Device for measuring the amount of mixed gas adsorbed by materials and transfer weighing method

Abstract

The present invention discloses a device for measuring the adsorption amount of mixed gas of a material and a transfer weighing method. The device includes a gas supply unit and an adsorption unit connected in sequence through a pipeline, and also includes a pure gas unit, a desorption unit and a detection unit connected to the adsorption unit through pipelines respectively. The gas supply unit includes a raw gas cylinder and valve assembly I, valve assembly II and valve assembly III, the adsorption unit includes an adsorbent column tube and valve assembly IV, the pure gas unit includes valve assembly V and a high-purity gas cylinder, the desorption unit includes valve assembly VI and several buffer gas cylinders, and the detection unit includes valve assembly VII and a chromatograph. The transfer weighing method utilizes the aforementioned device to provide a mixed gas through the gas supply unit, and after dynamic adsorption equilibrium, the adsorbed gas is completely desorbed and transferred to the buffer gas cylinder for weighing measurement. The measuring device and method effectively avoid the influence of factors such as gas buoyancy in the existing weight method, and effectively improve the accuracy of adsorption measurement.

Description

Technical Field

[0001] The invention belongs to the field of measurement technology and relates to the determination of gas adsorption, and in particular to a device for measuring the adsorption of mixed gas of a material and a transfer weighing method. Background Art

[0002] In recent years, with the extensive application of adsorption materials such as adsorbents, catalysts, battery materials, composite materials and powdered metals in various industries, the surface and interface physical property testing of materials has become more and more common. Among them, the adsorption amount is an important parameter reflecting the characteristics of the material. For example, by measuring the adsorption amount, the adsorption rate, pore diffusion coefficient and mass transfer coefficient of the material can be obtained; by measuring the adsorption amount of nitrogen at different pressures at liquid nitrogen temperature, the specific surface area, pore volume and pore size distribution of the adsorption material can be obtained; combined with gas chromatography, the adsorption amount of multi-components can be measured to calculate the separation coefficient of the adsorption material for different gases. The adsorption amount refers to the mass of the adsorbate (or the amount of substance) per unit mass of the adsorbent or per unit surface area of ​​the adsorbent, and is the main parameter of the adsorption performance of the reaction material.

[0003] Common methods for determining the amount of gas adsorption are the volumetric method and the gravimetric method. The volumetric method is to calculate the amount of adsorbed gas by measuring the pressure P and volume V of the gas before and after contact with a certain mass of adsorbent at a certain temperature. The volumetric method requires accurate measurement of parameters such as PVTZ, and the measurement accuracy is affected by the accuracy of the PVT sensor and the installation accuracy. The V value is calculated based on non-adsorbed helium, which is not very accurate and has a large difference from the actual value. The measurement results of different laboratories also vary greatly. The gravimetric method calculates the amount of adsorbed gas by directly measuring the weight change of the adsorbent during the adsorption process. The gravimetric measurement is affected by the accuracy of the spring scale, the buoyancy of the gas and the temperature difference. The accuracy is not high, and the error may be greater than the volumetric method.

[0004] The existing inspection of material adsorption performance and the measurement equipment of material gas adsorption can usually only measure the adsorption of a single pure gas by the material, but cannot meet the requirements of the adsorption of mixed gases by the measured material. In actual production applications, it is usually necessary to use adsorption materials to adsorb multi-component mixed gases to achieve the purpose of refining and obtaining high-purity gases. For example, in the production of helium refining, it is necessary to adsorb a variety of impurity gases (Ne / H2 / O2 / N2, etc.) in crude helium to obtain high-purity helium. There is competitive adsorption between different components in the mixed gas, so only the pure gas adsorption of the material is measured, which cannot meet the requirements of actual production for judging the adsorption performance of the material. Summary of the invention

[0005] In view of the fact that the volumetric method and gravimetric method conventionally used in the prior art for measuring gas adsorption have low accuracy and large errors, and the existing testing devices can only measure the adsorption of a single gas, the purpose of the present invention is to solve the above problems and provide a device for measuring the adsorption of mixed gases of materials and a transfer weighing method. The measuring device provides a mixed gas by setting a gas supply unit, and after dynamic adsorption equilibrium, the adsorbed gas is completely desorbed and transferred to a buffer gas bottle for weighing measurement. After the transfer, it is weighed again and the content of each component is analyzed by chromatography, which effectively avoids the influence of gas buoyancy and temperature difference on symmetry in the existing gravimetric method, thereby effectively improving the measurement accuracy of the adsorption amount and reducing the measurement error.

[0006] To achieve the above-mentioned object, the present invention provides a device for measuring the adsorption amount of mixed gas of a material, comprising a gas supply unit and an adsorption unit connected in sequence through a pipeline, and also comprising a pure gas unit, a desorption gas buffer unit and a detection unit respectively connected to the adsorption unit through pipelines;

[0007] The gas supply unit includes a raw gas cylinder for providing mixed gas and a valve assembly I, a valve assembly II and a valve assembly III connected to the raw gas cylinder in sequence through a pipeline, and the mixed gas passes through the valve assembly I, the valve assembly II and the valve assembly III in sequence to adjust the flow rate and pressure;

[0008] The adsorption unit comprises an adsorbent column tube whose two ends are respectively connected to the gas outlet end of valve component I and the gas outlet end of valve component II through pipelines, and a valve component IV, wherein the valve component IV is installed on the pipelines at the gas inlet and gas outlet ends of the adsorbent column tube to seal the adsorbent column tube when the adsorption is saturated; the mixed gas can enter the adsorption unit through the valve component I and then be discharged through the valve component III;

[0009] The pure gas unit comprises a valve assembly V and a high-purity gas cylinder which are sequentially connected to the gas inlet end of the adsorbent column tube through a pipeline, the high-purity gas cylinder is used to provide high-purity gas, and the high-purity gas enters the adsorption unit through the valve assembly V;

[0010] The desorbed gas buffer unit comprises a valve assembly VI and a plurality of buffer gas bottles which are sequentially connected to the gas outlet end of the adsorbent column tube through a pipeline. The adsorbent column tube desorbs gas at a gas desorption temperature, and under the suction effect of the reduced pressure or negative pressure of the buffer gas bottle, the desorbed gas is transferred through the valve assembly VI and stored in the buffer gas bottle.

[0011] The detection unit includes a valve component VII and a chromatograph which are sequentially connected to the valve component VI through a pipeline. The outlet gas of the adsorbent column enters the buffer gas bottle or the detection unit through the valve component VI. The chromatograph is used to detect whether the adsorption of the adsorbent column is saturated and to measure the content of the mixed gas components in the buffer gas bottle.

