the following definitions are used:

The terms "comprising", "comprising" and "comprising" in the context of this document are synonymous with the terms "comprising", "includes" or "comprising", "comprising" and are collectively or non-limiting, without excluding the presence of additional, unmentioned subjects, elements or method steps. The terms "comprising", "comprising" and "comprising" also include the term "consisting of".

The numerical ranges listed, referred to by their endpoints, include all integers and, where appropriate, fractional numbers related to the specified range (for example, the definition "from 1 to 5" may refer to the numbers 1, 2, 3, 4 , 5 when referring, for example, to several elements, and may also include the numbers 1.5, 2, 2.75, and 3.80 when referring to, for example, the measurement process). The endpoint enumeration also includes the endpoints themselves referred to (for example, when "1.0 to 5.0" is used, the endpoints 1.0 and 5.0 are also included). Whenever any numerical range is referred to herein, it is also intended to include all of its subranges.

Specific features, structures, characteristics, or embodiments may be combined in any suitable manner, as may be understood by one skilled in the art from this description, to form one or more embodiments.

The present invention provides a method for producing an extract of phytosterols and stanols from tall tar pitch, said method comprising the following steps:

a) ensuring the availability of tall pitch;

b) saponification of tall pitch to obtain saponified tall pitch by adding a basic compound to tall pitch;

c) extracting the saponified tall pitch using one or more non-polar aromatic solvents to obtain a solution containing a mixture of neutral substances;

d) performing a distillation of a mixture of neutral substances to obtain a distillate fraction and a residual fraction;

e) dissolving the distillate fraction in the solvent mixture to obtain a dissolved distillate fraction;

this method is characterized in that it further comprises a crystallization step (f), which is carried out in application to the dissolved fraction of the distillate under crystallization conditions, to extract the mother liquor and the crystallized fraction, while the crystallized fraction forms an extract of phytosterols and stanols; and also by the fact that the mixture of solvents used in step (e) contains one or more non-polar solvents, one or more solvents having a ketone component, one or more monohydric alcohols and water.

Obtaining a mixture of neutral substances from tall pitch

Tall pitch obtained from the rectification of crude tall oil is first saponified by mixing it with one or more basic components (such as NaOH, KOH or CsOH, preferably NaOH) and dissolved in water when the mixture is heated (preferably in a flask under reflux ). Thus, the temperature value in the saponification step may be from 100°C to 200°C, preferably from 110°C to 190°C, most preferably from 120°C to 180°C.

The reaction can take place in a conventional laboratory glassware heated using a countercurrent condenser. Preferably, a Dean-Stark apparatus is used, since it allows water to be removed from the reactor. The removal of water during the course of the reaction helps to achieve thermodynamic equilibrium in the formation of the product, which is saponified tall pitch.

The reaction time is at least one hour, preferably at least two hours, more preferably at least three hours. The progress of the reaction can be controlled by monitoring the development of the formation of water (taking into account also the amount of water necessary to dissolve the main component), which is removed during the reaction, and possibly also collected through the use of a Dean-Stark apparatus.

Once the reaction is complete, the reaction medium is cooled to room temperature and the saponified tall pitch is extracted. Any sorting funnel can be used. Preferably, continuous extraction may be carried out using a Soxhlet apparatus.

Preferably, the extraction is carried out at a value

temperature from 80°C to a value at least 10°C lower than the value of the boiling point of the extraction solution. More preferably, the extraction temperature is from 85°C to at least 15°C lower than the boiling point of the extraction solution. The extraction temperature is not less than 80°C and not more than 270°C.

Aromatic non-polar solvents were used, such as toluene and/or xylene, which provide a yield of a mixture of neutral substances obtained from tall oil tar at a level of at least 45%. Preferably, toluene is used.

Other solvents can be used, such as paraffinic solvents, cycloparaffinic solvent and/or terpene hydrocarbon. Preferably, the paraffin solvents are selected from hexane, heptane, octane, decane, dodecane, tridecane, undecane, petroleum ether (eg Nefras-C2) or mixtures thereof. The cycloparaffin solvent is preferably decalin. Terpene hydrocarbon solvents are preferably selected from turpentine without pinene and/or hydrogenated terpene hydrocarbons. These solvents ensure the yield of a mixture of neutral substances obtained from tall pitch at a level of at least 30%, and a mixture of neutral substances obtained from tall pitch at a level of not more than 44%.

A mixture of neutral substances of tall pitch contains basic phytosterols (β-sitosterol, campesterol) and stanols (sitostanol, campestanol). Also present is up to 5% (wt.) α-sitosterol (also called citrostandienol). The mixture also contains fatty alcohols such as dehydro-4-abietol; pimara-7,15-dien-3-ol; behenyl alcohol and/or lignoceryl alcohol. In the mixture of neutral substances of tall pitch, other components can be found, such as stigmastane-3,5-diene; Δ5-avenasterols; 24-methylcycloartanol; methyl bethulate; betulin and/or oxysterols.

