Abstract: A process is disclosed for separating biomolecules from an aqueous solution containing the biomolectules and impurities, having different affinities and/or interactions with a solid support. The solution is passed over a fixed bed of chromatographic resin containing at least three zones, with flow of liquid being arranged between adjacent zones and between a last and first zone. Each of several sequences includes at least an adsorption stage, a rinsing stage, or a desorption stage, with each subsequent sequence being carried out by a downstream displacement of fronts in the zones by approximately the same increment before the periodical displacement of the introduction and withdrawal points.

Abstract: A process for continuous or quasi-continuous purification of a multi-component mixture by means of at least four individual chromatographic columns through which the mixture is fed by means of at least one solvent, is given, wherein the multi-component mixture is to be separated into an integer number n of fractions, wherein n is at least 5.

Abstract: In accordance with an embodiment of the invention, there is provided a method for reducing or eliminating matrix interfering components in a biopharmaceutical product in a liquid chromatography-mass spectrometry system. The method comprises diverting to waste the entire flow of an eluant emerging from liquid chromatography of a sample, for a time period to remove contaminants that cause matrix interference to a degree sufficient to allow a desired accuracy in detection of an extractable; and, after the time period, directing the entire flow of the eluant to a mass spectrometer to detect the presence of the extractable.

Abstract: A flow controller for use with a liquid chromatography detector. The flow controller includes a flow channel comprising an inlet portion, a control channel portion in communication with the inlet portion, and an outlet portion in communication with said control channel portion. The control channel portion has a cross-sectional area smaller than a cross-sectional area of a drift tube of the liquid chromatography detector for channeling the flow of droplets through the smaller cross-sectional area. The flow controller is shaped and sized to reduce pressure fluctuations and turbulence in the droplet stream of the liquid chromatography detector.

Abstract: A solid-phase extraction device utilizing a section of expanded polytetrafluoroethylene (ePTFE) tubing as the stationary phase is disclosed. The microscopic pores of ePTFE tubing are impregnated with a binding agent having an affinity for a target constituent within a matrix. The matrix is prepared and loaded onto the stationary phase of the system. The target constituent is retained by the stationary phase. The constituent is stripped from the stationary phase with a stripping solution, and collected for further analysis or use.

Abstract: Product yields in chemical reactions that produce a solid product from a liquid reaction mixture are improved by chromatographically separating certain key impurities from the product mixture prior to crystallization, or from the filtrate after crystallization in which case further product is crystallized from the filtrate. The removal of key impurities either before the first crystallization or between the first and second crystallizations facilitates the crystallization of product to produce a higher yield of product.

Abstract: The apparatus of the present invention relates to rotary valves which provide simultaneous interconnection of a plurality of asymmetrically disposed stationary adsorption chambers in fluid communication with an upper stator of the rotary valve having a lower rotor which upon indexing in accordance with a predetermined periodic sequence provides a simulating bed moving process. Further, the apparatus relates to such combinations of adsorbent chambers and rotary valves in a manner which is useful for implementing a simulating moving bed process wherein the continuous contacting of fluids and solids occurs in order to affect a separation or a purification process in a substantially plot area than previous SMB systems using turntable arrangements of adsorbent chambers.

Abstract: A method for the chromatographic separation of components of a multicomponent fluid mix by means of the simulated moving bed method wherein the multicomponent fluid mix and at least one solvent are fed to inflows of a plurality of chambers containing at least one solid substance and connected to each other in series to form a closed loop. An extract stream containing at least one first component separated from the multicomponent fluid mix as well as a raffinate stream containing at least one second component separated from the multicomponent fluid mix are carried out of the chambers through a first and second outflows. At least part of the raffinate stream and/or extract stream carried off at the first and/or second outflows is preliminarily stored and recirculated to the first and/or second inflow of the chambers alternately or simultaneously with the multicomponent fluid mix and/or the solvent within one clock unit.

