WO2014121311A1

WO2014121311A1 - Method for enriching valuable substances from a liquid raw material

Info

Publication number: WO2014121311A1
Application number: PCT/AT2014/000006
Authority: WO
Inventors: Eduard Lack; Helmut Seidlitz; Martin Sova; Franz Lang
Original assignee: Natex Prozesstechnologie Gesmbh
Priority date: 2013-02-07
Filing date: 2014-01-14
Publication date: 2014-08-14
Also published as: MX2015010196A; EP2953699A1; AT513907B1; AT513907A1

Abstract

In a method for enriching valuable substances, in particular phytochemicals, such as polyphenols, colorants, antioxidants and similar, from a liquid raw material, such as lipids, fermentation broths or solvent extracts, the raw material is mixed in a mixing device (5) with a compressed extraction agent, in particular CO₂, from a storage container (1), whereupon the mixture is fed to a pre-concentrate separator (13) and the more highly soluble components in the extraction agent are separated from the undissolved components. The charged extraction agent is extracted from the pre-concentrate separator (13) and the undissolved components remain as a pre-concentrate, wherein the charged extraction agent is guided via a separation system, in which the dissolved substances are separated from the charged extraction agent, wherein the purified extraction agent is returned to the storage container (1).

Description

, ^

1

Process for the enrichment of valuable substances from a liquid raw material

The invention relates to a process for the enrichment of valuable substances, in particular phytochemicals, such as e.g. Polyphenoie, dyes, antioxidants and the like, from a liquid raw material, e.g. Lipids, fermentation broths or solvent extracts, as well as an apparatus for carrying out this method.

The enrichment of valuable substances from liquids, such as Lipids are of great importance in both the dye and food industries. The cosmetics industry and the pharmaceutical industry - in particular the sector for the production of so-called "nutraceuticals" - also benefits from the benefits of natural concentrates, colors and aromas.

An example of a lipid-containing lipid is Paprikaole- oresin (also called paprika extract), an extract from the red pepper pulp. It contains, among other things, capsanthin and capsorum, which are responsible for the red color of the pepper fruit. The paprika extract is used in oil- and water-soluble commercial preparations for coloring meat and fish preserves, sweets (marzipan), mayonnaises, sausages and cosmetics. Also as a feed additive for egg yolk and skin pigmentation of poultry fattening, the two dyes are used.

The level of dye concentration in various extracts, such as paprika extract, is commonly measured in Color Units (CU). High values of Color Units, therefore a high concentration of valuable substances, can be found in The industry preferred application, as they have a variety of advantages.

Higher concentrated recyclables have a much higher stability and durability than recyclables with lower concentrations. One of the reasons for this is that higher-concentrated recyclables have a lower oil content than recyclables with lower concentrations and therefore become less easily rancid. In addition, higher concentrations are advantageous because of their easier incorporation into the desired end products. As a further advantage of highly concentrated recyclables may be mentioned their significantly lower weight, which they have compared with unfinished starting materials, resulting in a further advantage for the use of concentrates results - namely, the significantly lower transport costs.

Therefore, a number of processes for the enrichment of valuable substances from liquid raw materials have already been proposed. An example is the multistage, distillative extraction of omega-3 fatty acids from esterified fish oil. Furthermore, it is known, for example, to obtain carotenoid concentrate from algae oil and lycopene concentrate from tomato oil. However, these methods have the disadvantage that the valuable substances are enriched with only low efficiency. Furthermore, a high expenditure on equipment and a high cost to carry out these procedures are necessary. These disadvantages should be avoided. The present invention therefore aims to provide a method and a device which (s) the enrichment of a variety of recyclables from liquid starting materials with low apparati low cost and high efficiency.

