The present invention relates to a universal rotor for all systems requiring fluids to be subjected to centrifugal accelerations, this rotor being intended to perform any operations requiring the circulation of single-phase or multiphase fluids, for chemical and biochemical reactions, extractions, purifications or separations.
Apparatuses consisting of reactors for performing chemical and biochemical reactions, apparatuses for carrying out extraction operations, apparatuses for carrying out purification operations, apparatuses for performing separation operations such as those performed by centrifugal partition chromatography (CPC) are well known for many years.
A first drawback of the prior art relating to operations performed by centrifugal partition chromatography (CPC), extraction operations, purification operations and separation operations is due to the actual design of the cells and linking channels connecting them in series, hollowed out in the thickness of the discs which imposes the installation of seals, generally flexible, for example Teflon®, between each disc thus closing each cell and each channel along the plane of the disc, thus perpendicular to the main axis of each cell. Even if the cell has rounded shapes to facilitate homogeneity of the dispersion for better exchange of materials between the two phases, the planes of the seals make right angles, or even acute angles with the cell, due to the elasticity of the seal that partially inserts into the cells, which is poorly conducive to a homogeneous dispersion of the liquids, and therefore is a major drawback. Finally, these flexible seal planes have, firstly, a certain porosity which leads to an adsorption of certain molecules and to a subsequent desorption, which can limit the purity of the molecules of interest. Secondly, they are subjected to continuous variations in pressure of the liquids, getting deformed over time and modifying the geometry of the cells, leading to aging of the seals, even if measures are attempted to limit this ageing.
A second disadvantage of the prior art relating to centrifugal partition chromatography (CPC) and extraction operations, purification operations and separation operations is due to the fact that the cells are interconnected by a ribbon-shaped channel. It can be readily calculated and verified that this shape of duct, for a given section, leads to a loss of pressure head which is much higher than that caused by a duct of the same cylindrical cross-section or of a very close geometry thereto. To limit too large pressures and in some cases for reasons of difficulty in machining, it becomes necessary to increase the thickness of these rectangular channels, thus increasing the excessive volumes of said channels. The latter do not participate in the separation process in which the products being separated pass but they do increase transit times by an equivalent amount, and consequently separation time and consumption of solvents.
A third drawback of the prior art relating to centrifugal partition chromatography (CPC) and relating to extraction operations, purification operations and separation operations, is due to the fact that the mass and therefore the heat capacity of the rotor discs is not favorable to precise thermal regulation and more particularly to a thermal time constant which is as short as possible, particularly during reactor operation. The temperature of the fluids passing through the cells during reactions, which may be endothermic or exothermic, can become largely detrimental to the performance or even raise safety concerns if it is not strictly controlled. A fourth drawback of the prior art relating to centrifugal partition chromatography (CPC) and relating to extraction operations, purification operations and separation operations, is due to the fact that with the rotors of the prior art, if the injected volume is increased beyond a certain value with respect to the volume of the cells, a hydraulic shock phenomenon, commonly referred to as “water hammer” can arise which partially or totally destroys the hydrodynamic balance of the first cells, propagating to the last cells of the rotor and putting an end to the manipulation.
According to the techniques used heretofore, the rotors used in centrifugal partition chromatography (CPC) apparatuses for the separation of components, comprise, in their thickness and over their entire periphery, a succession of cells arranged in series in a radial or oblique direction through a set of fine meandering ducts connected to the inlet and the outlet of each cell, the circuits of all the discs communicating with each other. Rotation of the stack creates a large centrifugal acceleration field which makes it possible for example to maintain a liquid phase, referred to as the fixed stationary phase, while a mobile phase percolates through the stationary phase in a so-called ascending mode if it is lighter than the stationary phase, or in a so-called descending mode if it is heavier. In this type of apparatus constituted by the serial interconnection of one or more strings of cells, separation is performed of the constituents of a charge in liquid solution comprising at least two components having different partition coefficients in that they are driven at unequal speeds by the mobile phase which may be either of the liquid phases.
