Chromatography system

Abstract

The invention relates to a chromatography system comprising a first pump which is / can be connected to a fluid reservoir for a first fluid, and a second pump which is / can be connected to a fluid reservoir for a second fluid, wherein the pump outlet lines of the first pump and of the second pump are connected to a connecting piece, and a chromatography column is provided downstream of said connecting piece when viewed in the flow direction, and an injection unit is provided upstream of the chromatography column when viewed in the flow direction, wherein the injection unit comprises a sample loop and an injection valve, wherein the injection valve has at least two sample loop ports and two high-pressure ports for the supply and discharge of highly pressurised fluid, as well as two sample loading ports for loading the sample loop.

Description

[0001] Chromatography system

[0002] The present invention relates to a chromatography system and a chromatography process.

[0003] Chromatographic techniques are important tools for identifying and separating complex samples. The fundamental principle underlying chromatographic techniques is the separation of a mixture into its individual components by transporting the mixture in a moving fluid through a retentive medium. The moving fluid is typically referred to as the mobile phase, and the retentive medium is typically referred to as the stationary phase. The separation of the different constituents of the mixture is based on their differing distributions between the mobile and stationary phases. Differences in the partition coefficients of the components lead to different retention rates at the stationary phase, resulting in separation.

[0004] Advanced and now well-established chromatography methods include high-performance liquid chromatography (HPLC) and supercritical fluid chromatography (SFC).

[0005] Properly applying the sample to the chromatography column is an essential step for all techniques, but especially for HPLC and SFC, to achieve good and reliable separation.

[0006] In HPLC, a sample to be analyzed must be fed into a high-pressure liquid stream, with interruptions to this stream being kept to a minimum. High-pressure injection valves are used for this purpose, enabling virtually seamless switching of the liquid stream. This issue is described in detail, for example, in German patent application DE10 2008 006 266 A1 and the publications cited therein.

[0007] Supercritical fluid chromatography (SFC) offers numerous advantages, enabling the simple and reliable separation, chemical analysis, identification, and quantification of various substances. When using carbon dioxide (CO2) as the liquid in SFC applications, substance extraction generally occurs above the critical temperature of 31°C. 0 C and above a critical pressure of 74 bar.

[0008] To keep CO2 or a CO2 mixture in a liquid state within a chromatography column, the entire chromatography system must be maintained at a predetermined pressure level. For this purpose, a backpressure regulator is typically provided downstream of the chromatography column and downstream of each detector to maintain the pressure within the chromatography system at a predetermined level.

[0009] However, this is associated with problems regarding sample introduction. These are described in detail, for example, in publications US 6,428,70 2B1 and US 6,576,125 B2.

[0010] The well-established HPLC and SFC methods have long been used for both analytical and preparative purposes, and the necessary equipment is commercially available. However, there is a general desire to improve the performance of these systems and methods.

[0011] There is a particular interest in increasing the purity of the separated or purified substances. Furthermore, the loss of substances to be separated or purified due to the purification process should be minimized. Additionally, the chromatography system or chromatography method should be capable of processing successive, potentially unrelated samples as quickly as possible and without contamination from previous samples.

[0012] In light of the prior art, the object of the present invention is therefore to provide a chromatography system that solves the problems outlined above. In particular, the system should produce exceptionally pure products with high yields. Furthermore, the system should have a high throughput, enabling the rapid application and purification of various samples without the need for time-consuming purification cycles. Additionally, the substances to be separated should be able to exhibit minimal differences in transit time without compromising their separation within the system. Moreover, for a given transit time difference, the system should achieve the highest possible separation of batches. Most importantly, the chromatography system should provide excellent separation, resulting in highly accurate detection signals for the substances to be separated.

[0013] Another task is to provide a chromatography system that can be operated and manufactured in a particularly cost-effective and low-maintenance manner.

[0014] The system should be as simple and inexpensive to operate as possible and should lead to further cost and handling advantages.

[0015] Furthermore, the chromatography system should be as inexpensive as possible in relation to the volume flow rate with which it is operated.

[0016] Furthermore, the aim of this invention is to provide a method for carrying out chromatography that achieves the highest possible yield of purified substances. The separated substances should exhibit the highest possible purity. Furthermore, the method should be as simple and cost-effective as possible, leading to further cost and handling advantages.

[0017] Furthermore, a high yield and purity of the substances to be separated should be achievable for as many different liquid mixtures or gas-liquid mixtures as possible.

[0018] Furthermore, an object of the present invention is to provide components that enable the simplest possible conversion of a known HPLC system to an SFC system. This should also allow for the conversion of preparative HPLC systems.

[0019] These and other tasks not explicitly mentioned, which can nevertheless be readily derived or deduced from the contexts discussed in the introduction herein, are solved by a chromatography system with all the features of claim 1.

[0020] The present invention relates accordingly to a chromatography system comprising a first pump, which is connectable to or connected with a liquid reservoir for a first fluid, and a second pump, which is connectable to or connected with a liquid reservoir for a second fluid, wherein the pump outlet lines of the first pump and the second pump are connected by a connecting piece, and a chromatography column is provided downstream of this connecting piece in the direction of flow, and an injection unit is provided upstream of the chromatography column in the direction of flow, characterized in that the injection unit comprises a sample loop and an injection valve, wherein the injection valve has at least two sample loop ports and two high-pressure ports for supplying and discharging fluid under high pressure, as well as two sample loading ports for loading the sample loop.wherein the sample loop is connectable to or connected with the two sample loop ports of the injection valve, and a third pump is provided, the outlet line of which is connected to a high-pressure port of the injection valve and the inlet line of the third pump is switchable via a pump supply line switching valve, wherein in a first switching position of the pump supply line switching valve the inlet line of the third pump is connectable to or connected with a liquid reservoir for a third fluid and in a second switching position of the pump supply line switching valve the inlet line of the third pump is connectable to or connected with a sample loading port of the addition unit.

[0021] The present invention particularly enables the production of exceptionally pure products with high yields. Furthermore, the system offers high throughput, allowing for the rapid application and purification of various samples without the need for time-consuming cycles for purification and / or equilibration of the chromatographic acid. In particular, the reproducibility of cycles for purification and / or separation of sample compositions is significantly increased, enabling peak prediction with improved accuracy.

[0022] In particular, compared to other chromatography systems, this system offers an improvement in that it can achieve very high batch separation even with a given runtime difference. Furthermore, very good separation can be achieved with a relatively small runtime difference between the substances to be separated. In particular, very narrow signals are obtained for the substances being separated during detection.

[0023] Even very simply designed pumps can be used, resulting in further investment cost advantages. This applies particularly to the first and second of the pumps described above.

[0024] Furthermore, very good results are also achieved with chromatography methods where the system is operated with a gradient. In addition, an SFC process can be carried out even with very different aerosol flow rates without significantly impairing the economic advantages.

[0025] Furthermore, the present method and the chromatography system used to carry out the procedure can reduce the complexity and cost of the technical equipment required for setting up SFC analysis. This also allows for the conversion of HPLC systems intended for preparative use.

[0026] The chromatography system according to the invention comprises at least two pumps, a first pump and a second pump. The type of pump is irrelevant for the present invention. Rotary lobe pumps, centrifugal pumps, gear pumps, and piston pumps can be used. However, the invention allows the use of cost-effective piston pumps, which preferably comprise at least two pistons. In piston pumps with at least two pistons, the two pistons can be controlled via a camshaft. Furthermore, the two pistons can be controlled independently of each other, with control via a camshaft being often more cost-effective and suitable for the purposes of the present invention. Preferably, the first pump and / or the second pump is designed as a piston pump, with the pump head preferably being coolable. Cooling the pump head is particularly advantageous in a chromatography system designed as an SFC system.

[0027] The present invention makes it particularly surprising that excellent separation performance can be achieved even with cost-effective pumps.

[0028] The first pump is connectable to, or already connected to, a fluid reservoir for a first fluid, and a second pump is connectable to, or already connected to, a fluid reservoir for a second fluid. The type of fluid reservoir is not specifically limited and can be designed according to the specific requirements.

[0029] Preferably, the liquid reservoir for a second fluid and the second pump are provided with a cooling system for the fluid. This embodiment is particularly advantageous in a chromatography system designed as an SFC system. This embodiment ensures that no or only minimal gas formation occurs, which is especially important at relatively low reservoir pressures, for example, at CO2 pressures of 70 bar or less, and particularly at 60 bar or less.

[0030] In a preferred embodiment, the second pump can be configured as a system for pumping a compressible liquid. A preferred system for pumping a compressible liquid is known from the prior art, for example from document WO 2019 / 086671 A1, application number PCT / EP2018 / 080182, filed on November 5, 2018, the disclosure of which is incorporated in its entirety into the present application by reference thereto for disclosure purposes.

[0031] The pump outlet lines of the first and second pumps are joined in a connector and routed from this connector into a common outlet line. A chromatography column is installed downstream of this connector, in the direction of flow. Such connectors are well-known and are not subject to any particular limitations.

[0032] Viewed in the direction of flow, an injection unit is provided upstream of the chromatography column. Preferably, the injection unit is located downstream of the connecting piece. A sample to be separated is fed into the chromatography system via the injection unit and applied to the chromatography column. The injection unit comprises a sample loop and an injection valve, the injection valve having at least two sample loop ports, two high-pressure ports for supplying and discharging high-pressure fluid, and two sample loading ports for loading the sample loop.

[0033] Preferably, the injection valve may comprise eight ports, with two ports serving as sample loop ports, two ports serving as high-pressure ports for supplying and discharging high-pressure fluid, two sample loading ports for loading the sample loop, and two sealed ports. This configuration offers significant advantages, particularly when samples are purified by chromatography over extended periods.

[0034] Particularly preferably in an embodiment in which an injection valve with eight ports is used, it can be provided that in a first switching position of the injection valve the two high-pressure ports for supplying and discharging fluid under high pressure are connected to each other, and the two sample loading ports for loading the sample loop are connected to the two sample loop ports, and the two closed ports are connected to each other.

[0035] Furthermore, in an embodiment where an injection valve with eight ports is used, it is particularly preferred that, in a second switching position of the injection valve, two high-pressure ports for supplying and discharging high-pressure fluid are connected to the two sample loop ports, and the two sample loading ports for loading the sample loop are connected to the two closed ports. The addition unit comprises a sample loop into which a sample to be separated can be introduced, for which purpose the injection valve is moved to a suitable switching position. The sample loop can be connected to, or is preferably connected to, the injection valve via the two sample loop ports. The sample loop can preferably be loaded with a sample by means of a vacuum, this vacuum being generated by the third pump, as described below.The sample loop is preferably unloaded by pressure generated by the third pump. The volume of the sample loop can be selected according to requirements. Preferably, the volume of the sample loop can be in the range of 0.5 ml to 30 ml, more preferably in the range of 1 ml to 20 ml, and most preferably in the range of 2.5 ml to 10 ml.

[0036] The chromatography system includes a third pump, wherein the outlet line of the third pump is connected to a high-pressure port of the injection valve and the inlet line of the third pump can be switched via a pump supply line switching valve.

[0037] In a first switching position of the pump supply line switching valve, the inlet line of the third pump can be connected to a liquid reservoir for a third fluid, and in a second switching position of the pump supply line switching valve, the inlet line of the third pump can be connected to a sample loading port of the addition unit.

[0038] The inlet line of the third pump is connectable to, or connected to, a sample loading port of the addition unit, which comprises a sample loop and an injection valve. This implies that the inlet line of the third pump is connectable to, or connected to, a sample loading port of the injection valve of the addition unit. This is particularly evident in the figures.

[0039] The type of third pump is irrelevant for the present invention, and the pump types described above can be used. Surprising advantages can be achieved by using a stepper motor pump as the third pump. This design allows a sample to be applied to the chromatography column at very low flow rates without any problems regarding precision or efficiency.

[0040] The chromatography system of the present invention comprises a pump supply line switching valve and an injection valve, as described above and below. Preferably, the pump supply line switching valve and the injection valve can be switched in a coordinated manner. This results in simplified and reliable control of the injection process. This control can be achieved by a controller that may, among other things, be part of a chromatography system control unit.

[0041] For loading the sample loop or for adding a third solvent, which in one embodiment is identical to the first solvent, to the chromatography column, the pump supply switching valve and the injection valve can be switched separately.

[0042] In a preferred embodiment, it can be provided that in a first switching position of the pump supply line switching valve, the inlet line of the third pump is connected to a liquid reservoir for a third fluid, and the injection valve of the addition unit is switched in a first switching position, wherein the two high-pressure ports for supplying and discharging high-pressure fluid are connected to each other, and the sample loading ports for loading the sample loop are connected to the two sample loop ports. In this first switching position of the injection valve of the addition unit and the first switching position of the pump supply line switching valve, the sample loop is neither loaded nor unloaded with a fluid via the third pump.

[0043] Furthermore, it can preferably be provided that in a second switching position of the pump supply line switching valve, the inlet line of the third pump is connected to a sample loading port of the addition unit, and the injection valve of the addition unit is switched in a first switching position, wherein the sample loading ports for loading the sample loop are connected to the two sample loop ports. In this first switching position of the injection valve of the addition unit and the second switching position of the pump supply line switching valve, the sample loop is loaded with a sample via the third pump.Furthermore, it is preferably provided that in a first switching position of the pump supply line switching valve, the inlet line of the third pump is connected to a liquid reservoir for a third fluid, and the injection valve of the addition unit is switched in a second switching position, wherein the two high-pressure ports for supplying and discharging high-pressure fluid are connected to the two sample loop ports. In this second switching position of the injection valve of the addition unit and the first switching position of the pump supply line switching valve, the sample loop is discharged via the third pump by supplying a third fluid, so that a sample is deposited onto the chromatography column.