To achieve this object, the method according to the invention of the type mentioned initially consists essentially in that the liquid raw material is mixed in a mixing device with a compressed extractant, in particular CO ₂ , from a storage container, whereupon the mixture is fed to a preconcentrate separator and the substances which are predominantly more readily soluble in the extractant are separated from the undissolved constituents which include undissolved valuable substances, the laden extractant being withdrawn from the preconcentrate separator and the undissolved constituents remaining as preconcentrate, the laden extractant being passed through a separator system in which the dissolved substances are separated from the loaded extractant and the purified extractant is returned to the storage container. The extractant is thus used for the extraction of more soluble substances, such as short-chain lipids, so that the less soluble or insoluble substances, such as the long-chain lipid components remain together with the under the prevailing conditions sparingly soluble recyclables.

The economy of the process according to the invention is ensured in particular by the recycling of the extractant. Preferably, the extractant is left in the compressed state during the entire circulation, so that a complete relaxation and subsequent recompression and the associated effort can be avoided. In principle, the enrichment according to the invention can only take place in one stage, so that the abovementioned preconcentrate represents the end product of the process. Preferably, however, it is provided that the enrichment takes place in two stages, the valuable substances with the sparingly soluble constituents of the raw material being concentrated in a first enrichment stage to form a preconcentrate and the preconcentrate being concentrated in a second enrichment stage to form a final concentrate. If necessary, the second enrichment stage is carried out here with changed compared to the first enrichment stage pressure and / or temperature conditions. The two-stage enrichment can be either continuous or discontinuous. Thus, the preconcentrate is either continuously withdrawn from the preconcentrate separator and fed to an extractor connected downstream of the preconcentrate separator, in which it is then further concentrated by renewed supply of extractant from the storage container. The Vorkonzentratabscheider can be designed in this case in the form of a cyclone. Or, according to a further preferred embodiment, the process is further developed such that the preconcentrate in the preconcentrator is enriched further from the storage container to the desired concentration after completion of the feedstock feed with compressed extractant.

As an advantage of the continuous process, it can be seen that the preconcentration of the valuable substances in the preconcentrator and their further concentration in the downstream extractor take place at the same time. Thus, it is not necessary to wait until the loaded extractant has been withdrawn from the preconcentrate separator in order to again feed extractant into the preconcentrate separator - as described in the prior art. continuous process is the case. Parallel to the production of the preconcentrate in the preconcentrator, a renewed feeding of extractant into the downstream extractor and thus the final enrichment of the valuable substances can take place in the continuous process.

The process according to the invention is preferably further developed in such a way that the compressed extractant is present in a liquid or supercritical state in the preconcentrator and optionally in the downstream extractor, by way of example as carbon dioxide. The advantage of the supercritical C0 ₂ over liquid carbon dioxide lies in the fact that the supercritical phase has both a lower viscosity and a lower surface tension than its liquid counterpart. Due to the low viscosity, a high diffusion or through the intensive mixing of the raw material with the supercritical fluid, a rapid mass transfer is achieved. This property thus ensures extraction of substances soluble in the respective extractant from the liquid raw material.

The process according to the invention is preferably developed such that the pressure in the preconcentrator is chosen such that the more easily soluble substances dissolve more strongly in the extractant than the sparingly soluble valuable substance to be enriched. The pressure in Vorkonzentratabscheider or optionally in the downstream extractor is thus adjusted so that the more soluble substances (eg short-chain lipids) solve, while the poorly soluble fraction (eg long-chain lipids, carotenoids, phytochemicals) in undissolved form in Vorkonzentratabscheider or optionally remains in the downstream extractor. In particular, the pressure should be selected such that the valuable material hardly or not solved. The pressure in Vorkonzentratabscheider or optionally in the downstream extractor is hereby preferably selected between 150 and 450 bar. Particularly preferably, the pressure is between 250 to 400 bar.

Advantageously, the method according to the invention is further developed such that the temperature in the preconcentrate separator is selected such that a sufficient difference in density for the separation is achieved. According to the invention the temperature in Vorkonzentratabscheider between 20 and 100 ° C. This achieves a sufficiently low density of the extractant and of the substances dissolved therein, which causes the thus loaded extractant to rise in the preconcentrate separator and can subsequently be withdrawn.