Separation of β-sitosterol using one or more rectification procedures

In order to obtain an extract of phytosterols and stanols of high purity with a high content of β-sitosterol, it is necessary to purify the mixture of neutral substances.

The first step of this purification is carried out by carrying out at least one distillation; preferably at least one rectification.

The rectification process is one of the options for the practical implementation of distillation; it involves the fractionation of the crude oil. If the distillate obtained from the distillation process is distilled again, a new distillate will be obtained with an even higher concentration of volatile components. The concentration of volatile components in the distillate increases with each repetition of this procedure. In practice, this process of such multi-stage distillation is carried out in the form of countercurrent distillation (rectification) in a distillation column. The distillation column has an inlet pipeline and an outlet pipeline. The liquid mixture to be separated ( i.e., feedstock) is fed to the bottom of the column through the inlet line, where it is brought to the boiling point. The resulting steam moves up inside the column, exits at the top of the column (through the exhaust pipe) and is condensed using a countercurrent condenser. Part of the condensate is removed as a high quality product. The remainder flows back into the column and moves down as a liquid reverse phase.

The distillation temperature (namely, inside the distillation column) is preferably 240°C to 280°C, more preferably 245°C to 275°C, even more preferably 250°C to 270°C, and even more preferably, from 255°C to 265°C.

The temperature value at the bottom of the distillation column is preferably 250°C to 285°C, more preferably 255°C to 280°C, even more preferably 260°C to 275°C, and even more preferably, from 255°C to 270°C.

The temperature value of the counterflow condenser is preferably 110°C to 170°C, more preferably 115°C to 165°C, even more preferably 120°C to 160°C, and even more preferably 125° C to 155°C.

The condensate temperature is preferably 150°C to 210°C, more preferably 155°C to 205°C, even more preferably 160°C to 200°C, and even more preferably 165°C up to 195°C.

The pressure at the top of the column is preferably between 0.05 mbar and 0.35 mbar.

The pressure at the bottom of the column is preferably between 2 mbar and 6 mbar.

In general, in order to increase the amount of basic sterols in the distillate fraction, the residual fraction resulting from the first distillation is processed using another distillation or rectification step. In this way, it is possible to obtain a distillate fraction containing from 25 to 55% (wt.) sterols, based on the total mass of the distillate fraction. The rate of extraction of sterol from the neutral substance of tall pitch in the volatile fraction of the distillate is at least 80%. This distillate fraction also typically contains 0.5 to 1.7 wt % α-sitosterol, based on the total weight of the distillate fraction. At the same time, α-sitosterol accumulates in the non-volatile residual fraction at a concentration of 1 to 4% (wt.) based on the total mass of the non-volatile residual fraction, while other sterols in the non-volatile residual fraction show a concentration of 7 to 30 % (wt.), based on the total weight of the non-volatile residual fraction.

Removal of impurities by crystallization of β-sitosterol

The rectification process provides a fraction of the distillate containing the main sterols (campesterol and β-sitosterol) in the required amount, but also containing impurities such as α-sitosterol, oxysterols and betulin.

Thus, a crystallization process is used to remove the impurities mentioned above.

Preferably, the crystallization is carried out when the distillate fraction contains a low amount of α-sitosterol. Such a "low amount" may mean 2.5% (wt.) α-sitosterol or less, based on the total weight of the distillate fraction and when determining the indicated value using a gas chromatographic flame ionization detector-analyzer α-sitosterol (GC-FID); preferably, less than 2.4% (wt.) α-sitosterol; more preferably, less than 2.0% (wt.) α-sitosterol; even more preferably, less than 1.7% (wt.) α-sitosterol.

Also crystallization is preferably carried out when the distillate fraction contains a high amount of sitosterols. Such a "high amount" may mean at least 20% (wt.) sterols, based on the total weight of the distillate fraction and when determined by the specified value using a gas chromatographic flame ionization detector-analyzer (GC-FID); preferably, not less than 21% (wt.); more preferably, not less than 22% (wt.); even more preferably, not less than 25% (mass.).

In addition, crystallization is preferably carried out when the distillate fraction contains a low amount of α-sitosterol, for example, not more than 2% (wt.), And a high amount of sterols, for example, not less than 20% (wt.), where the mass percent is calculated from the total mass of the distillate fraction and is determined using a gas chromatographic flame ionization analyzer detector (GC-FID).

The distillate fraction is first dissolved in a solvent mixture, which is a mixture of at least four different solvents and contains

one or more non-polar solvents,

one or more solvents having a ketone component,

one or more monohydric alcohols and

water.

Each kind of solvent is added for a specific purpose, and the solvent mixture has a different solvent power than each of the components of the mixture.

Non-polar solvents and paraffinic hydrocarbons, in particular, exhibit high solvent power with respect to di- and triterpene hydrocarbons and condensed products (resins) formed from tall oil tar. The longer the paraffinic hydrocarbon chain, the higher its dissolving power. Non-polar solvents can be selected from pentane, isopentane and/or hexane, preferably hexane, which is the best option due to its adequate boiling point.