[0012] The above-mentioned device for measuring the adsorption amount of mixed gas of the material is designed according to the actual demand in the production process. When the diameter of the pipe used is large, in order to enable the gas to be adsorbed to be quickly cooled to the corresponding adsorption temperature when it reaches the adsorbent column, the measuring device preferably also includes a precooling pipe, which is arranged around the connecting pipe between the valve assembly I and the adsorption unit. The precooling pipe can cool the gas to be adsorbed in advance, so as to achieve the effect of rapid cooling when it reaches the adsorbent column.

[0013] The above-mentioned device for measuring the adsorption amount of mixed gas of the material, the main factors affecting the adsorption amount are gas pressure, gas flow rate and adsorption temperature. The adsorption temperature is mainly determined by the temperature control of the adsorbent column tube, and the gas pressure and gas flow rate are mainly controlled by the valve assembly. Therefore, each valve assembly is mainly used to control the flow, gas pressure and flow rate of the gas to be treated. In the present invention, the valve assembly I preferably includes a pressure reducing valve I, a needle valve I and a pneumatic valve I installed in sequence on the connecting pipe between the raw gas cylinder and the adsorbent column tube. The main function of the valve assembly II is to allow the mixed gas to enter the valve assembly III directly from the raw gas cylinder through it before the adsorption starts to adjust the gas flow rate and adsorption pressure. The valve assembly II preferably includes a pneumatic valve II. The main function of the valve assembly III is to control the flow rate and on-off of the mixed gas in the initial state setting and the dynamic adsorption process, so that the gas can be discharged safely. The valve assembly III preferably includes a pneumatic valve III, a needle valve II, a stop valve I, a stop valve II, a flowmeter and a stop valve III connected in sequence through a pipeline. Pressure reducing valve I is used to adjust gas pressure and keep gas pressure stable; needle valve itself has the function of cutting off fluid, but its more important function is to accurately adjust fluid flow. Here, needle valve I and needle valve II are mainly used to adjust gas flow; each pneumatic valve (I / II / III) is used to control the flow of gas. Each stop valve (I / II / III) controls the on and off of gas by opening and closing.

[0014] In the above-mentioned device for measuring the adsorption amount of mixed gas of a material, during the dynamic adsorption of gas, the temperature of the gas coming out of the adsorbent column tube is relatively low. In order to reduce the cold resistance requirements for the valve and thus reduce the cost, the measuring device preferably also includes a reheating tube, which is arranged around the pipeline between the pneumatic valve III and the needle valve II. The reheating tube can heat the gas coming out of the adsorption to restore the gas to room temperature or other set temperature, thereby reducing the performance requirements for the valve, and each valve can use a conventional valve.

[0015] In the above-mentioned device for measuring the adsorption amount of mixed gas of a material, the valve assembly IV is mainly used to control the on-off of the gas. When the valve assembly IV is closed, the adsorbent column tube can be sealed. The valve assembly IV preferably includes a pneumatic valve IV installed on the pipeline at the gas inlet end of the adsorbent column tube and a pneumatic valve V installed on the pipeline at the gas outlet end of the adsorbent column tube. Furthermore, the valve assembly IV also includes a pneumatic valve VI, which is installed on the pipeline between the pneumatic valve V and the adsorbent column tube.

[0016] In the above-mentioned device for measuring the adsorption amount of mixed gas of materials, in the actual production process, the gas to be adsorbed is usually unchanged, but in order to further enhance the scope of application of the device and ensure the accuracy of the adsorption test, the measuring device also preferably includes a vacuum unit, the vacuum unit includes a valve assembly VIII and a vacuum pump which are sequentially connected to the outlet end of the stop valve I through a pipeline, the valve assembly VIII includes a pneumatic valve VII, and the vacuum pump can be used to evacuate the entire pipeline of the device to remove impurity gases, thereby further improving the accuracy of the measurement.

[0017] In order to further enhance the overall safety and reliability of the device for measuring the adsorption amount of mixed gas of materials, the gas supply unit preferably also includes a valve assembly IX, which includes a pressure reducing valve II, a stop valve IV and a stop valve V. The pressure reducing valve II is connected between the needle valve II and the flow meter through a pipeline, and the stop valve IV and the stop valve V are respectively connected in parallel to the pipeline between the needle valve II and the stop valve I through pipelines. Valve assembly IX is designed as a safety redundancy. When the pipeline pressure exceeds the set safety pressure, the pressure reducing valve II can be opened to reduce the pressure, and / or the stop valve IV and the stop valve V can be opened to discharge the gas.

[0018] In the above-mentioned device for measuring the adsorption amount of mixed gas of a material, the valve assembly V is mainly used for on-off control of high-purity gas, and the valve assembly V preferably includes a stop valve VI installed on the connecting pipe between the high-purity gas bottle and the gas inlet end of the adsorbent column tube. Further, the high-purity gas should generally be the main component gas of the mixed gas to be tested, such as a mixed gas of neon, hydrogen, oxygen, nitrogen, etc. in helium, and the high-purity gas should be high-purity helium.

[0019] In the above-mentioned device for measuring the adsorption amount of material mixed gas, the valve component VI is mainly used for on-off control of the gas at the outlet of the adsorbent column tube, so that the gas at the outlet of the adsorbent column tube enters the buffer gas bottle or the detection unit through it, and the valve component VI preferably includes a stop valve VII and a stop valve VIII installed on the connecting pipe between the adsorbent column tube and the buffer gas bottle.

[0020] In the above-mentioned device for measuring the adsorption amount of mixed gas of materials, the buffer gas cylinder is an evacuated gas cylinder. In order to allow the desorbed gas to enter the buffer gas cylinder smoothly, the design principle of the volume size of the buffer gas cylinder is to make the gas pressure in the buffer gas cylinder smaller than the gas pressure of the left tube. On this basis, the volume size of the buffer gas can be set according to actual production needs. In general, the volume of the buffer gas cylinder is larger than the volume of the adsorbent column tube to meet the above requirements. The large difference between the volume of the buffer gas cylinder and the adsorbent column tube is used to achieve pressure drop, which is conducive to the desorption and transfer of the adsorbed gas. There is no special restriction on the number of buffer gas cylinders. In the present invention, the number of buffer gas cylinders is preferably two, including buffer gas cylinder I and buffer gas cylinder II. Among them, buffer gas cylinder I is the main storage gas cylinder. After the first adsorption, it can be reduced in pressure and continue to be sucked in the subsequent process. After reaching pressure balance, the buffer gas cylinder II is used to balance the residual pressure to achieve negative pressure suction, which promotes the rapid desorption and transfer of the adsorbed gas. By repeatedly filling with high-purity gas for dilution, and then reducing pressure and sucking under negative pressure, the adsorbed gas can be completely desorbed and completely transferred.

