The invention relates to a method for purifying a target substance starting from a fluid to be treated which comprises at least one impurity, said method comprising the following steps: – provision of a stream of the fluid to be treated; – treatment of the stream of fluid to be treated using a chromatography step in a first separation unit (1); – collection of a fraction enriched with the target substance, in a first tank (4); – viral inactivation of the fraction enriched with the target substance, said viral inactivation comprising: passing the fraction enriched with the target substance collected in the first tank (1) through a second separation unit (2), via a bypass line (9); passing a viral inactivation solution through the second separation unit (2), via the bypass line (9); mixing the fraction enriched with the target substance and the viral inactivation solution; and collecting the mixture of the fraction enriched with the target substance and the viral inactivation solution, in the second tank (5); so as to obtain a fraction depleted of active virus; – treatment of the fraction depleted of active virus using a chromatography step in the second separation unit (2); and – collection of a fraction more enriched with the target substance, at the outlet of the second separation unit (2).
B01D 15/18 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives aux différents types d'écoulement
B01D 15/24 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives au traitement des fractions à répartir
B01D 15/36 - Adsorption sélective, p. ex. chromatographie caractérisée par le mécanisme de séparation impliquant une interaction ionique, p. ex. échange d'ions, paire d'ions, suppression d'ions ou exclusion d'ions
B01D 15/38 - Adsorption sélective, p. ex. chromatographie caractérisée par le mécanisme de séparation impliquant une interaction spécifique non couverte par un ou plusieurs des groupes , p. ex. chromatographie d'affinité, chromatographie d'échange par ligand ou chromatographie chirale
A61L 2/18 - Procédés ou appareils de désinfection ou de stérilisation de matériaux ou d'objets autres que les denrées alimentaires ou les lentilles de contactAccessoires à cet effet utilisant des substances chimiques des substances liquides
C07K 1/22 - Chromatographie d'affinité ou techniques analogues basées sur des procédés d'absorption sélective
A61L 2/00 - Procédés ou appareils de désinfection ou de stérilisation de matériaux ou d'objets autres que les denrées alimentaires ou les lentilles de contactAccessoires à cet effet
C07K 1/36 - ExtractionSéparationPurification par une combinaison de plusieurs procédés de types différents
The invention relates to a sugar processing method comprising, in a series: a first frontal filtration of a sugar juice in order to obtain a first filtrate; a second frontal filtration of the first filtrate in order to obtain a second filtrate; and bringing the second filtrate into contact with a cation-exchange chromatography resin so as to load the resin with divalent cations and to collect a sweetened sugar juice, the resin being arranged in the form of a bed that has a height h between 0.75 and 3 metres. The invention also relates to a sugar processing device.
The invention relates to a method for treating sugar comprising: - placing a coloured sugar juice in contact with an ion exchange resin so as to charge the resin with colouring agents and to collect a bleached sugar juice; - regenerating the colouring-charged resin, comprising: - placing the charged resin in contact with a regeneration brine comprising a chloride salt; and - collecting a regeneration effluent, the regeneration effluent comprising at least three fractions A, B and C, fraction A having a higher concentration of chloride salt than fractions B and C; and - recycling the regeneration effluent, comprising: - nanofiltration of fraction A of the regeneration effluent in order to obtain a first permeate and a first retentate; - diafiltration of the first retentate, said diafiltration comprising: - dilution of the first retentate with the fraction B of the regeneration effluent; - nanofiltration of the mixture in order to obtain a second permeate and a second retentate; - mixing of the first permeate with the second permeate and fraction C of the regeneration effluent, and evaporation of this mixture in order to obtain a final fraction; and - using the final fraction in order to supply regeneration brine.