Abstract: Disclosed herein is a simulated moving bed chromatography device comprises a minimum of one stationary pipe with a plurality of inlet/outlet channels, a rotary device next to the stationary pipes, a stationary radial flow segmented vessel communicates with the rotary device, a fluid moving device and a drive means to rotate the rotary device. The counter movement of the stationary phase and the fluid is simulated by rotating the rotary device in the same direction as the circulating fluid flow, and the fluid flows through the flow distribution segments, the stationary phase segments, the outer fluid transfer segments, holes or by passes of the improved partition plates in the flow distribution segments/compartments and outer fluid transfer segments.

Abstract: A chromatography or supercritical extraction method is disclosed, in which the eluent comprises a mixture of a fluid and a modifier and in which the fluid is recycled. One exemplary method comprises an operation consisting in determining at least one quantity linked to the level of modifier that is mixed with the recycled fluid and, if necessary, a correction operation in order to limit variations in the level of modifier in the eluent at the inlet of the column or the extractor. The disclosure also relates to a chromatography or extraction installation.

Abstract: The invention concerns a method for separating fractions of a mixture using a chromatography device. The method includes the following steps: controlling in one node of the device, the history of a specific variable of the fractions of the mixture to be separated; detecting one characteristic point of the history, the characteristic point being between two successive steps of fraction collecting; comparing the position of the characteristic point relative to a target position; adjusting the amount of mobile phase modifying the position of the characteristic point to cause the position of the characteristic point to coincide with the target position. The invention also concerns a device for implementing the method. The method enables the operation of the device to be automatically set.

Abstract: One exemplary embodiment can be a separation system. The separation system can include an adsorption zone, a rotary valve, a transition zone, and one or more pipes. Usually, the transition zone includes one or more lines communicating the rotary valve with the adsorption zone. The rotary valve alternatively may distribute an input of a feed or a desorbent to the adsorption zone or alternatively can receive an output of a raffinate or an extract from the adsorption zone in a line, and a remnant may remain in the line from a previous input or output. One or more pipes outside the transition zone communicating with the rotary valve can form at least one pipe volume receiving an input for dislodging a remnant or for receiving a remnant from the line. The remnant may be different from the input or output.

Abstract: The present invention relates to a chromatographic separation process for fractionating betaine-containing solutions by utilizing fractions comprising parts of the separation profile as a substituent of the eluent in a novel and inventive manner. The process provides improved separation capacity and separation efficiency without affecting the yield or purity of betaine or other products. The process can especially be applied to sequential SMB separation systems.

Abstract: A process is disclosed for separating biomolecules from an aqueous solution containing the biomolectules and impurities, having different affinities and/or interactions with a solid support. The solution is passed over a fixed bed of chromatographic resin containing at least three zones, with flow of liquid being arranged between adjacent zones and between a last and first zone. Each of several sequences includes at least an adsorption stage, a rinsing stage, or a desorption stage, with each subsequent sequence being carried out by a downstream displacement of fronts in the zones by approximately the same increment before the periodical displacement of the introduction and withdrawal points.

Abstract: The present invention provides methods of separating at butanediol compound from a mixture containing polyhydric alcohols and butanediol compounds. The mixture of polyhydric alcohols typically contains propylene glycol and ethylene glycol in addition to the butanediol contaminants. Butanediol contaminants are removed by contacting the mixture with a chromatographic matrix. Either the butanediol compounds or the non-butanediol compounds adsorb to the chromatographic matrix. If desired, the adsorbed compounds may be eluted from the matrix, purified and used in products.

Abstract: Provided is a method of manufacturing target substances with use of supercritical fluid chromatography, by which the following are achieved: solution of a problem at the time of sequential injections of samples containing the target substances; an increase of a treatment amount of separation per unit time; and improvement of efficiency in separation. The method includes the steps of: injecting the sample containing the target substances into a mobile phase; and returning composition of the mobile phase to a pre-change state after changing the composition of the mobile phase. The step of returning the composition of the mobile phase to the pre-change state after changing the composition of the mobile phase is performed during a period of time from detection of a peak of one of the target substances which is eluted latest from a column among the target substances separated by the supercritical fluid chromatography apparatus to injection of the next sample, whereby the problem is solved.