Monohydric alcohols are excellent solvents for sterols due to their chemical affinity. Water can be added to adjust the dissolving power of the alcohol. One or more monohydric alcohols can be selected from methanol, ethanol and/or propanol, preferably methanol.

The solvent having a ketone moiety is acetone and/or methyl ether ketone, preferably acetone. (Ketones are used to separate α-sitosterol as they increase the solubility of α-sitosterol).

In addition, by adding water, sterols can be recrystallized, as explained in US 6,465,665, the contents of which are incorporated herein by reference.

Preferably, the solvent mixture contains from 10% (wt.) to 60% (wt.) of a non-polar solvent, from 23% (wt.) to 40% (wt.) of a solvent having a ketone component, from 0.5% (wt.) ) to 2.5% (wt.) water and from 2% (wt.) to 20% (wt.) one or more monohydric alcohols, based on the total weight of the mixture of solvents.

The value of the weight ratio between the solvent mixture and the distillate fraction is from 1.00 to 2.00, preferably 1.25.

During crystallization, the entire distillate fraction must be dissolved in the solvent mixture. Heating and/or stirring the solution increases the dissolving power of the solvent. Thus, the temperature can be raised to a dissolution temperature of 35°C to 60°C, preferably 40°C to 55°C.

As soon as the entire fraction of the distillate is dissolved, the stirring process is stopped and the solution is cooled to a temperature, the value of which is from 15°C to 25°C, preferably up to 20°C. In this way, a crystallization process is started which lasts for at least one hour, preferably at least two hours. It should be noted that by carrying out crystallization at room temperature (from 15°C to 25°C) it is possible to obtain an extract of phytosterols and stanols that does not contain triterpene alcohols and, in particular, betulin. This turned out to be an unexpected result, because from document WO 2019/050430 it is known that when the process is carried out at a temperature below 50°C, joint crystallization of betulin and phytosterols is usually observed.

Once all the crystals have been formed from the mother liquor, they can be recovered by the filtration process. If required, the crystals can be washed using a mixture of solvents at a temperature of from 5°C to 10°C.

The mother liquor can also be restored. After evaporation of 25% to 50% of its volume (using a rotary film evaporator), the concentrated portion of the mother liquor is cooled to a temperature in the range of 15°C to 25°C, preferably 20°C, to start a new crystallization process. The crystals can then be collected, which, if required, can be washed using a mixture of solvents at a temperature of from 5°C to 10°C.

After that, both portions of the crystals can be dried, for example, in an oven or drying chamber, preferably at a temperature of at least 100°C, more preferably at least 110°C. The drying process may preferably last at least 1 hour, more preferably at least 2 hours. They can also be dried in a reduced pressure environment ( i.e. vacuum) to speed up the drying process.

The low temperature (5°C to 10°C) used in the crystal washing process prevents the collected crystals from re-dissolving. However, due to the fact that it is not possible to completely prevent re-dissolution, a procedure for cleaning the filtrates can be undertaken. The two filtrates can thus be mixed and cooled down to between 15°C and 25°C, preferably up to 20°C, in order to start a new crystallization process.

Such further actions allow you to extract the maximum amount of phytosterol and stanol extract. The extract of phytosterols and stanols has a crystalline form, contains an increased amount of β-sitosterols and does not contain impurities such as α-sitosterol (but also oxysterols and betulin).

Test methods and determinations

In distillation techniques (including rectification as well), reflux refers to the liquid condensed from the rising vapor which is returned to the reactor flask. Based on this, the "countercurrent ratio" is the ratio of the rates of boiling and selection. In other words, it is the ratio of the amount of reflux flowing back to the bottom of the distillation column and the amount of reflux collected in the receiving tank (as distillate). Thus, if 5 parts of the reflux are returned back to the bottom of the distillation column and 1 part is withdrawn as distillate, the value of the backflow ratio is 5/1. In the case of taking the entire reverse flow as distillate, the backflow coefficient would be equal to zero. If no distillate is being withdrawn, the backflow factor is not used. Instead, the concept of "full irrigation" or "balancing" is used. The higher the value of the backflow coefficient, the closer the contact between the vapor and liquid in the distillation column and the lower the distillate withdrawal rate will be.

Gas chromatography-mass spectrometry (GC-MS) and/or gas chromatography with flame ionization detector (GC-FID) techniques were used to determine the content of the extract of the crystalline product obtained by the process of the present invention.

The GC-MS technique was used to identify and quantify the components. An Agilent 7890B-GC/5977A-MS is being used. A column with 5% phenyl 95% polymethylsiloxane phase is used (HP-5ms 60 m x 0.125 mm x 0.125 µm). The following temperature program is used: start 120°C/5 min, heat up 5°C/min, isotherm 350°C/10 min. Injection parameters: 1 µl, at 350°C with a reset of 1/10. Mobile phase: helium 99.9995%. The transition line temperature is 360°C. MSq program: total ion current, scan mode, 28-800 Da, 70 eV. The NIST-11 mass spectrum library was used. The detection limit of this analytical method is 0.01% (mass).

