Device for the chromatographic separation of mixtures of gases and vapors
(57) Abstract:The invention relates to a device for separating mixtures of gases and vapors by gas chromatography. The device contains three chromatographic column. One of the columns is used for the regeneration of the sorbent layer from the heavy fraction of the mixture, and the other two are for the separation of mixtures and output light fraction. The columns are connected to each other transitional channels. The column is divided into sections, each of which is filled with selective components shared substance sorbent. Enter the carrier gas is carried out with the first section and the outlet from the last section in the idler channel passing through a column filled with a layer of stationary sorbent. The technical result of the present invention is expressed in increasing productivity and increase the purity of the fractions. 2 Il. The invention relates to a device for separating mixtures of gases and vapors by gas chromatography.Known chromatograph "standard-2"  which represents the automatic installation cyclic actions intended for chromatographic selection of one of the target product. As the source can be used liquid mixture temperature is s equipment. The lack of similar is the use of chromatographic columns with a fixed bed of sorbent, reducing the separation efficiency with increasing diameter.A device for chromatographic separation of binary gas mixtures , containing three chromatographic columns, one of which serves for regeneration of a layer of sorbent from the heavy fraction of the mixture, and the other two are for the separation of mixtures and output light fraction. The chromatographic column are connected to each other transitional channels that have switching elements, each of the columns of additional gas channels with installed managed switching elements connected with a source of partial mixture and system receivers to collect fractions. A disadvantage of the known device is the use of chromatographic columns with a fixed bed of the sorbent at a given purity of the secreted product.The aim of the invention is to improve the performance and increase the purity of the fractions.This objective is achieved in that the device for the chromatographic separation of mixtures of gases and vapors containing three chromatographic Colo the Oia mix and output partial fractions, connected to each other transitional channels that have switching elements, each of the columns of additional gas channels with installed managed switching elements connected with a source of partial mixture and system receivers to collect fractions, the column is divided into sections, each of which is filled with selective components shared substance sorbent, movable under the pressure of the carrier gas enter the carrier gas is carried out with the first section and the outlet from the last section in the idler channel passing through a column filled with a layer of stationary sorbent. The device can operate in combined mode with movable and fixed bed of the sorbent when filled with sorbent drainage channels in the columns.In Fig.1 shows the principle of the gas circuit of the device of Fig.2 - scheme of travel separable mixtures along the columns.The device comprises a chromatographic column 1, 2, 3, separated nets in sections 4, 5, 6, each of which is filled with sorbent, allowing you to work in a fluidized bed mode, part of the cross section of the columns in the form of drainage channels 7, 8, 9, the last section of the column output shared with the de compact diaphragm valves 13, 14, 15, operated by means of compressed air.For the supply and withdrawal of gas flows in each column is provided by the channels 16, the managed switching elements 17, such as diaphragm valves.At the initial moment of the flow of carrier gas (w2), supporting the sorbent in a fluidized bed mode of the common collector 18 is input to the chromatographic column 1, through its regeneration from the heavy fraction during this transition channel 12 between columns 1 and 3 is blocked by the valve 15. With the last section of the column flow through the outlet channel 7 is returned to the beginning of the column and part of it (w1) is discharged into the reservoir 19 to collect the heavy fraction of the mixture. The remaining part of the flow (w2- w1) passes through the column 2 and 3 and output column 3 is directed into a manifold 20 for collecting light fraction separable mixtures.When a steady flow of carrier gas carry pulse input portions separable mixtures (see Fig.2, a) by briefly opening the valve, is installed on the channel connecting the inlet of column 3 with the manifold 21. The reservoir 21 is filled partial gaseous mixture under pressure higher than the pressure of the carrier gas in the column. Introduction the direction of either a thread exit w2the carrier gas. In that moment of time when a particular section of the moving of the chromatographic strip (shaded in the diagram area) will be half the length of the column 3 (see Fig.2, b), automatically switch the valves on the channels for the supply and withdrawal of gas flows, with designated input and output a carrier gas to move along the columns by a distance equal to the length of one column (see Fig.2). In this position, the carrier gas (flow w2) is input to column 2, through its regeneration. The valve 13 in a transitional channel between columns 1 and 2 overlap, and the column outlet 3 is connected to the input of the column 1. In this part of the flow of carrier gas (w1after passing through the column 2 is discharged into the reservoir 19 to collect the heavy fraction of the mixture, and the remainder of the stream (w2-w1) passes through the column 3 and 1 and is displayed in the header 20 for collecting the light fraction of the mixture.w1the flow rate of the carrier gas, corresponding to the beginning of fluidization of the adsorbent,