[0044] Preferably, the pump supply line switching valve may have at least four ports, wherein one port is connected to the inlet line of the third pump, one port is connected to a sample loading port for loading the sample loop of the injection valve, one port is connected to a liquid reservoir for a third fluid, and one port serves for pressure relief.

[0045] It is particularly preferred that the pump supply line switching valve has at least 6 ports, wherein one port is connected to the inlet line of the third pump, two ports are connected to two sample loading ports for loading the sample loop of the injection valve, one port is connected to a liquid reservoir for a third fluid, one port is connected to a sample container and / or a sample feeder, and one port serves for pressure relief. A pump supply line switching valve with at least 6 ports, preferably at least 7 ports, allows the use of a system for flushing a sample feeder. A system for flushing a sample feeder typically comprises a liquid reservoir for a fluid and a pump for flushing, which may, for example, be designed as a peristaltic pump, although other pumps may also be used, as described herein.The liquid reservoir for a fluid may preferably comprise a first or a third solvent, as set forth herein.

[0046] During injection, pressure builds up in the sample loop due to the pumped third fluid. If the sample loop is further loaded, this pressure could cause at least some of the third fluid, which is already in the loop, to be transferred into a sample container. This can lead to an undesirable dilution of the sample in the sample container.

[0047] In a further embodiment, the pump supply switching valve can have fewer ports, for example three ports, in which case a sample loading port for loading the sample loop of the injection valve can be directly connected to a sample container.

[0048] If the pump supply line switching valve has at least 6 ports, it can be provided that in a first switching position of the pump supply line switching valve, the inlet line of the third pump is connected to a liquid reservoir for a third fluid, and a port connected to a sample loading port for loading the sample loop of the injection valve is connected to the port used for pressure relief. In a further embodiment, it can be provided that in a second switching position of the pump supply line switching valve, the inlet line of the third pump is connected to a sample loading port of the addition unit, and the port connected to a sample container is connected to a port connected to a sample loading port for loading the sample loop of the injection valve.

[0049] In a preferred embodiment, a second connecting piece may be provided, which, viewed in the direction of flow, is located downstream of the first connecting piece and upstream of the chromatography column. This second connecting piece is connected to the first connecting piece and the chromatography column via a high-pressure port for supplying and discharging high-pressure fluid from the injection valve. Preferably, a check valve is provided between the high-pressure port for supplying and discharging high-pressure fluid from the injection valve and the second connecting piece.

[0050] By designing a chromatography system with a previously described addition unit in combination with a third pump, whose inlet line can be switched via a pump inlet control valve, surprising advantages in the performance of the chromatography system can be achieved, as previously explained. These advantages are potentially achieved by allowing the sample to be applied over a small volume. For example, relatively highly concentrated samples can be introduced into a flow stream, which then dilutes them to such an extent that no precipitate forms. This can be accomplished, for instance, by using a third solvent in which the sample dissolves very well, or by adjusting the flow rate at which the sample is fed into the system. Furthermore, the volume flowed through the system during application can be kept to a minimum.In particular, the sample does not need to pass through the volume of a mixer during application. Furthermore, the line between the addition unit or a second connecting piece and the chromatography column can be kept short, thus minimizing unwanted diffusion of the sample during application.

[0051] Preferably, the addition unit is controllable via a control system. In a particularly preferred embodiment of the present invention, the chromatography system can comprise several sample containers, wherein the control system of the chromatography system or the addition unit enables samples to be taken from the various sample containers and applied sequentially to the chromatography column. This allows a preferred chromatography system to purify various samples over a longer period and collect the fractions of different samples in different containers of the fraction collection device or fraction collector. For example, a sampling needle can take samples from different sample containers. It may be advantageous to flush the sampling needle and the lines between the sampling needle and the valve to which the sampling needle is connected.A system for providing different samples, comprising several sample containers so that different samples can be automatically fed to the chromatography system, is also referred to herein as a sample feeder. Preferably, a sample feeder can be connected to a rinsing system to clean the previously described sample needle between different applications.

[0052] Furthermore, the chromatography system can include a system for rinsing the sample loop, typically comprising a fluid reservoir and a rinsing pump, which may, for example, be a peristaltic pump, although other pumps may also be used, as described herein. The fluid reservoir may preferably include a first or a third solvent, as described herein. This system can be connected to a port of the pump supply control valve, as further details are shown in the figures. This sample loop rinsing system can be combined with a sample feeder rinsing system, although this is not necessary.

[0053] Furthermore, the sample loop can be flushed using a combination of the switching positions of the pump supply valve and the injection valve, which is intended for loading the sample loop. Preferably, the flushing fluid is not passed through a chromatography column to minimize contamination. Accordingly, the chromatography system preferably includes a flushing control valve located in the connecting line between the injection valve and the chromatography column, with the flushing control valve connected to a waste container. The flushing control valve can also be part of a chromatography column selection unit, as described, among other things, in the publication.

[0054] WO 2013 / 134222A1 as a column manager (SFC column manager) is explained, among other things, on page 5, lines 10 to 15, where a column unit can be designed as an empty column.

[0055] The chromatography system preferably includes at least one mixer. In a preferred embodiment, a mixer is provided between the connecting piece and the feed unit. If the system includes a second connecting piece, this is located downstream of the mixer and upstream of the chromatography column when viewed in the direction of flow.

[0056] If a mixer is used, it can be designed as either an active or passive mixer. Surprising advantages can be achieved through the use of passive mixers. Particularly significant, unpredictable advantages can be obtained by designing the mixer as a static mixer. Static mixers comprise flow-modifying elements that are incorporated into a body with an inlet and an outlet. For example, a tubular body containing inert particles can be used as a static mixer.

[0057] The mixer volume can be selected according to the user's needs, generally depending on the system's performance, such as the flow rate it can provide. The higher the flow rate, the larger the preferred mixer volume. Furthermore, the mixer may have a volume in the range of 0.5 ml to 60 ml, preferably in the range of 1 ml to 30 ml.

[0058] Furthermore, it may be provided that the system can be used to perform solvent gradient chromatography.

[0059] Preferably, the chromatography system can be controlled via a chromatography system control system.

[0060] Furthermore, the chromatography system may include at least one detector. Preferably, the chromatography system may include a UV detector. It may also include a mass spectrometer as a detector. In a particularly preferred embodiment, the system includes both a UV detector and a mass spectrometer.

[0061] Furthermore, the chromatography system may include a fraction collector or other device through which the purified samples can be collected.

[0062] A special embodiment of a fraction collection device, as described below, offers surprising advantages, particularly regarding cost-effectiveness, ease of operation, and verifiability of results. Such a fraction collection device is novel and inventive and is therefore also the subject of the present invention.

[0063] A further object of the present invention is a chromatography system comprising a first pump, which is connectable to or connected with a liquid reservoir for a first fluid, and a second pump, which is connectable to or connected with a liquid reservoir for a second fluid, wherein the pump outlet lines of the first pump and the second pump are connected by a connecting piece, and a chromatography column is provided downstream of this connecting piece in the direction of flow, and an injection unit is provided upstream of the chromatography column in the direction of flow, wherein the chromatography system comprises a fraction collection device provided downstream of the chromatography column in the direction of flow, characterized in that the fraction collection device comprises a first fraction switching valve and a second fraction switching valve, wherein the first fraction switching valve has at least four ports.wherein one port of the first fraction switching valve is connected to the outlet line of the chromatography column, one port of the first fraction switching valve is connected to the outlet line of a rinsing pump, one port of the first fraction switching valve is connected to a port of the second fraction switching valve, one port of the first fraction switching valve is connected to a fraction collector or a waste collection vessel.

[0064] A fraction collection device comprises a first fraction switching valve and a second fraction switching valve, and preferably includes further components that can serve to collect fractions. For example, a fraction collection device can include a few, for example 19 or fewer, preferably 16 or fewer, larger collection vessels, which, depending on the operating mode, serve to collect waste fractions or valuable fractions of a sample. Furthermore, a fraction collection device can include a fraction collector comprising a plurality of smaller collection vessels, for example at least 20, preferably at least 30 or more. It should also be mentioned that fraction collectors comprising a plurality of smaller collection vessels are often connected to a waste collection vessel, with valuable fractions being directed into the smaller collection vessels via a valve and uninteresting fractions into a waste collection vessel.Therefore, the expression "connected to a fraction collector or waste collection container" is to be understood inclusively.

[0065] It should be noted that the features of the second article according to the invention can be combined arbitrarily with the features of the first article, wherein the addition unit of the second article is not limited to the previously described addition unit comprising an injection valve, a third pump and a pump supply line switching valve, but addition units known from the prior art can also be used here as well, for example, suitable addition units are described in documents DE 10 2008 006266 A1, WO 2008 / 107562 A2, WO 2010 / 139359 A1, DE 2020 / 16100451 U1, WO 2018 / 128836 A1, WO 2013 / 134222 A1 and EP 4215912 A1, wherein, for disclosure purposes, the description of the addition units described in these documents is incorporated into the present application by reference thereto. Preferably, however, a Addition unit comprising an injection valve, a third pump and a pump supply line switching valve,used as previously described, whereby the previously described preferred configurations can also be used here, resulting in surprising synergies, which are particularly evident in high yield, high purity and excellent separation efficiency.

[0066] Furthermore, it may be provided that in a first switching position of the first fraction switching valve, the outlet line of the chromatography column is connected to the fraction collector or the waste collection vessel and the outlet line of a rinsing pump is connected to a port of the second fraction switching valve.

[0067] Furthermore, it may be provided that in a second switching position of the first fraction switching valve, the outlet line of the chromatography column is connected to a port of the second fraction switching valve.

[0068] Furthermore, the first fraction switching valve may have at least five ports, the fifth port being connected to a port of a pump supply line switching valve, as previously described, particularly in connection with the first subject matter of the present invention. It may be provided that, in a second switching position of the first fraction switching valve, the outlet line of the chromatography column is connected to a port of the second fraction switching valve, and the outlet line of a rinsing pump is connected to a port of the pump supply line switching valve. In a particularly preferred embodiment of the present invention, the chromatography system may be configured as an SFC system. Here, the chromatography system preferably comprises a chromatography column and, viewed in the direction of flow, at least one backpressure regulator.

[0069] It is particularly preferred that a gas-liquid separator be provided downstream of the back pressure regulator when viewed in the direction of flow.

[0070] An example of such an SFC chromatography system is operated using supercritical CO2 together with a solvent, for example, methanol. Accordingly, a chromatography system designed for supercritical liquid chromatography has at least one storage tank for the solvent and one storage tank for the supercritical fluid, for example, CO2. Generally, the fluid is drawn from the storage tank and transferred by at least one pump into a mixer, which is in fluid contact with a chromatography column. The pumps and / or the mixer, as well as the chromatography column, can be equipped with temperature control to allow for the setting of a predefined temperature. Heat exchangers can be used for this purpose.The addition of mixtures to be separated, in particular substances to be purified, can be carried out by a previously described addition unit, which is preferably provided in the line in which the solvent is fed to the mixer.

[0071] The fluid exiting the chromatography column is preferably at least partially fed to a detection or analysis unit. Examples of detection or analysis units include UV detectors and / or mass spectrometers.

[0072] Preferably, the chromatography system includes an injection unit, preferably an injection device, with which samples can be automatically injected into the chromatography system. A preferred embodiment is described above for the first subject matter of the present invention.

[0073] The fluid exiting the chromatography column is preferably at least partially fed to a detection or analysis unit. Preferably, the chromatography system may include a UV detector. Furthermore, the chromatography system may include a mass spectrometer as a detector. In a particularly preferred embodiment, the system comprises both a UV detector and a mass spectrometer. Other detection methods can also be employed, such as measuring light scattering, fluorescence, or the refractive index. Mass spectrometers and / or conductivity detectors, etc., are also frequently used. Detectors can also be used for HPLC systems, so these embodiments are applicable to both SFC and HPLC systems.

[0074] A backpressure regulator is generally provided downstream of the chromatography column and preferably downstream of the detection or analysis unit, and preferably a heat exchanger is provided downstream of the backpressure regulator. The aerosol leaving the heat exchanger is preferably subsequently fed to a gas-liquid separator.

[0075] Preferred gas-liquid separators are known from the prior art, for example from publication WO 2014 / 012962 A1 with application number PCT / EP2013 / 06067 with filing date 17 July 2013, the disclosure of which is incorporated in its entirety into the present application by reference thereto for disclosure purposes.

[0076] A particularly preferred gas-liquid separator is set forth in PCT application WO 2018 / 210818 A1, application number PCT / EP2018 / 062537, filed on May 15, 2018. The disclosure of that document, in particular the gas-liquid separators set forth therein and the preferred embodiments thereof, is incorporated in its entirety into the present application for disclosure purposes by reference thereto. In particular, the embodiments of the gas-liquid separators set forth in Figures 1 to 9 are incorporated into the present application for disclosure purposes by reference to PCT application number PCT / EP2018 / 062537.

[0077] An unexpected improvement in impact separation can be achieved through the arrangement and design of a separation orifice. This allows, in particular, a reduction in the gas volume supplied during impact separation, thus decreasing the overall volume of the gas-liquid separator. This can surprisingly improve the separation efficiency of the chromatography system.