The rotors used in these known centrifugal partition chromatography (CPC) apparatuses can be used in all applications requiring a centrifugal acceleration field and very good thermal regulation, among other things to perform purifications, separations and extractions with conventional solvents but particularly with CO2 in liquid or supercritical phase in centrifugal partition chromatography (CPC), these being techniques in which molecules are purified and/or separated between two liquid phases, taking place in each cell, with mass transfer being promoted by good dispersion of the mobile phase arriving through the inlet channel of each cell. When it is desired to construct an industrial production apparatus, a person skilled in the art knows how to scale up from separations performed on a laboratory apparatus, i.e. the number of cells, the volume of said cells, the flow rates of the mobile phase, the hydrostatic pressure generated, etc. Nevertheless, as these parameters are relatively numerous and of necessity are subject to errors, the apparatus will operate, but will not be exactly at its optimum or modifiable simply with the technologies of the prior art.
The prior art apparatuses consist of rotors whose number and volume of the cells are defined before their construction and are not modifiable thereafter, which rules out possibilities of optimization for the various applications which may be present. To simplify things, we shall stick to the field of CPC separation, namely: if a user has a rotor of the prior art made up of 500 cells and it is desired to perform a given separation for which the optimum is 500 cells, everything will run smoothly. However, for another separation where 1000 cells would be required, said separation will only be partially resolved. Conversely, in the case of another separation to be performed with this same rotor having 500 cells, while a rotor having 200 would be the optimum, the duration of the separation will be multiplied by around 2.5 which results in a loss of time, increased solvent consumption and a reduction in productivity in the same ratio.
The present invention intrinsically provides, as regards the rotors used for separation, more particularly in centrifugal partition chromatography (CPC), significant advantages over known centrifugal partition chromatography (CPC) apparatuses, not only thanks to their duality of use, but also to their ease of use and ease of adaptation to particular operating conditions. The present invention provides a universal rotor making it possible:
The rotors according to the invention can also be applied to the two implementations mentioned above successively, namely a reaction between two or more compounds, followed by a separation of the desired product in the reaction mixture resulting from the chemical reaction or a separation of a component contained in a mixture followed by a chemical reaction of the component obtained with another product. The present invention can therefore be considered for each of these two applications and for successive use of the two applications.
The present invention provides a universal rotor for operations requiring fluids to be subjected to centrifugal accelerations in the context of operations requiring the circulation of single-phase or multiphase fluids, for chemical and biochemical reactions operating in particular continuously, purifications, extractions, separations, centrifugal partition chromatography (CPC), liquid-liquid extractions among others. The rotor according to the invention is capable of being implemented as chemical and/or biochemical reactors, liquid-liquid extractors, in purification operations, centrifugal partition chromatographs (CPC), among others. The liquid or solvent phases may comprise, among other things, organic solvents, ionic solvents, NADES (natural deep eutectic solvents), CO2 in liquid or supercritical phase circulating in cells connected to each other by channels, and being applied, in different fields, such as those of chemical and biochemical reactions, of extraction, of purification, of separation.
The present invention provides a universal rotor for operations requiring fluids to be subjected to centrifugal accelerations involving the circulation of single-phase or multiphase fluids, for treatments consisting of purifications, extractions, separations, centrifugal partition chromatography (CPC), liquid-liquid extractions, chemical and biochemical reactions, wherein:
According to one embodiment of the invention, the rotor is formed by a single circular sector comprising a network of successive cells interconnected by channels both arranged in a plane approximately at a midpoint of its thickness, characterized in that there is at least one gap between its two ends for arranging a linking connector in a sealed manner, said linking connector comprising at least one inlet and at least one outlet intended to respectively allow entry of a liquid mixture into said network of cells and the exit of said mixture from the network of cells. According to another embodiment of the invention, the circular sectors are made from two circular half-sectors, each of which is the mirror image of the other, both comprising on their mirror plane, half-cells and half-channels, the two half-sectors being assembled in a sealed manner, preferably by diffusion welding, face-to-face, to become a circular sector.
According to yet another embodiment of the invention, the circular sectors are preferably made in one piece, for example directly by additive construction. According to yet another embodiment of the invention, the single circular sector comprises, in its thickness, one or more ducts having a generally rectangular cross-section each arranged in a circular pattern, typically three, delimited by concentric walls and arranged such that an average radius of each of said ducts arranged in a circular pattern substantially corresponds to a respective same mean radius of a corresponding network of cells arranged in a circular pattern, for circulating a temperature control or thermostatting fluid in said ducts in a fashion that is as identical as possible for each network of cells.
