BG109918A - Multifunctional appliance for extracting substances from plant materials - Google Patents

Abstract

The multifunctional appliance for extracting substances from plant raw materials represents a device used to perform a number of operations, such as extraction(s), separation, filtration, drying, and water vapour distillation. It is used for obtaining a variety of extracts, including nutritional supplements, antioxidants, biostimulators, dyes, etc., from medicinal and other plants for the pharmaceutical, cosmetic, food and other industries. The construction of the apparatus allows various operations to be conducted in one device, with high efficiency in terms of degree of extraction of the substances, degree of separation of the phases, and reduction of the amount of the solvents used. The appliance consists of two coaxial cylinders: a stationary outer cylinder (1) equipped with input / output openings for the plant mass and the fluids, and an inner mobile cylinder (2). The cylinders are arranged horizontally, the inner cylinder rotates with a different peripheral speed from 15 cm.s-1to 25 m.s-1, continuously or periodically with a constant or changing direction of rotation, and there is a perforated surrounding wall, along which at the inside there are longitudinal partitions, either dense or perforated, which separate the cylinder into sectors, where containers of filtering material for the plant raw material are placed.

Description

Technical field

The invention relates to a multifunctional apparatus for extracting substances from plant materials. The apparatus is used for the preparation of active ingredients used in the pharmaceutical, cosmetic and food industries.

BACKGROUND OF THE INVENTION

Solid-liquid extraction is one of the most commonly used operations for extracting valuable ingredients from roots, leaves, seeds, flowers and more. parts of plants. It is effected by contacting the plant feedstock with a suitable liquid (extractant) that extracts predominantly the desired components from the feedstock. The resulting solution (extract) contains other ingredients, but the content of the valuable components in the extract is much higher than in the raw material of the plant, due to the low solubility of most of the other ingredients. The obtained plant extracts are used directly or after further purification for the needs of the pharmaceutical, cosmetic and food industries. Depending on the target components, different extractants are used to extract them - solvents or solutions containing the active components.

Various designs of apparatus for solid-liquid extraction of plant material substances are known. For this operation, containers with movable or fixed grilles or perforated baskets in which the raw material is placed are often used. The latter is flooded with liquid and the resulting solution drained under the grid [1-4]. For a more complete recovery of the valuable ingredients, the solution usually passes repeatedly through the plant material. Soxhlet type extractors are widely used, in which the resulting vegetable extract is subjected to distillation to remove the solvent, which is then re-contacted with the raw material, allowing complete extraction of valuable components [5-8]. Vertical and horizontal augers are also used. · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · Extractors, apparatus with mechanical, pneumatic or mixed stirring, pulsating columns, etc. [9-14]. A common problem with existing extractor structures is the need to further separate the spent plant material from the solution (solvent) after the extraction process, which is usually performed in another apparatus. For this purpose, compression, centrifugation or evaporation are used, with the latter separating the solvent (eg ethanol) from the spent material by water vapor treatment. Apparatus designs are also known in which the solution obtained after extraction is partially separated from the spent material by draining [15]. For its complete elimination

additional drying of the vegetable mass in the same apparatus is suggested, which is however only appropriate provided that the extract containing the valuable substances is already completely removed from the apparatus and the humidity of the spent raw material is due solely to residues from the pure solvent after performing the washing.

Technical nature

The invention is a multifunctional apparatus consisting of two horizontal coaxially arranged cylinders, an external solid fixed with fluid inlets and outlets, and an internal perforated cylinder which can rotate about its longitudinal axis with variable speed and inward direction, inwardly to which cylinders are attached symmetrically and radially arranged bulkheads, dense or perforated, between which bulkheads there are filter sleeves - containers for plant mass.