[0021] In the above-mentioned device for measuring the adsorption amount of mixed gas of a material, the main function of the chromatograph is to detect the concentration change of the impurity gas during the dynamic adsorption process to determine the adsorption saturation. Therefore, the chromatograph can also be directly connected to the gas outlet end of the adsorbent column tube through a pipeline, and the valve assembly VII is installed on the connecting pipeline between the chromatograph and the gas outlet end of the adsorbent column tube. The valve assembly VII preferably includes a needle valve III. In order to further improve the detection efficiency of the present device, in the present invention, the chromatograph is preferably connected to the connecting pipeline between the stop valve VII and the stop valve VIII through a pipeline, and the valve assembly VII is installed on the gas inlet end pipeline of the chromatograph. In this preferred embodiment, the chromatograph is not only connected to the adsorbent column tube, but also to the buffer gas bottle. When it is necessary to determine the adsorption saturation state, the mixed gas can be allowed to enter the chromatograph by opening the stop valve VII and the needle valve III. When it is necessary to detect the content of the impurity gas component in the buffer gas bottle, the stop valve VIII and the needle valve III can be opened for detection, so that the buffer gas bottle does not need to be separately connected to the chromatograph, which reduces the manpower operation cost and effectively improves the detection efficiency.

[0022] The above-mentioned device for measuring the adsorption amount of mixed gas of the material, in order to better detect the pressure and temperature in the pipeline, the device also preferably includes a pressure measuring component and a temperature measuring component. The pressure measuring component includes several pressure test gauges, and the temperature measuring component includes several temperature test gauges. The specific installation positions of the pressure test gauges and the temperature test gauges can be installed according to actual monitoring needs. Generally, at least one pressure test gauge can be set at the connection of each unit, and a pressure test gauge can be installed in each unit as appropriate depending on the specific situation. The temperature test gauge can be installed before and after the pre-cooling tube, the rewarming tube and the adsorbent column tube.

[0023] The present invention also provides a transfer weighing method for measuring the amount of gas adsorption by a material mixture, wherein the transfer weighing method uses the aforementioned device for measuring the amount of gas adsorption by a material mixture to perform a measurement, and comprises the following steps:

[0024] S11. Initial state adjustment: In the initial state, the flow rate and pressure of the mixed gas discharged from the raw gas cylinder are adjusted through each valve component until the flow rate and pressure are stable and reach the initial set pressure and initial set flow rate; the specific implementation method is: initially, all valve components are in a closed state, and valve component I, valve component II, and valve component III are opened in sequence, and the mixed gas provided by the raw gas cylinder is discharged through valve component I, valve component II, and valve component III in sequence, and the gas flow rate and pressure are adjusted through each valve component until the flow rate and pressure are stable and reach the initial set pressure and initial set flow rate;

[0025] S12, impurity purging: use the high-purity gas provided by the high-purity gas cylinder to purge the adsorbent column tube and the detection unit with impurities, and adjust the high-purity gas pressure in the pipeline to the initial set pressure through each valve assembly; the specific implementation method is: open the valve assembly V, valve assembly VI and valve assembly VII, the high-purity gas cylinder provides high-purity gas and is discharged through the valve assembly V, the adsorbent column tube, valve assembly VI and the detection unit to purge the impurities, and after the purge is completed, close the valve assembly VI and valve assembly VII, and adjust the gas pressure in the pipeline to the initial set pressure through each valve assembly;

[0026] S13, low temperature adsorption: cool the adsorbent column filled with adsorbent material to the gas adsorption temperature, and continue to add high-purity gas until the pressure is greater than the initial set pressure in step S11 and stabilizes, then close valve assembly V; at the same time, close valve assembly II and open valve assembly IV, the adsorbent column performs low temperature adsorption on the mixed gas at the gas adsorption temperature, open valve assembly VI and valve assembly VII to allow the gas at the outlet of the adsorbent column to enter the chromatograph, and use the chromatograph to detect the concentration change of the mixed gas components. When the chromatograph detects the mixed gas components of the set value, it is considered to have reached adsorption saturation, close valve assembly IV to seal the adsorbent column, open valve assembly II, and close valve assembly VI and valve assembly VII at the same time;

[0027] S14, negative pressure desorption: reheat the adsorbent column tube to the gas desorption temperature, open the valve assembly VI to allow the gas at the outlet of the adsorbent column tube to enter the buffer gas cylinder, perform gas desorption at the gas desorption temperature, and use the negative pressure of the buffer gas cylinder to transfer the desorbed gas and store it in the buffer gas cylinder. Several buffer gas cylinders (401) can be used alternately until the pressure of the last used buffer gas cylinder is balanced;

[0028] S15, dilution transfer: close valve assembly VI and open valve assembly V at the same time, use high-purity gas cylinder to provide high-purity gas to dilute the residual desorbed gas until the pressure of the adsorbent column tube is the set pressure; close valve assembly V and open valve assembly VI at the same time, and use the decompression or negative pressure suction of the buffer gas cylinder again to transfer and store the desorbed gas in the buffer gas cylinder to achieve pressure balance (when there are more than two buffer gas cylinders, each gas cylinder can be used alternately until the pressure of the last buffer gas cylinder used is balanced); then close valve assembly VI and open valve assembly V at the same time, repeat this step several times until the gas in the adsorbent column tube is consistent with the high-purity gas composition (indicating that the mixed gas in the adsorbent column tube has been completely desorbed at this time), and close valve assembly VI;

[0029] S16. Component measurement: Weigh the increase in the buffer gas cylinder to obtain the mass of the gas stored in the buffer gas cylinder, and then connect the buffer gas cylinder to the chromatograph in this device or an external chromatograph to measure the content of each component of the mixed gas, thereby calculating the adsorption amount of each component of the mixed gas and the volume under standard conditions.

[0030] The weighing and transfer method for measuring the adsorption amount of mixed gas is based on the following principle: when the adsorbent column and the cooling device (usually a liquid nitrogen cylinder) reach temperature equilibrium, a certain flow of mixed gas is introduced at a certain pressure, and at the same time, the concentration change of impurities in the high-purity gas is detected at the outlet of the adsorbent column. When a certain value of a certain impurity component is detected at the outlet, it is considered to be adsorbed saturated, and then the adsorbed impurity gas is completely desorbed and transferred to the buffer gas bottle with high-purity gas. The mass of the impurity component and the volume under standard conditions are calculated by weighing the mass of the mixed gas and determining the content of the impurity component in the gas. Obviously, part of the mixed gas can also be released from the buffer gas bottle to measure its volume, weigh its mass, and thus calculate the volume of the impurity component.