Abstract: A process for separating a feed F by simulated moving bed adsorption in a SMB device comprises external bypass lines Li/i+1 which directly connect two successive plates, Pi, Pi+1, the index “i” being either even or (exclusive of the foregoing) odd, along the whole length of the column, allowing said plates to be flushed, in which each of the bypass lines Li/i+1 comprises automated means for regulating the flow rate in the bypass lines, the bypass lines in certain cases being subject to a flushing flow during injection or withdrawal operations.

Abstract: A process for separating a feed F by simulated moving bed adsorption in a SMB device is described, the device comprising external bypass lines Li/i+1 which directly connect two successive plates Pi, Pi+1, the index i being either even or (exclusive of the foregoing) odd, along the whole length of the column, in order to flush said plates, in which each of the bypass lines Li/i+1 comprises automated means for regulating the flow rate in the bypass lines, the degree of opening of said regulating means being defined by the following three rules: a) establishing a flow rate corresponding to an oversynchronicity in the range 15% to 30% in all of the open bypass lines of zone 1; b) establishing a flow rate corresponding to the synchronicity to within plus or minus 8% in all of the open bypass lines of zones 2 and 3; c) establishing a flow rate corresponding to an oversynchronicity in the range 20% to 40% in all of the open bypass lines of zone 4.

Abstract: A process for separating a feed F by simulated moving bed adsorption in a SMB device comprises at least one zone 1 for desorption of the compounds produced in the extract, a zone 2 for desorption of the compounds produced in the raffinate, a zone 3 for adsorption of the compounds produced in the extract, a zone 4 located between the raffinate withdrawal and the desorbant supply, the device comprising external by-pass lines Li/i+1 directly connecting two successive plates Pi and Pi+1; in which the degree of opening of means for restricting the flushing flow rate of the by-pass lines Li/i+1 are sequentially modified such that: 1) in an operational zone where there is at least one closed by-pass line, a super-synchronicity of the flushing flow rate is established in all of the by-pass lines which are not closed belonging to the zone under consideration, said super-synchronicity being defined by the following formula: S=a+b(nf/nt) in which the constant a is a constant in the range ?5 to 5 and b is a constant

Abstract: A fraction collector comprising a movable tray is provided. The movable tray may be attached to the fraction collector support system in a variety of ways and adjusted without adjusting the parts of the fraction collector support system. The moveable tray may be stably attached to the fraction collector support system by either fixed or removable pegs, as well as by channels. In an exemplary embodiment, a mechanized lift is used to adjust the position of the movable tray.

Abstract: A chromatography or supercritical extraction method is disclosed, in which the eluent comprises a mixture of a fluid and a modifier and in which the fluid is recycled. One exemplary method comprises an operation consisting in determining at least one quantity linked to the level of modifier that is mixed with the recycled fluid and, if necessary, a correction operation in order to limit variations in the level of modifier in the eluent at the inlet of the column or the extractor. The disclosure also relates to a chromatography or extraction installation.

Abstract: The present invention provides a method for determining a level of a RuBP, PGA, 2-PA in a photosynthetic cellular extract by resolving at least one RuBP, PGA, or 2-PA or combinations thereof in a photosynthetic cellular extract obtained from a plant. In another aspect, it provides for detecting at least one resolved RuBP, PGA, or 2-PA or combinations, thereby determining a level of the resolved RuBP, PGA, or 2-PA or combinations. In one aspect the photosynthetic cellular extract is obtained from a plant subjected to an abiotic stress. A method of the invention can be useful, for example, for identifying plants with increased photosynthetic performance. Also included herein is a high throughput system for identifying a plant with increased photosynthetic performance.