STAFF DESCRIPTION OF THE APPARATUS

The apparatus consists of two horizontal coaxially arranged cylinders, (Fig. 1):

External (1), which is stationary and equipped with nozzles - for the inlet or outlet of fluids - one in its lowest part (9) and the other (other) (3) in the highest located part, as and one hermetically sealed opening (4) for refilling with fresh vegetable material and respectively removing the spent material from the apparatus. Liquid or gaseous fluids may also be introduced into the apparatus through

fixed perforated hollow shaft (5) located on the axis of the inner cylinder (2) ·

The inner cylinder (2) is perforated on its lateral surface and can be rotated periodically or continuously at a peripheral speed varying widely - from 15 cm.s ' ¹ to 25 m.s' ¹ , as well as changing the direction of rotation. Perpendicularly, three or more symmetrically and radially arranged uniform or perforated bulkheads (6) are attached to the inner wall of this cylinder and along its entire length. In the sectors formed by the perforated inner cylinder (2) and the aforementioned barriers, there are contained filter sleeves - containers (7) of shape and volume corresponding to the shape and volume of those sectors made of filter material. In the process, the containers are tightly closed and contain approximately equal amounts of finely ground vegetable mass.

The rotating cylinder is driven by an electric motor suitable for operation under the appropriate conditions and in the said wide range of rotational speeds.

The lower opening (9) of the fixed cylinder (1) is connected to a pump by means of which the extracts or other solutions obtained are discharged to the different purpose tanks, depending on the extraction scheme and the arrangement of the flows described in the following section, including for flushing and draining the extractor.

The upper opening (s) - nozzle (s) (3) of the outer cylinder (I) are intended for introducing solutions into the apparatus under certain operating modes or for removing vapors and gases released during the process.

The operation of the apparatus is carried out in cooperation with a number of other apparatus, devices and control devices, such as tanks, filters, heaters, evaporators, heat exchangers, pumps, meters, controllers, etc.

FUNCTIONING OF THE APPARATUS

The device allows to realize several types of operating modes, through the combination of which can be carried out a large number of different extraction schemes, including single, multiple or multi-stage extraction, can be applied countercurrent extraction, cross current extraction, percolation, differential extraction, steam distillation, • «· · · ·

extraction using a variable composition extractant, extraction with two or more solvents, combinations of extraction, washing and drying, and the like.

Most extraction schemes apply the so-called. "Dip and drain" mode, in which the raw material in the mentioned sectors is periodically contacted with the liquid and then drained. After charging the apparatus with a solid phase, the liquid phase is introduced into it in quantity, composition and temperature according to

provided for by the applied extraction scheme, and the inner cylinder is rotated at low angular speed. Typically, the volume of this fluid is 2-4 times the volume of the solid phase. When the cylinder rotates at a low speed, this fluid consistently moistens a portion of the solid phase located in the lowest positioned sectors, and then, as a result of the rotation of the cylinder, it passes through the raw material, drains from it, and re-collects at the bottom of the the cylinder. The dip and drain mode is characterized by the fact that the liquid phase preferably does not pass through the perforations of the rotary

is a cylinder except for the part of it that is immersed in the fluid layer.

When operating in percolation mode, the liquid phase is fed into the apparatus continuously through the central stationary perforated shaft (5), and the inner cylinder (2), charged with plant material, rotates at moderately high revolutions. Under the action of centrifugal forces, the fluid passes through the material (7) and through the perforation of the inner rotating cylinder (2) enters the outer cylinder (1), from which it is drawn out through a nozzle (9) and returned to the apparatus by means of a pump. the central shaft (5). The percolation mode is carried out at moderately high rotational speeds of the inner cylinder, selected in such a way as to allow the fluid to flow freely through the material and at the same time to retain a sufficient amount of fluid in it. The speed of the fluid flow through the drug and the contact time between the phases are regulated by the rotational speed. Repeated flow of liquid (repeated contact) over a unit of time can be performed. the duration of the process is shortened.

For complete removal of the liquid phase from the extractable material, the apparatus is brought into centrifugation mode. For this purpose, the rotation speed of the inner cylinder is increased, while at the same time the separated liquid is pumped from the outer cylinder through the nozzle (9).

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A more complete recovery of the extractable components is achieved by continuous regeneration of the solvent by a suitable parallel separation process, e.g. liquid-liquid extraction, membrane separation or evaporation and condensation of the solvent, precipitation of said components by changing the temperature or changing the pH of the liquid phase), whereby a fresh solvent with a greater extraction capacity is constantly introduced into the apparatus.