For the current analysis, the GC-FID method was used. Chromatec-5000 apparatus is used. A column with a polymethylsiloxane phase (SE-30 30 m x 0.125 mm x 0.125 µm) is used. The following temperature program is used: start 50°C/5 min, heat up 5°C/min, isotherm 350°C/10 min. Injection parameters: 1 µl, at 350°C with a reset of 1/10. Mobile phase: nitrogen. The detection limit of this analytical method is also 0.01% (mass).

Karl Fischer titration is an analytical procedure that uses colorimetric or volumetric titration to determine trace amounts of water in a sample.

The sterol extraction rate in Example 1 was determined according to formula (1):

Similarly, in other examples, the sterol recovery rate was determined according to formula (2):

Examples

Embodiments of the present invention will be better understood after analyzing the example below.

Example 1: Obtaining a mixture of neutral substances from tall pitch

Tall pitch saponification

2500 g of tall pitch containing 9.3% (wt.) of the total amount of the six main transformable sterols (according to the data determined during the experiments using the GC-MS method) to which is added 375 g of sodium hydroxide dissolved in 500 g of water. Saponification was carried out at a temperature of 130-135°C for 3 hours using a Dean-Stark nozzle to separate the water formed during the reaction. It should be noted that a significant increase in the volume of the reaction mixture was observed during saponification. At the end of the process, the reaction mixture is drained through a hole in the bottom into an aluminum mold; 2800 g of solid saponified resin was obtained immediately. Using a Fischer titration, it was possible to determine that the alkali content of the solid saponified resin was 7.5% and the water content was 8.1%, according to the total weight of the solid saponified resin). The melting point value was determined to be 117.1°C. At the beginning of the process, water was condensed using a Dean-Stark nozzle, and after 1.5 hours the water was withdrawn. A total of 40 g of water was sampled using the nozzle.

Extraction of saponified tall pitch

Extraction of saponified tall pitch is carried out using a 150 ml glass Soxhlet extractor. Small pieces of hard saponified tall pitch 2-3 mm long were placed in a paper cartridge, which was placed in the extractor. The lower flask was filled with solvent in an amount equal to twice the capacity of the Soxhlet extractor; the solvent was heated to boiling using a countercurrent condenser for 2 hours. The solvent was removed from the surface of this extraction solution using a rotary film evaporator.

Table 1 shows the extraction parameters and the composition of the extracts.

Table 1 : Extraction of saponified tall pitch: conditions and results.

solvent hexane
(boiling point = 68°C) nefras-C2
(boiling point = 120°C) toluene
(boiling point = 110°C) ratio of saponified tall pitch and solvent 1:15 1:12 1:10 Extraction time (in hours) 2 2 2 Extraction temperature (°C) 80 110 100 Extract Yield (%) 25.7 19.3 48.6 Extract composition ^# Total Fatty Alcohols (wt.%) 3.8 3.9 1.8 Total sterols (wt.%) 11.7 13.1 8.3 Total Quantity of Components Determined (wt. %) 61.9 54 46.2 Sterol Recovery Rate from Tall Pitch Neutral Matter (%) 38.4 32.2 52.9

^# determined during experiments using the GC-FID method.

The use of toluene as an extraction solution makes it possible to increase the rate of extraction of sterol from a mixture of neutral substances, using tall pitch as a starting material and processing it using the stages of saponification, extraction and evaporation. Compared to the known results described in Example 1 of US 6,465,665, the recovery rate of sterol using toluene as the extraction solution is increased by 11.1%.

Example 2 Separation of β-sitosterol using one or more rectification procedures

EFFECT: availability of a mixture of neutral substances obtained from tall pitch. Such a mixture may contain up to 5% (wt.) α-sitosterol, according to the total weight of the mixture of neutral substances. Such a mixture of neutral substances can be either as given in example 1 (see its composition in table 1), or another. For example 2, the composition of the mixture of neutral substances is given in table 2 in the column entitled "Material content in the original product".

The mixture is continuously fed into a glass distillation column with an internal diameter of 50 mm and a height of 450 mm. The glass distillation column is also equipped with electrical heating means to compensate for heat loss, one countercurrent condenser and one slime separator in its upper part. It also provides a tank for receiving non-volatile product with a volume of 1 liter, as well as a vacuum system.

First batch of material

The first batch of material, containing a mixture of neutral substances obtained from tall pitch, is fed into a distillation column. After distillation, the first fraction of the distillate contained a low amount of basic sterols (7.2% (mass.)) sterols are still concentrated mainly in the non-volatile residual fraction (26.2% (wt.)). The two main sterols found are campesterol and β-sitosterol. After the first rectification, α-sitosterol was not detected in the distillate fraction. Information on the results and conditions of the first rectification is presented in Table 2.

Table 2 : First rectification of the first batch of material containing a mixture of neutral substances obtained from tall pitch.