[0031] In the above transfer volume determination method for pure gas adsorption measurement, the initial set pressure and initial set flow rate in steps S11-S16 can be set with reference to the flow rate and pressure values ​​used in conventional gas adsorption operations in the art, and the present invention has no special limitations on this.

[0032] In the above transfer volume determination method for mixed gas adsorption, in step S12, the cooling method for cooling the adsorbent column tube to the gas adsorption temperature can adopt conventional cooling methods in the art. Usually, the low temperature of the gas adsorption temperature refers to the liquid nitrogen temperature. A liquid nitrogen barrel is placed on the adsorbent column tube to cool the adsorbent column tube in a liquid nitrogen bath until the temperature is balanced.

[0033] In the above transfer volume determination method for mixed gas adsorption determination, in step S13, the purpose of continuously replenishing high-purity gas until the gas pressure in the adsorbent column is greater than the initial set pressure in step S11 is to prevent the mixed gas outside the adsorbent column from instantly penetrating the adsorbent layer when entering the adsorbent column when the pneumatic valve IV and the gas valve V are opened, so that the chromatographic detection cannot obtain an accurate adsorption saturation time and causes a misjudgment. On the premise of achieving the aforementioned purpose, the specific value of the gas pressure in the adsorbent column is not particularly limited, and is usually slightly greater than the initial set pressure in step S11. Furthermore, there are usually main gas components and impurity gas components in the mixed gas, and here the main purpose is to detect the change in the concentration of the impurity gas component. When the chromatograph detects a set value of the mixed gas component, it is considered to have reached adsorption saturation. The set value here is also not particularly limited, and those skilled in the art can make corresponding determinations based on the specific impurity gas.

[0034] In the above transfer volume determination method for mixed gas adsorption, in step S14, the heating method for reheating the adsorbent column to the gas desorption temperature can be a conventional heating method in the art, and there is no special requirement. In the present invention, after the liquid nitrogen barrel is removed, the adsorbent column is heated by a water bath and a heating furnace until the gas desorption temperature is reached. The gas desorption temperature is usually heated to 100°C, and the temperature of the adsorbent filled in the adsorbent column is at least 80°C.

[0035] In the above transfer volume determination method for mixed gas adsorption, in step S15, the inventors have tested and proved that after repeatedly using the high-purity gas cylinder to provide high-purity gas to dilute the residual desorbed gas and desorb 10 times or more, the gas in the adsorbent column is consistent with the high-purity gas composition. Therefore, it is preferred to repeat the dilution and transfer operation in step S15 10 times or more to achieve complete transfer of the desorbed gas.

[0036] In the above transfer volume determination method for mixed gas adsorption determination, in step S16, the calculation method of the adsorption amount of each component of the mixed gas and the volume under standard conditions is known to those skilled in the art. The specific calculation method is as follows:

[0037] The mass of each component in the mixed gas is calculated using formula (1):

[0038] m i =m 混合气 ×y i (1)

[0039] In the formula, m i is the mass of component i (g), m 混合气 is the total mass of the mixed gas (g), y i is the concentration of component i in the mixed gas (g / g).

[0040] The volume of gas under standard conditions is calculated using formula (2):

[0041] V i =V i标 ×m i / M i ……(2)

[0042] Where m i is the mass of component i (g), M i is the molar mass of component i (g), V i is the volume of component i gas under standard conditions (ml), V i标 is the molar volume of component i gas under standard conditions (ml / mol).

[0043] At normal temperature and pressure, the volume measurement method can be used to measure the volume of part of the mixed gas. The volume of each component gas in the mixed gas is calculated according to formula (3), and then converted into the volume under standard conditions.

[0044]

[0045] Where V i is the volume of impurity component i (ml), V 混合气放 is the volume of the mixed gas put into the volume measuring device from the gas cylinder (ml), m 混合气总 is the total mass of the mixed gas in the cylinder (g), m 混合气放 is the mass of the mixed gas put into the volume measuring device from the gas cylinder (g), X i is the concentration of component i in the mixed gas (V / V).

[0046] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0047] (1) The device for measuring the adsorption amount of mixed gas provided by the present invention uses a gas supply unit to provide mixed gas. After the adsorption equilibrium of the adsorbent column tube is reached, the adsorbent column tube is sealed, and the gas adsorbed on the adsorbent is desorbed. The adsorbed gas is transferred to a buffer gas bottle by decompression or negative pressure suction, and is quantitatively measured by weighing and chromatographic analysis. This avoids the errors caused by factors such as sensor accuracy, installation accuracy, spring scale accuracy, gas buoyancy and temperature difference in the in-situ measurement of the prior art, greatly reduces the accuracy requirements for measuring instruments, realizes the complete transfer and accurate measurement of the adsorbed gas, and solves the problem of accurate measurement of the adsorption amount of multi-component mixed gases. The weighing method is an internationally recognized method. Weighing after transfer effectively avoids the influence of gas buoyancy and temperature difference on the symmetry. At the same time, weighing after the gas volume is increased greatly reduces the accuracy requirements for the balance.

[0048] (2) The device provided by the present invention is used to measure the amount of gas adsorption of a material mixture. The factors affecting the gas adsorption amount are usually pressure, temperature and flow rate. The device can adjust the initial gas pressure and initial gas flow rate through valve component I, valve component II and valve component III, thereby meeting the dynamic adsorption test requirements of the gas at low temperature (usually liquid nitrogen temperature) and different pressures (0.03-16MPa).

[0049] (3) The transfer weighing method for measuring the adsorption amount of mixed gas in materials provided by the present invention is based on the aforementioned measuring device, and realizes low-temperature and high-pressure steady-flow adsorption, temperature increase and pressure reduction desorption, transfer measurement and rapid switching and purge replacement, avoiding the errors caused by factors such as sensor accuracy, installation accuracy, spring scale accuracy, gas buoyancy and temperature difference in the in-situ measurement of the prior art, greatly reducing the accuracy requirements of the measuring instrument, realizing the complete transfer and accurate measurement of the adsorbed gas, the experimental steps are simple, easy to operate, and has strong practicality and good application prospects, and is worthy of promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 The present invention is a schematic diagram of the gas flow of a device for measuring the adsorption amount of mixed gas of a material.