According to one embodiment of the invention, the linking connector comprises the necessary branches so that the temperature control fluid or thermostatting fluid entering passes through all the ducts connected in series of each one of the circular sectors constituting a said ring, and then guided by said linking connector, passes to the linking connector of a next disc in order to pass in the same way through the ducts connected in series, and continuing in this way up to the outlet of the rotor. According to yet another embodiment of the invention, said linking connector also includes an inlet and an outlet allowing entry and exit of a temperature control or thermostatting fluid in order for it to pass through the at least one temperature control or thermostatting fluid duct.
According to one embodiment of the invention, the cells and channels have walls as thin as possible, and are provided with fins, said fins being themselves integral with the internal walls of the circular sector. According to another embodiment of the invention, the linking connector comprises at least one inlet and at least one outlet for respectively allowing entry of a liquid mixture into the networks of cells and the exit of said mixture from the networks of cells, such that between the outlet and the inlet, the liquid phase passes through all the cells and channels of a respective disc.
According to yet another embodiment of the invention, linking connector (B6) can be installed in place of linking connector (A6), in which case a single or multi-way ball valve comprising “ON” and “BYPASS” positions is added thereto, making it possible to select positions such that in the “ON” position of said valve a liquid phase entering at (31) is directed at (32) of said valve to then enter the inlet (13) of a contiguous circular sector in order to traverse the entire network of cells of a disc and arrive at (14) of the last circular sector and then to (35) and then to (36) of the linking connector, to enter the next contiguous disc at (31) of the linking connector thereof but, if the ball of said valve (42) is in the “BYPASS” position, the liquid phase entering at (31) is directed directly to (36) without traversing the cells of the disc concerned, the latter being short-circuited, allowing the user to adjust the number of cells to each of its various applications in steps by the number of cells contained in a disc.
According to yet another embodiment of the invention, each circular sector of a ring is formed of two superimposed circular half-sectors, face-to-face, or of a stack of such superpositions, each of these half-sectors comprising half-cells whose angles (20) are replaced by chamfers forming rounded surfaces. According to another embodiment of the invention, in order to increase the productivity of said rotor, in the CPC mode, in the ascending mode, the “n” first cells of said rotor have decreasing volumes according to a determinable function ranging from (V7) to (V) with (V7>V), V being the constant volume of the majority of the cells of said rotor.
The present invention also relates to the use of the universal rotor in operations requiring fluids to be subjected to centrifugal accelerations in the context of operations requiring the circulation of single-phase or multiphase fluids, for purifications, extractions, separations, centrifugal partition chromatography (CPC), liquid-liquid extractions. The present invention also relates to the use of the universal rotor in operations requiring fluids to be subjected to centrifugal accelerations in the context of operations requiring the circulation of single-phase or multiphase fluids, for chemical and/or biochemical reactions. The invention will be better understood on reading the following description of preferred embodiments, given as a simple, non-limiting example, and accompanied by the following drawings.
The ring A1 shown in
In the case of several circular sectors 2 to 5, the two ends of the circular sectors 2 and 5 correspond to one end of a first circular sector 2 which is not connected to another circular sector, and to one end of a last circular sector 5 also not connected to another circular sector. In the case of a single circular sector, its two ends correspond to those of an assembly of several circular sectors.