[0078] A preferred gas-liquid separator comprises a separation area with an inlet nozzle, an impact unit, and a gas guide unit.

[0079] Preferably, the separation area is designed to effect impact separation. Impact separation means that the liquid droplets contained in the aerosol are directed against an impact unit, allowing the liquid droplets to form a liquid film.

[0080] Any body against which the aerosol stream can be directed can serve as an impactor. For example, the aerosol stream can be directed against an upper area of ​​the separation zone, such as the upper edge of the separation zone. A projection, such as a dome or similar structure, can be provided against which the aerosol stream is directed, so that the liquid droplets directed onto the impactor are not thrown back or rebound from the impactor, but instead form a film.

[0081] A preferred gas-liquid separator utilizes gravity during operation to separate the gas and liquid. Accordingly, the term "above" refers to the orientation of the gas-liquid separator during operation, such that gas can flow upwards, while "below" is the opposite direction, through which liquid exits the gas-liquid separator.

[0082] In addition to an impact unit, an inlet nozzle is preferably provided in the separation area of ​​the gas-liquid separator. The aerosol is directed through the inlet nozzle into the gas-liquid separator, in particular into the separation area of ​​the gas-liquid separator.

[0083] The inlet nozzle is preferably designed such that a gas / liquid stream passed through the inlet nozzle can be directed against the impact unit, as previously described with regard to the impact unit. The shape and type of the inlet nozzle are not critical and can therefore be selected by a person skilled in the art within the scope of their expertise. For example, the inlet nozzle can be designed so that the aerosol is directed onto the impact unit in the form of a very narrow jet. Alternatively, the inlet nozzle can also be designed so that a conical spray is directed onto the impact unit.

[0084] The gas-liquid separator preferably has a separation opening arranged between the separation zone and the separation zone, creating a gas- and liquid-open connection between these zones. Inertial separation is preferably effected through the separation opening. This means that the liquid, which flows downwards as a film at the impact unit and / or the gas guide unit, is separated from the gas by inertia. The gas preferably accelerates the liquid, so that the liquid is transferred into the separation zone at a higher velocity than it would be without this gas acceleration.In this process, the liquid film preferably remains on a wall of the separation zone, which is preferably designed as part of the impact unit and / or the gas guide unit, in the form of a film and transitions directly into the separation zone without leaving this wall. In contrast to the liquid phase, the gas phase does not adhere to a wall but is able to escape upwards and pass into the gas discharge zone. Conversely, the liquid is discharged into the separation zone and removed from the gas-liquid separator via the liquid outlet provided in the separation zone.

[0085] Preferably, the distance between the inlet nozzle and the impact unit is greater than the smallest longitudinal dimension of the separation orifice. This distance is determined by the path of the aerosol from the inlet nozzle to the impact unit. The smallest longitudinal dimension of the separation orifice refers to its width or length, where the extent of the plane extending to the edge of the separation orifice is defined as the plane between the separation zone and the separation zone, resulting in a minimum area of ​​the separation orifice. Within this plane, the length of the longest dimension of the separation orifice is determined, allowing the shortest length of the separation orifice, perpendicular to this longest dimension, to be measured. This smallest longitudinal dimension can also be considered the width of the separation orifice.

[0086] The spatial shape of the separation area is not critical and can be adapted to specific requirements. A gas guidance unit is preferably formed within the separation area. This gas guidance unit alters the gas flow velocity, resulting in a lower gas velocity at the inlet nozzle than at the separation opening. Since the volumetric flow rate can be considered constant for a given aerosol composition, this means that the aerosol is initially directed into a relatively large space, which is then constricted, thus increasing the flow velocity.

[0087] Accordingly, the cross-sectional area of ​​the separation zone can, for example, be circular, preferably narrowing in a wedge shape from the inlet nozzle towards the separation opening. In a preferred embodiment, the separation zone does not have a circular cross-sectional area in the region of the inlet nozzle, and preferably comprises at least three side walls which, together with an upper closure, define a space that is connected to the separation zone via the separation opening.

[0088] The gas discharge area serves to discharge the gas phase from the gas-liquid separator, so that it includes a gas outlet.

[0089] Preferably, the gas discharge area is designed such that the gas velocity at the gas outlet is maximized, and preferably, the gas velocity increases in the direction of gas flow from the separation area towards the gas outlet. This creates a suction effect, resulting in reliable and low-maintenance operation of the gas-liquid separator. Furthermore, this design allows for a reduction in the volume of the gas-liquid separator without compromising its performance in other areas, such as its separation properties. Conversely, the volume of the separation area decreases from the separation area towards the gas outlet. Accordingly, the cross-sectional area preferably tapers from the separation area towards the gas outlet.

[0090] Depending on the type of gas, the gas phase of the aerosol can be captured and processed or, for example when using CO2, released into the environment.

[0091] The liquid phase of the aerosol is preferably collected in a fraction collector. The collected fractions are particularly preferably automatically collected as main fractions, while excess solvent can be subjected to treatment or disposal. Conventional fraction collectors, characterized by a plurality of smaller collection vessels, for example 20, 30 or more, or other fraction collection devices comprising a few, for example 19 or fewer, preferably 16 or fewer, larger collection vessels, can be used. A preferred embodiment can include both of these configurations, as described herein as the second subject matter of the invention. The connecting line between the liquid outlet of the gas-liquid separator and the fraction collector can preferably be designed such that residual gas phase, preferably residual CO2, can escape via this connection.A semipermeable plastic material can be used for this purpose, for example Teflon, especially preferably AF 2400 (commercially available from DuPont).

[0092] A preferred method for operating a fractionation collector in chromatography is known from the prior art, for example in publication WO 2019 / 048369 A1 with application number PCT / EP2018 / 073503 with filing date 03 September 2018, the disclosure of which is incorporated in its entirety into the present application by reference thereto for disclosure purposes.

[0093] Furthermore, the chromatography system may include a chromatography system control unit that interacts with a detector and a fraction collector or fraction collection device. Preferably, the control unit is programmable such that the amount of liquid that can be introduced into a vessel of the fraction collector can be determined depending on the proportion of the first solvent.

[0094] Furthermore, the chromatography system may include a chromatography system control unit that is operatively connected to the first pump, whereby the pumping capacity of the first pump can be controlled via the chromatography system control unit. Additionally, the chromatography system control unit may also be operatively connected to the second pump and control its pumping capacity.

[0095] Preferably, the chromatography system is designed as an SFC system, whereby chromatography with a solvent gradient can be carried out.

[0096] The SFC chromatography system is preferably operable at a flow rate in the range of 10 ml / min to 450 ml / min, particularly preferably in the range of 50 ml / min to 300 ml / min, and especially preferably in the range of 100 ml / min to 250 ml / min. Furthermore, it can be provided that the SFC chromatography system is preferably operable at a flow rate of at least 10 ml / min, particularly preferably at least 50 ml / min, and especially preferably at least 100 ml / min.

[0097] Furthermore, the chromatography system can be configured as an HPLC system. An HPLC system differs from an SFC system, among other things, in that an HPLC system does not have a backpressure regulator, which, particularly when viewed in the direction of flow, is located downstream of a chromatography column. Additionally, HPLC systems do not include a gas-liquid separator downstream of the backpressure regulator when viewed in the direction of flow.

[0098] According to another aspect, a conversion kit is also provided, which allows a high-performance liquid chromatography (HPLC) system to be converted into a solid fuel cell (SFC) system. Such a kit comprises at least one gas-liquid separator and at least one pump inlet switching valve, as described above. Preferably, the kit includes further components, as described above and below, to convert an HPLC system into an SFC system, such as heat exchangers or backpressure regulators. Preferably, the kit may include a stepper motor pump.

[0099] Depending on the specific design of the system to be modified, different components are required. Ideally, one of the pumps in the HPLC system is suitable for operation with a compressible liquid, particularly liquid or supercritical CO2.

[0100] Another object of the present invention is a method for carrying out chromatography comprising the use of a chromatography system according to the invention.

[0101] Preferably, it can be provided that when loading the sample loop, the pump supply switching valve is switched to the second switching position and the injection valve of the addition unit is switched to a second switching position, wherein the sample loading ports for loading the sample loop are connected to the two sample loop ports, so that the third pump draws the sample to be separated from a sample storage container into the sample loop.

[0102] Furthermore, it can be provided that when a sample to be separated is applied to the chromatography column, the pump supply switching valve is switched to the first switching position and the injection valve of the addition unit is switched to a second switching position, with the sample loading ports for loading the sample loop being connected to the two high-pressure ports for supplying and discharging fluid under high pressure, so that the third pump pumps the sample to be separated from the sample loop to the chromatography column with a third solvent.

[0103] In a preferred embodiment, gradient chromatography can be performed, wherein the proportion of the first fluid at the beginning of the chromatography is in the range of 0 to 10 vol.% and this proportion of the first fluid is increased, wherein the pump supply switching valve is switched to the first switching position and the injection valve of the addition unit is switched to a first switching position, wherein the two high-pressure ports for supplying and discharging high-pressure fluid are connected to each other, so that the third pump provides at least 50 vol.% of the first fluid at the beginning of the chromatography to form the desired fluid mixture comprising a first and a second fluid.

[0104] Furthermore, it may be provided that the fraction collector or fraction collection device is controlled via a control unit and that the control unit is in operative communication with a detector, whereby when a substance is detected by the detector, a control pulse is sent to the fraction collector or fraction collection device, which causes a change of the collection vessel.

[0105] In a further embodiment, the fraction collector or fraction collection device can be controlled by a control unit, and the control unit is operatively connected to the detector. After the detector has completed the detection of a substance, a control pulse is sent to the fraction collector or fraction collection device, causing a change of the collection vessel. This configuration is preferred over the embodiment in which a change of the collection vessel occurs at the beginning.

[0106] In a process using a fraction collection device with a first fraction switching valve and a second fraction switching valve, it can be provided that, when separating uninteresting parts of a sample, the first fraction switching valve is switched to the first switching position and the outlet line of a rinsing pump is connected to a port of the second fraction switching valve, wherein the outlet line of the chromatography column is connected to a waste collection vessel.

[0107] Furthermore, in a process using a fraction collection device with a first fraction switching valve and a second fraction switching valve, it can be provided that, when collecting valuable fractions of a sample, the first fraction switching valve is switched to the second switching position and the outlet line of the chromatography column is connected to a port of the second fraction switching valve. In this operating mode, valuable fractions can be collected in a large collection container.Furthermore, in a process using a fraction collection device with a first fraction switching valve and a second fraction switching valve, it can be provided that, when collecting valuable fractions of a sample, the first fraction switching valve is switched to the first switching position and the outlet line of a rinsing pump is connected to a port of the second fraction switching valve, wherein the outlet line of the chromatography column is connected to a fraction collector.

[0108] Furthermore, in a process using a fraction collection device with a first fraction switching valve and a second fraction switching valve, it can be provided that, when separating uninteresting fractions of a sample, the first fraction switching valve is switched to the second switching position and the outlet line of the chromatography column is connected to a port of the second fraction switching valve. In this operating mode, fractions whose value is uncertain can be collected in a large collection container before final disposal.

[0109] In one embodiment, an SFC process is carried out. For this purpose, it can be provided that the liquid reservoir for a first fluid contains a first solvent that is liquid under normal conditions, and the liquid reservoir for a second fluid contains a gaseous solvent under normal conditions. Furthermore, it can be provided that the liquid reservoir for a third fluid contains a third solvent that is liquid under normal conditions. In one embodiment, the third solvent can be identical to the first solvent. Alternatively, the third solvent can differ from the first solvent.

[0110] With regard to the term “SFC method” or “supercritical fluid chromatography (SFC)”, it should be noted that a supercritical state does not necessarily have to be reached or maintained throughout the entire course of a chromatography.

[0111] Rather, the term “SFC method” or “supercritical fluid chromatography (SFC)” means that chromatography is carried out using a compressible substance that is easily brought into a supercritical state and is preferably gaseous under normal conditions.

[0112] In an SFC method, a solvent composition is preferably pumped into a chromatography column. This composition contains at least a proportion of a first solvent, which is liquid under standard conditions, and a proportion of a second solvent, which is gaseous under standard conditions. This is therefore preferably an SFC as described above and below. Standard conditions are defined as 273.15 K = 0 °C and 1.01325 bar according to DIN 1343.

[0113] For separation using a supercritical fluid, an inorganic or organic solvent is employed which is liquid under the usual separation conditions, preferably at 25°C and atmospheric pressure (1013.25 mbar). A polar or nonpolar solvent can be used, depending on the type of compounds to be separated or purified. These substances are referred to herein as the first solvent.

[0114] Preferably, the first solvent is selected from an alcohol, preferably methanol, ethanol, or propanol; hexane; mixtures with dichloromethane, chloroform; water (preferably up to a maximum of 3% by volume, as otherwise a miscibility gap may occur); an aldehyde or a ketone, preferably methyl ethyl ketone; an ester, preferably ethyl acetate; or an ether, preferably tetrahydrofuran; an aliphatic hydrocarbon, preferably hexane, cyclohexane, heptane, or dexamethasone; or an aromatic hydrocarbon, preferably benzene, toluene, or xylene. These compounds can be used individually or as a mixture.

