Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D11/00—Solvent extraction
  • B01D11/04—Solvent extraction of solutions which are liquid
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D11/00—Solvent extraction
  • B01D11/04—Solvent extraction of solutions which are liquid
  • B01D11/0426—Counter-current multistage extraction towers in a vertical or sloping position
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D11/00—Solvent extraction
  • B01D11/04—Solvent extraction of solutions which are liquid
  • B01D11/0476—Moving receptacles, e.g. rotating receptacles

Definitions

• the invention relates to a method according to the preamble of claim 1 and an apparatus for performing this method.
• the DCCC process 200 to 600 thin tubes, which form a coherent vessel system, are filled with a stationary phase, into which the mobile phase continuously introduced in drop form and forced through by means of a pump.
• the mixture of substances to be separated is released in solution in the mobile phase, whereupon the components of the mixture of substances are distributed between the mobile and the stationary phase in accordance with known physical principles in the two-phase system.
• This known method generally allows mixtures to be separated without loss of material.
• the mobile phase is not always distributed in a sufficiently drop-shaped manner in the stationary phase, which can lead to the introduced mobile phase pushing the stationary phase in front of it and pushing it out of the vessel.
• the several hundred individual tubes in the known devices cause equipment problems, in particular sealing problems.
• the object of the invention is to avoid the disadvantages of the known method.
• a method is to be proposed which enables a faster, ie less time-consuming separation of larger than analytical quantities of material in a small number of vessels within a useful period of time.
• the method according to the invention is intended to ensure that the drop-shaped distribution of the mobile phase is maintained in the stationary phase.
• a mixture is to be carried out simultaneously in a single implementation of the method according to the invention on the basis of different
• the properties of the substances are separated into individual substances and / or mixtures of substances, for example a simultaneous separation based on the polarity and structure of the substances.
• the turbulence within the stationary phase causes mixing, which in turn leads to better distribution and separation.
• the droplets striking one another as a result of the turbulence not only experience intensive contact with a corresponding exchange effect, but are also broken down into a number of smaller droplets during the collision, as a result of which the entire exchange-effective surface is greatly enlarged.
• the drops in the mobile phase experience a change in size when passing through the phase interface. -A large drop can burst in. Many small burst or several small drops can combine to form a large one.
• the exchange of substances is intensified by both processes, in particular by the first.
• the turbulent movement of the drops allows the use of vessels with larger diameters, which in turn allows a reduction in the number of vessels and the separation of larger quantities of a mixture of substances.
• the unexpectedly intensive and fast distribution process makes it possible to limit the number of individual tubes or vessels instead of several hundred to a significantly lower number, for example to 10 to 50 or even to a single number, which improves the overview and the reproducibility of the Process greatly increased and at the same time reduced the outlay on equipment.
• the good reproducibility in connection with the relatively short separation time allows the method according to the invention to be used not only in the preparative or analytical laboratory, but also on a procedural scale in production, in particular for the coarse fractionation of extracts.
• the method according to the invention can be used for mixtures of substances from fractions of ml to those in the hl range. It can therefore be used both as a chromatography and as an extraction process.
• three phases are referred to below, although this is only the lowest possible number of phases and higher phase numbers are also possible.
• either two phases in the form of two layers can be arranged next to one another as stationary phases, which are then traversed by a mobile phase, or a stationary phase can be arranged in one vessel, that of two in parallel or in countercurrent guided mobile phases.
• the mobile phase is collected at the end of the vessel where it forms an additional layer so that it acts as an additional stationary phase for another mobile phase. This can further improve distribution / separation.
• This procedure has the further advantage that the ratio of the phases to one another when providing, i.e. Filling, the vessel and in each individual vessel can be done independently of the other vessels in the system. This is practically carried out in such a way that in addition to the actual stationary phase (s), the mobile phase (s) are also introduced in the desired ratio when the vessel is filled.
• a gas phase can also be used as the fourth or further phase, which improves the drop formation and the mixing of the phases and the distribution of the components of the substance mixture in the individual phases in terms of time and quantity. At the same time, it accelerates the separation of the liquid phases before leaving the vessel.