A linking connector 6 is interposed in a sealed manner between the two ends of the assembly of the circular sectors 2 to 5. This linking connector makes it possible, in one embodiment of the invention, to allow the mobile phase and the sample to be injected to enter into the ring A1, and then after they have passed through all the cells, to direct them into a linking connector of an adjacent ring which in turn performs the same function, and so on up to the last ring of a rotor constituted by a stack of discs. The various components of the sample entrained by the mobile phase, in the case of a CPC separation application for example, are separated during the course of their path through the cells and channels, and then are detected and/or collected by one of the well-known means used in liquid/liquid centrifugal partition chromatography CPC or for applications performed in other fields. The linking connector may have other functions according to the invention which will be presented in the detailed description of
Their respective channels 18 and 19 linking the cells, see the section taken along line B-B of
According to the invention, rounded surfaces or chamfers 20 are made, shown in detail in the enlarged view of half-cell 27A, instead of cells having sharp corners, these latter considerably degrading hydrodynamic operation and consequently performance of the apparatus. This manner can be advantageously applied to all conceivable geometries of cells, whether they are symmetrical or dissymmetrical and whatever their various applications. The channels 18 and 19 linking the cells are advantageously circular in cross-cross-section, also for good hydrodynamic operation. However, in the case of conventional mechanical machining of said channels, it will be possible for reasons of ease of machining and/or state of their surface, to give them a polygonal cross-section, for example square, taking care to round all the angles in order to obtain a cross-section closest to a circular cross-section.
To aid understanding, the linking connectors A6 and B6,
Said linking connector A6 or B6
In the Bypass position, the mobile phase which had previously filled the cell network concerned is trapped therein. The mobile phase entering at ports 29 or 31 of the said linking connector is directed directly by the ball valve towards the outlet 34 or 36 of the linking connector adjacent to the next linking connector of the stack. This embodiment makes it possible for the user, by turning the ball valve 41 one quarter of a turn in one direction or the other by means of a screwdriver introduced into slot 43, to adjust the number of active cells of the rotor in steps corresponding to the number of cells contained in a disc. The operation of this major embodiment of the invention is shown more in detail in the following discussion of
The linking connectors 6, whether they are of fixed configuration A6 of
Cross-section E1-E1 is an assembly view including the double-channel ball valves adapted to the two networks of cells of different volumes V and 8V of the present embodiment. For its use, the network corresponding to the volume of the selected cells is selected by connecting, for example, the arrival of the mobile phase in descending mode to the inlet 56, outlet 57 then being that of the rotor which will be connected to a detector and to a fraction collector, for example. It is recommended to connect a plug at ports 54 and 55, to prevent the phase in the corresponding cell network from escaping, so as not to risk a dynamic imbalance of the rotor when rotating. Cross-section E1-E1 also shows the inlet and outlet 58 and 59 intended for the circulation of a liquid for controlling temperature or a thermostatting fluid for the rotor.
Cross-section E2-E2 more precisely shows the hydraulic operation of the valves “RUN”-“BYPASS” showing, on a larger scale in
The cross-section E3-E3 shows the plane parallel to cross-section E2-E2 and passing through the axis of the connectors 58-59. The temperature control liquid or thermostatting fluid enters, for example by the connector 58, then arrives at the inlet 37 of the first linking connector A6 or B6. A diverter 60 directs it in the direction of the arrows towards the temperature control liquid or thermostatting control channel 12A of the contiguous circular sector. After the temperature control liquid or thermostatting fluid has passed through all the ducts 12A, 12B to 12C of the circular sectors of the disc, it arrives at duct 12C to be directed at port 38 of diverter 60 of the linking connector and directly passes from outlet 38 to the inlet 37 of the adjacent linking connector of the next disc until it arrives at the outlet 59 of the rotor.
In this example, the mobile phase thus passes through 320 cells of the rotor that comprises 480. It is possible to produce rotors with many more cells to widen the field of applications. It can be seen, for example, that the number of cells used in such a rotor can be modified by a number of cells corresponding to the number of cells contained in each disc, by performing a quarter turn of the balls 41 of valves 42 and thus making it possible to operate with 80, 160, 240, 320 or 400 cells of such a rotor, depending on the requirements of the separations to be performed. If the light mobile phase is connected to inlet 57, the path in the networks of cells remains the same but in ascending mode.
These rotary seals must be adapted to the pressures and speeds of rotation involved and must be of easy access in order to simplify maintenance, cleaning, changes in seals, after-sales servicing, etc. A nut 86 having a bore for receiving a spring 87 is threaded onto rotor shaft 85 so that the spring 87 provides sufficient permanent pressure to ensure sealing of all the seals of the discs of the stack constituting the rotor and so that the assembly is mechanically homogeneous and stable. The frame carrying this mechanical assembly is fixed to the apparatus by dampers 92 provided for this purpose, to which safety fasteners are added along with mechanical locking means for transport, complying with applicable standards.