B01J 49/70 - Régénération ou réactivation des échangeurs d'ionsAppareillage à cet effet pour les procédés ou les applications industriels à grande échelle
The invention relates to a method for the chromatographic purification of at least one cannabinoid compound, wherein the method comprises a main purification stage comprising the steps of:injecting an initial mixture comprising the at least one cannabinoid compound and one or more additional compounds onto a main stationary phase comprising silica particles, the silica particles comprising amino and/or diol groups;performing an elution with an elution solution, and collecting one or more elution fractions; and optionally, washing the main stationary phase with a washing solution and collecting one or more washing fractions; at least one of the elution fractions or washing fractions containing the at least one cannabinoid compound purified from the one or more additional compounds.
B01D 15/18 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives aux différents types d'écoulement
B01D 15/32 - Chromatographie en phase liée, p. ex. avec une phase normale liée, une phase inverse ou une interaction hydrophobe
A61K 31/352 - Composés hétérocycliques ayant l'oxygène comme seul hétéro-atome d'un cycle, p. ex. fungichromine ayant des cycles à six chaînons avec un oxygène comme seul hétéro-atome d'un cycle condensés avec des carbocycles, p. ex. cannabinols, méthanthéline
The invention concerns a method for purifying a mixture to be separated, in a multi-column chromatographic system, the method comprising successively, in a cyclic manner: - a step of collecting a refinement, a step of injecting the mixture to be separated, a step of collecting an extract and a step of injecting eluent, at an operating temperature; wherein the mixture to be separated has a viscosity at 20°C greater than or equal to 3 mPa.s; and wherein the mass concentration of dry matter of the mixture to be separated is equal to close to 5% at a threshold concentration, said threshold concentration being such that: - the viscosity of the mixture to be treated, at a mass concentration of dry matter equal to the threshold concentration and at the operating temperature, is equal to twice the viscosity of the mixture to be treated, at a mass concentration of dry matter equal to 85% of the threshold concentration and at the operating temperature.
B01D 15/18 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives aux différents types d'écoulement
B01D 15/36 - Adsorption sélective, p. ex. chromatographie caractérisée par le mécanisme de séparation impliquant une interaction ionique, p. ex. échange d'ions, paire d'ions, suppression d'ions ou exclusion d'ions
C13B 20/14 - Purification des jus sucrés utilisant des matériaux échangeurs d'ions
The invention relates to a method for producing a fructose composition comprising the following successive steps: - providing an initial composition comprising glucose; - concentrating the initial composition by evaporation of water in order to obtain a concentrated initial composition; - isomerising the glucose into fructose from the concentrated initial composition, whereby an intermediate composition is obtained; - purifying the intermediate composition in a multi-column chromatography system, whereby a raffinate which is rich in glucose and an extract which is rich in fructose are obtained; - concentrating the extract by evaporation of water; the intermediate composition not undergoing a step of concentrating by evaporation of water between the isomerisation step and the purification step.
B01D 15/18 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives aux différents types d'écoulement
B01D 15/36 - Adsorption sélective, p. ex. chromatographie caractérisée par le mécanisme de séparation impliquant une interaction ionique, p. ex. échange d'ions, paire d'ions, suppression d'ions ou exclusion d'ions
The invention relates to a method for purifying a mixture to be separated containing fructose, in a multi-column chromatography system, said method successively comprising, in a cyclical manner: a step of collecting a raffinate, a step of injecting the mixture to be separated, a step of collecting an extract and a step of injecting eluant; in which the mixture to be separated has a mass concentration of dry matter of between 45 and 55%, the method being implemented at a temperature of between 50 and 62°C.
B01D 15/18 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives aux différents types d'écoulement
B01D 15/36 - Adsorption sélective, p. ex. chromatographie caractérisée par le mécanisme de séparation impliquant une interaction ionique, p. ex. échange d'ions, paire d'ions, suppression d'ions ou exclusion d'ions
C13B 20/14 - Purification des jus sucrés utilisant des matériaux échangeurs d'ions
The invention relates to a method for chromatographic purification of an initial flow containing ammonium sulphate and 2-hydroxy-2-methylpropionic acid, comprising: - passing the initial flow over a stationary phase bed; - eluting a refinement enriched with ammonium sulphate and depleted of 2-hydroxy-2-methylpropionic acid; and - eluting an extract enriched with 2-hydroxy-2-methylpropionic acid and depleted of ammonium sulphate.