When using an extractant whose presence in the depleted material is undesirable for economic or environmental reasons, before removal from the extractor, the material is flushed with another suitable solvent (eg water) and the resulting liquid mixture is collected in another container for further processing.

The same is done when using instead of the flushing liquid of water or other steam or inert gas introduced through the central perforated shaft at low or moderately high rotation speeds of the inner cylinder of the extractor.

Similarly, drying of hot gas (air) material inside the apparatus can be carried out. The removed liquid or gaseous phases are suitably treated for the recovery of the solvent removed.

In multistage or combined extraction schemes, the material liberated from the liquid phase is treated with the next successive portion of the liquid phase according to the chosen scheme, or if this is the last contact of the solid phase with a solution (solvent), the material is removed from the sectors and deposited if not subject to any other processing before.

One of the most complex schemes implemented with this apparatus is multiple counter current extraction with partial or complete removal of the solvent. In this scheme, one of the peripheral inputs (3) for the liquid phase is connected via a collector to a series of N number of liquid phase tanks. The number of tanks N is determined by the number of contacts of the raw material with the solvent needed to achieve the desired recovery rate. When a fluid is applied, it is introduced from this tank into the apparatus for the first extraction of newly loaded plant mass. Dip and drain mode is implemented according to the technological prescription. The resulting extract, the scheme, gradually increases the concentration of the solution in the tanks over time, with the Nth tank containing fresh solvent and the tank No. having the highest concentration of the extracted substance. Required amount »· · • · ·

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9 99 including portions separated by centrifugation of the material is displayed as a production solution. The required amount of liquid from tank No. 2 is introduced into the extractor and proceeded in an analogous manner, with the resulting second extract entering tank No. 1. Following is a new treatment of the material with solution from tank No. 3 and transferring the resulting third extract to tank No. 2. The procedure is repeated until the last operation using a pure extractant contained in tank No. N, after which the spent material is treated in some of the ways described above or removed from the extractor. This is followed by a recharge of the plant material and a repeat of the cycle.

The multifunctional device offered has the following advantages over the known apparatus:

1 / Allows multiple operations to be performed in one unit.

2 / Provides improved contact with the raw material and reduces the amount of extractant required.

3 / Creates conditions for intensified contact mode in comparison with known devices.

4 / Enables a variety of contact circuits to be reproduced in a single apparatus that reproduce those performed in columnar or multi-body installations.

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Description of the figure

Figure 1 is a diagram of an apparatus for extracting substances from vegetable raw materials, consisting of two horizontal coaxially arranged cylinders. The outer cylinder (1) is stationary, while the perforated inner cylinder (2) can rotate at a variable speed and change its direction of rotation. The outer cylinder (1) is provided with two or more tube nozzles one in its lowest part (9) and the other (other) (3) in the highest part, as well as one hermetically sealed opening (4) for the introduction of fresh plant material and respectively the removal of the spent material from the apparatus. The perforated hollow shaft (5) is located on the cylinder axis and gives • 9

9 9 9 · ♦ possibility of introducing liquid or gaseous fluids into the apparatus. Perpendicularly, to the inner wall of the inner cylinder (2) and along its entire length are fixed symmetrically and radially spaced barriers (6) whose height is not greater than half the radius of the cylinder. The sectors formed by the perforated inner cylinder (2) and the baffles (6) contain filter sleeves - containers (7) containing pulverized vegetable mass. The free fluid (8) occupies a small segment of the cross section of the inner cylinder.