w2the flow rate of the carrier gas, corresponding to the end of fluidization of the adsorbent, and w2-w1w1< / BR>Chromatographic strip, where there is a separation of mixture components for which 2 - w1) carrier gas. When the average cross section of the chromatographic strip will pass through the column 3 and will move to column 1 (see Fig.2) produce a pulse input a fresh portion of the mixture in this section. After the average total cross section of the chromatographic strip formed after two consecutive inputs portions of the mixture will be half the length of the column 1 (see Fig.2, d), move the points of the input and output of the carrier gas along the columns by a distance equal to the length of one column (see Fig.2, d). With the valve block 14 transition channel between the columns 2 and 3 and simultaneously the column outlet 1 connect to the input of the column 2. In this position, the flow of carrier gas (w2is entered to the input column 3, through its regeneration, and part of w1stream is output from the output of the column in the reservoir 19 to collect the heavy fraction of the mixture, and the remainder of w2-w1flow out from the column 2 in the manifold 20 for collecting the light fraction of the mixture.Thus, at each phase of the cycle of the chromatographic strip through the three columns, one column at maximum speed in a carrier gas w2- implemented regeneration from the heavy fraction, and the other two are used to and separable mixtures, and the tail - heavy, moves in a flow of carrier gas along the layer of sorbent and gradually moves from column 1 to column 2. When the average cross section of the chromatographic strip, the concentration of the partial components which are close to the concentration of the components in the original mixture, passed through the column 1 and starts to move in column 2, to produce a pulse input a fresh portion of the mixture in the transition channel (see Fig.2, d).The total chromatographic strip continues to move with the flow of carrier gas from the column 1 to column 2, and when the average cross-section it will be half the length of the column 2 (see Fig.2, e), move the point of input and output gas flows in the direction of movement of the chromatographic strip by a distance equal to the length of the column. Simultaneously with the shifting of the input and output gas flow outlet of the column 2 is connected with the inlet of the column 3, and the transition channel between columns 1 and 3 overlap. In this position (see Fig. 2, and the carrier gas is fed to the input of the column 1, after passing through that part of w1flow is discharged into manifold 19 for collecting the heavy fraction, the other part of w2-w1flow passes through the column 2 and 3 and is output from the column outlet 3 in number, the cycle of movement of the points of input and output gas flows and cycles of recharge chromatographic strip fresh portions separable mixtures are repeated in the described sequence.The process is carried out without selection of the partial components of the mixture as long as the total length of the chromatographic strip the layer of sorbent in the process of its circulation, accompanied by the expansion of her will not be equal to the length of the column. Starting from this moment, every movement places the input and output gas flows in the direction of movement of the chromatographic strip is accompanied by a selection of the products with the end parts of the strip, enriched by shared components.For example, if the schema is in the position shown in Fig.2, e, in which the width of the chromatographic strip the layer of sorbent is greater than the length of the column, by that time the front part of the chromatographic strip, enriched in the light component, will take place column 2 and will be eliminated by the flow of carrier gas into the reservoir 20 for collecting the light fraction. Remaining in column 1 of the rear portion of the chromatographic strip, enriched in the heavy component in the next moment when the moving location of the input and output of the carrier gas from the state is the use of points of input and output gas flows in the direction of movement of the chromatographic strip is equal to the time for which the average cross-section of the chromatographic strip passes a distance equal to the length of the column. It can be easily determined from preliminary experiments on periodic separation of portions of the mixture. The time interval between the moments move places the input and output flow of the carrier gas and the time of filing a fresh portion of the mixture in the middle section of the chromatographic strip is equal to half the time interval between two subsequent points of displacement of the input and output.The ratio of the speeds of parts of w1and w2-w1the flow of carrier gas that is output from the speakers is selected depending on whether the mixture is separated. In all cases, the speed of movement of the rear border of the chromatographic strip in the stream w2the carrier gas must be greater than the speed of movement of the anterior border of the chromatographic strip in the stream w2-w1and w1.The device (see Fig.1) also contains devices 22 and 23 for separating components of a partial mixture of the carrier gas from gas streams that are output from the collectors 19 and 20 for selection of heavy and light fractions of the mixture. Separated from the product stream of carrier gas through the circulation pump 24 return in collaku delivery device 27 is introduced into the system 28 for the preparation of a partial mixture, which may include an evaporator for evaporating the liquid (if a partial mixture of liquid) or a device for