[0115] Furthermore, it can be provided that in a process according to the invention, a gas is preferably used which can be brought to a supercritical state relatively easily. Preferred gases exhibiting these properties include, among others, carbon dioxide (CO2), ammonia (NH3), Freon, and xenon, with carbon dioxide (CO2) being particularly preferred. These substances are referred to herein as the second solvent. It can be preferably provided that the gas-liquid mixture to be brought to the supercritical state comprises a polar solvent and a gas selected from the group consisting of CO2, NH3, Freon, and xenon, preferably CO2. Preferably, the polar solvent is an alcohol, preferably methanol, ethanol, or propanol, hexane, mixtures with dichloromethane, chloroform, or water (preferably up to a maximum concentration of 1000 mg / L).3 vol%, as otherwise a miscibility gap may occur), an aldehyde or a ketone, preferably methyl ethyl ketone; an ester, preferably ethyl acetate; or an ether, preferably tetrahydrofuran.

[0116] Furthermore, the gas-liquid mixture to be brought to the supercritical state may comprise a nonpolar solvent and a gas selected from the group consisting of CO2, NH3, Freon, Xenon, preferably CO2. Preferably, the nonpolar solvent is an aliphatic hydrocarbon, preferably hexane, cyclohexane, heptane, or dexpane; an aromatic hydrocarbon, preferably benzene, toluene, or xylene; an ester, preferably ethyl acetate; or an ether, preferably tetrahydrofuran.

[0117] The composition flowing from the chromatography column is preferably introduced, at least partially, into a detector. Accordingly, the composition is preferably analyzed downstream of the chromatography column. Detectors suitable for this purpose are generally known, particularly spectroscopic methods using electromagnetic waves, such as UV or Vis spectroscopy. Other detection methods can also be employed, such as measuring light scattering, fluorescence, or the refractive index. Furthermore, mass spectrometers and / or conductivity detectors, etc., are frequently used.

[0118] These methods can continuously or batchwise measure the properties of the composition flowing from the chromatography column, allowing these detectors to determine these properties in flow or by sampling, the latter generally being fully automated and continuous. Details of these techniques are known from the prior art, with particular reference to detectors such as those used in conventional HPLC methods.

[0119] Preferably, a composition containing the first solvent is introduced, after exiting the chromatography column, into a collection vessel of the fraction collector or fraction collection device, as described above and below, depending on the detector signal. It is particularly preferred that the amount of liquid introduced into a collection vessel of the fraction collector is selected depending on the proportion of the first solvent.

[0120] This measure makes it possible, in particular, to utilize the volume of the fraction collector's collection container in a surprisingly efficient manner. This allows for the previously outlined cost and handling advantages to be achieved.

[0121] Further cost and handling advantages can be achieved by preventing at least a portion of the composition containing the first solvent from being discharged into a collection vessel after it leaves the chromatography column. Preferably, compositions that do not contain valuable substances are discarded, generally by means of a control valve in the fraction collector that directs the portions of the composition containing the first solvent to be discarded into a waste container or similar receptacle after it leaves the chromatography column.

[0122] In a special embodiment, it may be provided that the solvent composition pumped into a chromatography column is changed during the course of the chromatography.

[0123] Preferably, the proportion of the first solvent in the solvent composition is increased during the chromatography process, and the proportion of the second solvent or fluid is decreased. Particularly preferably, the proportion of the first solvent at the beginning of the chromatography is at least 5 vol%, more preferably at least 10 vol%, and most preferably at least 20 vol% lower than the proportion of the first solvent at the end of the chromatography, based on the solvent composition. Accordingly, the proportion of solvent that is liquid under normal conditions preferably increases, while the proportion of solvent that is gaseous under normal conditions decreases. This configuration surprisingly minimizes, and preferably completely prevents, the formation of crusts in a gas separator used in a preferred embodiment of the process.This can surprisingly improve the separation quality of the system or process.

[0124] Furthermore, it may be provided that the proportion of the first solvent is in the range of 5 to 95 vol% and the proportion of the second solvent is in the range of 5 to 95 vol%, based on the solvent composition.

[0125] Preferably, the chromatography may be carried out at a pressure in the range of 50 to 500 bar, preferably 75 to 400 bar.

[0126] In a preferred embodiment, the chromatography can be carried out at a temperature in the range of 20°C to 80°C, preferably 35°C to 60°C.

[0127] In a preferred embodiment of an SFC, the second solvent contained in the composition downstream of the chromatography column can be at least partially separated before being introduced into the fraction collector. This can surprisingly result in a significant improvement in efficiency, since a portion of the solvent is separated before the fraction collector, thus reducing the frequency of vessel changes for the same volume of collection vessels.

[0128] The gas-liquid separator can generally be operated at atmospheric pressure. However, to prevent the accumulation of larger quantities of liquid, e.g., methanol, the gas-liquid separator can be operated at a moderate internal back pressure, for example, in the range of 0.1 bar to 25 bar, regulated by a back pressure regulator. Accordingly, the chromatography system can be provided with a back pressure regulator downstream of the gas outlet, preferably adjustable in the range of 1 bar to 25 bar gauge pressure (absolute pressure 2 bar to 21 bar), more preferably 2 bar to 15 bar gauge pressure. Depending on the system design, particularly when recovering the second fluid, e.g., CO2, higher back pressures can also be used, in the range of 20 to 60 bar, preferably in the range of 26 to 50 bar, and most preferably in the range of 30 to 40 bar (gauge pressure).The liquid component collected across the separation zone and supplied through the liquid outlet channel enables automated fractionation that can be operated at atmospheric pressure. Using the gas-liquid separator, and similar to conventional HPLC analysis, fully automated fraction collection can also be implemented for SFC analysis.

[0129] Accordingly, a gas-liquid separator may be used, wherein the pressure in the gas-liquid separator is preferably in the range of 0.1 to 25 bar, more preferably 0.5 to 20 bar, and particularly preferably 1 to 15 bar (gauge pressure). In a further embodiment, in which, for example, CO2 can be recovered, the pressure in the gas-liquid separator may be in the range of 20 to 60 bar, more preferably in the range of 26 to 50 bar, and particularly preferably in the range of 30 to 40 bar (gauge pressure).

[0130] This design allows for further surprising improvements. In particular, the transit time between the expansion of the solvent mixture and the outlet of the gas-liquid separator is essentially determined by the pressure drop. The gas generated in the small volume causes a high pressure, which is crucial for the transit time. The relative constancy of this pressure results in high signal integrity, as the transit time remains essentially constant even after expansion when using a suitable gas-liquid separator. Accordingly, especially when using a gas-liquid separator, which can preferably be operated at an overpressure, the addition of solvent, as previously required to ensure signal integrity, can be omitted.It should be noted that absolute constancy of the gas pressure in the gas-liquid separator is not necessary, as the transit time is very short even at relatively low pressures. Therefore, fluctuations have no significant impact on signal integrity, which is subject to normal fluctuations due to error tolerances. Thus, pressure fluctuations in the range of 0.1 bar to 25 bar in the gas-liquid separator lead to suitable results. Depending on the design, even higher pressures, for example up to 60 bar, preferably up to 50 bar, and particularly preferably up to 40 bar (gauge pressure), are possible. Preferred embodiments of suitable gas-liquid separators are described above and below, and reference is made to these descriptions.

[0131] In a preferred embodiment of the method, in which the chromatography system includes a back pressure regulator by which the pressure in the gas-liquid separator can be controlled, it can be provided that the control of the pressure is selected depending on the solvent content of the gas-liquid mixture; preferably, the control can be designed such that a high pressure is provided in the gas-liquid separator when the solvent content is high.

[0132] Preferably, the fractionation process can be operated at a lower pressure than the gas-liquid separator, with the pressure difference preferably being in the range of 0.1 to 60 bar, preferably 0.5 to 40 bar and particularly preferably 1 to 25 bar.

[0133] The fractionation is preferably carried out at a pressure in the range of 0 to 1 bar (gauge pressure), particularly preferably 0 to 0.5 bar, and especially preferably 0 to 0.2 bar. The pressure values ​​stated above refer to gauge pressure, which is measured relative to atmospheric pressure.

[0134] The detection of a fraction to be collected can be defined in the usual manner, which is generally also used in related chromatographic methods. This includes, for example, collecting a fraction at a specific signal level of the detector, such as a UVA / IS detector. Furthermore, a fraction can also be collected based on a specific signal shape, such as a predetermined change in the slope of the detector signal or a specific value of the detector signal slope.

[0135] Furthermore, the chromatography can be carried out at a flow rate in the range of 10 ml / min to 450 ml / min, particularly preferably in the range of 50 ml / min to 300 ml / min, and especially preferably 100 ml / min to 250 ml / min. This flow rate represents the total flow rate. The flow rate of the individual solvents, in particular the first and second solvents, which are each used as a mixture, is determined by their respective volume fractions.

[0136] Preferred embodiments of the present invention will now be described by way of example with reference to 18 figures, without thereby limiting the invention. The figures show:

[0137] Figure 1 shows a schematic representation of a chromatography system,

[0138] Figure 2 is a schematic representation of a preferably usable

[0139] Addition unit and a pump supply line switching valve in a switching position,

[0140] Figure 3 shows a schematic representation of a preferably usable addition unit and a pump supply line switching valve in a further switching position,

[0141] Figure 4 shows a schematic representation of a preferably usable addition unit and a pump supply line switching valve in a further switching position,

[0142] Figure 5 shows a schematic representation of a preferably used fraction collection device with a first fraction switching valve and a second fraction switching valve.

[0143] Figure 6 shows a schematic representation of a preferably used fraction collection device with a first fraction switching valve and a second fraction switching valve in a further switching position,

[0144] Figure 7 shows a schematic representation of a chromatography system designed as an SFC system,

[0145] Figure 8 shows a schematic representation of another preferably usable addition unit and a pump supply line switching valve in a switching position; Figure 9 shows a schematic representation of another preferably usable addition unit and a pump supply line switching valve in another switching position.

[0146] Figure 10 shows a schematic representation of another preferably usable addition unit and a pump supply line switching valve in a switching position,

[0147] Figure 11 shows a schematic representation of another preferably usable addition unit and a pump supply line switching valve in another switching position,

[0148] Figure 12 shows a schematic representation of another preferably usable addition unit and a pump supply line switching valve in another switching position,

[0149] Figure 13 shows a schematic representation of another preferably usable addition unit and a pump supply line switching valve in a switching position,

[0150] Figure 14 shows a schematic representation of another preferably usable addition unit and a pump supply line switching valve in another switching position,

[0151] Figure 15 shows a schematic representation of another preferably usable addition unit and a pump supply line switching valve in a switching position,

[0152] Figure 16 shows a schematic representation of another preferably usable addition unit and a pump supply line switching valve in another switching position,

[0153] Figure 17 shows a schematic representation of a preferably usable addition unit and a pump supply line switching valve in a further switching position, and

[0154] Figure 18 shows a schematic representation of a preferably usable addition unit and a pump supply line switching valve in a further switching position.

[0155] Figure 1 shows a schematic representation of a chromatography system 1, such as an HPLC system. A suitable chromatography system 1 comprises two fluid streams, a first fluid being supplied by a first liquid reservoir 3 and a second fluid by a second liquid reservoir 5. The two fluids are transferred from the liquid reservoirs 3, respectively, by a first pump 7 (comprising two pistons 7a and 7b) and a second pump 9 (also comprising two pistons 9a and 9b), into a connecting piece 11. A mixer 13 is provided downstream of the connecting piece 11 in the direction of flow. A mixer is not a necessary component of a chromatography system according to the invention. However, its inclusion can often yield surprising advantages.Downstream of mixer 13, a second connecting piece 15 is provided through which a sample can be fed into the chromatography system via an injection unit 17. A check valve 16 is provided between connecting piece 15 and injection unit 17 to prevent fluid from mixer 13 from entering the injection unit 17. The injection unit 17 comprises an injection valve 19 and a sample loop 21. The injection valve 19 is connected via lines to a pump supply control valve 23. A third pump 25 is provided in a line between the injection valve 19 and the pump supply control valve 23. Furthermore, the pump supply control valve 23 is connected to a liquid reservoir 27 for a third fluid and to a liquid reservoir 29 for a sample.

[0156] The switching positions and connections of the injection valve 19 and the pump supply line switching valve 23 are explained in more detail in Figures 2, 3, 4 and 8 to 16, to which reference is made here.

[0157] The first fluid is transferred from liquid reservoir 3 by a pump 7, and the second fluid from liquid reservoir 5 by a pump 9, into the previously described connecting piece 11, so that a composition is present downstream of the connecting piece 11. This composition is then mixed by a mixer 13 located downstream of the connecting piece 11 (viewed in the direction of flow). For clarification, it should be noted that the present chromatography system is suitable for performing chromatography in which only one fluid is used initially. Therefore, the term "composition" is to be interpreted broadly and is used here only as an example. After the mixer 13, a sample is added to the composition. This sample is transferred via the second connecting piece 15 with the addition unit 17, in conjunction with the third pump 25 and the pump supply control valve 23, into the chromatography column 31.A fraction collection device 33 is preferably provided after the chromatography column 31.

[0158] The fraction collection device 33 can be controlled by one or more control units (not shown here), which are operatively connected to one or more detectors. The detectors are located between the chromatography column 31 and the fraction collection device 33, viewed in the direction of flow.

[0159] The term faction collection device 33 herein includes a conventional faction collector with many smaller collection vessels as well as a device, as further explained in Figures 5 and 6, which includes several larger collection vessels.

[0160] Figure 2 describes a preferably usable pump supply switching valve 40 and an addition unit 49 with an injection valve 50 in a switching position in which the sample loop 51 is loaded.