B01D 15/18 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives aux différents types d'écoulement
B01D 15/36 - Adsorption sélective, p. ex. chromatographie caractérisée par le mécanisme de séparation impliquant une interaction ionique, p. ex. échange d'ions, paire d'ions, suppression d'ions ou exclusion d'ions
B01J 41/20 - Échangeurs d'anions pour procédés chromatographiques
B01J 41/05 - Procédés utilisant des échangeurs organiques sous forme fortement basique
The invention relates to a method for separating a mixture in a system comprising a plurality of chromatography columns, the method successively comprising, in a cyclical manner, in a given part of the system: a step of collecting a raffinate; a step of injecting the mixture to be separated; a step of collecting an extract; and a step of injecting a mobile phase; the method further comprising: determining, in a node of the system, the history of a variable representing the concentration of at least one species contained in the mixture to be separated; detecting, within said history, a characteristic point between the beginning of a step of collecting the extract and the end of the following step of collecting the raffinate; comparing the position of the characteristic point in relation to a target position; and adjusting the carrier volume of the characteristic point, modifying the position of the characteristic point in order to bring the position of the characteristic point closer to the target position; the volume of the mobile phase injected per cycle being maintained higher than, or equal to, a minimum threshold and/or lower than, or equal to, a maximum threshold. The invention also relates to a computer program for carrying out the steps of such a method, to a storage medium on which such a program is recorded, and to a system comprising a processor coupled to a memory on which such a program is recorded.
B01D 15/18 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives aux différents types d'écoulement
The invention relates to a process for separating a mixture in a facility comprising: - a first system comprising a plurality of chromatography columns, an outlet line for collecting a raffinate and an outlet line for collecting an extract; - at least one second system placed downstream of the first system; and - at least one tank fed by one of said outlet lines from the first system, and feeding the second system with a continuous flow; wherein the process successively comprises, in a cyclical manner, in a given part of the first system: - a step of collecting a raffinate, a step of injecting the mixture to be separated, a step of collecting an extract and a step of injecting mobile phase; wherein the process comprises, moreover, measuring the purity and/or the yield of at least one collected fraction chosen from the extract and the raffinate, said purity and/or yield measurement comprising the following steps: - determining the concentration of at least two species of the mixture to be separated in the fraction collected in the tank; - determining the purity and/or the yield of at least one species of the fraction collected in the tank.
B01D 15/18 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives aux différents types d'écoulement
The invention relates to a process for separating a mixture in a system comprising a plurality of chromatography columns, wherein the process successively comprises, in a cyclical manner, in a given part of the system: - a step of collecting a raffinate, a step of injecting the mixture to be separated, a step of collecting an extract and a step of injecting mobile phase; wherein the process comprises, moreover, measuring the purity and/or the yield of at least one collected fraction chosen from the extract and the raffinate, said purity and/or yield measurement comprising the following steps: - determining, in a node of the system, the histories of at least two respective variables representative of the concentration of at least two species contained in the mixture to be separated, by means of at least one rapid online detector; -determining the concentration of at least two species of the mixture to be separated in the collected fraction, from the histories; - determining the purity and/or the yield of the collected fraction, from the concentrations.
B01D 15/18 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives aux différents types d'écoulement
The invention relates to a method for purifying a solution, the method comprising the following successive steps: – bringing a solution to be purified into contact with an ion exchange resin by suspending the ion exchange resin in the solution to be purified, the ion exchange resin having the form of particles having a size Dv50 smaller than or equal to 200 µm; – separating the solution into a purified solution and a loaded resin; – regenerating the loaded resin by passing at least one regenerating solution through a compact bed of loaded resin. The invention also relates to an assembly for implementing the method.