The process according to the invention can be developed in particular to the effect that the separation of the dissolved substances from the loaded extractant is favored by a change in the solubility, in particular a pressure and / or a temperature change.

Advantageously, the separation of the dissolved substances from the loaded extractant in the process according to the invention can also be effected by adsorption or a membrane process.

In particular, it may be envisaged to use tomato oil, hazelnut oil, algae oil, crustacean oil, paprika oleoresin, rice peel oil, coffee oil, fatty acid distillate, fermentation broths or roasted aromatic oil as liquid raw material for subsequent enrichment of the valuable substances contained therein and accordingly lycopene, hazelnut aroma, carotenoids, dyes . Nutraceuticals, coffee flavors, tocopherol or roasted flavors to enrich as concentrated valuable material.

The process according to the invention is advantageously developed in such a way that the final concentrate is discharged via a final concentrate separator in which the extractant remaining in the final concentrate is separated off. This step ensures further separation of the extractant remaining in the stock concentrate, with the result that the end product of the claimed process is in a much purer form than without this last step and that a higher level of extractant can be recycled to the storage container. The apparatus for carrying out the method described above comprises a compressed extractant storage container, a liquid raw material storage container, a mixing device connected to the compressed extractant storage container and the liquid raw material storage container, a separator connected to the mixing apparatus which has a discharge port for discharging a loaded extractant and a discharge port for discharging a preconcentrate, the discharge ports for discharging the loaded extractant being connected to a separator system connected to the compressed extractant storage container through a return line ,

For intensive mixing of the extractant with the liquid raw materials, the inventive construction can be developed such that the mixing device is designed as a static mixer, mixing chamber or nozzle. In order to ensure the extraction of media which are difficult to extract and / or those having a solids content, the formation according to the invention may further preferably be such that the downstream extractor is designed as a thin-layer extractor or as a column extractor. A thin-layer extractor is to be understood as meaning a device as can be taken, for example, from WO 2004/018070 A1. Such a thin-layer extractor has a pressure-resistant reactor with at least one feed opening for the pre-extract and the compressed extraction medium and corresponding discharge openings, wherein the feed opening for the pre-extract to be treated opens on the inner jacket of the reactor, at which a film-like layer of the pre-extract forms , Inside the reactor, a rotor is arranged, the radial arms of which interact with the preconcentrate film on the inner jacket of the reactor. By the use of a reactor, inside which a rotor is arranged, the possibility is created to make the mechanical action by additional action of centrifugal forces, whereby a correspondingly rapid rotation for applying the desired centrifugal force can take place. At the same time, the rotor forms the tools for mechanical processing of the thin film, which in the simplest case of wipers, rollers, doctor blades or the like can be formed. The thickness of the film is determined by the preset distance of the rotating tool to the inner jacket of the reactor. The tools, such as rollers, may have a helical profiling, but may also be conical, concave or convex, the profiling, during unrolling along the preconcentrate film, simultaneously promoting downward movement of the film in the direction of the discharge opening. Countercurrent to the pre ^¬ concentrate the extraction agent is then introduced ^¬ to the reactor, with the corresponding feed opening off the bottom part is formed. The extractant rises inside the reactor and comes into intensive contact with the preconcentrate film, whereby the surface of the film exposed to the extractant is constantly renewed by the kneading process effected by the rotating tools. The loaded extractant may subsequently be withdrawn via an outlet opening provided in the lid.