[0161] Figure 2 shows a pump supply line switching valve 40 with eight ports (41, 42, 43, 44, 45, 46, 47, 48), with ports (42, 45) marked with the symbol "X" being closed. Port 41 serves to release pressure from a pressurized fluid, in particular a third fluid, so that a preferred embodiment of a pump supply line switching valve is shown here. Port 44 is connected to a sample container 38, port 46 to a liquid reservoir 37 for a third fluid, and port 47 to an inlet line of a third pump 36.

[0162] The outlet line of the third pump 36 is connected to a high-pressure port 52 of the injection valve 50. The injection valve 50 comprises six ports (52, 53, 54, 55, 56, 57), with two ports (54, 57) configured as sample loop ports, two ports (52, 53) as high-pressure ports for supplying and discharging high-pressure fluid, and two ports (55, 56) as ports for supplying and discharging sample composition and / or fluid into and out of the sample loop. Ports 54 and 57 are connected to the sample loop 51 and configured as sample loop ports. Ports 52 and 53 serve as high-pressure ports for supplying and discharging high-pressure fluid, with port 52 being connected to the outlet line of the third pump 36 and port 53 allowing the sample to be transferred to the chromatography column, which can be done via a second connecting piece, as shown in more detail in Figure 1.The ports 55, 56 of the injection valve 50 are connected to ports 43 and 48 of the pump supply line switching valve, so that a sample can be introduced into the sample loop 51 via these ports 55 and 56 and fluid can be discharged from the sample loop.

[0163] In one switching position of the pump supply valve 40, the inlet line of the third pump 36 is connected to a sample loop port 56 of the addition unit 49, as is explained in more detail below. This switching position of the injection valve 50 is also referred to herein as the first switching position of the injection valve, and that of the pump supply valve 40 as the second switching position of the pump supply valve.

[0164] In this first switching position of the injection valve 50 of the addition unit 49, the sample loop ports (55, 56) for loading the sample loop 51 are connected to the two sample loop ports (54, 57), and in the second switching position of the pump supply line switching valve 40, port 44, to which the sample container 38 is connected, is connected to port 43, and port 47, to which the inlet line of the third pump 36 is connected, is connected to port 48, with ports 43 and 48 of the pump supply line switching valve 40 being connected to ports 55 and 56 respectively of the injection valve 50.

[0165] In this switching position, a sample can be introduced into the sample loop 51. In this switching position, port 44 is connected to port 43 of the pump supply line switching valve 40. Furthermore, in the injection valve, port 54 is connected to port 55 and port 56 to port 57. The third pump 36 accordingly draws a sample from sample container 38 into the sample loop 51 via ports 44, 43, 55, and 54, whereby a fluid previously located in the sample loop 51, for example, a third fluid or solvent, is conveyed via ports 57, 56, 48, and 47 into the inlet line of the third pump 36. After the sample loop 51 has been loaded, the valves are switched for sample injection, as shown in Figure 3. This switching is preferably coordinated.

[0166] Figure 3 schematically describes a preferably usable pump supply switching valve 40 and an injection unit 49 with an injection valve 50 in a switching position in which the sample is applied from the sample loop 51 into the chromatography column. As described in Figure 2, the injection unit 49 comprises an injection valve 50 and a sample loop 51, wherein the injection valve 50 has six ports (52, 53, 54, 55, 56, 57). Furthermore, Figure 3 shows a pump supply switching valve 40 with eight ports (41, 42, 43, 44, 45, 46, 47, 48), which is connected to other components, such as a third pump 36, a liquid reservoir 37 for a third fluid, and a sample container 38. These components have been described in more detail previously, with identical reference numerals representing the same components, so reference is made to Figure 2 for a description of these components.

[0167] In Figure 3, the injection valve 50 is in a further switching position in which a sample from the sample loop 51 is applied to a chromatography column. This switching position of the injection valve 50 is also referred to here as the second switching position of the injection valve, and the further position of the pump supply line switching valve 40 is referred to as the first switching position of the pump supply line switching valve. In this switching position of the pump supply line switching valve 40, the inlet line of the third pump 36 is connected to a liquid reservoir 37 for a third fluid, as is explained in more detail below. The injection valve 50 is switched such that a sample from sample loop 51 is applied to a chromatography column (not shown).

[0168] In this second switching position of the injection valve 50 of the addition unit 49, the high-pressure ports (52, 53) for supplying and discharging high-pressure fluid are connected to the two sample loop ports (54, 57), with port 52 connected to port 57 and port 54 to port 53. In the first switching position of the pump supply switching valve 40, port 46, to which the liquid reservoir 37 for a third fluid is connected, is connected to port 47, to which the inlet line of the third pump 36 is connected.

[0169] In this switching position of the injection valve 50, a third fluid is pumped by the pump 36 into port 52, so that this fluid transfers a sample from sample loop 51 via port 54 into port 53 through port 57, which is connected to port 52. Port 53 allows the sample to be transferred into the chromatography column, which can be done via a second connecting piece, as shown in more detail in Figure 1.

[0170] Figure 4 describes another combination of the switching positions of the pump supply line switching valve 40 and the injection valve 50. In the position combination shown in Figure 4, the pump supply line switching valve 40 is in the first switching position, in which fluid is drawn into the inlet line of the third pump and pumped into port 52 of the injection valve 50. The injection valve 50 of the addition unit 49 is switched in a first switching position, with the two high-pressure ports (52, 53) connected for supplying and discharging high-pressure fluid.

[0171] In the switching position of the injection valve 50, port 56 is connected to port 57 and port 54 to port 55, with ports 55 and 56 being connected to ports 43 and 48 of the pump supply switching valve 40. In this switching position of the pump supply switching valve 40, ports 41 and 48 are connected, with port 41 serving to depressurize the fluid under pressure in the sample loop 51. During the injection process shown in Figure 3, pressure is built up in the sample loop 51 by the pumped third fluid. In the switching position shown in Figure 2, this pressure could cause the third fluid, which is located in the sample loop 51, to be transferred, at least partially, into the sample container 38 or sample feeder 59. This can lead to an undesirable dilution of the sample located in the sample container 38 or sample feeder 59. Port 41 can be connected to a container to collect fluid.Furthermore, Figure 4 describes a further development of the embodiments shown in Figures 2 and 3. In addition to the components described above, this embodiment includes a system 58 for flushing a sample feeder 59, wherein the sample feeder 59 can be connected to a sample container in a flow-through connection. Preferably, the sample feeder can sequentially extract samples from two or more sample containers, so that flushing of the sample feeder is advantageously carried out when the sample containers are changed. This is explained in more detail below. This can be done in the first switching position of the pump supply valve 40, wherein a fluid, preferably a third fluid, is pumped into the sample feeder 59 via ports 45 and 44.

[0172] Figure 5 shows a schematic representation of a preferably used fraction collection device with a first fraction switching valve and a second fraction switching valve in a switching position in which a fraction from a chromatography column is directed into the second fraction switching valve.

[0173] Figure 5 shows a preferred fraction collection device 61 with a first fraction switching valve 63, wherein the first fraction switching valve 63 comprises six ports (65, 66, 67, 68, 69, 70). Port 66 of the first fraction switching valve 63 is connected to a second fraction switching valve 72, and port 64 to a chromatography column 84. Depending on the configuration of the chromatography system, further components thereof may be provided between the chromatography column and port 65, such as detectors and, in the case of SFC, a back pressure regulator and a gas-liquid separator, which are not present in HPLC. Depending on the configuration of the system, port 70 is connected to a fraction collector 82, which preferably comprises a plurality of smaller collection vessels, or to a waste collection vessel 82. Port 67 is connected to the outlet line of a flushing pump 86, which in turn is connected to a fluid reservoir.In the present embodiment, port 68 of the first fraction switching valve 63 is connected to a port of a pump supply switching valve, which is not shown.

[0174] In the switching position of the first fraction switching valve 63 shown in Figure 5, a fluid pumped by the flushing pump 86 via port 67 and port 68 can be used to flush the sample feeder shown in Figure 4, so that reference is made to this and the flushing pump 86 shown in Figure 5 can serve as a system for flushing a sample feeder.

[0175] The second fraction switching valve 72 comprises an inlet port 74, which is connected to port 66 of the first fraction switching valve 63 and through which fluid can be directed from the first fraction switching valve 63 into the second fraction switching valve 72. Furthermore, the second fraction switching valve 72 comprises several outlet ports 76, each connected to a preferably large collection vessel 78, through which fractions can be collected. For clarity, only one collection vessel 78 is shown, but a plurality of outlet ports 76. In the present illustration, a fraction to be collected is directed into the collection vessel 78 via the inlet port 74. To collect the next fraction, the second fraction switching valve 72 can be switched so that the fraction is directed into another collection vessel (not shown).

[0176] In the switching position of the first fraction switching valve 63 shown here, fluid which is directed from the chromatography column 84 via port 65 into the first fraction switching valve 63 is transferred via port 66 into port 74 of the second fraction switching valve 72 and via port 76 into a collection vessel 78.

[0177] In this switching position, port 67 is connected to port 68, so that the flushing pump 86 can be used to flush a sample feeder, as shown in Figure 4.

[0178] Figure 6 shows a schematic representation of a preferably used fraction collection device with a first fraction switching valve and a second fraction switching valve in a further switching position, in which a fraction from a chromatography column is directed into a fraction collector or a waste collection container.

[0179] The components shown in Figure 6 are essentially the same as those shown in Figure 5, with the same reference numerals describing the same components. In the switching position of the first fraction switching valve 63 shown in Figure 6, fluid that is fed from the chromatography column 84 into the first fraction switching valve 63 via port 65 is transferred via port 70 into a fraction collector or a waste container 82.

[0180] In this switching position, port 67 is connected to port 66, so that the flushing pump 86 can be used to flush the second fraction switching valve 72, starting from port 67 of the first fraction switching valve 63 to the respective connected collection vessel 78.

[0181] The fraction collection device 61 shown in Figures 5 and 6 can preferably be used to advantage in two operating modes, which are described below.

[0182] In a first operating mode, this fraction collection device 61 enables the efficient use of large collection containers 78, such as those connected to the second fraction switching valve 72. Typically, when using large collection containers, waste fractions are collected between the containers for valuable fractions.

[0183] In the first operating mode, the fraction collection device 61 shown allows waste fractions to be directed into a waste collection vessel 82 via the switching position of the first fraction switching valve 63 shown in Figure 6. In this position, the line can be flushed with fluid starting from port 67 of the first fraction switching valve 63, so that when the next position for collecting a valuable fraction is reached, no residues remain in the line between port 66 of the first fraction switching valve 63 and the next collection vessel 78, and these can be directed into the next collection vessel 78, as shown in Figure 5.

[0184] In a second operating mode, this fraction collection device 61 allows fractions to be collected between the valuable fractions in order to test them again before discarding the waste fraction. This is particularly useful if complex detection systems are not available.

[0185] In a second operating mode, valuable fractions are directed into a fraction collector 82 in the switching position of the first fraction switching valve 63 shown in Figure 6. In this position, the line can be flushed with fluid starting from port 67 of the first fraction switching valve 63 to prevent cross-contamination between possible waste fractions. In the switching position shown in Figure 5, different waste fractions are directed into the second fraction switching valve 72 and from there transferred into different collection containers 78.

[0186] Figure 7 shows a schematic representation of a chromatography system 100 with a gas-liquid separator 130, which is suitable for supercritical liquid chromatography.

[0187] Such a system is described using supercritical CO2 as an example, with methanol being presented as an exemplary solvent. Naturally, systems using other solvents, preferably organic solvents, or other supercritical fluids, are similarly constructed.

[0188] As shown in Fig. 7, the respective fluids are stored in reservoirs. In particular, the gas used in a supercritical state can be stored in a storage tank 102, and the solvent in a storage tank 104. These fluids can be pumped from storage tanks 102 and 104 to the other components of the system via pumps 106 and 108, respectively. In the system 100 described here, a preparation stage 110 or 112 is preferably provided in each fluid supply line, through which the liquids can be tempered. Furthermore, a leveling stage for pressure fluctuations caused by the pumps can be provided. Accordingly, this preparation stage can be designed, for example, as a heat exchanger or as a pump. The fluids taken from storage tanks 102 and 104 are directed into a connecting piece 114 and subsequently into a mixer 115.

[0189] Downstream of the mixer, a second connecting piece 116 is provided, through which a sample can be supplied to the chromatography system 100, which is then applied to the chromatography column 120. Reference numeral 117 symbolizes a dosing unit, a preferred embodiment of which is shown in more detail in Figures 2, 3, and 4 and may include further components, including a third pump whose inlet line can be switched via a pump inlet control valve. These components are not shown in detail here for the sake of clarity, so reference is made to the figures shown above. The liquid reservoir 118 for a third fluid and a sample container 119 are in fluid connection with the components shown by reference numeral 117, as described in detail in Figures 2, 3, and 4 above.

[0190] In the present system 100, two analysis units are connected downstream of the chromatography column 120. A sample discharge unit 121 is connected to a mass spectrometer 122, and a UV detector 124 is provided downstream of the sample discharge unit. Downstream of the analysis unit, a device for providing an additional volume 125 is provided, which serves in particular to increase the flow time of the liquid in order to evaluate results, for example, from the mass spectrometer 122. The backpressure regulator 126 provided in the line downstream of the device for providing the additional volume 125 maintains the respective pressure necessary to keep the fluid in a supercritical state. A heat exchanger 128 is provided downstream of the backpressure regulator 126, which prevents the aerosol from freezing during the decompression process.The aerosol is then introduced into a gas-liquid separator 130, with the gas from the system being discharged via outlet 132.