heating gas to the temperature of the column (if the partial gaseous mixture). The gas circuit of the device consists of regulators speeds threads 29 and 30, mounted at the outlet of the collectors 19 and 20, the adjustable choke 31 and a pressure gauge 32 for measuring the pressure of the carrier gas and other elements designed to maintain the specified conditions of the separation column. In addition, to compensate for loss of carrier gas from a closed system device has a source 33 of carrier gas, such as compressed inert gas. The flow of carrier gas from a source 33, controlled rheometer 34, is fed continuously to the device, connecting with the flow of the carrier gas directed from the output of the circulation pump 24.Through the use of part of the volume of the column at the outlet channel is provided by the upward flow of carrier gas, which enables the application in the schema column fluidized bed of sorbent (PS), with a weaker dependence WATT of the diameter, the lower hydraulic resistance at high flow rates, facilitating heat removal from powernote chromatographic separation. Use a portion of the volume of the column at the outlet channel and filling it fixed bed of sorbent provides homogenization of flow, increases the radial diffusion in the fluidized bed of sorbent, thereby increasing the efficiency of the separation, and hence the purity of the secreted fractions.Testing of the device is held on the chromatograph Etalon - 2 column with a diameter of 103 mm, filled fixed bed of sorbent Silagra C-80 fraction of 0.35-0.5 mm and a column with a diameter of 103 mm, mounted on an axis lateral channel with a diameter of 50 mm, in which the gap between the tubes was divided into sections to a height of 60 mm, each of which was filled with the same adsorbent Silagra C-80 fraction of 0.35-0.5 mm to a height of 40 mm, providing enhanced sorption layer, and an outlet channel was filled with the adsorbent, forming a fixed layer. When comparing kept under equal volume of the adsorbent columns. Tests were conducted on model mixtures containing equal amounts of hexane and heptane, at a temperature of the evaporator 90oC, column 70oC, as a carrier gas was used to dry the cleaned air.The experiments showed that at a constant value resolution coefficients naked, the, is 25% higher than the fixed bed of adsorbent.Sources of information
1. Prospect Auto preparative gas chromatograph the standard 2" by okba,, Dzerzhinsk, Nizhny Novgorod region, 1968.2. USSR author's certificate N 309296, CL G 01 N 31/08 - prototype. Device for the chromatographic separation of mixtures of gases and vapors containing three chromatographic columns, one of which serves for regeneration of a layer of sorbent from the heavy fraction of the mixture, and the other two are for the separation of mixtures and output partial fractions, connected to each other transitional channels that have switching elements, each of the columns of additional gas channels with installed managed switching elements connected with a source of partial mixture and receivers to collect fractions, characterized in that the column is divided into sections, each of which is filled with selective components shared substance sorbent, movable under the pressure of the carrier gas enter the carrier gas is carried out with the first section and the outlet from the last section in the idler channel passing through a column filled with a layer of stationary sorbent.
FIELD: chemical engineering; medical engineering.
SUBSTANCE: method involves plotting two chromatograms one of which is based on radioactivity (No 1) and the other one on ultraviolet absorption (No 2) or on radioactivity (No 1) and on fluorescence (No 2) and chromatogram specific relative to ultraviolet absorption (No 3) or relative to fluorescence (No 3). Material quality is estimated to be the more high the more close studied labeled compound peak shape is to trapezoid shape on the third chromatogram.
EFFECT: high accuracy of the method.
FIELD: analytical chemistry, ecology, in particular controlling of environmental air.
SUBSTANCE: claimed method includes aspiration if air sample through chemosorbtive medium, elution of formed dimethylamine salt, eluate closure with alkali, and gas chromatography analysis of gas phase with flame-ionization detection. Dimethylamine salt elution from adsorbent is carried out with 1 cm3 of distillated water; closured with alkali eluate is held in thermostat for 5 min; and as filling in separating chromatography column chromosorb 103, containing 5 % of PEG-20000 and treated with 20 % hexamethyldisilazane solution is used.
EFFECT: method for dimethylamine detection with improved sensibility and accuracy.
FIELD: chemical industry.
SUBSTANCE: during process of taking sample from technological pipe-line, absorption of water vapors and nitrogen oxides (II) and (IV) are conducted simultaneously. For the purpose the chemical agents are used which don't absorb nitrogen oxide and don't react with it. Chromatographic measurement of volume fraction of nitrogen oxide (I) is carried out by means of industrial chromatograph having heat-conductance detector by using column of thickness of 5 m and diameter of 3 mm. The column is filled with polysorbent; temperature of column's thermostat is 20-30 C and temperature of evaporator is 100C. Hydrogen is used as a gas-carrier. Concentrations of nitrogen oxide, measured by the method, belong to range of 0, 05-0, 50% of volume fraction. Method excludes aggressive affect of corrosion-active components on sensitive parts of chromatograph. Method can be used under industrial conditions for revealing factors influencing process of forming of nitrogen oxide at the stage of catalytic oxidation of ammonia and searching for optimal conditions for minimizing effluent of ammonia into atmosphere.