RECTIFICATION 1 (first batch of material) The content of the material in the original product (wt.%) Distillate (wt.%) Residue (wt.%) Conditions ^#
Flow rate = 400 ml/h
Temperature (°C)
- rectification = 250
- at the bottom of the column = 260
- condensate = 160
- capacitor = 120
Vacuum level (mbar)
- at the top of the column = 0.09
- at the bottom of the column = 2.8
Backflow ratio = 2/1
^# Analyzes were carried out according to the GC-FID method to determine the composition of the original product, the distillate fraction and the residual fraction. total fatty alcohol content 6.0 27.3 0.4 sitosterol 3.5 0.6 4.5 campestanol 1.6 1.3 1.4 campesterol 4.2 3.2 4.1 β-sitosterol 18.4 4 22.1 Total Sterols 22.6 7.2 26.2 Oxysterols 5.0 not detected not detected α-sitosterol 1.7 not detected 2.1 betulin 2.0 not detected 1.9 heavy components 18.4 1.6 29.6

not found = not found;

after rectification, the yield of the volatile fraction of the distillate is 17%, and the non-volatile residual fraction is 81.6%.

The non-volatile residual fraction (see its composition in table 2) is processed using a different rectification procedure.

Compared to the first distillation procedure, the temperature of the distillation column was increased by 10°C (from 250°C to 260°C). The temperature of the countercurrent condenser has also been increased (from 120°C to 160°C). The value of the counterflow ratio of the distillation column decreased from 2/1 to 1/1, which means an increase in the distillate withdrawal rate.

This makes it possible to obtain a fraction of the distillate with a higher content of basic sterols (44.3% (wt.)) and to detect a small amount (1.2% (wt.)) of α-sitosterol.

Information on the results and conditions for the second rectification procedure is presented in Table 3.

Table 3 : The residual fraction obtained after the first rectification procedure is subjected to the second rectification procedure.

RECTIFICATION 2 (first batch of material) The content of the material in the original product (wt.%) Distillate (wt.%) Residue (wt.%) Conditions ^#
Flow rate = 400 ml/h
Temperature (°C)
- rectification = 260
- at the bottom of the column = 265
- condensate = 200
- capacitor = 160
Vacuum level (mbar)
- at the top of the column = 0.06
- at the bottom of the column = 4
Backflow ratio = 1/1
^# Analyzes were carried out according to the GC-FID method to determine the composition of the original product, the distillate fraction and the residual fraction. total fatty alcohol content 0.4 0.05 not detected sitosterol 4.5 7.5 4.2 campestanol 1.4 2.8 0.5 campesterol 4.1 7.6 1.9 β-sitosterol 22.1 36.7 18 Total Sterols 26.2 44.3 19.9 Oxysterols not detected 7.7 8.9 α-sitosterol 2.1 1.2 2.8 betulin 1.9 not detected 1.5 heavy components 29.6 36.4 32.1

not found = not found;

After rectification, the yield of the volatile fraction of the distillate is 35%, and the non-volatile residual fraction is 65%.

The non-volatile residual fraction (see its composition in table 3) is processed using a different rectification procedure.

Compared to the second rectification procedure, the temperature of the counterflow condenser was reduced by 10°C (from 160°C to 150°C).

A small amount (1.6% (wt)) of α-sitosterol was also found. Information on the results and conditions of the third rectification procedure is presented in Table 4.

Table 4 : The residual fraction obtained after the second rectification procedure is subjected to the third rectification procedure.

RECTIFICATION 3 (first batch of material) The content of the material in the original product (wt.%) Distillate (wt.%) Residue (wt.%) Conditions ^#
Flow rate = 400 ml/h
Temperature (°C)
- rectification = 260
- at the bottom of the column = 265
- condensate = 200
- capacitor = 150
Vacuum level (mbar)
- at the top of the column = 0.06
- at the bottom of the column = 4
Backflow ratio = 1/1
^# Analyzes were carried out according to the GC-FID method to determine the composition of the original product, the distillate fraction and the residual fraction. total fatty alcohol content not detected not detected not detected sitosterol 4.2 7.3 3.2 campestanol 0.5 1.7 0.3 campesterol 1.9 5 1 β-sitosterol 18 32.5 12.3 Total Sterols 19.9 37.5 13.3 Oxysterols 8.9 8 9.3 α-sitosterol 2.8 1.6 3.3 betulin 1.5 0.1 2.2 heavy components 32.1 38.9 37

not found = not found;

after rectification, the yield of the volatile fraction of the distillate is 35%, and the non-volatile residual fraction is 65%.

It is noteworthy that in this case, namely, after performing three stages of rectification, the volatile fraction of the distillate does not contain detectable amounts of fatty alcohols.

Second batch of material

Table 5 shows the results of the rectification of the second batch of neutral substances obtained from tall oil tar using other rectification conditions.

Table 5 : Rectification of the second batch of neutral substances obtained from tall pitch.