[0191] The liquid is introduced into a fraction collector or fraction collection device 134 and fractionated therein. The solvent contained in the fractionated samples can be removed from the samples.

[0192] Figure 8 describes another preferably usable pump supply switching valve 140 and an addition unit 139 with an injection valve 50 in a switching position in which the sample loop 51 is loaded.

[0193] Figure 8 shows a pump supply line switching valve 140 with four ports (142, 144, 146, 148). It is obvious to those skilled in the art that a valve with more ports can also be used, in which case ports must be closed or connected to each other in a suitable manner. Port 146 serves to depressurize pressurized fluid, in particular a third fluid, so that a preferred embodiment of a pump supply line switching valve is shown here. Port 148 is connected to a fluid reservoir 137 for a third fluid, and port 142 is connected to an inlet line of a third pump 136.

[0194] The outlet line of the third pump 136 is connected to a high-pressure port 52 of the injection valve 50. The injection valve 50 comprises six ports (52, 53, 54, 55, 56, 57), with two ports (54, 57) configured as sample loop ports, two ports (52, 53) as high-pressure ports for supplying and discharging high-pressure fluid, and two ports (55, 56) as ports for supplying and discharging sample composition and / or fluid into and out of the sample loop. Ports 54 and 57 are connected to the sample loop 51 and configured as sample loop ports. Ports 52 and 53 serve as high-pressure ports for supplying and discharging high-pressure fluid, with port 52 being connected to the outlet line of the third pump 36 and port 53 allowing the sample to be transferred to the chromatography column, which can be done via a second connecting piece, as shown in more detail in Figure 1.Port 55 of the injection valve 50 is connected to a sample container 138 and port 56 of the injection valve is connected to port 144 of the pump supply line switching valve, so that a sample can be introduced into the sample loop 51 via these ports 55 and 56 and fluid can be discharged from the sample loop.

[0195] In one switching position of the pump supply line switching valve 140, the inlet line of the third pump 136 is connected to a sample loop port 56 of the addition unit 139, as is explained in more detail below. This switching position of the injection valve 50 is also referred to here as the first switching position of the injection valve, and that of the pump supply line switching valve 140 as the second switching position of the pump supply line switching valve.

[0196] In this first switching position of the injection valve 50 of the addition unit 139, the sample loop ports (55, 56) for loading the sample loop 51 are connected to the two sample loop ports (54, 57) and in the second switching position of the pump supply line switching valve 140, port 142, to which the inlet line of the third pump 36 is connected, is connected to port 144, to which port 56 of the injection valve is connected.

[0197] In this switching position, a sample can be introduced into the sample loop 51. In this switching position, port 142 is connected to port 144 of the pump supply line switching valve 140. Furthermore, in the injection valve, port 54 is connected to port 55 and port 56 to port 57. Accordingly, the third pump 136 draws a sample from sample container 138 into the sample loop 51 via ports 55 and 54, whereby a fluid previously located in the sample loop 51, for example, a third fluid or solvent, is conveyed via ports 57, 56, 144, and 142 into the inlet line of the third pump 136.

[0198] After loading the sample loop 51, the valves for sample injection are switched as shown in Figure 9. This switching is preferably coordinated.

[0199] Figure 9 schematically depicts a preferably usable pump supply switching valve 140 and an addition unit 139 with an injection valve 50 in a switching position in which the sample is applied from the sample loop 51 to the chromatography column. As described in Figure 8, the addition unit 139 comprises an injection valve 50 and a sample loop 51, wherein the injection valve 50 has six ports (52, 53, 54, 55, 56, 57). Furthermore, Figure 9 shows a pump supply switching valve 140 with four ports (142, 144, 146, 148), which is connected to other components, such as a third pump 136 and a liquid reservoir 137 for a third fluid. These components have been described in more detail previously, with identical reference numerals representing the same components, so reference is made to Figure 8 for a description of these components.

[0200] In Figure 9, the injection valve 50 is in a further switching position in which a sample from the sample loop 51 is applied to a chromatography column. This switching position of the injection valve 50 is also referred to here as the second switching position of the injection valve, and the further position of the pump supply line switching valve 140 is referred to as the first switching position of the pump supply line switching valve. In this switching position of the pump supply line switching valve 140, the inlet line of the third pump 136 is connected to a liquid reservoir 137 for a third fluid, as is explained in more detail below. The injection valve 50 is switched such that a sample from sample loop 51 is applied to a chromatography column (not shown).

[0201] In this second switching position of the injection valve 50 of the addition unit 139, the high-pressure ports (52, 53) for supplying and discharging high-pressure fluid are connected to the two sample loop ports (54, 57), with port 52 connected to port 57 and port 54 to port 53. In the first switching position of the pump supply switching valve 140, port 148, to which the liquid reservoir 137 for a third fluid is connected, is connected to port 142, to which the inlet line of the third pump 136 is connected.

[0202] In this switching position of the injection valve 50, a third fluid is pumped by the pump 136 into port 52, so that this fluid transfers a sample from sample loop 51 via port 54 into port 53 through port 57, which is connected to port 52. Port 53 allows the sample to be transferred into the chromatography column, which can be done via a second connecting piece, as shown in more detail in Figure 1.

[0203] Figure 10 describes another combination of the switching positions of the pump supply line switching valve 140 and the injection valve 50. In the position combination shown in Figure 10, the pump supply line switching valve 140 is in the first switching position, in which third fluid is drawn into the inlet line of the third pump and pumped into port 52 of the injection valve 50. The injection valve 50 of the addition unit 139 is switched in a first switching position, with the two high-pressure ports (52, 53) connected for supplying and discharging high-pressure fluid.

[0204] In the switching position of the injection valve 50, port 56 is connected to port 57 and port 54 to port 55, with port 55 being connected to a sample container 138 and port 56 to port 144 of the pump supply switching valve 140. In this switching position of the pump supply switching valve 140, ports 144 and 146 are connected, with port 146 serving to depressurize the fluid under pressure in the sample loop 51. During the injection shown in Figure 9, pressure is built up in the sample loop 51 by the pumped third fluid. In the switching position shown in Figure 8, this pressure could cause the third fluid, which is located in the sample loop 51, to be at least partially transferred into the sample container 138. This can lead to an undesirable dilution of the sample in the sample container 138. Port 146 can be connected to a container to collect fluid.

[0205] Figure 11 describes another preferably usable pump supply switching valve 160 and an addition unit 139 with an injection valve 50 in a switching position in which the sample loop 51 is loaded.

[0206] Figure 11 shows a pump supply line switching valve 160 with three ports (162, 164, 166). Port 166 is connected to a fluid reservoir 137 for a third fluid, and port 162 is connected to an inlet line of a third pump 136.

[0207] The outlet line of the third pump 136 is connected to a high-pressure port 52 of the injection valve 50. The injection valve 50 comprises six ports (52, 53, 54, 55, 56, 57), with two ports (54, 57) configured as sample loop ports, two ports (52, 53) as high-pressure ports for supplying and discharging high-pressure fluid, and two ports (55, 56) as ports for supplying and discharging sample composition and / or fluid into and out of the sample loop. Ports 54 and 57 are connected to the sample loop 51 and configured as sample loop ports. Ports 52 and 53 serve as high-pressure ports for supplying and discharging high-pressure fluid, with port 52 being connected to the outlet line of the third pump 136 and port 53 allowing the sample to be transferred to the chromatography column, which can be done via a second connecting piece, as shown in more detail in Figure 1.Port 55 of the injection valve 50 is connected to a sample container 138 and port 56 of the injection valve is connected to port 164 of the pump supply line switching valve, so that a sample can be introduced into the sample loop 51 via these ports 55 and 56 and fluid can be discharged from the sample loop.

[0208] In one switching position of the pump supply line switching valve 160, the inlet line of the third pump 136 is connected to a sample loop port 56 of the addition unit 138, as is explained in more detail below. This switching position of the injection valve 50 is also referred to herein as the first switching position of the injection valve, and that of the pump supply line switching valve 160 as the second switching position of the pump supply line switching valve.

[0209] In this first switching position of the injection valve 50 of the addition unit 139, the sample loading ports (55, 56) for loading the sample loop 51 are connected to the two sample loop ports (54, 57) and in the second switching position of the pump supply line switching valve 160, port 162, to which the inlet line of the third pump 136 is connected, is connected to port 164, to which port 56 of the injection valve is connected.

[0210] In this switching position, a sample can be introduced into the sample loop 51. In this switching position, port 162 is connected to port 164 of the pump supply switching valve 160. Furthermore, in the injection valve, port 54 is connected to port 55 and port 56 to port 57. Accordingly, the third pump 136 draws a sample from sample container 138 into the sample loop 51 via ports 55 and 54, whereby a fluid previously located in the sample loop 51, for example, a third fluid or solvent, is conveyed via ports 57, 56, 164, and 162 into the inlet line of the third pump 136.

[0211] After loading the sample loop 51, the valves for sample injection are switched as shown in Figure 12. This switching is preferably coordinated.

[0212] Figure 12 schematically depicts a preferably usable pump supply switching valve 160 and an addition unit 139 with an injection valve 50 in a switching position in which the sample is applied from the sample loop 51 to the chromatography column. As described in Figure 11, the addition unit 139 comprises an injection valve 50 and a sample loop 51, wherein the injection valve 50 has six ports (52, 53, 54, 55, 56, 57). Furthermore, Figure 12 shows a pump supply switching valve 160 with three ports (162, 164, 166), which is connected to other components, such as a third pump 136 and a liquid reservoir 137 for a third fluid. These components have been described in more detail previously, with identical reference numerals representing the same components, so reference is made to Figure 11 for a description of these components.In Figure 12, the injection valve 50 is in a further switching position in which a sample from the sample loop 51 is applied to a chromatography column. This switching position of the injection valve 50 is also referred to here as the second switching position of the injection valve, and the further position of the pump supply line switching valve 160 is referred to as the first switching position of the pump supply line switching valve. In this switching position of the pump supply line switching valve 160, the inlet line of the third pump 136 is connected to a liquid reservoir 137 for a third fluid, as is explained in more detail below. The injection valve 50 is switched such that a sample from sample loop 51 is applied to a chromatography column (not shown).

[0213] In this second switching position of the injection valve 50 of the addition unit 139, the high-pressure ports (52, 53) for supplying and discharging high-pressure fluid are connected to the two sample loop ports (54, 57), with port 52 connected to port 57 and port 54 to port 53. In the first switching position of the pump supply switching valve 160, port 166, to which the liquid reservoir 137 for a third fluid is connected, is connected to port 162, to which the inlet line of the third pump 136 is connected.

[0214] In this switching position of the injection valve 50, a third fluid is pumped by the pump 136 into port 52, so that this fluid transfers a sample from sample loop 51 via port 54 into port 53 through port 57, which is connected to port 52. Port 53 allows the sample to be transferred into the chromatography column, which can be done via a second connecting piece, as shown in more detail in Figure 1.

[0215] Figure 13 describes a preferably usable pump supply switching valve 240 and an addition unit 249 with an injection valve 250 in a switching position in which the sample loop 251 is loaded.

[0216] Figure 13 shows a pump supply line switching valve 240 with eight ports (241, 242, 243, 244, 245, 246, 247, 248), with port (242) marked with the symbol "X" being closed. Port 241 serves to release pressure from a pressurized fluid, in particular a third fluid, so that a preferred embodiment of a pump supply line switching valve is shown here. Port 244 is connected to a sample feeder 280, port 246 to a liquid reservoir 237 for a third fluid, and port 247 to an inlet line of a third pump 236. Sample feeder 290 can comprise several sample containers (not shown in detail) from which different samples can be supplied to the chromatography system via a sampling needle. Furthermore, the embodiment presented here includes a system 280 for rinsing the sample feed 290, which is connected to the pump supply switching valve 240 via port 245.

[0217] The outlet line of the third pump 236 is connected to a high-pressure port 253 of the injection valve 250. The injection valve 250 comprises 8 ports (252, 253, 254, 255, 256, 257, 258, 259), with two ports (252, 255) being designed as sample loop ports, two ports (253, 254) as high-pressure ports for supplying and discharging high-pressure fluid, and two ports (256, 259) as ports for supplying and discharging sample composition and / or fluid into and out of the sample loop. The ports marked with the symbol "X" (257, 258) are closed.

[0218] Ports 252 and 255 are connected to the sample loop 251 and configured as sample loop ports. Ports 253 and 254 serve as high-pressure ports for supplying and discharging high-pressure fluid. Port 253 is connected to the outlet line of the third pump 236, and port 254 allows the sample to be transferred to the chromatography column via a second connection, as shown in more detail in Figure 1. Ports 256 and 259 of the injection valve 250 are connected to ports 243 and 248 of the pump supply switching valve 240, so that a sample can be introduced into the sample loop 251 and fluid can be discharged from the sample loop via these ports 256 and 259.

[0219] In one switching position of the pump supply line switching valve 240, the inlet line of the third pump 236 is connected to a sample loop port 256 of the addition unit 249, as is explained in more detail below. This switching position of the injection valve 250 is also referred to herein as the first switching position of the injection valve, and that of the pump supply line switching valve 240 as the second switching position of the pump supply line switching valve.In this first switching position of the injection valve 250 of the addition unit 249, the sample loading ports (256, 259) for loading the sample loop 251 are connected to the two sample loop ports (252, 255), and in the second switching position of the pump supply switching valve 240, port 244, to which the sample feeder 290 is connected, is connected to port 243, and port 247, to which the inlet line of the third pump 236 is connected, is connected to port 248, with ports 243 and 248 of the pump supply switching valve 40 being connected to ports 256 and 259 respectively of the injection valve 250.