[0051] Description of reference numerals: 1. gas supply unit; 101. raw gas cylinder; 102. pressure reducing valve I; 103. needle valve I; 104. pneumatic valve I; 105. pneumatic valve II; 106. pneumatic valve III; 107. needle valve II; 108. stop valve I; 109. stop valve II; 110. flow meter; 111. stop valve III; 112. pressure reducing valve II; 113. stop valve IV; 114. stop valve V; 115. precooling pipe; 116. reheating pipe ; 2. Adsorption unit; 201. Adsorbent column tube; 202. Pneumatic valve IV; 203. Pneumatic valve V; 204. Pneumatic valve VI; 3. Pure gas unit; 301. High-purity gas cylinder; 302. Shut-off valve VI; 4. Desorption gas buffer unit; 401. Buffer gas cylinder; 402. Shut-off valve VII; 403; Shut-off valve VIII; 5. Detection unit; 501. Chromatograph; 502. Needle valve III; 6. Vacuum unit; 601. Vacuum pump; 602. Pneumatic valve VII. DETAILED DESCRIPTION

[0052] The technical solutions of the embodiments of the present invention are clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the present invention.

[0053] Example 1

[0054] The device for measuring the adsorption amount of mixed gas provided in this embodiment is as follows: Figure 1 As shown, it includes a gas supply unit 1 and an adsorption unit 2 which are sequentially connected through pipelines, and a pure gas unit 3, a desorption gas buffer unit 4, and a detection unit 5 which are respectively connected to the adsorption unit 2 through pipelines, and also includes a pressure measuring component and a temperature measuring component.

[0055] The gas supply unit 1 includes a raw gas cylinder 101 and a valve assembly I, a valve assembly II and a valve assembly III connected to the raw gas cylinder 101 in sequence through a pipeline. The raw gas cylinder 101 is used to provide a mixed gas which is discharged after adjusting the flow and pressure through the valve assembly I, the valve assembly II and the valve assembly III in sequence. The valve assembly I includes a pressure reducing valve I 102, a needle valve I 103 and a pneumatic valve I 104 which are installed in sequence on the connecting pipeline between the raw gas cylinder 101 and the adsorption unit 2. The valve assembly II includes a pneumatic valve II 105. The valve assembly III includes a pneumatic valve III 106, a needle valve II 107, a stop valve I 108, a stop valve II 109, a flow meter 110 and a stop valve III 111 which are connected in sequence through a pipeline. The mixed gas flows through the pressure reducing valve I102, needle valve I103, pneumatic valve I104 and adsorption unit 2 in sequence or directly through the pneumatic valve II105, and then flows through the pneumatic valve III106, needle valve II107, stop valve I108, stop valve II109, flow meter 110 and stop valve III111 in sequence before being discharged. The pressure reducing valve I102 adjusts the pressure of the mixed gas to reach the set adsorption pressure. The needle valve I103 and the needle valve II107 adjust the flow rate of the raw gas.

[0056] In order to further enhance the safety and reliability of the device for measuring the adsorption amount of mixed gas of materials provided in this embodiment, a safety redundant component is further added in the measuring device. Specifically, the gas supply unit 1 also includes a valve component IX, which includes a pressure reducing valve II 112, a stop valve IV 113 and a stop valve V 114. The pressure reducing valve II 112 is connected between the needle valve II 107 and the flow meter 110 through a pipeline, and the stop valve IV 113 and the stop valve V 114 are respectively connected in parallel to the pipeline between the needle valve II 107 and the stop valve I 108 through pipelines.

[0057] In order to pre-cool the raw gas before entering the adsorption unit 2 when production requires, a pre-cooling pipe 115 is wound around the connecting pipe between the pneumatic valve I 104 and the air inlet end of the adsorption unit 2. In order to reduce the requirements for valve performance, in this embodiment, a heat recovery pipe 116 is also wound around the pipe between the pneumatic valve III 106 and the needle valve II 107.

[0058] The adsorption unit 2 includes an adsorbent column tube 201 and a valve assembly IV. The two ends of the adsorbent column tube 201 are connected to the gas outlet end of the valve assembly I and the gas outlet end of the valve assembly II through pipelines. The adsorbent column tube 201 is filled with an adsorbent for adsorbing gas, such as activated carbon, molecular sieves, silica gel, activated aluminum and other common adsorbents in the field. In this embodiment, a DN15Ф21*3, 400mm long pipeline is used as the adsorbent column tube 201, and activated carbon is filled inside as an adsorbent. The valve assembly IV includes a pneumatic valve IV202, a pneumatic valve V203 and a pneumatic valve VI204. The pneumatic valve IV 202 is installed on the connecting pipe between the air inlet end of the adsorbent column tube 201 and the pneumatic valve I 104, the pneumatic valve V 203 is installed on the connecting pipe between the air outlet end of the adsorbent column tube 201 and the pneumatic valve III 106, and the pneumatic valve VI 204 is installed between the pneumatic valve V 203 and the adsorbent column tube 201. When the adsorption is saturated, the adsorbent column tube 201 can be sealed by closing the pneumatic valve IV 202 and the pneumatic valve V 203 at the same time.

[0059] The pure gas unit 3 includes a valve assembly V and a high-purity gas cylinder 301 connected in sequence to the gas inlet end of the adsorbent column tube 201 through a pipeline. The valve assembly V includes a stop valve VI 302 installed on the connecting pipeline between the high-purity gas cylinder 301 and the gas inlet end of the adsorbent column tube 201. The high-purity gas cylinder 301 is used to provide high-purity gas. The high-purity gas enters the adsorbent column tube 201 through the stop valve VI 302. The high-purity gas is the main component gas of the mixed gas to be tested, such as a mixed gas of neon, hydrogen, oxygen, nitrogen, etc. in helium, and the high-purity gas should be high-purity helium.

[0060] The desorbed gas buffer unit 4 includes a valve assembly VI and a buffer gas bottle 401 which are sequentially connected to the gas outlet end of the adsorbent column tube 201 through a pipeline. The outlet gas of the adsorbent column tube 201 enters the buffer gas bottle 401 or the detection unit 5 through the valve assembly VI. There are two buffer gas bottles 401, namely, buffer gas bottle I and buffer gas bottle II. The valve assembly VI includes a stop valve VII 402 and a stop valve VIII 403 installed on the connecting pipe between the adsorbent column tube 201 and the buffer gas bottle 401. The adsorbent column tube 201 performs gas desorption at the gas desorption temperature. Under the action of the reduced pressure or negative pressure of the buffer gas bottle 401, the desorbed gas is transferred and stored in the buffer gas bottle 401 through the stop valve VII 402 and the stop valve VIII 403.