The device according to the invention is developed in an advantageous manner to the effect that the discharge of the preconcentrator for discharging the preconcentrate with a downstream extractor is in communication and that in the Vorkonzentratabscheider connecting the downstream extractor line another mixing device is arranged with the storage container connected is. This further mixing device allows an additional separation of dissolved in the extractant substances and thus favors the recovery of a final product with very high purity. According to the invention, the device can be designed such that additional extractors are arranged after the previously mentioned extractor for further concentration, the feed in each case being effected via a mixing device in which fresh extractant and correspondingly pre-concentrated mixed material from the respective previous extractor are intensively mixed ,

Advantageously, the device is developed to the effect that the separation system comprises at least two separators, which are connected to each other with the interposition of at least one throttle valve. This ensures that different pressures prevail in the different separators of the system, which are different from the pressure in the preconcentration ratabscheider are chosen lower, which causes the substances dissolved in the extractant can be separated again from the extractant and that the purified extractant can be recycled to the storage container.

The device is preferably designed in such a way that a discharge opening of the preconcentrator or the downstream extractor for discharging the preliminary or final concentrate is connected to a final concentrate separator whose discharge opening for recovering the remaining extractant via a line and a downstream compressor with the Storage tank is connected.

The invention will be explained in more detail with reference to embodiments. In the following process examples, a two-stage enrichment of recyclables is described in each case. In this case, the second enrichment step is carried out after completion of the first enrichment step, so that it is a total of a discontinuous procedure.

Example No.

Step ^ Nr.1

5463 g of paprika oleoresin (30070CU) were injected at a mass flow of 9.2 g / min radially to supercritical C0 ₂ (350 bar, 50 ° C) in a mixing device formed by a pipe. The mass flow of the C0 ₂ was 33kg / h. The mixture of charged C0 ₂ and the undissolved portion of the oleoresin in C0 ₂ was fed to a preconcentrate separator in which the loaded C0 _{2 was separated} from the portion of the oleoresin which was not dissolved in C0 ₂ . The loaded C0 ₂ was further expanded into a separator system. The undissolved part of the oleoresin was accumulated in the preconcentrate separator. profiled. After 600 minutes, ₂ 4211 g of paprika extract (dye value 10035CU) were withdrawn from the preconcentrate separator with the loaded CO ₂ and can be utilized as a by-product. The residue accumulated in the preconcentrate weighed 1252g and had a dye level of 59,700CU.

Step # 2

1252 g of the preconcentrate obtained in step 1 (paprika oleoresin with a color value of 59760CU) were introduced into an extractor. The extractor used in this case may be the preconcentrate separator used in step 1 or a separate aggregate. The preconcentrate was extracted with supercritical CO2 at 33kg / h at 350bar and 50 ° C. After about 150 minutes or 83kg CO? were withdrawn from the extractor with the loaded C0 ₂ 548 g of oleoresin extract (dye value 10420CU). The remaining residue (704 g) in the extractor reached a colorant value of 104000CU.

Example No. 2

Step no

3542 g of paprika oleoresin (30070CU) were injected at a mass flow rate of 9.2 g / min radially into supercritical CO2 (350 bar, 50 ° C) in a mixing device formed by a tube. The mass flow of the C0 ₂ was 33kg / h. The mixture of laden C0 ₂ and the undissolved portion of the oleoresin in C0 ₂ was conducted to a preconcentrator in which the loaded CO _{2 was separated from the} portion of the oleoresin which was not dissolved in CO ₂ . The loaded CO2 was further expanded into a separator system. The undissolved portion of the oleoresin was accumulated in the preconcentrate separator. After 385 minutes, 2505 g of paprika extract (dye value 10060CU) from the preconcentrate were added to the loaded CO2. Ratabscheider deducted and can be recycled as a byproduct. The accumulated in Vorkonzentratabscheider backlog weighed 1037g and had a dye ert of 58852CU. Step # 2

1037 g of the preconcentrate obtained in step 1 (paprika oleoresin with a color value of 59760CU) were introduced into an extractor. The extractor used here can be the preconcentrate separator used in step 1 or a separate aggregate. The preconcentrate was extracted with supercritical CO ₂ at 33 kg / h at 350 bar and 50 ° C. After about 135 minutes and 75kg C0 ₂ ₂ 485g Oleoresinex- were the loaded C0 tract (dye ert 10082CU) withdrawn from the extractor. The remaining residue (552 g) in the extractor reached a colorant value of 105348CU.