Examples of implementation

The efficiency of the proposed apparatus for extracting active components from plant materials is illustrated by the following examples:

EXAMPLE 1

Double countercurrent extraction. 1200 g of finely ground dry willow bark (1-2 mm fraction) of Salix Alba L. are distributed 200 g in six containers of filter cloth. The well-sealed containers are placed in the six sections of the inner perforated cylinder of the extractor with a diameter of 320 mm and a length of 300 mm. The extraction was performed with 6.0 L of liquid (extract) obtained from the second extraction of a previous portion of the herb at 60 ° C for 30 min in dip and drain mode and an internal cylinder rotation speed of 15 rpm. After the extraction is complete, the extract is withdrawn and the rpm rises to 1360 rpm for 5 min to remove any residual fluid. The combined extract with a total volume of 5.1 L was dried. The material liberated from the bulk is subjected to a second extraction with 5.2 L of pure water at 60 ° C under the same conditions as the first extraction. After removal of the second extract in the manner described above, the latter is used to carry out the first extraction of the next portion of fresh herb. A double-extracted herb weighing 2120 g is deposited. From the said 5.1 L liquid extract, after drying, 235 g of dry extract containing 18% salicin are obtained, representing 93% of the raw material content.

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EXAMPLE 2

Triple countercurrent extraction. Multiple countercurrent extraction scheme was carried out, in which case the number of collectors is 3. 720 g finely ground dry leaves of Vinca minor L. containing 0.021% (HPLC analysis) of Vincamine, evenly distributed in the six sectors of the extractor mentioned in EXAMPLE 1 was sequentially extracted at 50 ° C initially with the extract obtained from the second extraction of a previous portion of the herb, then with that of the first extraction of a previous portion of the herb and

a third time with a fresh solvent representing an aqueous acetic acid solution of pH = 4. As in Example 1, after each extraction, the liquid was removed by centrifugation for 5 min at 1360 rpm and then transferred to the appropriate tank. Extraction in all three operations is performed in dip and drain mode for 25 minutes at an internal cylinder rotation speed of 15 rpm. After the latter (third in relation to the specific portion of the raw material) extraction and centrifugation, the spent raw material with a humidity of about 50% and a content of vincamine below 0.0005% is deposited. Evaporation to dryness of the final extract afforded 155 g of a product containing 0.094% vincamine. If the final extract is not concentrated and dried but basified and subjected to repeated extraction with trichlorethylene, an extract is obtained from which, after evaporation of the organic solvent and drying, 2.70 g of enriched product is obtained, which contains 5.14% vincamine and can be directly used in pharmaceutical manufacturing.

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EXAMPLE 3 Multiple (Triple) Cross-Current Extraction. 860 g of ground milkweed (Melissa officinalis L.), 0.25-0.71 mm fraction containing 24.8 g of rosemary acid were distributed evenly in the six sectors of the extractor mentioned in EXAMPLE 1. The herb is extracted three times with 6.0, 5.0 and 5.0 L of pure water at 70 ° C, respectively. The duration of each extraction in dip and drain mode is 15 minutes at a cylinder speed of 15 rpm. After each extraction, the extract obtained is removed by centrifugation for 5 minutes, increasing the revolutions of the perforated cylinder by 250 up to 1360 rpm. The following table shows the concentrations of rosemary acid in each of the three extracts, as well as the contribution of each of the operations.

Extraction The amount of extract Rosmaric acid Quantity extracted No L gL ¹ % 1 4.9 3.12 61.69 2 5.0 1.22 24.60 3 5.2 0.36 7.66 total 15.1 1.54 93.95

Evaporation to dryness of the combined extract gave 141 g of dry product containing 16.5% rosemary acid.

EXAMPLE 4

Percolation extraction. 1020 g of ground beetroot powder (Atropa belladonna L.), 0.4-2.0 mm fraction, uniformly distributed in six containers and placed in the six sectors of the extractor described in EXAMPLE 1, are extracted in percolation with a slightly alkaline aqueous solution ( pH = 9.5) at 25 ° C for 3 h. For this purpose, an extractant with a flow rate of 180 L.h ' ¹ is periodically fed through the central perforated shaft for 3 s, followed by a period of 27 s without fluid delivery. The average flow rate is 18 L.h ' ¹ . The total duration of one cycle is 30 s. The extractor internal cylinder rotates continuously at 190 rpm. The liquid extract obtained in the apparatus is withdrawn from it and subjected to in-situ perturbation in another apparatus to release the extracted tropane alkaloids by recycling between the two apparatus. Diisopropyl ether is used as the liquid membrane during the pertraction and 0.01 n H2SO4 as the receiving solution. Perpraction tropone alkaloids are purified and concentrated in the receiving solution. Upon completion of the process (3 h) and evaporation to dryness of the solution, 5.2 g of product containing 72% of tropic alkaloids calculated on the basis of atropine were obtained.