• Inner gases which do not react with the solvents or with the mixture of substances or their components, such as nitrogen, are particularly suitable for this.
• the volume ratio of the stationary to the mobile phases can also be changed from individual vessel to individual vessel as required in the method according to the invention.
• the method according to the invention also enables the mixture of substances to be separated to be introduced into any phase of the phase system.
• This mixture of substances can also be introduced into the stationary phase as a solid or bound to a matrix.
• the device preferably an extractor, for carrying out the method according to the invention has one or more elongated vessels which are connected to one another and have inlet and outlet means at their ends. It is characterized in that the inlet means are formed by changeable nozzles. The diameter, shape and / or number of these nozzles can be changed.
• a collecting area for a mobile phase is arranged at the end of the individual vessel of the device according to the invention.
• a layer-like accumulation of the mobile phase to be discharged is achieved at this point.
• the collecting area can be part of the vessel or a special container that forms a continuation of the vessel. If two phases are carried out in parallel, two collecting areas can be present at the outlet end of the vessel. In the case of two mobile phases guided in countercurrent, a collecting area can be arranged at both ends of the vessel.
• the supply of the one mobile phase can be arranged so that the latter is led directly into the stationary phase or first through the accumulated other mobile phase.
• the individual vessels can have the conventional tubular shape, which can also be bent in a helical or spiral shape, or have a suitable other elongated shape.
• an extractor consists of a single helical tube which is arranged rotatably about the axis of the turning egg.
• the tube can be 5 cm in diameter and the helix can be turned either continuously or periodically and alternately clockwise and counterclockwise.
• FIG. 1 shows an individual vessel for carrying out the method according to the invention
• FIG. 2 shows a vessel system with two stationary and one mobile phase guided from bottom to top
• FIG. 3 shows a vessel system with two stationary and one mobile phase guided from top to bottom;
• FIG. 4 shows a vessel system with a stationary and two mobile phases guided from bottom to top;
• FIG. 5 shows a vessel system with a stationary and two mobile phases guided from top to bottom
• FIG. 6 shows a vessel system with a stationary and a top-to-bottom and a bottom-to-top mobile phase, the two mobile phases being introduced into the same tube; and 7 shows a vessel system with a stationary and a bottom-up and a top-down mobile phase, the mobile phases being introduced at the opposite ends of the system;
• Fig. 8 shows a vascular system of a stationary and a bottom-up and top-down mobile phase, the mobile phases being introduced at the opposite ends of the system as in Fig. 7, but the amount of the individual phases of Vessel to vessel varies and
• Fig. 9 is a vessel system consisting of a single helical tube.
• the tubular vessel 11 in FIG. 1 contains a first mobile phase A introduced through line 12 in the upper part of the vessel and led out of the vessel through line 13 at the bottom, and a second mobile phase A introduced through line 14 into the vessel from below and a second mobile phase C discharged from the vessel through the line 15 at the top.
• a stationary phase B shown in a hatched manner, is arranged in the central region of the vessel 11. The individual phases or layers are separated from one another by interfaces X, Y.
• At the lower end of the vessel there is a collecting area 16 for the mobile phase A and at the upper end of the vessel there is a collecting area 17 for the mobile phase C.
• the mobile phases A and C present in the collecting areas through which the droplets fall ⁇ form introduced mobile phases C and A, act as additional stationary phases.
• the the drops flowing through the respective collected mobile phases burst or disintegrate at the phase boundary X and Y to the stationary phase B into many smaller droplets and are forced through the stationary phase B in zigzag and space curve form.
• the separation of e.g. with the one mobile phase introduced mixture of substances takes place between the respective mobile and stationary phases by mass transfer at the interfaces of the drops and the phase interfaces X and Y.
• the vessel system forming the device consists of five vessels which, in the embodiment shown, are long, straight tubes 1 which are arranged vertically parallel to one another.
• the tubes 1 are connected to one another by lines 2, the diameter d of which is substantially smaller than the diameter D of the tubes 1.
• Inlet means 3 are arranged at one end of the tubes 1 and outlet means 4 are arranged at the other end of the tubes 1, or they can inlet means 3 and outlet means 4 are arranged at both ends of the tubes 1.
• One of the tubes 1 is provided with an additional inlet 5 for introducing the multi-component material system to be separated.
• This inlet 5 is expediently attached to the middle tube 1 or to an outermost tube, preferably in the middle region of the tube.