Abstract: An ion chromatography apparatus comprising: (a) a first chromatography column, (b) a second chromatography column, the volume of the second column being no greater than 0.9 times the volume of the first; and (c) valving disposed between said first and second columns permitting selective transfer of separated ionic species from first chamber to second chamber for further analysis.

Abstract: Disclosed herein are an apparatus and a method for separating molecules on the basis of size and or structure, and to a method of making the apparatus. Generally, the separation method includes passing a fluid comprising particles having different effective molecular diameters through a plurality of open, nanoscale channels disposed in surfaces of substrates. The method also includes obtaining a plurality of fractions of the passed fluid such that each of the fractions includes a major portion containing particles having similar size and shape and substantially free of particles having larger size and shape. The apparatus includes first and second substrates each of which has a surface containing a plurality of open, nanoscale channels disposed therein. The surfaces are bonded together such that each of the channels of the first substrate is in fluid communication with at least two of the channels of the second substrate and is misaligned relative to the channels of the second substrate.

Abstract: A process for separating a feed F by simulated moving bed adsorption in a SMB device comprises external bypass lines Li/i+1 which directly connect two successive plates, Pi, Pi+1, the index “i” being either even or (exclusive of the foregoing) odd, along the whole length of the column, allowing said plates to be flushed, in which each of the bypass lines Li/i+1 comprises automated means for regulating the flow rate in the bypass lines, the bypass lines in certain cases being subject to a flushing flow during injection or withdrawal operations.

Abstract: Provided herein are methods of liquid column chromatography in which preparative chromatography is performed in-line with analytical chromatography. In particular aspects a monolithic preparative column is used to purify an analyte of interest from a mixture of other substances by applying the mixture to the column, reversing the flow through the column to elute the analyte, which is applied to an analytical column provided in-line with the preparative column. In other aspects, a single monolithic column is used to perform both the preparative chromatography and analytical chromatography steps in succession. In another aspect, a chromatography system is provided to perform preparative and analytical chromatography using a single monolithic column.

Abstract: Pretreatment method and apparatus to remove matrix ions from a liquid sample, prior to separation of the sample analytes (e.g. by chromatography), by flowing the liquid sample into a sample compartment and stopping the flow. The sample compartment has a wall comprising an ion exchange membrane having exchangeable ions of the same charge as the matrix ions to be removed. A regenerant liquid stream flows through a regenerant flow compartment on the other side of the membrane from said parked liquid sample. Matrix ions in the parked liquid sample are transported across the membrane into the regenerant flow compartment. Suppression may be performed electrolytically and/or chemically. A concentrator column may also be used.

Abstract: A process for continuous or quasi-continuous purification of a multi-component mixture (Fd) by means of at least four individual chromatographic columns through which the mixture is fed by means of at least one solvent (s), is given, wherein the multicomponent mixture (Fd) is to be separated into an integer number n of fractions (Fi), wherein n is at least 5. The columns are grouped into at least six sections ((?1, . . . , ?n-3, ?1, . . . , ?n-3, Y, ?), wherein each section ((?1, . . . , ?n-3, ?i, . . . , ?n-3, ?, ?) comprises at least one column with the proviso that the function of sections can be fulfilled sequentially and can be realized by single columns. There are least two collection, at least two recycling sections (?1, . . . , ?n-3), a strongly adsorbing component collection section (?) and a feed section (?) The functions of the sections ((?1, . . . , ?n-3, ?i, . . .

Abstract: A process for separating a product from a multicomponent feedstream to an adsorption apparatus or system is described. The apparatus or system may comprise a moving-bed or a simulated moving-bed adsorption means. The product comprises at least one organic compound, such as an aryl compound with alkyl substitutes. In embodiments the conduits used to supply the feedstream to the apparatus or system are flushed with media of multiple grades. The improvement is more efficient use of the desorbent. In embodiments the process achieves improvements in one or more of efficiency of adsorption separation, capacity of adsorption apparatus systems, and purity of product attainable by adsorption process.