B01J 47/10 - Procédés d'échange d'ions en généralAppareillage à cet effet à substance échangeur d'ions mobileProcédés d'échange d'ions en généralAppareillage à cet effet à substance échangeur d'ions en suspension ou sous forme de lit fluidisé
B01D 15/02 - Procédés de séparation comportant le traitement de liquides par des adsorbants ou des absorbants solidesAppareillages pour ces procédés par des adsorbants en mouvement
C13B 20/14 - Purification des jus sucrés utilisant des matériaux échangeurs d'ions
B01J 49/05 - Régénération ou réactivation des échangeurs d'ionsAppareillage à cet effet des lits fixes
13.
USE OF COMPRESSED GAS FOR MOVING ELUENT APPLIED TO CHROMATOGRAPHY
The invention relates to a method for chromatographic separation, comprising at least one step of elution of species held on a stationary phase by means of an eluent, followed by a step of moving the eluent in contact with the stationary phase by means of a compressed gas. Preferably, the movement step takes place after a step of elution of the product(s) of interest and/or after a step of regeneration of the stationary phase.
B01D 15/20 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives au conditionnement de la matière adsorbante ou absorbante
B01D 15/40 - Adsorption sélective, p. ex. chromatographie caractérisée par le mécanisme de séparation utilisant un fluide supercritique comme phase mobile ou comme éluant
14.
METHOD FOR PURIFYING GLYCOL USED AS A HYDRATE INHIBITOR
The invention concerns a purification method comprising: - supplying a stream comprising a glycol, monovalent ions and multivalent ions; - treating said stream with ion exclusion chromatography comprising: ⋅ injecting the stream into a chromatographic unit comprising a stationary ion-exchange phase; ⋅ injecting an eluent into the chromatographic unit; ⋅ collecting a fraction exiting the chromatographic unit; the collected fraction being enriched in glycol and depleted in monovalent ions and multivalent ions relative to the stream. The invention also concerns a facility suitable for implementing said method, and the application of same in the regeneration of a hydrate inhibitor.
The invention relates to a fluid distributor (9, 10) for a column (1) comprising at least one cell (2) containing a bed of particles (3), the fluid distributor (9, 10) comprising: - a floor (11, 21) comprising at least one injection point (15, 25) providing a fluidic connection on either side thereof; - a layer of a resistive medium (12, 22) fixed on one face of the floor (11, 21), the resistive medium being permeable to the fluid; - a spacing device (13, 23) inserted between the floor (11, 21) and the layer of resistive medium (12, 22) and maintaining a space for the circulation of the fluid between the floor (11, 21) and the layer of resistive medium (12, 22). The invention also relates to a column, in particular a chromatography column, provided with this fluid distributor.
B01D 15/22 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives à la structure de la colonne
The invention relates to a process for purifying an amino acid from a starting mixture, in which the amino acid comprises an aromatic ring and has an acidity constant Ka, the process comprising: - a first step of bringing the starting mixture into contact with a strong cationic resin, at a pH greater than or equal to pKa; - a second step of eluting with an aqueous solution of eluent having a pH greater than the pH of the first step, making it possible to collect a stream enriched with the amino acid.
C07D 233/64 - Composés hétérocycliques contenant des cycles diazole-1, 3 ou diazole-1, 3 hydrogéné, non condensés avec d'autres cycles comportant deux liaisons doubles entre chaînons cycliques ou entre chaînons cycliques et chaînons non cycliques avec des radicaux hydrocarbonés substitués, liés aux atomes de carbone du cycle, p. ex. histidine
C07D 209/20 - Radicaux substitués par des atomes de carbone comportant trois liaisons à des hétéro-atomes, avec au plus une liaison à un halogène, p. ex. radicaux ester ou nitrile substitués en outre par des atomes d'azote, p. ex. tryptophane
17.