[0220] In this switching position, a sample can be introduced into the sample loop 251. In this switching position, port 244 is connected to port 243 of the pump supply switching valve 240. Furthermore, in the injection valve, port 256 is connected to port 255 and port 252 to port 259. Accordingly, the third pump 36 draws a sample from sample feeder 290 into the sample loop 251 via ports 244, 243, 256, and 255, whereby a fluid previously located in the sample loop 251, for example, a third fluid or solvent, is conveyed via ports 252, 259, 248, and 247 into the inlet line of the third pump 236.

[0221] In addition to the components described above, this embodiment includes a system 280 for rinsing a sample feeder 290, wherein the sample feeder 290 can be brought into flow connection with a sample container.

[0222] Preferably, the sample feeder can sequentially extract samples from two or more sample containers, so that flushing of the sample feeder is advantageously carried out when changing the sample containers. This is explained in more detail below. This can take place in the first switching position of the pump supply valve 240, whereby a fluid, preferably a third fluid, is pumped into the sample feeder 290 via ports 245 and 244.

[0223] After loading the sample loop 251, the valves for sample injection are switched as shown in Figure 14. This switching is preferably coordinated.

[0224] Figure 14 schematically depicts a preferably usable pump supply switching valve 240 and an injection unit 249 with an injection valve 250 in a switching position in which the sample is applied from the sample loop 251 to the chromatography column. As described in Figure 13, the injection unit 249 comprises an injection valve 250 and a sample loop 251, wherein the injection valve 250 includes eight ports (252, 253, 254, 255, 256, 257, 258, 259). Furthermore, Figure 14 shows a pump supply switching valve 240 with eight ports (241, 242, 243, 244, 245, 246, 247, 248) which is connected to other components, such as a third pump 236, a liquid reservoir 237 for a third fluid, a system 280 for rinsing a sample feeder 290 and a sample feeder 290.These components have been described in more detail previously, with identical reference symbols representing the same components, so reference is made to Figure 13 for a description of these components.

[0225] In Figure 14, the injection valve 250 is in a further switching position in which a sample from the sample loop 251 is applied to a chromatography column. This switching position of the injection valve 250 is also referred to here as the second switching position of the injection valve, and the further position of the pump supply line switching valve 240 is referred to as the first switching position of the pump supply line switching valve. In this switching position of the pump supply line switching valve 240, the inlet line of the third pump 236 is connected to a liquid reservoir 237 for a third fluid, as is explained in more detail below. The injection valve 250 is switched such that a sample from sample loop 251 is applied to a chromatography column (not shown).

[0226] In this second switching position of the injection valve 250 of the addition unit 249, the high-pressure ports (253, 254) for supplying and discharging high-pressure fluid are connected to the two sample loop ports (252, 255), with port 253 connected to port 252 and port 254 to port 255. In the first switching position of the pump supply switching valve 240, port 246, to which the liquid reservoir 237 for a third fluid is connected, is connected to port 247, to which the inlet line of the third pump 236 is connected.

[0227] In this switching position of the injection valve 250, a third fluid is pumped by the pump 236 into port 253, so that this fluid transfers a sample from sample loop 251 via port 255 into port 254 through port 252, which is connected to port 253. Port 254 allows the sample to be transferred into the chromatography column, which can be done via a second connecting piece, as shown in more detail in Figure 1.

[0228] Figure 15 describes another combination of the switching positions of the pump supply switching valve 240 and the injection valve 250.

[0229] As described in Figure 13, the addition unit 249 comprises an injection valve 250 and a sample loop 251, wherein the injection valve 250 comprises eight ports (252, 253, 254, 255, 256, 257, 258, 259). Furthermore, Figure 15 shows a pump supply switching valve 240 with eight ports (241, 242, 243, 244, 245, 246, 247, 248), which is connected to other components, such as a third pump 236, a liquid reservoir 237 for a third fluid, a system 280 for rinsing a sample feeder 290, and a sample feeder 290. These components have been described in more detail previously, with identical reference numerals representing the same components, so reference is made to Figure 13 for a description of these components.

[0230] In the position combination shown in Figure 15, the pump supply line switching valve 240 is in the first switching position, in which third fluid is drawn into the inlet line of the third pump and pumped into port 253 of the injection valve 250. The injection valve 250 of the addition unit 249 is switched in a first switching position, with the two high-pressure ports (253, 254) for supplying and discharging high-pressure fluid being connected to each other.

[0231] In the switching position of the injection valve 250, port 252 is connected to port 259 and port 255 to port 256, with ports 259 and 256 being connected to ports 243 and 248 of the pump supply switching valve 240. In this switching position of the pump supply switching valve 240, ports 241 and 248 are connected, with port 241 serving to depressurize the fluid under pressure in the sample loop 251. During the injection process shown in Figure 14, pressure is built up in the sample loop 251 by the pumped third fluid. In the switching position shown in Figure 13, this pressure could cause the third fluid, which is located in the sample loop 251, to be at least partially transferred into the sample feed 290. This can lead to an undesirable dilution of the sample in the sample feed 290. Port 241 can be connected to a container to collect fluid.

[0232] Furthermore, in the first switching position of the pump supply switching valve 240, a flushing can take place, whereby a fluid, preferably a third fluid, is pumped into the sample feed 290 via ports 245 and 244.

[0233] Figure 16 describes another combination of the switching positions of the pump supply switching valve 240 and the injection valve 250.

[0234] As described in Figure 13, the addition unit 249 comprises an injection valve 250 and a sample loop 251, wherein the injection valve 250 comprises eight ports (252, 253, 254, 255, 256, 257, 258, 259). Furthermore, Figure 16 shows a pump supply switching valve 240 with eight ports (241, 242, 243, 244, 245, 246, 247, 248), which is connected to other components, such as a third pump 236, a liquid reservoir 237 for a third fluid, a system 280 for rinsing a sample feeder 290, and a sample feeder 290. These components have been described in more detail previously, with identical reference numerals representing the same components, so reference is made to Figure 13 for a description of these components.

[0235] In the position combination shown in Figure 16, the pump supply line switching valve 240 is in the second switching position, with the inlet line of the third pump 236 connected to a sample loop port 259 of the addition unit 249. The injection valve 250 of the addition unit 249 is switched in a second switching position, with the high-pressure ports (253, 254) for supplying and discharging high-pressure fluid connected to the two sample loop ports (252, 255), with port 253 connected to port 252 and port 254 to port 255.

[0236] In the switching position of the injection valve 250, port 252 is connected to port 253 and port 255 to port 254. Furthermore, port 259 is connected to port 258 and port 257 to port 256. Ports 241 and 242 are connected in this switching position of the pump supply switching valve 240. Furthermore, port 243 is connected to 244, port 247 to port 248, and port 246 to port 245. Ports 242, 258, and 257 are closed. It should be noted that in this combination of switching positions of both valves, each with eight ports, as shown in Figure 16, the third pump 236 is switched off because port 258 is closed. Therefore, after a short time, the position combination of the switching positions of both valves shown in Figure 15, which is particularly useful for releasing a fluid located in the sample loop 251, is usually switched to the position combination of the switching positions of both valves shown in Figure 16, preferably in a coordinated manner.The third pump, 236, is also switched off in this process.

[0237] The use of an injection valve with eight ports leads to surprising improvements. This applies particularly to the yield of purified substances and the purity of the purified substances. It should be noted that in the position combination of the switching positions of both valves shown in Figure 13, sample is present in the line between ports 243 and 256, which is transferred to sample loop 251. In the situation shown in Figure 3, port 56 of the injection valve 51 is connected to port 48 of the pump supply line switching valve 40, with a third fluid present in the line between these two ports. This fluid is introduced into sample loop 51 by injection and, during loading, is transferred from the sample loop 51 into the line section between ports 56 and 48.Since, in the position combination of the switching positions of both valves shown in Figure 3, the line section between port 43 and port 55 is connected to the line section between port 56 and port 48, diffusion from both line sections can lead to dilution of the sample located in the line between port 43 and port 55. Furthermore, diffusion processes can introduce sample into the line section between port 56 and port 48. This fluid is unintentionally deposited onto the chromatography column when the sample loop 51 is loaded. This can lead to these unintentionally deposited substances being washed off the chromatography column at an undefined time, potentially resulting in contamination.

[0238] It is clear that this point is of minor importance for many applications, so no effects are noticeable in many chromatographic processes. This is especially true if an identical sample is always applied, which is to be purified in smaller portions over several chromatographic runs. Furthermore, diffusion depends on the cross-sectional area of ​​the lines or ports, which are often small, and on the duration of the chromatography. However, unexpected advantages can be achieved in very large-scale chromatographic processes.

[0239] In the position combination of the switching positions of both valves shown in Figure 16, the line between port 243 and port 256 is separated from the line between port 259 and port 248. This ensures that no cross-contamination occurs when applying different samples or that a sample located in the line between port 243 and port 256 is not diluted.

[0240] Figure 17 shows a pump supply line switching valve 300 with eight ports (301, 302, 303, 304, 305, 306, 307, 308). Port 301 serves to release pressure from a pressurized fluid, in particular a third fluid, so that a preferred embodiment of a pump supply line switching valve is shown here. Furthermore, port 302 is connected to a flushing system, as will be explained later, so that the sample loop 320 can be flushed via port 301. Port 304 is connected to a sample container 324, port 305 to a system 328 for flushing a sample feeder, port 306 to a liquid reservoir 326 for a third fluid, and port 307 to an inlet line of a third pump 322.

[0241] The outlet line of the third pump 322 is connected to a high-pressure port 314 of the injection valve 312. The injection valve 312 comprises six ports (314, 315, 316, 317, 318, 319), with two ports (316, 319) configured as sample loop ports, two ports (314, 315) as high-pressure ports for supplying and discharging high-pressure fluid, and two ports (317, 318) as sample loading ports for supplying and discharging sample composition and / or fluid into and out of the sample loop. Ports 316 and 319 are connected to the sample loop 320 and configured as sample loop ports.Ports 314 and 315 serve as high-pressure ports for supplying and discharging high-pressure fluid. Port 314 is connected to the outlet line of the third pump 322, and port 315 allows the sample to be transferred to the chromatography column via a second connecting piece, as shown in more detail in Figure 1. Ports 317 and 318 of the injection valve 312 are connected to ports 303 and 308 of the pump supply switching valve 300, so that a sample can be introduced into the sample loop 320 and fluid can be discharged from the sample loop via these ports 317 and 318.

[0242] In the position combination shown in Figure 17, the pump supply line switching valve 300 is in the first switching position, in which fluid is drawn into the inlet line of the third pump and pumped into port 314 of the injection valve 312. The injection valve 312 of the addition unit 310 is switched in a first switching position, with the two high-pressure ports (314, 315) connected to each other for supplying and discharging fluid under high pressure.

[0243] In the switching position of the injection valve 312, port 316 is connected to port 317 and port 318 to port 319, with ports 317 and 318 being connected to ports 303 and 308 of the pump supply switching valve 300. In this switching position of the pump supply switching valve 300, ports 301 and 308 are connected, with port 301 serving to release the pressure of the fluid in the sample loop 320, as further details are described in Figure 3.

[0244] Furthermore, Figure 17 describes a further development of the embodiments shown in Figures 2, 3, and 4. In addition to the components described above, this embodiment includes a system 328 for flushing a sample feeder 324, wherein the sample feeder 324 can be connected to a sample container in a flow path. Preferably, the sample feeder can sequentially take samples from two or more sample containers, so that flushing of the sample feeder is advantageously carried out when the sample containers are changed. This is explained in more detail below. This can be done in the first switching position of the pump supply valve 300, wherein a fluid, preferably a third fluid, is pumped into the sample feeder 324 via ports 305 and 304.Furthermore, the embodiment shown in Figure 17 includes a system 330 for flushing the sample loop 320 and the connecting line between ports 303 and 317, as well as the connecting line between ports 308 and 318. In the switching position of the pump supply valve 300 and the injection valve 312 of the addition unit 310 shown in Figure 17, both the sample feed 324 and the sample loop 320, the connecting line between ports 303 and 317, and the connecting line between ports 308 and 318 can be flushed. Here, the systems 328 and 330 can be combined in a single flushing unit, so that one pump is used for flushing, which is switched as needed.Furthermore, the system for rinsing can also be designed by the rinsing pump 86 shown in Figure 5 in combination with other components, so that, for example, the port 68 shown in Figure 5 can be connected via a switching valve to both port 305 and port 302 of the pump supply switching valve 300.

[0245] Figure 18 schematically describes a preferably usable pump supply switching valve 340 and an addition unit 350 with an injection valve 351 in a switching position in which the sample loop 352 can be loaded.

[0246] Figure 18 shows a pump supply line switching valve 340 with eight ports (341, 342, 343, 344, 345, 346, 347, 348), with ports (342, 345) marked with the symbol "X" being closed. Port 341 serves to release pressure from a pressurized fluid, in particular a third fluid, so that a preferred embodiment of a pump supply line switching valve is shown here. Port 344 is connected to a sample container 360, port 346 to a liquid reservoir 362 for a third fluid, and port 347 to an inlet line of a third pump 364.