Abstract: Disclosed is a method for producing a target substance by separating it from a mixture using a simulated moving bed chromatography (SMBC) separation system, which can minimize decreases in separation performance due to interference from a liquid accumulation portion. A material, in which the target substance in the material can be separated using a first SMBC separation system that meets a first condition, is processed to separate and produce the target substance from the material using a second SMBC separation system that meets a second condition, wherein the particle size of a separating agent and fill length of a column tube are both greater, the pressure loss by the column is substantially the same, and the volume ratio of liquid accumulation portions in the endless flow passage of the SMBC separation system is lower.

Abstract: This invention relates to a breakthrough in the art of chromatography allowing 1) larger scale of operation; 2) faster processing time; 3) disposability; 4) reduction of media/resin expenses; and 5) a reduction of capital equipment investment. In this invention, the chromatography column is replaced by a module that consists of two or more interconnected tangential flow filters and static mixers. The chromatography resin flows through this module in a single pass, while similar operations to a regular chromatographic process are performed on the resin (binding, washing, elution, regeneration, and equilibration). The buffers for these operations are pumped into the module in a countercurrent direction to the flow of resin, and permeate solutions from later stages are recycled back into previous stages. This creates concentration gradients in the permeate solutions of the tangential flow filters in the countercurrent direction to resin flow, thus saving buffer volume and increasing process efficiency.

Abstract: Disclosed herein is a suppressor using one ion-exchange tube which has an inner diameter close to that of a tube connected to a separation column and which is constituted by an ion-exchange membrane. The ion-exchange tube is folded or wound more than once in a plane into a sheet form to provide an ion-exchange tube sheet through which an eluate from a separation column flows. The ion-exchange tube sheet is accommodated in a container. The container provides a regenerant flow channel so that a regenerant is allowed to flow on both sides of the ion-exchange tube sheet.

Abstract: The invention concerns a method for separating fractions of a mixture to be separated, in a device (1) comprising: several chromatography columns (21, 22, 23,) mounted in series; an open separation loop comprising in input a point for injecting (6) eluent in one of the columns and in output a point for drawing (8) a fraction of the mixture. The method includes the following steps: batch injection of the mixture to be separated in the open separation loop (4); collecting at least two fractions; offsetting at least one column of the eluent injecting and fraction drawing points (6, 8) of the separation loop (4). The invention also concerns a device for separating fractions of a mixture to be separated.

Abstract: The present invention relates to a process of enriching element content in stable isotopes of light elements in ion-exchange chromatography. The process comprises development of band of light elements in a chromatographic column; elution of said band in a discontinuous basis so as to disconnect said chromatographic column at particular stage; and finally the process comprises of regeneration step.

Abstract: The present invention relates to a chromatographic separation process for fractionating solutions containing sugars, sugar alcohols, sugar acids and/or betaine by utilizing fractions comprising parts of the separation profile as a substituent of the eluent in a novel and inventive manner. The starting solutions are typically multicomponent plant-based extracts and hydrolysates, stillages, and fermentation products and derivatives thereof. The process prow vides improved separation capacity and separation efficiency without affecting the yield or purity of product components, such as sugars, sugar alcohols, sugar acids, and betaine. The process can especially be applied to sequential SMB separation systems.

Abstract: The invention relates to a miniaturized gas chromatograph and injector for the same. Said micro-GC is compact and simple and economical to construct. Dead volumes are largely avoided in order to achieve reliable and reproducible measured results. Said miniaturized gas chromatograph comprises at least one injector, one separation column and a detector which are combined on a circuit board to give a gas chromatography module. The injector comprises a first sheet with channels, which is provided with a second sheet with channels and which may be displaced relative to the latter, whereby at least one of the sheets is provided with a layer of plastic, in particular a chemically inert plastic on the side of the sheet facing the other side.