EXAMPLE 5

Combined steam distillation and extraction. 1180 g of ground thyme leaves (Thymus vulgaris L.), 2-3 mm fraction, evenly distributed in six containers and placed in the six sectors of the extractor described in EXAMPLE 1, whose internal perforated cylinder rotates at a rate • * · · · · · · · ·

190 rpm, steamed with water. The vapor is introduced through a central perforated shaft with a flow rate of 3 kg.h ' ¹ and a temperature of 100 ° C. The outlet (3) of the extractor is connected to a steam condenser heat exchanger and the latter to a laboratory separator of water-oily mixtures of type "Florentine vessel" with a volume of 0.7 L. After a 3-hour steaming of the drug, about 7.0 L of distillation water is obtained. containing 14.2 mL of essential oil, representing 62% of the dry drug contained in the drug. The evaporated drug, after partial cooling, was extracted twice with 6.0 and 5.0 L of 70% ethanol at 50 ° C, respectively. The duration of each dip and drain extraction is 15 min. After each extraction, the resulting liquid was removed by centrifugation for 5 min at 1360 rpm. The extraction resulted in a 12.1 L extract having an ethanol content of 62% (vol.). Removal in vacuo of ethanol and water gave 137 g of oleoresin containing 4.5% flavonoids, defined as hyperoside.

EXAMPLE 6

Combined extraction with two immiscible extractants. 1480 g of dried and ground dried wild chestnut fruits (Aesculus Hyppocastanum L.), evenly distributed in six containers in the extractor described in EXAMPLE 1, were extracted twice with 6.0 L normal hexane in “dip and drain” mode for 35 minutes at 25 ° C and a cylinder speed of 15 rpm. The two extracts obtained are collected and after removal of the hexane by evaporation, this extract yields 75 g of an oily product containing fatty oil and other oil-soluble components of the raw material. The degreased centrifuged material is washed once with 6 L of hot (90 ° C) water and re-centrifuged. The treated plant mass was then extracted twice each 30 min according to the counterflow scheme described in EXAMPLE 1 with a 7.0 L 70% aqueous ethyl alcohol solution at 70 ° C. . The extract obtained after draining and centrifuging is concentrated and evaporated in vacuo to dryness. A product was obtained containing 23% triterpene saponins defined as escin.

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Application (use) of the invention

The invention can be widely used for the extraction of useful components, such as biologically active substances (vitamins, amino acids, alkaloids, flavonoids, glycosides, saponins, organic acids, etc.), natural and synthetic dyes, flavors, etc., contained in various plant sources, which are valuable raw materials for various purposes in the pharmaceutical, cosmetic, food, etc. industry

Literature

1. US5707673

2. US5676991

3. US4258011

4. E.J. Bernardini, J. Am. OilChem. Soc., 53 (1976) 275.

5. US6849279

6. US5776317

Ί. US5017500

8. US4157984

9. US4617177

10. Ρ0144038

11. US4490335

12. RU2225242

13. GB2015893

14. ΡΡ0583200

15. EPO197872

Claims (2)

Patent Claims A multifunctional apparatus for the extraction of substances from vegetable raw materials, consisting of two coaxial cylinders; external fixed (1) and provided with inlets and outlets for the plant mass and the corresponding fluids, and internal movable (2), characterized in that the cylinders are arranged horizontally, the inner cylinder (2) rotates at a different peripheral speed of 15 cm .s ' ¹ to 25 ms' ¹ , continuous or intermittent at a constant or varying direction of rotation, and having a perforated surrounding wall along which there are longitudinal partitions, dense or perforated on the inside, which divide the cylinder into sectors, in which are located container and from the filter material for the raw material. A multifunctional plant material extraction apparatus according to claim 1, characterized in that a coaxially hollow fixed shaft (5) perforated in the part inside the inner cylinder is housed on the axis of the inner cylinder (2).