EFFECT: high reproduction; simplification; improved efficiency of operation.
FIELD: oil and gas production.
SUBSTANCE: aim of invention is estimating expectations for oil and gas of oil-source rock areas. For that aim, sampled rock is treated to isolate organic substance soluble in organic solvents, after which organic substance is chromatographed to detect 4-methyldibenzothiophene and 1-methyldibenzothiophene. When ratio of 4- to 1-isomer exceeds 0.9 rock is regarded as ripened.
EFFECT: increased determination reliability and rapidity.
SUBSTANCE: in the method, hard carrier with system of narrow pores and channels is kept under temperature below height of potential barriers for movement of at least one type of separated molecules.
EFFECT: higher efficiency.
FIELD: investigating or analyzing materials.
SUBSTANCE: gas analyzer comprises chromatographic columns, detectors, unit for preparing air mounted inside the thermostat, unit for control and processing signals, member for sampling, switches of gas flows, pump for pumping gas mixture, and separating passages connected in parallel and provided with the check valve interposed between them. Each of the separating passages is made of absorbing and separating chromatographic columns connected in series, and the pump is connected to the input of the gas line through the electric valve. The gas analyzer can be made of two separating passages and low pressure chromatographic columns.
EFFECT: enhanced quality of analyzing.
2 cl, 1 dwg, 1 ex
FIELD: analytical methods.
SUBSTANCE: to determine methyl alcohol in water, sample to be assayed is preliminarily subjected to distillation with sulfuric acid added in amount required to provide its concentration in mixture to be distilled c(1/2 H2SO4) = 0.002 M, while strippings constitute 6-7% of the volume of sample. Stripped liquid is thrice rinsed with hexane or Nefras at 1:1 hexane (Nefras)-to-strippings ratio. Rinsed material is then introduced into packed column filled with diatomite modified with 1,2,3-tris(β-cyanoethoxy)propane having deposited fixed phase thereon, which phase is prepared by way of consecutively keeping glycerol each time for 4 h at ambient temperature, 100°C, 130°C, 160°C, and 200°C, and then for 8 h at 230°C and for 40 h at 200°C under nitrogen bubbling conditions. Calculation of methanol content is performed taking into consideration calibrating coefficient.
EFFECT: enabled determination of small concentrations of methyl alcohol in water with sufficient selectivity and reliability.
2 cl, 2 tbl, 6 ex
FIELD: analytical chemistry.
SUBSTANCE: invention relates to method for quantitative determination of thiotriazoline and pyracetam in complex drugs by high performance chromatography, wherein silicagel with grafted 3-(chlorodimethyl)-propyl-N-dodecylcarbamate having particle size of 5 mum is used as sorbent; and degassed 0.05 M aqueous solution of potassium dihydrophosphate is used as mobile phase. Mobile phase velocity is 1 ml/min, and column temperature is 30°C. Method of present invention makes it possible to determine content of two abovementioned active ingredients simultaneously.
EFFECT: simplified process of sample preparation.
3 ex, 3 tbl
FIELD: biotechnology, in particular content determination of polymer chitosan molecules, chitosan-chitine polymer molecules and molecules of chitosan-protein complex in finished form of chitosan.
SUBSTANCE: claimed method includes application of high performance chromatography column filled with polyvinylbenzene sorbent with refractometer detector. As eluent and for dissolving of chitosan preparation samples acetic acid aqueous solution is used. Chain-length distribution is determined on the base of first chromatography peak, and polymer molecular content is calculated on the base of area of first, second and third chromatography peaks, divided up to zero line and belonging to polymer chitosan molecules, chitosan-chitine polymer molecules and molecules of chitosan-protein complex, respectively. To calculate chain-length distribution of polymer chitosan molecules separately calibration curve is plotted using dextran polymer standards.
EFFECT: new effective method for determination of polymer chitosan molecules in chitosan preparations.
4 cl, 3 dwg
FIELD: the invention refers to laboratory chromatographic devices for conducting high-speed chromatographic analysis.
SUBSTANCE: the express-chromatron has an injector, a chromatographic column located in a thermostat, a detector, an amplifier of the signal of the detector, an analog-digital converter, a control system, a pneumatic system. The column is fulfilled either in the shape of a short capillary column or either in the shape of a polycapillary column. The injector is fulfilled with possibility of introduction of the test for the time of 5-50 ms. The detector and the amplifier of its signal are fulfilled with possibility of ensuring constant time of no worse then 10-3 sec. The analog-digital converter is fulfilled with possibility of ensuring speed of no less then 200 measurements in a second.
EFFECT: ensures conducting high-speed chromatographic analysis.
11 cl, 2 dwg