Abstract: The subject of the present disclosure is a multi-column sequenced separation process and a drive for implementing this process. The disclosure applies particularly to the separation of metal derivatives such as uranium, nickel, copper, cobalt and other precious metals present in leaching effluents in hydrometallurgical processes.

Abstract: Disclosed is a method for producing a target substance by separating it from a mixture using a simulated moving bed chromatography (SMBC) separation system, which can minimize decreases in separation performance due to interference from a liquid accumulation portion. A material, in which the target substance in the material can be separated using a first SMBC separation system that meets a first condition, is processed to separate and produce the target substance from the material using a second SMBC separation system that meets a second condition, wherein the particle size of a separating agent and fill length of a column tube are both greater, the pressure loss by the column is substantially the same, and the volume ratio of liquid accumulation portions in the endless flow passage of the SMBC separation system is lower.

Abstract: A device is provided for chromatographic separations comprising a manifold comprising a plurality of connectors for connecting to one or more chromatographic separation columns and/or feed or extraction tubing. At least one central duct is formed between at least two connectors forming an inlet and an outlet respectively. The central duct comprises a closable duct valve; and a plurality of branch ducts branching from the central duct to a branch connector. The branch duct comprises a closable branch valve, wherein at least one branch duct is positioned between the inlet and the central duct valve and wherein at least one branch duct is positioned between the outlet and the central duct valve. The device is arranged for carrying out single-column and (continuous) multicolumn chromatographic separations. This allows the purification of biopharmaceutical products without having to develop, demonstrate and validate cleaning procedures for the valves.

Abstract: New chiral stationary phases (CSPs) based on chiral selectors covalently bound on a solid support were prepared. Chiral selectors were obtained from enantiomerically pure aromatic amines and 3,5-dinitrobenzoic acid and then linked to the support surface through the allylic double bond. Such obtained materials allow enantioseparation of racemates or enantiomerically enriched compounds. These chiral stationary phases can be used as fillings in chromatographic columns for enantiomer separation of naproxen type drugs and other similar non-steroidal anti-inflammatory drugs (NSAID) by means of high performance liquid chromatography on both the analytical and preparative scale.

Abstract: In a liquid chromatography apparatus, a separation column of intermediate stage is additionally connected between a separation column of first stage and a separation column of second stage. Preferably, a switching unit and a liquid feed unit for mixing and feeding a plurality of solutions are added to improve a separation capability. A three-dimensional liquid chromatography apparatus capable of avoiding the “solution interference” can be realized. Even a complex sample containing a hydrophilic component and a hydrophobic component in a mixed state can be separated and analyzed satisfactorily on-line.

Abstract: Disclosed is a mixer-distributor-collector apparatus for use between beds of solid particles in a fluid-solid contacting vessel. The apparatus includes a solids retaining screen, fluid deflector, passageway, fluid distributor, and flow manipulator. The flow manipulator is a device such as a honeycomb, porous solid, perforated plate, screen, or grid having an open area greater than the open area of the fluid distributor and is located below and spaced apart from the fluid distributor. The apparatus improves the fluid flow characteristics by minimizing or eliminating fluid velocity jets and/or other turbulence which can disturb the downstream particle bed. In an exemplary application, the invention finds use in simulated moving bed (SMB) adsorptive separation processes.

Abstract: A method and device for increasing the loading capacity of a chromatography column through dilution of a mobile phase at the head of the column. A strong mobile phase is provided for dissolving a sample. A sample is injected into the strong mobile phase, and subsequently diluted with a weak mobile phase. The resulting sample-containing weak mobile phase is passed through a chromatography column for retention and separation of the components of the sample.