• the vessels, ie the tubes 1, are filled with two stationary phases A and B and with a mobile phase C.
• the mixture of substances to be separated is introduced into the stationary phase A through the inlet 5 at once.
• the mixture of substances can also be introduced into the other stationary phase B or into the mobile phase C.
• the mobile phase C is continuously introduced from below into the first tube la of the system in the form of drops.
• the mobile phase C moves in the form of drops through the two stationary phases A and B, is collected in the collecting area 17 and leaves the first tube 1 a above through the outlet means 4 and flows through the line 2 into the second tube 1 b of the system back in from below.
• This process is repeated in the other tubes lb, lc, ld, le until the mobile phase C leaves the last tube le.
• the device of FIG. 2 accordingly works in ascending mode.
• the mobile phases are forced in all embodiments in a known manner, e.g. pumped through the stationary phases.
• lower phase B and upper phase C are the stationary phases and phase A is the mobile phase which, introduced above, moves down through the stationary phases B and C, i.e. this device works in descending mode.
• the stationary phase A there is a stationary phase A and two mobile phases B and C.
• the mixture of substances to be separated is introduced into the stationary phase A through the inlet 5.
• the mobile phases B, C are both inserted from below into the first pipe, discharged at its upper end and inserted at the lower end of the following pipe.
• the mobile phases C and B are collected in the collecting areas 16, 17.
• the sequence of the layers of the mobile phases in the collecting areas is determined by the specific weight of the two phase liquids.
• a stationary phase C and two mobile phases B, A are present in the vessel system in FIG. 5.
• the device operates in descending mode, with the two mobile phases A and B moving downward in the form of drops through the stationary phase C.
• FIGS. 1 to 5 can also be referred to as relative countercurrent operation, since the mobile phase or mobile phases are guided through the stationary phase or stationary phases.
• the embodiments according to FIGS. 6, 7, 8 and 9 can also be referred to as absolute countercurrent operation, since here the two mobile phases are carried out in opposite directions.
• This state of equilibrium can be advantageous and desirable for certain processes.
• the exchange process is additionally optimized in the vessel system of FIG. 8 by different amounts of the individual phases per vessel.
• the desired phase ratios are set when the individual vessels are being filled, before the extraction, and remain the same throughout the extraction process. This forms a significant difference from the known methods, where the ratio of the mobile to the stationary phase cannot be freely selected, but rather arises on the basis of the physico-chemical properties of the solvents in the course of the extraction / chromatography.
• the only vessel 11 of the extractor in Fig. 9 consists of a helically bent tube.
• the first mobile phase A is introduced through line 12 from above into the upper part of the vessel 11 and out of the vessel through line 13 below.
• the second mobile phase C is introduced from below into the lower part of the vessel through line 14 and led away from above through line 15.
• the stationary phase B shown with a dot pattern, is arranged in the central region of the vessel 11.
• the vessel alternates periodically around the helix axis, as indicated by the arrow 20 indicated, rotated. As a result, the path length of the upward and downward droplets is additionally lengthened. Otherwise, this system functions like that of FIG. 1.
• the mixture of substances to be separated can be introduced into any tube, preferably approximately in the middle, of the device according to the invention.
• the mixture of substances is expediently introduced into the middle tube or into one of the outer tubes. If a substance mixture bound to a carrier is introduced, 5 collecting agents, e.g. Sieves, arranged for the carrier.
• the mixture of substances to be separated can also be introduced into one of the mobile phases or together with one of the mobile phases in the device.
• the tubes of the vascular system ie the device according to the invention, can be arranged not only in a row as shown in the figures, but also in a circle or in any other configuration.
• the number of tubes or any suitable vessels in the device is, for example, 10 to 50. Extractors with a single tube with a relatively large diameter are preferred.
• the dimensions of the individual tubes are not critical, but the length L (FIG. 6) of the tube is orders of magnitude larger than its diameter D. Suitable ratios L: D are 1: 100 or 1000 or 10,000 . Since the separation distance is one of the essential determining factors for the distribution and therefore for the separation aiming for the greatest possible path length for the mobile phase. This is achieved according to the invention with significantly shorter tube lengths than in the prior art, since the free path length of the mobile phase for a given tube length in the method according to the invention is several orders of magnitude longer than according to the known methods.