[0247] The outlet line of the third pump 364 is connected to a high-pressure port 353 of the injection valve 351. The injection valve 351 comprises six ports (353, 354, 355, 356, 357, 358), with two ports (355, 358) configured as sample loop ports, two ports (353, 354) as high-pressure ports for supplying and discharging high-pressure fluid, and two ports (356, 357) as sample loading ports for supplying and discharging sample composition and / or fluid into and out of the sample loop. Ports 355 and 358 are connected to the sample loop 352 and configured as sample loop ports.Ports 353 and 354 serve as high-pressure ports for supplying and discharging high-pressure fluid. Port 353 is connected to the outlet line of the third pump 364, and port 354 allows the sample to be transferred to the chromatography column via a second connection, as shown in more detail in Figure 1. Ports 356 and 357 of the injection valve 351 are connected to ports 343 and 348 of the pump supply line switching valve, so that a sample can be introduced into the sample loop 352 and fluid can be discharged from the sample loop via these ports 356 and 357.

[0248] In one switching position of the pump supply line switching valve 340, the inlet line of the third pump 364 is connected to a sample loop port 357 of the addition unit 350, as is explained in more detail below. This switching position of the injection valve 351 is also referred to herein as the first switching position of the injection valve, and that of the pump supply line switching valve 340 as the second switching position of the pump supply line switching valve.

[0249] In this first switching position of the injection valve 351 of the addition unit 350, the ports (356, 357) for loading the sample loop 352 are connected to the two sample loop ports (355, 358), and in the second switching position of the pump supply line switching valve 340, port 344, to which the sample container 360 is connected, is connected to port 343, and port 347, to which the inlet line of the third pump 364 is connected, is connected to port 348, with ports 343 and 348 of the pump supply line switching valve 340 being connected to ports 356 and 357 respectively of the injection valve 50.

[0250] In this switching position, a sample can be introduced into the sample loop 352. In this switching position, port 344 is connected to port 343 of the pump supply switching valve 340. Furthermore, in the injection valve, port 355 is connected to port 356 and port 357 to port 358. Accordingly, the third pump 364 draws a sample from sample container 360 into the sample loop 352 via ports 344, 343, 356, and 355, whereby a fluid previously located in the sample loop 352, for example, a third fluid or solvent, is conveyed into the inlet line of the third pump 364 via ports 358, 357, 348, and 347.

[0251] If a fluid, preferably a solvent, is provided for rinsing via the sample container 360, the sample loop 352 and the connecting line between ports 343 and 356 as well as the connecting line between ports 348 and 357 are rinsed.

[0252] In the embodiment shown in Figure 18, a flushing of the sample loop 352 and the connecting line between ports 343 and 356, as well as the connecting line between ports 348 and 357, is possible in a preferred embodiment. To improve this flushing, this embodiment includes a flushing control valve 370. In a flushing position, the flushing control valve 370 directs a fluid into a waste container 372 and, during chromatography, into a chromatography column 374, as shown in more detail in Figure 1. Preferably, a fluid, particularly preferably a solvent, is introduced into the sample feed via port 344 into the pump supply control valve 340.

[0253] This configuration is particularly advantageous when changing a solvent or fluid stored in liquid reservoir 362. This configuration can, of course, also be implemented in the embodiments described in Figures 2, 8, 11, and 13. Furthermore, the purge valve 370 can also be configured as part of a chromatography column selection unit, as described, among other places, in publication WO 2013 / 134222A1 as a column manager (SFC column manager), specifically on page 5, lines 10 to 15, where one column unit can be configured as an empty column.

[0254] The previously described position combination of valves 340 and 351 was similarly described in Figures 2, 8, 11 and 13, so that the explanations given at these points also apply accordingly to the embodiment described in Figure 18.

[0255] The features of the invention disclosed in the preceding description, as well as in the claims, figures and embodiments, can be essential for the realization of the invention in its various embodiments, both individually and in any combination.

Claims

Patent claims 1. Chromatography system comprising a first pump, which is connectable to or connected with a liquid reservoir for a first fluid, and a second pump, which is connectable to or connected with a liquid reservoir for a second fluid, wherein the pump outlet lines of the first pump and the second pump are connected by a connecting piece, and a chromatography column is provided downstream of this connecting piece in the direction of flow, and an injection unit is provided upstream of the chromatography column in the direction of flow, characterized in that the injection unit comprises a sample loop and an injection valve, wherein the injection valve has at least two sample loop ports and two high-pressure ports for supplying and discharging fluid under high pressure, as well as two sample loading ports for loading the sample loop.wherein the sample loop is connectable to or connected with the two sample loop ports of the injection valve, and a third pump is provided, the outlet line of which is connected to a high-pressure port of the injection valve and the inlet line of the third pump is switchable via a pump supply line switching valve, wherein in a first switching position of the pump supply line switching valve the inlet line of the third pump is connectable to or connected with a liquid reservoir for a third fluid and in a second switching position of the pump supply line switching valve the inlet line of the third pump is connectable to or connected with a sample loading port of the addition unit.

2. Chromatography system according to claim 1, characterized in that the third pump is a stepper motor pump.

3. Chromatography system according to claim 1 or 2, characterized in that the addition unit is provided downstream of the connecting piece, viewed in the direction of flow.

4. Chromatography system according to at least one of the preceding claims, characterized in that the pump supply switching valve and the injection valve can be switched in a coordinated manner.

5. Chromatography system according to at least one of the preceding claims, characterized in that in a first switching position of the pump supply line switching valve the inlet line of the third pump is connected to a liquid reservoir for a third fluid and the injection valve of the addition unit is switched in a first switching position, wherein the two high-pressure ports for supplying and discharging fluid under high pressure are connected to each other and the sample loading ports for loading the sample loop are connected to the two sample loop ports.

6. Chromatography system according to at least one of the preceding claims, characterized in that in a second switching position of the pump supply line switching valve the inlet line of the third pump is connected to a sample loading port of the addition unit and the injection valve of the addition unit is switched in a first switching position, wherein the sample loading ports for loading the sample loop are connected to the two sample loop ports.

7. Chromatography system according to at least one of the preceding claims, characterized in that in a first switching position of the pump supply line switching valve the inlet line of the third pump is connected to a liquid reservoir for a third fluid and the injection valve of the addition unit is switched in a second switching position, wherein the two high-pressure ports for supplying and discharging fluid under high pressure are connected to the two sample loop ports.

8. Chromatography system according to at least one of the preceding claims, characterized in that a mixer is provided between the connecting piece and the addition unit.

9. Chromatography system according to at least one of the preceding claims, characterized in that the chromatography system is controllable via a chromatography system control system.

10. Chromatography system according to at least one of the preceding claims, characterized in that a second connecting piece is provided which, viewed in the direction of flow, is located after the first connecting piece and before the chromatography column, wherein the second connecting piece is connected to the first connecting piece and the chromatography column via a high-pressure port for supplying and removing high-pressure fluid from the injection valve.

11. Chromatography system according to claim 10, characterized in that a check valve is provided between the high-pressure port for supplying and discharging high-pressure fluid of the injection valve and the second connecting piece.

12. Chromatography system according to at least one of the preceding claims, characterized in that the pump supply line switching valve has at least four ports, wherein one port is connected to the inlet line of the third pump, one port is connected to a sample loading port for loading the sample loop of the injection valve, one port is connected to a liquid reservoir for a third fluid and one port serves for pressure relief.

13. Chromatography system according to claim 12, characterized in that in a first switching position of the pump supply line switching valve the inlet line of the third pump is connected to a liquid reservoir for a third fluid and a port which is connected to a sample loading port for loading the sample loop of the injection valve is connected to the port which serves for depressurization.

14. Chromatography system according to at least one of the preceding claims, characterized in that the pump supply line switching valve has at least 6 ports, wherein one port is connected to the inlet line of the third pump, two ports are connected to two sample loading ports for loading the sample loop of the injection valve, one port is connected to a liquid reservoir for a third fluid, one port is connected to a sample container and / or a sample feeder, and one port serves for pressure relief.

15. Chromatography system according to claim 14, characterized in that in a first switching position of the pump supply line switching valve the inlet line of the third pump is connected to a liquid reservoir for a third fluid and a port which is connected to a sample loading port for loading the sample loop of the injection valve is connected to the port which serves for depressurization.

16. Chromatography system according to claim 14 or 15, characterized in that in a second switching position of the pump supply line switching valve, the inlet line of the third pump is connected to a sample loading port of the addition unit and the port connected to a sample container is connected to a port connected to a The sample loading port is connected for loading the sample loop of the injection valve.

17. Chromatography system according to at least one of the preceding claims, characterized in that the injection valve comprises eight ports, wherein two ports are sample loop ports, two ports are high-pressure ports for supplying and discharging high-pressure fluid, two sample loading ports are for loading the sample loop and two sealed ports.

18. Chromatography system according to claim 17, characterized in that in a first switching position of the injection valve the two high-pressure ports for supplying and discharging fluid under high pressure are connected to each other and the two sample loading ports for loading the sample loop are connected to the two sample loop ports and the two sealed ports are connected to each other.

19. Chromatography system according to claim 17 or 18, characterized in that in a second switching position of the injection valve two high-pressure ports for supplying and discharging fluid under high pressure are connected to the two sample loop ports and the two sample loading ports for loading the sample loop are connected to the two closed ports.

20. Chromatography system comprising a first pump which is connectable to or connected with a liquid reservoir for a first fluid, and a second pump which is connectable to or connected with a liquid reservoir for a second fluid, wherein the pump outlet lines of the first pump and the second pump are connected by a connector and, viewed downstream of this connector in the direction of flow, a A chromatography column is provided and, viewed in the direction of flow, an addition unit is provided upstream of the chromatography column, the chromatography system comprising a fraction collection device provided downstream of the chromatography column in the direction of flow, characterized in that the fraction collection device comprises a first fraction switching valve and a second fraction switching valve, the first fraction switching valve having at least four ports, one port of the first fraction switching valve being connected to the outlet line of the chromatography column, one port of the first fraction switching valve being connected to the outlet line of a rinsing pump, one port of the first fraction switching valve being connected to a port of the second fraction switching valve, and one port of the first fraction switching valve being connected to a fraction collector or a waste collection vessel.

21. Chromatography system according to claim 20, characterized in that in a first switching position of the first fraction switching valve the outlet line of the chromatography column is connected to a fraction collector or a waste collection vessel and the outlet line of a rinsing pump is connected to a port of the second fraction switching valve.

22. Chromatography system according to claim 20 or 21, characterized in that in a second switching position of the first fraction switching valve the outlet line of the chromatography column is connected to a port of the second fraction switching valve.

23. Chromatography system according to at least one of the preceding claims 20 to 22, characterized in that the first fraction switching valve has at least five ports, wherein the fifth port is equipped with is connected to a port of the pump supply switching valve set out in claim 1.

24. Chromatography system according to claim 23, characterized in that in a second switching position of the first fraction switching valve the outlet line of the chromatography column is connected to a port of the second fraction switching valve and the outlet line of a rinsing pump is connected to a port of the pump supply line switching valve.

25. Chromatography system according to at least one of the preceding claims, characterized in that the chromatography system is designed as an SFC system, wherein the chromatography system comprises a chromatography column and, viewed in the direction of flow, at least one back pressure regulator.

26. Method for carrying out chromatography comprising the use of a chromatography system according to at least one of the preceding claims 1 to 25.

27. Method according to claim 26, characterized in that the liquid reservoir for a first fluid contains a first solvent which is liquid under normal conditions, and the liquid reservoir for a second fluid contains a gaseous solvent which is gaseous under normal conditions.

28. Method according to claim 26 or 27, characterized in that, during loading of the sample loop, the pump supply line switching valve is switched to the second switching position and the injection valve of the addition unit is switched to a second switching position, wherein the sample loading ports for loading the sample loop are connected to the two sample loop ports are connected so that the third pump draws the sample to be separated from a sample reservoir into the sample loop.

29. Method according to at least one of claims 26 to 28, characterized in that when a sample to be separated is applied to the chromatography column, the pump supply line switching valve is switched to the first switching position and the injection valve of the addition unit is switched to a second switching position, wherein the sample loading ports for loading the sample loop are connected to the two high-pressure ports for supplying and discharging fluid under high pressure, so that the third pump pumps the sample to be separated from the sample loop to the chromatography column with a third solvent.

30. A method according to at least one of claims 26 to 29, characterized in that gradient chromatography is performed, wherein the proportion of first fluid at the beginning of the chromatography is in the range of 0 to 10 vol.% and this proportion of first fluid is increased, wherein the pump supply switching valve is switched to the first switching position and the injection valve of the addition unit is switched to a first switching position, wherein the two high-pressure ports for supplying and discharging fluid under high pressure are connected to each other, so that the third pump provides at least 50 vol.% of the first fluid at the beginning of the chromatography for the formation of the desired fluid mixture comprising a first and a second fluid.

31. Method according to at least one of claims 26 to 30, characterized in that when collecting valuable fractions of a sample, the first fraction switching valve is switched to the second switching position and The outlet line of the chromatography column is connected to a port of the second fraction switching valve.

32. Method according to at least one of claims 26 to 31, characterized in that when collecting valuable fractions of a sample, the first fraction switching valve is switched to the first switching position and the outlet line of a rinsing pump is connected to a port of the second fraction switching valve, wherein the outlet line of the chromatography column is connected to a fraction collector.

33. Conversion kit for converting a high-performance liquid chromatography system to a chromatography system according to at least one of the preceding claims 1 to 25, characterized in that the kit comprises at least one gas liquid separator and at least one pump supply line switching valve.

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