PURIFICATION OF FATTY ACIDS BY A CHROMATOGRAPHIC METHOD
The invention concerns a method for purifying a first fatty acid, particularly a first polyunsaturated fatty acid, based on an initial mixture further comprising at least one second fatty acid and one third fatty acid, the method comprising at least: a first step of liquid-phase chromatographic separation, based on the initial mixture, making it possible to retrieve both a first flow enriched with the first fatty acid and a flow enriched with the second fatty acid; a second step of liquid-phase chromatographic separation, based on the first flow enriched with the first fatty acid, making it possible to retrieve both a second flow enriched with the first fatty acid and a flow enriched with the third fatty acid, the second step of chromatographic separation being carried out in a static-bed chromatographic separation unit.
B01D 15/18 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives aux différents types d'écoulement
C07C 51/47 - SéparationPurificationStabilisationEmploi d'additifs par traitement solide-liquideSéparationPurificationStabilisationEmploi d'additifs par absorption-adsorption chimique
The invention relates to a method for purifying a first polyunsaturated fatty acid based on an initial mixture, the initial mixture comprising at least one second fatty acid in addition to the first polyunsaturated fatty acid, the method comprising: at least one step of liquid-phase chromatographic separation of the first polyunsaturated fatty acid and the second polyunsaturated fatty acid, making it possible to retrieve both a flow enriched with the first polyunsaturated fatty acid and a flow enriched with the second fatty acid; and a step of treating the flow enriched with the first polyunsaturated fatty acid, leading to a reduction in the peroxide value and/or the anisidine value of said flow. The invention also relates to a facility for implementing said method.
The invention pertains to a method for purifying a first fatty acid, preferably polyunsaturated, based on an initial mixture further comprising at least one second fatty acid, optionally a third fatty acid, and optionally a fourth fatty acid, the method comprising: a first step of liquid-phase chromatographic purification, based on the initial mixture, carried out in a first chromatographic separation unit, making it possible to retrieve both a first flow enriched with the first fatty acid and a flow enriched with the second fatty acid; optionally, a second step of liquid-phase chromatographic purification, based on the first flow enriched with the first fatty acid, carried out in a second chromatographic separation unit, making it possible to retrieve both a second flow enriched with the first fatty acid and a flow enriched with the third fatty acid; optionally, a third step of liquid-phase chromatographic separation, based on the third flow enriched with the first fatty acid, carried out in a third chromatographic separation unit, making it possible to retrieve both a third flow enriched with the first fatty acid and a flow enriched with a fourth fatty acid; at least one of the first chromatographic separation unit, the second chromatographic separation unit and the third chromatographic separation unit being a static-bed, single-column chromatographic separation unit with steady-state recirculation.
B01D 15/18 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives aux différents types d'écoulement
C07C 51/47 - SéparationPurificationStabilisationEmploi d'additifs par traitement solide-liquideSéparationPurificationStabilisationEmploi d'additifs par absorption-adsorption chimique
The invention relates to a method for purifying a first polyunsaturated fatty acid based on an initial mixture, the initial mixture comprising at least one second fatty acid in addition to the first polyunsaturated fatty acid, the method comprising: at least one step of liquid-phase chromatographic separation of the first polyunsaturated fatty acid and the second polyunsaturated fatty acid, making it possible to retrieve both a flow enriched with the first polyunsaturated fatty acid and a flow enriched with the second fatty acid; and a step of treating the flow enriched with the first polyunsaturated fatty acid, leading to a reduction in the peroxide value and/or the anisidine value of said flow. The invention also relates to a facility for implementing said method.
This invention relates to a process for the enrichment of isotopes by chromatography on a saturated stationary phase. The process provides a more efficient method than the existing methods.
This invention relates to a process for the enrichment of isotopes by chromatography on a saturated stationary phase. The process provides a more efficient method than the existing methods.