RECTIFICATION OF THE SECOND PARTY OF MATERIAL The content of the material in the original product (wt.%) Distillate (wt.%) Residue (wt.%) Conditions ^#
Flow rate = 250 ml/h
Temperature (°C)
- rectification = 260
- at the bottom of the column = 275
- condensate = 200
- capacitor = 140
Vacuum level (mbar)
- at the top of the column = 0.3
- at the bottom of the column = 5
Backflow ratio = 1/1
^# Analyzes were carried out according to the GC-FID method to determine the composition of the original product, the distillate fraction and the residual fraction. total fatty alcohol content 5.1 7 not detected sitosterol 3.6 4.4 2.1 campestanol 1.8 2.6 0.3 campesterol 3.4 4.7 0.8 β-sitosterol 18.2 21.8 8.7 Total Sterols 21.6 26.5 9.5 Oxysterols 4.8 5.8 8.6 α-sitosterol 1.3 0.7 1.9 betulin 1.1 not detected 3.7 heavy components 16.4 16.8 16.5

not found = not found;

after rectification, the yield of the volatile fraction of the distillate is 66%, and the non-volatile residual fraction is 34%;

The rate of extraction of sterol from the neutral substance of tall pitch in the volatile fraction of the distillate, when calculated in accordance with formula (2), is not less than 80.97%.

Under the rectification conditions described in Table 5, the distillate fraction contained an increased amount of basic sterols (26.5% (wt.)). The detected content of α-sitosterol in the distillate fraction was 0.7% (wt.)

Example 3: Removal of impurities by crystallization of β-sitosterol

Example 3A

The volatile fraction of the distillate recovered from the second batch of material (see its composition in table 5) underwent the following further processing:

A glass reactor equipped with a paddle stirrer, a heating jacket, a countercurrent condenser and a 1000 ml dispenser was charged with 200 g of starting material and 248.0 g of a solvent mixture containing hexane, monohydric alcohol, water and acetone to form a mixture. Hexane is present in an amount of 45% (wt.), the monohydric alcohol is methanol, which is present in an amount of 16% (wt.), water is present in an amount of 2% (wt.) and acetone is present in an amount of 37% (wt.) Then the mixture mixed solvents and starting material was subjected to mixing and heating to 45°C through the jacket of the reactor. Stirring was continued until the contents were completely dissolved. After that, heating and stirring were stopped and the mother liquor was cooled to 20°C. The solution was kept at a temperature of 20°C for another 2 hours to ensure the crystallization of β-sitosterol. As a result of crystallization, large crystals of β-sitosterol are formed, which can be carefully filtered from the mother liquor. Once the mother liquor had separated, the crystal mass was placed on a Buchner funnel with a Bunsen flask to remove the remaining mother liquor using vacuum. Crystals of β-sitosterol were washed directly on the filter using a mixture of solvents weighing 150 g at a temperature of 6°C; filtrate was collected.

The mother liquor was placed in a flask of a rotary film evaporator, then 1/3 of the solvent volume was removed. The remaining part was left to ensure further formation of crystals of β-sitosterol under the conditions corresponding to those described above. The procedure described above was used to separate the crystals. Finally, the β-sitosterol crystals were washed out on a Buchner funnel (or on a filter) using a 150 g solvent mixture at 6°C; then the filtrate was collected.

Once the collection procedure for both filtrates was completed, they were mixed and used to recrystallize additional β-sitosterol crystals under the conditions described above.

At this stage, the mother liquor of this crystallization was collected and evaporated using a rotary film evaporator (at a bath temperature of 120° C. and a vacuum value of 10 mbar) to obtain the first non-productive precipitate.

The collection of additional crystals of β-sitosterol and their washing was carried out using a mixture of solvents weighing 25 g at a temperature of 6°C. The wash solution was reconstituted followed by evaporation on a rotary film evaporator (bath temperature 120° C. and vacuum value 10 mbar) to obtain a second non-productive precipitate.

Table 6 shows the composition of the first and second unproductive sediments.

Table 6 : Composition of the first and second non-productive residues obtained during the crystallization of distillate fractions after distillation of the second batch of material.

Component First unproductive sludge
(mass %) ^# Second unproductive sludge
(mass %) ^# total fatty alcohol content 6.2 27.0 sitosterol 2.4 7.1 campestanol 3.3 1.5 campesterol 4.1 7.5 β-sitosterol 9.9 34.4 Total Sterols 14 41.9 Oxysterols 8.7 1.3 α-sitosterol 1.0 0.2 betulin not detected not detected heavy components 26.7 5.0

not found = not found;

^# determined during experiments using the GC-FID method.

The determined yield of the 1st non-productive sludge was 71%, and the determined yield of the 2nd non-productive sludge was 10.15%.

The value of the sterol extraction rate for the first non-productive precipitate and the second non-productive precipitate, when calculated according to the formula (2), respectively, is 37.51% and 16.05%.

Unproductive sludge contains detectable amounts of oxysterols and α-sitosterol. Logically, the amount of these impurities is significantly less in the second non-productive precipitate obtained from the washing solution than in the first non-productive precipitate obtained by evaporation of the mother liquor, consisting of two filtrates.