• the tubes or other vessels can be arranged vertically or horizontally. They can be stationary or can be rotated in the same or opposite direction about their or any other external axis. The rotatability is particularly useful for spiral and helical vessels.
• the vessels can be made of any internal material, e.g. Glass, quartz glass, quartz or metals. Of course, the vessel material must not react with the phases used or the mixture of substances to be separated.
• the inlet means which are preferably designed as changeable nozzles, are preferably dimensioned such that they produce the smallest possible liquid drops.
• the mobile phase is forced through the stationary phase in a known manner, for example with the aid of a pump.
• the phases depending on the arrangement of the vessels and the apparatus configuration of the device according to the invention, are affected by the gravitational force, the centrifugal force, an additional pressure or vacuum. These forces also cause the mobile phases to separate after they have passed through the stationary phase.
• the preparation of the phases used is according to known processes practical, by which adjusts the phase bil ⁇ Denden intimately liquids, for example by shaking or ultrasonic, mixed "are until a Gleichge ⁇ -equilibrium state, followed by allowing to stand, the individual phases or layers
• the individual phases can consist of a single solvent or of a number of solvents.
• the phases can contain, in addition to the solvents used, other substances which influence their physical or chemical properties
• the composition of individual or several phases can be changed during the ongoing separation process by adding one or more solvents and / or additives or mixtures thereof.
• the temperature in the vessels can be regulated by suitable devices and adapted to the particular requirements.
• the composition of the individual phases can also be changed continuously or periodically.
• the ratio of the individual phases to each other in the ein ⁇ individual vessels can also be "altered as desired.
• a gas can be introduced into the system as a further phase, which promotes the mass transfer and thus the separation and at the same time has a protective function, for example against undesired oxidation.
• the device can be followed by a conventional separation column, for example a chromatography column filled with a solid, and / or a detection device.
• a chloroform extract is produced from 500 g of roots of Peucedanum palustre L. Moench (Apiaceae) dried and pulverized in a suitable manner using a Polytron apparatus (manufacturer: Kinematica, Littau / Lucerne, Switzerland). The extract is evaporated to dryness. 9.2 g of the dry residue is introduced in powder form into the middle limb of an extractor vessel system prepared as described below.
• a 3-phase system is used for the extraction. This is produced by introducing a hexane-acetonitrile-chloroform-water mixture in a volume ratio of 2: 2: 1: 1 into an ultrasound device and sonicating for 15 minutes to ensure the saturation of the phases.
• the extraction vessel system consists of 5 sections or vessels of 1.5 m long tubes with an inner diameter of 1.5 cm.
• the 3 phases are introduced and distributed into the vascular system as shown in FIG. 8. Extraction is carried out on-line in absolute countercurrent for 4.5 hours at a flow rate of 1.2 ml / min in both directions.
• a methanol extract is produced from 200 g of herb of Ruta graveolens L. (Rutaceae) dried and pulverized in a suitable manner by means of a Polytron apparatus (manufacturer: Kinematica Littau / Lucerne, Switzerland).
• the methanol extract concentrated to 15 ml is adsorbed onto glass beads.
• the beads are introduced through the inlet 5 arranged in the middle of the extractor (FIGS. 2-7) into the extractor filled with the desired phases.
• the three phases for the extraction are made from ether, methylene chloride, chloroform, hexane, methanol, acetonitrile, tetrahydrofuran and water in a ratio of 5: 4.5: 27.3: 63.2: 10: 65: '5.8: 19.2 produced by homogenization using ultrasound.
• a helical glass tube (FIG. 9) 4 m long and 1.5 cm inside diameter serves as extractor.
• the extraction is carried out in absolute counterflow according to FIG. 9 with a flow rate of 3 ml / h in both directions.
• the extraction takes 45 minutes, while the helical tube is rotated around the axis of the spiral by 180 ° alternately clockwise and counterclockwise every 20 seconds.
• the coumarin fraction obtained in the upper phase C contains the following substances in significant quantities: Bergapten, Psoralen, Scopoletin, Umbelliferon, Xanthotoxin.
• the main flavonoid component, rutin which is characteristic of this drug, is obtained in an amount of 3.6 g and in a purity of 85%.

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Extraction Or Liquid Replacement (AREA)
• Treatment Of Liquids With Adsorbents In General (AREA)
• Medicines Containing Plant Substances (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=4190786

Family Applications (1)

Country Status (4)

Cited By (1)

Citations (4)

• 1988
  • 1988-02-18 CH CH60288A patent/CH673405A5/de not_active IP Right Cessation
• 1989
  • 1989-02-17 JP JP1501862A patent/JPH02503167A/ja active Pending
  • 1989-02-17 EP EP19890902016 patent/EP0356476A1/de not_active Withdrawn
  • 1989-02-17 WO PCT/CH1989/000028 patent/WO1989007481A1/de not_active Application Discontinuation

Patent Citations (4)

Also Published As

Similar Documents

Legal Events