The device according to the invention will be explained in more detail with reference to embodiments schematically illustrated in the drawing. 1 shows a device for the batch process according to the present invention, and FIG. 2 shows a device for the continuous process according to the present invention.

In FIG. 1, a storage container for the compressed extraction medium is denoted by 1 and a storage container for the liquid raw material by 2. The storage containers 1 and 2 are connected via the lines 3 and 4 with the mixing device 5. In line 3, the extractant is compressed by the use of the motor-driven pump 7 and thereby brought to the desired pressure level. To avoid cavitation in pump 7 either a pre-pressure pump 6 or a pre-cooler in line 3 is installed. In addition, the heat exchanger 8 brings the compressed extractant to the desired temperature. temperature. Similarly, the heat exchanger 9, which is located in line 4, provides for adjusting the temperature of the liquid raw materials. The flow of the compressed extractant and the liquid raw materials can be controlled by means of speed regulators on the pumps 7 and 12. Since the solution process is dependent on the amount of extractant, the ratio of liquid raw material to volume flow of the extractant influences the extraction performance and can be set individually by the speed controls of the pumps 7 and 12. The guided through the shut-off valve 10 liquid raw material is fed by means of the downstream pump 12 in the mixing device 5, while the compressed extractant reaches the mixing device 5 via line 3. In the mixing device 5, which is preferably designed as a static mixer, the two components are mixed intensively. This results in a disperse mixture of extractant and liquid raw material. This mixture is withdrawn from the mixing device 5 and spent in the Vorkonzentratabscheider 13. In pre-concentrate separator 13, for example, there is a pressure of 350 bar at a temperature of, for example, 50.degree. In this case, the more readily soluble components such as the short-chain lipids are present in dissolved form in the extractant, while the fraction of poorly soluble components such as the long-chain lipids and the valuable substances are undissolved in the preconcentrate separator 13. The density difference of the two fractions leads to the formation of two phases - in the extractant, the more readily soluble components such as short-chain lipids as the first phase and undissolved sparingly soluble components such as long-chain lipids and recyclables as the second phase. The first of the above-described loaded phases subsequently rises due to their clotting ^¬ cal density upwards and is withdrawn there via the discharge opening 14. The selected pressure and temperature level ensures makes a sufficient density difference between the two phases. In Vorkonzentratabscheider 13, a corresponding distribution system is installed. The Austragsöff sion 14 is connected via the line 15 with a separator system, which consists of two preconcentrator downstream of the precipitators 16 and 17. The line 15 further has a throttle valve 18 which controls the extractant flow as needed. The respective pressure level in the downstream separators 16 and 17 is gradually reduced, the separator 16 having an internal pressure of for example 90-120 bar and the separator 17 having an internal pressure of, for example, only 40-60 bar. The two separators 16 and 17 are connected to one another via the line 19, wherein the pressure of the loaded extractant in separator 16 is regulated by a further throttle valve 20 and an increase of the temperature and / or an evaporation of the extractant is achieved via the heat exchanger 21 , By means of the control valves 24 and 25, the sparingly soluble components such as triglycerides and recyclables separated by the extractant can be withdrawn via the lines 22 and 23, the now unloaded extractant being fed again to the storage container 1 via line 35 and with the interposition of a condenser 27. The storage tank 1 reached extractant thus has at this time already back at the right temperature and the right pressure to become again the procedure applied ^¬ leads. In order to enrich the desired valuable substances, the unresolved fraction of valuable substances (the preconcentrate) remaining after discharge of the feed of liquid raw material into the preconcentrate separator 13 is removed via the discharge opening 26. gene - or optionally brought by renewed supply of compressed extractant from line 3 to the desired concentration. The concentrate thus obtained is thus introduced into the line 28 and reaches the final concentrate separator 29, from which the final concentrate is subsequently transported via the discharge opening 30 in line 31, wherein the withdrawal can be controlled via a control valve 32. The pressure in Endkonzentratabscheider 29 is adjusted by means of a control valve 50.