For the calculation and construction of a production apparatus intended to carry out a given application long term, calculations and experiments for scale change, derived from results of measurements performed on laboratory devices, preferably equipped with “RUN-BYPASS” valves on each disc according to the invention, should save on time and precision. However, measurements may be somewhat affected by error, an industrial rotor constructed on these bases may not be exactly at its optimum, a defect that can be easily corrected by the technological flexibility of the invention, because it is possible to add or remove one or more discs making it possible to optimize performance under actual conditions and by adjusting the number of cells necessary, this operation being simplified by the construction of the discs using assembly of circular sectors, said circular sectors being able to have more or fewer cells on demand.
View A of
This embodiment presented with a vertical axis does not exclude an assembly made with a horizontal or articulated axis of rotation allowing the portion supporting the rotor to be angularly displaced. A person skilled in the art will know the use of various means known in conventional mechanics in order to put such a mounting into practice.
It is useful to employ discs equipped with a valve 42 according to the invention making it possible to connect or not, all or parts of the discs of the rotor comprising the networks of cells of different volumes in order to adjust the number as a function of the needs of each application. The rotor according to the invention is used in centrifugal partition chromatography CPC operations allowing the separation of a compound contained in a solution formed from several components. The separation of the sample is based on the partition coefficients specific to each of the components of the sample between the mobile and stationary phases. The partition coefficient determines the affinity of each molecule in the mobile and stationary phases and therefore the speed at which each molecule moves in the system. At the end of the purification process, automated fraction collectors retain all the selected fractions according to the parameters of the program.
The rotor according to the invention can be used not only in separation operations, but also for reaction operations between components, thus acting as an intensified chemical and/or biochemical reactor due to the excellent mixing occurring in each of the cells. The advantage of the system is that of obtaining a plug flow reactor-like behavior, which is recognized to give the best performance, considering said universal rotor as a succession of perfectly stirred reactors, consisting of the cells. The reactions can be carried out in single phase or be diphasic, which is most relevant when the reactants and the product are in different phases.
This invention makes a clean break with conventional batch processes: the double jacketed stirred tank, which is the most frequently used tool, with more than 50% of chemical production units in the world. The engineering of the reactors comprises two key elements: the kinetics of the reactions and the design of the reactors. The design of the reactors must be thought through so that the reaction proceeds at its intrinsic speed, that is to say if there is a perfect mixing and mass transfer in the reactor.
Often, in large, stirred tank reactors, the reaction does not take place at its intrinsic speed because it is limited by the mixing in the tank, that is, the reactants are not perfectly mixed. In this case, it is known that it is “limited by the mixing”. The role of an intensification of the process is to reduce or eliminate these limitations so that the reaction can reach its intrinsic rhythm. Thus, the purpose is to ensure that the mixing and heat/mass transfer rates will be relatively fast with respect to the fundamental kinetics of the process. A high acceleration can be obtained as long as is required by operating in such a rotary system. Transposing chemical syntheses in reactors in which the phases have a piston-like flow, then makes it possible to minimize reaction volumes (safety of installations and operators), to intensify the exchanges of material (mixing, reaction, separation), to regulate and control the temperature with good precision and to add alerting systems in the event of overshoot. Examples include the reduction of benzal-aldehyde to benzyl alcohol by homogeneous ruthenium catalysis, or the two-phase esterification reaction of oleic acid to ethyl oleate by a lipase (Candida Antarca).
Liquid/liquid extraction is a basic operation in the field of process engineering. It consists in passing a solute (the molecule of interest) from a so-called “feed” phase to a so-called “extract” phase. The two phases are immiscible or partially miscible. Many examples exist in the industry, for example the production of antibiotics with an acido-basic extraction cycle.
Number | Date | Country | Kind |
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FR2006514 | Jun 2020 | FR | national |
The present application is a national phase entry of PCT application no. PCT/EP2021/063872 filed on May 25, 2021, which claims priority to French application no. 2006514 filed on Jun. 22, 2020, both of which are incorporated by reference herein.
Filing Document | Filing Date | Country | Kind |
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PCT/EP2021/063872 | 5/25/2021 | WO |