[0061] The detection unit 5 includes a chromatograph 501 and a valve assembly VII. The chromatograph 501 is connected to the connecting pipeline between the stop valve VII 402 and the stop valve VIII 403 through a pipeline, and the valve assembly VII includes a needle valve III 502 installed on the pipeline at the gas inlet end of the chromatograph 501. The chromatograph 501 is used to detect whether the adsorption of the adsorbent column tube 201 is saturated and to measure the content of the mixed gas components in the buffer gas bottle 401.

[0062] The pressure measuring assembly includes four pressure test gauges, namely pressure test gauge P1, pressure test gauge P2, pressure test gauge P3, and pressure test gauge P4. Pressure test gauge P1 is installed on the pipeline between the stop valve VI302 and the adsorbent column tube 201. Pressure test gauge P2 is installed on the pipeline at the outlet end of the pneumatic valve VI204. Pressure test gauge P3 is installed on the pipeline at the outlet end of the stop valve V114. Pressure test gauge P4 is installed on the pipeline at the outlet end of the pneumatic valve V203. In this embodiment, the pressure accuracy of the pressure test gauge P2 is high and the measurement range (0-4MPa) is small. The pneumatic valve VI204 is mainly used to connect or shut off the pressure test gauge P2 to prevent the pressure test gauge P2 from being damaged by overpressure. There is a pressure test gauge P1 (pressure measurement range (0-20MPa) between the adsorbent column tube and the pneumatic valve II. When the pressure is higher than 4MPa, the gas pressure can be measured by the pressure test gauge P1.

[0063] The temperature measuring assembly includes two temperature test gauges, namely temperature test gauge T1 and temperature test gauge T2. Temperature test gauge T1 is installed on the pipeline at the air inlet end of stop valve VII402. Temperature test gauge T2 is installed on the pipeline at the air outlet end of pressure reducing valve II112 and stop valve II109.

[0064] In this embodiment, in order to further enhance the testing accuracy of the device, the measuring device also includes a vacuum unit 6 connected to the air supply unit 1, the vacuum unit 6 includes a valve assembly VIII and a vacuum pump 601 which are sequentially connected to the outlet end of the stop valve I108 through a pipeline, the valve assembly VIII includes a pneumatic valve VII 602, and the vacuum pump 601 is used to evacuate the pipeline.

[0065] Example 2

[0066] The transfer weighing method for measuring the mixed gas adsorption amount of a material provided in this embodiment uses the adsorption measurement device provided in Example 1 to measure the mixed gas adsorption amount, and specifically includes the following steps:

[0067] S11. Initial state adjustment: In the initial state, all valve components are closed. Open pressure reducing valve Ⅰ102, needle valve Ⅰ103, pneumatic valve Ⅰ104, pneumatic valve Ⅱ105, pneumatic valve Ⅲ106, needle valve Ⅱ107, stop valve Ⅰ108, stop valve Ⅱ109 and stop valve Ⅲ111 in sequence. The mixed gas provided by raw gas cylinder 101 is discharged through pressure reducing valve Ⅰ102, needle valve Ⅰ103, pneumatic valve Ⅰ104, pneumatic valve Ⅱ105, pneumatic valve Ⅲ106, needle valve Ⅱ107, stop valve Ⅰ108, stop valve Ⅱ109, flow meter 110 and stop valve Ⅲ111 in sequence. Adjust the gas flow and pressure through each valve until the initial set flow reaches and stabilizes at 10l / min, and the initial set pressure stabilizes at 15MPa.

[0068] S12, impurity purging: open the stop valve VI302, the stop valve VII402 and the needle valve III502, the high-purity gas cylinder 301 provides high-purity gas and discharges it through the stop valve VI302, the adsorbent column tube 201, the stop valve VII402, the needle valve III502 and the chromatograph 501 to purge the impurities. After the purge is completed, close the stop valve VII402 and the needle valve III502, and adjust the high-purity gas pressure in the pipeline to 15 MPa;

[0069] S13, low temperature adsorption: put the liquid nitrogen barrel on the adsorbent column tube 201 so that the adsorbent column tube 201 is placed in the liquid nitrogen bath and reaches temperature equilibrium, and continuously add high-purity gas until the pressure is 15.2MPa, that is, slightly higher than the pressure outside the adsorbent column tube, to prevent the mixed gas outside the adsorbent column tube from returning to the outlet end. The pressure is stable for 1 to 2 minutes, and the stop valve VI 302 is closed; the pneumatic valve II 105 is closed and the pneumatic valve IV 202 and the pneumatic valve V 203 are opened. The adsorbent column tube 201 performs low-temperature adsorption on the mixed gas at the gas adsorption temperature, and the stop valve VII 402 and the needle valve III 502 are opened. The concentration change of the mixed gas components is detected by the chromatograph 501. When the chromatograph 501 detects the mixed gas components of the set value, it is considered to have reached adsorption saturation (for example, helium is used as the high-purity gas and hydrogen in helium is used as the mixed gas, and the hydrogen reaches 3×10 -6 V / V can be regarded as saturated), close the pneumatic valve IV202 and the pneumatic valve V203 to seal the adsorbent column tube 201, and at the same time close the stop valve VII402 and the needle valve III502, and open the pneumatic valve II105, and close the valve of the raw gas cylinder 101;

[0070] S14, negative pressure desorption: placing the adsorbent column tube 201 in a hot water bath and continuously heating it with a heating furnace, heating to 100°C, the temperature of the activated carbon in the adsorber reaches at least 80°C, opening the stop valve VII 402 and the stop valve VIII 403, performing gas desorption at the gas desorption temperature, using the negative pressure of the buffer gas cylinder I to transfer part of the desorbed gas and store it in the buffer gas cylinder I, wait for the pressure of the buffer gas cylinder I to be balanced, open the buffer gas cylinder II, use the buffer gas cylinder II to balance the residual pressure, realize negative pressure suction, and transfer part of the desorbed gas again and store it in the buffer gas cylinder II until the pressure of the buffer gas cylinder II is balanced;

[0071] S15: Dilution transfer: close the stop valve VII 402, and open the stop valve VI 302 at the same time, use the high-purity gas cylinder 301 to provide high-purity gas to dilute the residual impurity gas in the pipeline, and fill the high-purity gas until the pressure of the adsorbent column tube 201 is 0.5MPa; close the stop valve VI 302, and open the stop valve VII 402 at the same time, open the buffer gas I, decompress and extract the gas and store it in the buffer gas cylinder I until the pressure of the buffer gas cylinder I is balanced, close the valve of the buffer gas cylinder I, open the buffer gas cylinder I, and use the buffer gas cylinder Ⅱ balances the residual pressure to achieve negative pressure suction, and transfers part of the desorbed gas again and stores it in the buffer gas bottle Ⅱ until the pressure of the buffer gas bottle Ⅱ is balanced, and closes the valve of the buffer gas bottle Ⅱ; then closes the valve assembly VI, and opens the valve assembly V at the same time, and repeats this step 10 times (tests have proved that after repeating 10 times, the gas in the adsorbent column tube 201 is consistent with the raw material high-purity gas composition after testing); fills with high-purity gas for dilution and transfers the desorbed gas until the final pressure of the buffer gas bottle Ⅱ is 0.4MPa, and closes the bottle valve;