In the discontinuous process there is thus a pressure difference between the pre-concentrate separator 13 and the final concentrate separator 29, whereby it is possible to extract the liberated extractant via the further discharge opening 33 and return it into the storage container 1 via the line 35 and the condenser 27 with the aid of the motor-driven compressor 34.

2 describes the continuous course of the process according to the invention. The steps carried out essentially correspond to those of the batch process (see Fig.l). However, in addition to the method described in FIG. 1, the continuous process includes a further line 36, in which the extraction agent is compressed by the use of the motor-driven pump 38 and brought to the desired pressure level. To avoid cavitation in pump 38 either a pre-pressure pump 37 or a pre-cooler in line 36 is installed. Furthermore, the heat exchanger 39 ensures that the compressed extractant to bring to the desired temperature.

In addition, the continuous process includes an extractor 40 and downstream of the preconcentrator 13 another arranged between Vorkonzentratabscheider 13 and the downstream extractor 40 mixing device 41. The withdrawn from the Vorkonzentratabscheider 13 via line 28 amount can be controlled by a level measurement in Vorkonzentratabschei- 13 and / or a corresponding pump 51. The discharge opening 26 together with line 28 and the line 36 open into the mixing device 41, where a renewed intensive mixing of the withdrawn from the Vorkonzentratabscheider 13 preconcentrate and the extraction agent from line 36 takes place. The mixture thus obtained is fed in the sequence in the downstream extractor 40. Thus, for example, 350 bar, or, depending on solubility of the components to be removed additionally a predominantly increased pressure - in nachge ^¬ switched extractor 40 is either the same pressure as in the upstream Vorkonzentratabscheider 13 prevails. The less soluble components thus dissolve in the extractant while the fraction of recyclables and higher polar components remain undissolved in the downstream extractor 40. The density difference of the two fractions leads, as already described above, to the formation of two phases. The first phase loaded with the additional components to be removed increases and is withdrawn via the further discharge opening 49 from the downstream extractor 40. In order to obtain the concentrate of desired recyclables, the remaining in the downstream extractor 40 unresolved fraction of recyclables and higher polar components is withdrawn via the discharge port 42 and spent in the line 43, this can be regulated again via a throttle valve 44 and then reaches the Endkonzentratabscheider 45, which with eg 10 bar internal pressure has a substantially lower pressure than the extractor 40. The final concentrate is withdrawn via line 46 from the Endkonzentratabscheider 45, wherein this is again regulated via a throttle valve 47, while any remaining amount of extractant is returned via the discharge opening 48 in the storage container 1.

Claims

claims:

1. A process for the enrichment of valuable substances, in particular phytochemicals, such as polyphenols, dyes, antioxidants and the like, from a liquid raw material, such as lipids, fermentation broths or solvent extracts, characterized in that the raw material in a mixing device (5) with a compressed extractant, in particular CÖ2 _t from a storage container (1), whereupon the mixture is fed to a Vorkonzentratabscheider (13) and the extractant in the more highly soluble components of the undissolved constituents, which include the undissolved recyclables are separated, wherein the loaded extractant is withdrawn from the Vorkonzentratabscheider (13) and the undissolved constituents remain as preconcentrate, wherein the loaded extractant through a separator system, is guided, in which the dissolved substances are separated from the charged extractant, wherein the purified Extrak tion medium is returned to the storage container (1).

2. The method according to claim 1, characterized in that the preconcentrate is continuously withdrawn from the Vorkonzentratabscheider (13) and fed to the Vorkonzentratabscheider (13) downstream extractor (40), in which it under feeding of extractant from the storage container (1) on is concentrated to obtain a final concentrate.