Abstract: Disclosed herein are an apparatus and a method for separating molecules on the basis of size and or structure, and to a method of making the apparatus. Generally, the separation method includes passing a fluid comprising particles having different effective molecular diameters through a plurality of open, nanoscale channels disposed in surfaces of substrates. The method also includes obtaining a plurality of fractions of the passed fluid such that each of the fractions includes a major portion containing particles having similar size and shape and substantially free of particles having larger size and shape. The apparatus includes first and second substrates each of which has a surface containing a plurality of open, nanoscale channels disposed therein. The surfaces are bonded together such that each of the channels of the first substrate is in fluid communication with at least two of the channels of the second substrate and is misaligned relative to the channels of the second substrate.

Abstract: The present invention relates to a simulated moving bed process, wherein at least one adsorbent is washed after binding of target compound and wherein the outlet of wash liquid from the adsorbent is subsequently passed onto another adsorbent for binding of target compound removed by the washing. In one embodiment, the method comprises binding of at least one target compound using three or more adsorbents connected in series and elution of target compound from said three adsorbents. After the binding to an adsorbent, wash liquid is passed across the adsorbent to recover desorbed and/or unbound target compound, and the outlet of such wash liquid is directed to the adsorbent after the next in the series, to which no feed has yet been added. The target compound is recovered by eluting target compound from the washed adsorbents.

Abstract: A method and device for increasing the loading capacity of a chromatography column through dilution of a mobile phase at the head of the column. A strong mobile phase is provided for dissolving a sample. A sample is injected into the strong mobile phase, and subsequently diluted with a weak mobile phase. The resulting sample-containing weak mobile phase is passed through a chromatography column for retention and separation of the components of the sample.

Abstract: The invention concerns a method for separating fractions of a mixture using a chromatography device. The method includes the following steps: controlling in one node of the device, the history of a specific variable of the fractions of the mixture to be separated; detecting one characteristic point of the history, the characteristic point being between two successive steps of fraction collecting; comparing the position of the characteristic point relative to a target position; adjusting the amount of mobile phase modifying the position of the characteristic point to cause the position of the characteristic point to coincide with the target position. The invention also concerns a device for implementing the method. The method enables the operation of the device to be automatically set.

Abstract: The disclosed HPLC flow schematic back-flushes the guard column with mobile phase once every operating cycle, the regular cleaning maintaining its effectiveness and useful life. This mobile phase flow reversal is accomplished by imposing a two position multiple port switching valve between the guard and separation columns. In one valve position, the mobile phase is pumped in one flow direction through both the separation and guard columns, but the switched valve maintains the same flow direction only through the separation column and reverses the mobile phase flow direction through the guard column, for effectively cleaning the guard column. Moreover, the mobile phase back flow is directed over the emptied sample drawing needle for cleaning it to reduce possible sample cross contamination. The improved flow circuits use basically only the typical HPLC system components, except for some insignificant modifications from existing injector designs.

Abstract: A circuit synchronizes the actuation of multi-dimensional separating valves with a system clock also coupled to a data acquisition circuit such that signals from a detector are synchronized and no signal information is lost. The system comprises an acquisition clock coupled to a data acquisition logic system and to a modulator valve control. The modulator valve control is, in turn, coupled to a multi-dimensional separation technique valve unit for controlling the valves for introduction of the eluant from a first separation column to a second, faster column in synchronism with acquisition of data by a detector.

Abstract: A process for continuous purification of a multi-component mixture by means of individual chromatographic columns though which the mixture is fed by means of at least one solvent. The multi-component mixture comprises at least light impurities, an intermediate product, and heavy impurities. The columns are grouped into at least four sections (?, ?, ?, ?) and the fourth section contains three sub-sections (?r, ?f, ?g). The process operates, alternatingly, in a batch-mode position and in an interconnected-mode position. After or within a switch time, the columns are moved in their function in a counter direction to the general direction of flow of the solvent. The combination of batch chromatography with elements of simulated moving bed techniques, or rather, countercurrent-principles, allows for the separation of a true multi-component mixture, even if one of the products is only present in a small amount, comparatively.