All crystals of β-sitosterol were collected together and dried to remove the remaining solvent in a drying chamber at a temperature of 115°C for two hours. Table 7 shows the composition of the resulting β-sitosterol crystals.

Table 7 : Crystallization of distillate fractions after distillation of the second batch of material.

Component crystalline product
(mass %) ^# total fatty alcohol content 1.8 sitosterol 12.1 campestanol 1.7 campesterol 14.2 β-sitosterol 67.0 Oxysterols not detected α-sitosterol not detected betulin not detected heavy components 1.4 Total Quantity of Defined Components 98.2 Total content of sterols and stanols 95.0

not found = not found;

^# determined during experiments using the GC-FID method.

The value of the sterol extraction rate when calculated by formula (2) is 56.38%.

The determined yield of the crystalline product was 18.4%, and the total amount of the detected component was 98.2%, as indicated in Table 7. The method of the present invention allows the content of sterols and stanols in the resulting product to be 95% (wt.), with a content of fatty alcohols (solid hydrocarbons) equal to only 1.8% (mass.).

Through the use of the present method (rectification of the neutral substance of tall pitch followed by crystallization of β-sitosterol from the distillate fraction), the final product is a crystal containing mainly β-sitosterol and free of oxysterols, betulin and α-sitosterol. In addition, the value of the sterol extraction rate during the crystallization procedure is at least 55%.

The value of the recovery rate of sterol from the neutral substance of tall pitch, namely from the starting material used in the method according to this invention, is not less than 45%.

Example 3B

A third batch of material was provided, similar to the first batch after it had gone through two rectification procedures (similar to the data presented in Table 3).

Table 8 provides information on the content of the distillate fraction before recrystallization, as well as a detailed analysis of the chromatogram presented in Fig. 1.

Table 8 : The composition of the distillate fraction before recrystallization, as well as the peak distribution and retention times obtained from FIG. 1.

Composition of the third batch of material (wt.%) ^# Peak ^§ (Fig. 1) Retention time (min) total fatty alcohol content 0.36 - - sitosterol 7.6 6 41.085 campestanol 1.8 4 38.592 campesterol 9.2 3 38.340 β-sitosterol 45.1 5 40.630 Oxysterols 4.3 10 44.509 α-sitosterol 1.3 eleven 46.145 betulin 0.2 12 47.859 stigmastane-3,5-diene 1.0 1 34.331 Δ5-avenasterol 3.6 7 41.213 methyl bethulate 4.3 8 42.361 24-methylcycloartanol 3.2 9 42.645 Total content of certain components 81.96 - -

^§ Peak 2 is the peak of the internal reference, cholesterol (35.599 min)

^# determined during experiments using the GC-FID method.

β-sitosterol crystals were obtained from the third batch of material as described in Example 3A. Table 9 shows the composition of the obtained β-sitosterol crystals.

Table 9 : Crystallization of the distillate fraction after distillation, and peak distribution and retention times obtained from FIG. 2, for the third batch of material

Component Crystalline product (wt.%) ^# Peak ^§ (Fig. 2) Retention time (min) sitosterol 11.5 6 40.884 campestanol 2.0 4 38.467 campesterol 17.7 3 38.190 β-sitosterol 65.1 5 40.629 Oxysterols not detected not detected not detected α-sitosterol not detected not detected not detected betulin not detected not detected not detected stigmastane-3,5-diene 0.04 1 34.229 Δ5-avenasterol 1.2 7 41.032 methyl bethulate 0.2 8 41.846 24-methylcycloartanol 0.3 9 42.360 Total content of certain components 98.04 - - Total content of sterols and stanols 96.30 - -

not found = not found

^§ Peak 2 is the peak of the internal reference, cholesterol (35.456 min)

^# determined during experiments using the GC-FID method.

The total amount of detected components is 98.04% (wt.), as indicated in table 9. The method of the present invention allows you to ensure the content of sterols and stanols in the resulting product at the level of 96.30% (wt.), without any traces of the presence fatty alcohols (solid hydrocarbons).

As can be seen from the results of comparing Figures 1 and 2, peak numbers 10, 11 and 12 have completely disappeared from the chromatogram obtained after sample crystallization. Thus, it was concluded that the extract of phytosterols and stanols, obtained according to the present method, contains less than 0.01% (wt.) each of the following elements: oxysterols, betulin and α-sitosterol.