The invention relates to a method of separating fractions of a mixture to be separated, comprising the following step: provision of a device comprising at least two chromatography columns connected in series; discontinuous injection of the mixture to be separated, at a single point in the device; discontinuous withdrawal of the fraction enriched with the product of interest, at a single point in the device; and injection of eluants into each column and displacement of the eluant injection points, the eluants having different eluting strengths. The method allows effective and easily implementable separation.
B01D 15/18 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives aux différents types d'écoulement
G01N 30/46 - Modèles d'écoulement utilisant plus d'une colonne
The invention relates to a method for the continuous crystallisation of a mixture of stereo-isomers and a resolution agent in a solvent, said mixture and resolution agent being injected into a continuously stirred reactor and the crystallised stereo-isomer salt being recovered continuously.
C07C 255/24 - Nitriles d'acides carboxyliques ayant des groupes cyano liés à des atomes de carbone acycliques contenant des groupes cyano et des atomes d'azote, liés par des liaisons simples et n'étant pas liés de plus à d'autres hétéro-atomes, liés au même squelette carboné acyclique saturé
C07B 57/00 - Séparation de composés organiques optiquement actifs
The invention relates to a method for separating compounds in the load of a chromatography device comprising a load loop, characterised in that the loop is movable between a load loading position and a load injection position into the device, and is maintained under a pressure higher than the atmospheric pressure in the different positions. The invention is used for preventing a pressure variation that would be detrimental to the device and the separation method.
B01D 15/08 - Adsorption sélective, p. ex. chromatographie
B01D 15/14 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives à l'introduction de l'alimentation dans l'appareil
B01D 15/18 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives aux différents types d'écoulement
G01N 30/20 - Injection utilisant une valve d'échantillonnage
G01N 30/22 - Injection dans des systèmes liquides à haute pression
G01N 30/32 - Contrôle des paramètres physiques du fluide vecteur de la pression ou de la vitesse
26.
METHOD FOR ENRICHING ONE OR MORE COMPOUNDS OF A MIXTURE USING A LIQUID MOBILE PHASE CONTAINING A GAS
The subject matter of the invention is a method for enriching one or more compounds of a mixture by chromatography in at least one column using an eluent, characterized in that a liquid mobile phase containing dissolved gas is used as the eluent. The subject matter of the invention also relates to the use of an eluent consisting of a liquid mobile phase containing a dissolved gas in preparative chromatography.
G01N 30/34 - Contrôle des paramètres physiques du fluide vecteur de la composition du fluide, p. ex. du gradient
B01D 15/16 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives au conditionnement du fluide vecteur
G01N 30/36 - Contrôle des paramètres physiques du fluide vecteur dans les systèmes liquides à haute pression
B01D 15/40 - Adsorption sélective, p. ex. chromatographie caractérisée par le mécanisme de séparation utilisant un fluide supercritique comme phase mobile ou comme éluant
B01D 15/12 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives à la préparation de l'alimentation
27.
METHOD FOR ENRICHING ONE OR MORE COMPOUNDS OF A MIXTURE USING A LIQUID MOBILE PHASE CONTAINING A GAS
The object of the invention is a method for enriching by chromatography of one or more compounds of a mixture in at least one column using an eluent, characterized in that a liquid mobile phase containing dissolved gas is used as eluent. A further object of the invention in the use in preparative chromatography of an eluent composed of a liquid mobile phase containing a dissolved gas.
G01N 30/34 - Contrôle des paramètres physiques du fluide vecteur de la composition du fluide, p. ex. du gradient
B01D 15/16 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives au conditionnement du fluide vecteur
G01N 30/36 - Contrôle des paramètres physiques du fluide vecteur dans les systèmes liquides à haute pression
B01D 15/40 - Adsorption sélective, p. ex. chromatographie caractérisée par le mécanisme de séparation utilisant un fluide supercritique comme phase mobile ou comme éluant
B01D 15/12 - Adsorption sélective, p. ex. chromatographie caractérisée par des caractéristiques de structure ou de fonctionnement relatives à la préparation de l'alimentation
brevets