[0072] S16. Component measurement: weigh the increase in buffer gas cylinder Ⅰ and buffer gas cylinder Ⅱ to obtain the mass of the desorbed gas stored in buffer gas cylinder Ⅰ / Ⅱ, open the stop valve Ⅷ403 and the needle valve Ⅲ502, and allow the gas in buffer gas cylinder Ⅰ / Ⅱ to enter the chromatograph 501. The chromatograph 501 measures the content of impurity components in the gas, thereby calculating the mass of the impurity gas and the volume under standard conditions.

[0073] In step S16, the specific calculation method of the adsorption amount of each component of the mixed gas and the volume under the standard state is as follows:

[0074] The mass of each component in the mixed gas is calculated using formula (1):

[0075] m i =m 混合气 ×y i (1)

[0076] In the formula, m i is the mass of component i (g), m 混合气 is the total mass of the mixed gas (g), y i is the concentration of component i in the mixed gas (g / g).

[0077] The volume of gas under standard conditions is calculated using formula (2):

[0078] V i =V i标 ×m i / M i ……(2)

[0079] Where m i is the mass of component i (g), M iis the molar mass of component i (g), V i is the volume of component i gas under standard conditions (ml), V i标 is the molar volume of component i gas under standard conditions (ml / mol).

[0080] At normal temperature and pressure, the volume measurement method can be used to measure the volume of part of the mixed gas. The volume of each component gas in the mixed gas is calculated according to formula (3), and then converted into the volume under standard conditions.

[0081]

[0082] Where V i is the volume of impurity component i (ml), V 混合气放 is the volume of the mixed gas put into the volume measuring device from the gas cylinder (ml), m 混合气总 is the total mass of the mixed gas in the cylinder (g), m 混合气放 is the mass of the mixed gas put into the volume measuring device from the gas cylinder (g), X i is the concentration of component i in the mixed gas (V / V).

[0083] Example 3

[0084] In this embodiment, the device for measuring the adsorption amount of mixed gas of a material provided in Example 1 and the transfer weighing method provided in Example 2 are used, and mixed gases of argon in helium, nitrogen in helium and oxygen in helium are introduced as test gases to carry out repeatability experiments. The repeatability test results are shown in Table 1.

[0085] Table 1 Repeatability test results of transfer weighing method

[0086]

[0087] The total relative uncertainty of the measurement results of the transfer weighing method is:

[0088] Uncertainty of gas mass weighing: The minimum weighing mass is 5.300g, the uncertainty is 0.0104g, the relative standard uncertainty is 0.196%, and the relative uncertainty of the two mass weighings is 0.392%.

[0089] Uncertainty of component content measurement: the relative uncertainty of the standard gas is 1%, the relative standard deviation of the repeatability of the chromatographic analysis is 1%, and the uncertainty of the component content measurement is 1.74%.

[0090] The relative standard uncertainty determined by the transfer weighing method was 1.78%, and the total relative uncertainty was 3.6%.

[0091] Combined with Table 1, it can be seen that the maximum relative standard deviation of the 6 repeated measurement results of the transfer weighing method is 1.26, and the total relative uncertainty is 3.6%, indicating that the measurement results of the transfer weighing method are accurate and reliable.

[0092] Example 4

[0093] In this embodiment, the device for measuring the adsorption amount of the material mixed gas provided in Example 1 and the transfer weighing method provided in Example 2 are used, and the carbon monoxide mixed gas in helium, the neon, hydrogen, oxygen, nitrogen and methane mixed gas in helium are used as raw gas, and helium is used as high-purity gas. Experiments are carried out to obtain the adsorption amount of the mixed gas and the volume under standard conditions. In addition, a volume meter is used to measure the volume of the released part of the mixed gas and convert it into the volume under standard conditions, so as to verify the accuracy of the transfer weighing method. The test results are shown in Table 2.

[0094] Table 2 Comparison results of gas measurement volume and weighing calculated volume

[0095]

[0096]

[0097] It can be seen from Table 2 that for the transfer weighing method, the maximum relative deviation between the calculated result and the actual measured result is 3.0%, which is less than 5%, proving that the measurement result of the transfer weighing method is accurate.

[0098] Those skilled in the art will appreciate that the embodiments herein are intended to help readers understand the principles of the present invention, and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations that do not deviate from the essence of the present invention based on the technical revelations disclosed by the present invention, and these variations and combinations are still within the protection scope of the present invention.

Claims

1. A device for measuring the amount of mixed gas adsorbed by a material, characterized in that: It comprises a gas supply unit (1) and an adsorption unit (2) which are sequentially connected via pipelines, and also comprises a pure gas unit (3), a desorbed gas buffer unit (4) and a detection unit (5) which are respectively connected to the adsorption unit (2) via pipelines; The gas supply unit (1) comprises a raw gas cylinder (101) for providing mixed gas, and a valve assembly I, a valve assembly II and a valve assembly III which are sequentially connected to the raw gas cylinder (101) via a pipeline; The adsorption unit (2) comprises an adsorbent column tube (201) whose two ends are respectively connected to the gas outlet end of the valve component I and the gas outlet end of the valve component II through pipelines, and a valve component IV, wherein the valve component IV comprises pipelines installed on the gas inlet end and the gas outlet end of the adsorbent column tube (201) to seal the adsorbent column tube (201) when the adsorption is saturated; the mixed gas can enter the adsorption unit (2) through the valve component I and then be discharged through the valve component III; The pure gas unit (3) comprises a valve component V and a high-purity gas cylinder (301) which are sequentially connected to the gas inlet end of the adsorbent column tube (201) through a pipeline, and the high-purity gas cylinder (301) is used to provide high-purity gas, and the high-purity gas enters the adsorption unit (2) through the valve component V; The desorbed gas buffer unit (4) comprises a valve assembly VI and one or more buffer gas bottles (401) which are sequentially connected to the gas outlet end of the adsorbent column tube (201) through a pipeline; the adsorbent column tube (201) performs gas desorption at a gas desorption temperature, and under the suction effect of reduced pressure or negative pressure of the buffer gas bottle (401), the desorbed gas is transferred through the valve assembly VI and stored in the buffer gas bottle (401); The detection unit (5) comprises a valve assembly VII and a chromatograph (501) which are sequentially connected to the valve assembly VI via a pipeline; the outlet gas of the adsorbent column tube (201) enters the buffer gas bottle (401) or the detection unit (5) via the valve assembly VI; the chromatograph (501) is used to detect whether the adsorption of the adsorbent column tube (201) is saturated and to measure the content of the mixed gas components in the buffer gas bottle (401).