Claims (31)

1. A method for obtaining an extract of phytosterols and stanols from tall pitch, which includes the following steps, in which a) ensure the presence of tall pitch; b) saponifying tall pitch to obtain saponified tall pitch by adding to the tall pitch a base selected from one or more of NaOH, KOH and CsOH; c) extracting the saponified tall pitch using one or more non-polar aromatic solvents to obtain a solution containing a mixture of neutral substances; d) performing a distillation of a mixture of neutral substances to obtain a distillate fraction and a residual fraction; e) dissolving the distillate fraction in the solvent mixture to obtain a dissolved distillate fraction, characterized in that it comprises a crystallization step (f) which is carried out, when applied to the dissolved distillate fraction under crystallization conditions, to recover the mother liquor and the crystallized fraction, wherein the crystallized fraction forms an extract of phytosterols and stanols, and the solvent mixture used in the step (e) contains from 10% to 60% (w/w) of one or more non-polar solvents, based on the total weight of the solvent mixture; 23 to 40 wt % of one or more solvents having a ketone component, based on the total weight of the solvent mixture; from 2 to 20 wt % of one or more monohydric alcohols, based on the total weight of the solvent mixture; and 0.5 to 2.5 wt % water, based on the total weight of the solvent mixture. 2. The method according to p. 1, characterized in that stage (d) distillation contains one or more sub-stages of distillation, in which d1) performing a first distillation of a mixture of neutral substances to obtain a first distillate fraction and a first residual fraction; d2) performing a second distillation of the first residual fraction to obtain a second distillate fraction and a second residual fraction; d3) if required, perform one or more further distillations of the second residual fraction and further residual fractions, to obtain one or more further distillate fractions and one or more further residual fractions; wherein the distillate fraction dissolved in the solvent mixture in step e) is the second distillate fraction or a mixture of the second distillate fraction with the first distillate fraction and/or at least one further distillate fraction obtained from one or more distillate fractions. 3. The method according to any one of paragraphs. 1 or 2, characterized in that the mixture of solvents used in step (e) contains one or more non-polar solvents selected from pentane, isopentane and/or hexane; preferably, the non-polar solvent is hexane or contains hexane. 4. The method according to p. 1 or 3, characterized in that the mixture of solvents used in step (e) contains one or more solvents having a ketone component selected from acetone and/or methyl ether ketone; preferably, the solvent having a ketone component is acetone or contains acetone. 5. The method according to any one of paragraphs. 1-4, characterized in that the mixture of solvents used in step (e) contains one or more monohydric alcohols selected from methanol, ethanol and/or propanol; preferably, the monohydric alcohol is or contains methanol. 6. The method according to any one of paragraphs. 1-5, characterized in that in step (e) the value of the mass ratio between the solvent mixture and the distillate fraction is from 1.0 to 2.0; preferably, the value of the mass ratio is from 1.1 to 1.7; more preferably, from 1.2 to 1.5. 7. The method according to any one of paragraphs. 1-6, characterized in that the crystallization conditions in step (f) contain a crystallization temperature value ranging from 15°C to 25°C and/or a crystallization time value of at least one hour. 8. The method according to any one of paragraphs. 1-7, characterized in that step (f) further comprises the step of carrying out additional crystallization using a mother liquor to extract additional extract of phytosterols and stanols, while additional crystallization is carried out under the same crystallization conditions as in stage (f); preferably, additional phytosterol and stanol extract is added to the phytosterol and stanol extract extracted in step (f). 9. The method according to any one of paragraphs. 1-8, characterized in that it additionally contains - step (g) washing the extract of phytosterols and stanols using a mixture of solvents used in step (f), at a temperature of from 10°C to 15°C; and/or - an additional step of drying the extract of phytosterols and stanols, preferably at a temperature of at least 100°C for at least 1 hour. 10. The method according to any one of paragraphs. 1-9, characterized in that step (f) is performed, with the content of the distillate fraction: - 2.5% (wt.) or less of α-sitosterol, based on the total weight of the distillate fraction and when determining the specified value using gas chromatography using a flame ionization detector as an analyzer; preferably, 1.7% (wt.) or less α-sitosterol; and/or - at least 20% (wt.) sterols, based on the total weight of the distillate fraction and when determining the specified value using gas chromatography using a flame ionization detector as an analyzer; preferably at least 25% (mass.). 11. The method according to any one of paragraphs. 1-10, characterized in that step (c) extraction of saponified tall pitch using one or more non-polar aromatic solvents is carried out at a temperature value from 80°C to a value at least 10°C lower than the boiling point value of one or more non-polar aromatic solvents. 12. The method according to any one of paragraphs. 1-11, characterized in that one or more non-polar aromatic solvents used in step (c) are selected from toluene and/or xylene; preferably, toluene is used as the non-polar aromatic solvent in step (c). 13. The method according to any one of paragraphs. 2-12, characterized in that stage (d) distillation contains one or more distillation sub-stages, which are one or more stages of distillation carried out using a distillation column; preferably, one or more rectification stages are characterized by the following parameters - the value of the countercurrent coefficient is from 1/1 to 2/1; and/or - the rectification temperature is between 240°C and 280°C, and/or - the distillation column is combined with a countercurrent condenser; preferably, the temperature of the countercurrent condenser is 110°C to 170°C. 14. Extract of phytosterols and stanols, obtained from tall pitch by the method according to any one of paragraphs. 1-13, characterized in that it contains at least 65% (wt.) α-sitosterol, based on the total weight of the extract of phytosterols and stanols, and less than 0.01% (wt.), based on the total weight of the extract of phytosterols and stanols, each of the following components: oxysterols, α-sitosterol and betulin, the content of which is determined during gas chromatography using a flame ionization detector as an analyzer.

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