3. The method according to claim 1, characterized in that the preconcentrate in Vorkonzentratabscheider (13) after completion of the raw material feed with compressed extractant from the Speicherbehäiter (1) is further enriched to the desired concentration to obtain a final concentrate.

4. The method according to any one of claims 1 to 3, characterized in that the mixing device (5,41) is designed as a static mixer, mixing chamber or nozzle.

5. The method according to any one of claims 1 to 4, characterized in that the compressed extractant in liquid or supercritical state in Vorkonzentratabscheider (13) and optionally in the downstream extractor (40) is present.

6. The method according to any one of claims 1 to 5, characterized in that the pressure in Vorkonzentratabscheider (13) is selected such that the more soluble components in the extractant solve more than the valuable material to be enriched, the pressure 150 to 450 bar, in particular 250 to 400 bar.

7. The method according to any one of claims 1 to 6, characterized in that the temperature in Vorkonzentratabscheider (13) is selected such that sufficient for the separation density difference is achieved, wherein the temperature is between 20 and 100 ° C.

8. The method according to any one of claims 2 to 7, characterized in that the downstream extractor (40) is designed as a thin-layer extractor or as a column extractor.

9. The method according to any one of claims 1 to 8, characterized in that a plurality of the Vorkonzentratabscheider (13) downstream extractors is provided, which are arranged in series, each extractor of the preceding in the row each extractor and fresh extractant fed becomes.

10. The method according to claim 9, characterized in that the extraction is carried out in the downstream or the extractor (s) with changed compared to the preceding extractor pressure and / or temperature conditions.

11. The method according to any one of claims 1 to 10, characterized in that the separation of the dissolved substances from the loaded extractant a change in solubility, in particular a pressure and / or a temperature change, summarized.

12. The method according to any one of claims 1 to 10, characterized in that the separation of the dissolved substances from the loaded extractant comprises an adsorption or a membrane process.

13. The method according to any one of claims 1 to 12, characterized in that as a raw material tomato oil, hazelnut oil, alge- oil, crustacean oil, paprika oleoresin, rice shell oil, coffee oil, fatty acid distillate or roasted aromatic oil is used.

14. The method according to any one of claims 1 to 13, characterized in that are selected as valuable lycopene, hazelnut flavoring, carotenoids, dyes, Nutraceuticals, coffee flavors, tocopherol or toasted flavors.

15. The method according to any one of claims 1 to 14, characterized in that the final concentrate via a Endkonzent- ratabscheider (29,45) is discharged, is separated in the remaining in the final concentrate extractant.

16. A device for carrying out the method according to any one of claims 1 to 15, comprising a storage container (1) for a compressed extractant, a storage container (2) for liquid raw material, a mixing device (5) to the storage container (1) for the compressed extractant and connected to the liquid raw material storage tank (2), a pre-concentrate separator (13) connected to the mixing device (5), a discharge opening (14) for discharging a loaded extractant and a discharge opening (26) for discharging a Preconcentrate, wherein the discharge openings (14) for discharging the loaded extractant is connected to a separator system which is connected via a return line (35) to the storage vessel (1) for the compressed extractant.

17. An apparatus for carrying out the method according to claim 16, characterized in that the discharge opening (26) for discharging the preconcentrate with a downstream extractor (40) is in communication and in the Vorkonzentratabscheider (13) with the downstream extractor (40) connecting Line (28) a further mixing device (41) is arranged, which is connected via a further line (36) with the storage container (1).

18. Device according to one of claims 16 or 17, characterized in that the separator system comprises at least two separators (16,17) which are interconnected with the interposition of at least one throttle valve (20).

19. Device according to one of claims 16 to 18, characterized in that a discharge opening (26, 42) of the preconcentrate separator (13) or of the downstream extractor (40) for dispensing the preliminary or final concentrate with a final condenser Zentratabscheider (29,45) is connected, the discharge opening (33,48) for discharging the remaining extractant via a line (35) and a downstream compressor (34) to the storage container (1) is connected.