2. The device for measuring the amount of mixed gas adsorption by a material according to claim 1, characterized in that: It also includes a precooling pipe (115), which is arranged around the connecting pipe between the valve assembly I and the adsorption unit (2).

3. The device for measuring the amount of mixed gas adsorption by a material according to claim 1, characterized in that: The valve assembly I comprises a pressure reducing valve I (102), a needle valve I (103) and a pneumatic valve I (104) which are sequentially installed on the connecting pipe between the raw gas bottle (101) and the adsorbent column tube (201); the valve assembly II comprises a pneumatic valve II (105).

4. The device for measuring the amount of mixed gas adsorption by a material according to claim 1, characterized in that: The valve assembly III comprises a pneumatic valve III (106), a needle valve II (107), a stop valve I (108), a stop valve II (109), a flow meter (110) and a stop valve III (111) which are sequentially connected via a pipeline; and further comprises a heat recovery pipe (116) which is arranged around the pipeline between the pneumatic valve III (106) and the needle valve II (107).

5. The device for measuring the adsorption amount of mixed gas of a material according to claim 1, characterized in that: The valve assembly IV comprises a pneumatic valve IV (202) installed on the pipeline at the air inlet end of the adsorbent column tube (201) and a pneumatic valve V (203) installed on the pipeline at the air outlet end of the adsorbent column tube (201).

6. The device for measuring the adsorption amount of mixed gas of a material according to claim 1, characterized in that: It also includes a vacuum unit (6), which includes a valve assembly VIII and a vacuum pump (601) which are sequentially connected to the gas outlet end of the stop valve I (108) through a pipeline, and the valve assembly VIII includes a pneumatic valve VII (602). The vacuum pump (601) is used to evacuate the pipeline.

7. The device for measuring the amount of mixed gas adsorption by a material according to claim 1, characterized in that: The air supply unit (1) further comprises a valve assembly IX, which comprises a pressure reducing valve II (112), a stop valve IV (113) and a stop valve V (114), wherein the pressure reducing valve II (112) is connected between the needle valve II (107) and the flow meter (110) via a pipeline, and the stop valve IV (113) and the stop valve V (114) are respectively connected in parallel to the pipeline between the needle valve II (107) and the stop valve I (108) via pipelines.

8. The device for measuring the amount of mixed gas adsorption by a material according to claim 1, characterized in that: The valve assembly V comprises a stop valve VI (302) installed on the connecting pipe between the high-purity gas cylinder (301) and the gas inlet end of the adsorbent column tube (201); the valve assembly VI comprises a stop valve VII (402) and a stop valve VIII (403) installed on the connecting pipe between the adsorbent column tube (201) and the buffer gas cylinder (401).

9. The device for measuring the amount of mixed gas adsorption by a material according to claim 8, characterized in that: The chromatograph (501) is connected to the connecting pipeline between the stop valve VII (402) and the stop valve VIII (403) through a pipeline, and the valve assembly VII includes a needle valve III (502) installed on the pipeline at the air inlet end of the chromatograph (501).

10. A transfer weighing method for measuring the amount of mixed gas adsorption by a material, characterized in that: The device for measuring the adsorption amount of mixed gas of a material according to any one of claims 1 to 9 is used for determination, comprising the following steps: S11, initial state adjustment: In the initial state, the flow rate and pressure of the mixed gas discharged from the raw gas cylinder are adjusted through each valve assembly until the flow rate and pressure are stable and reach the initial set pressure and initial set flow rate; S12, impurity purging: using the high-purity gas provided by the high-purity gas cylinder (301) to purge the adsorbent column tube (201) and the detection unit (5) of impurities, and adjusting the high-purity gas pressure in the pipeline to the initial set pressure through each valve assembly; S13, low temperature adsorption: the adsorbent column tube (201) containing the adsorbent material is cooled to the gas adsorption temperature, and high purity gas is continuously added until the pressure is greater than the initial set pressure in step S11 and stabilized, and then the valve component V is closed; at the same time, the valve component II is closed and the valve component IV is opened, and the adsorbent column tube (201) performs low temperature adsorption on the mixed gas at the gas adsorption temperature, and the valve components VI and VII are opened to allow the gas at the outlet of the adsorbent column tube (201) to enter the chromatograph (501), and the chromatograph (501) is used to detect the concentration change of the mixed gas components. When the chromatograph (501) detects the mixed gas components of the set value, it is considered that the adsorption is saturated, and the valve component IV is closed to seal the adsorbent column tube (201), and the valve component II is opened, and the valve components VI and VII are closed at the same time, and the valve component I and the raw gas cylinder are closed; S14, negative pressure desorption: the adsorbent column tube (201) is reheated to the gas desorption temperature, the valve assembly VI is opened to allow the gas at the outlet of the adsorbent column tube (201) to enter the buffer gas cylinder (401), the gas is desorbed at the gas desorption temperature, and the desorbed gas is transferred and stored in the buffer gas cylinder (401) by using the negative pressure of the buffer gas cylinder (401). Several buffer gas cylinders (401) can be used alternately until the pressure of the buffer gas cylinder (401) used last is balanced; S15: dilution transfer: close valve assembly VI and open valve assembly V at the same time, use the high-purity gas cylinder (301) to provide high-purity gas to dilute the residual desorbed gas until the pressure of the adsorbent column tube (201) reaches the set pressure; close valve assembly V and open valve assembly VI at the same time, use the buffer gas cylinder (401) to reduce pressure or negative pressure suction again, transfer the desorbed gas and store it in the buffer gas cylinder (401) to achieve pressure balance; then close valve assembly VI and open valve assembly V at the same time, repeat this step several times until the gas in the adsorbent column tube (201) is consistent with the high-purity gas composition, and close valve assembly VI; S16. Component measurement: weigh the increase in the buffer gas cylinder (401) to obtain the mass of the gas stored in the buffer gas cylinder (401), and then connect the buffer gas cylinder (401) to the chromatograph (501) to determine the content of each component of the mixed gas, thereby calculating the adsorption amount of each component of the mixed gas and the volume under standard state.

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