Plate type membrane differential pressure method gas permeability performance test equipment and process

Abstract

The application provides a plate type membrane differential pressure method gas permeability test device and process, the test device comprises a membrane cell, a vacuum control system, a computer control system, a raw material gas inlet system on the membrane, a purge gas inlet system under the membrane, a temperature control system, a flow and composition test system. The plate type membrane differential pressure method gas permeability test device provided by the application has high integration and environmental control function, and can be used for in-situ measurement under constant temperature or variable temperature conditions. After the plate type membrane is placed in the membrane cell and sealed through a gasket and a pressing plate in the test process, the constant pressure variable volume method or the constant volume variable pressure method can be used for plate type membrane material permeability test, so that the permeability of the plate type membrane and the intrinsic gas permeability of the material of the plate type membrane are obtained. Similarly, according to the structure characteristics of the plate type membrane, the device can be used for measuring the gas permeability and air permeability of various gas separation membranes, packaging materials and clothing fabrics.

Description

Technical Field

[0001] This invention relates to the field of instrumental analysis technology, and in particular to a plate membrane differential pressure method for testing gas permeability performance. Background Technology

[0002] Membrane separation technology, as a highly efficient, energy-saving, and environmentally friendly separation method, plays a significant role in various fields such as energy conservation, industrial production, aerospace, healthcare, and home life. In response to my country's ambitious "dual-carbon" goals, gas separation membrane materials related to carbon dioxide have received even greater attention. However, the construction of equipment for measuring and analyzing gas separation performance is fundamental to the research of membrane separation technology. Furthermore, different application scenarios require different measurement methods, and differential pressure gas permeation performance testing equipment with multiple testing methods is in high demand in the field of permeation measurement.

[0003] Currently, most commercially available equipment is based on constant-volume variable-volume methods (such as the vacuum pressure rise method), primarily designed for standardized testing of packaging material permeability. It calculates permeation parameters by monitoring the pressure increase rate in the confined space downstream of the membrane. However, this method has significant limitations when simulating real membrane separation processes (such as continuous flow unit operations like syngas separation and biogas purification), as its static cumulative testing mode differs considerably from dynamic industrial processes. In contrast, constant-pressure variable-volume methods (such as the purging method) can maintain a constant low pressure (atmospheric or near-atmospheric pressure) downstream of the membrane, directly and continuously measuring permeation flux using a high-precision gas flow meter, thus better reflecting membrane performance under stable operating conditions. Unfortunately, existing equipment often has limited functionality, making it difficult to integrate these two core methods on a single platform and achieve rapid switching, increasing the complexity of research comparisons and equipment costs. Furthermore, most existing equipment is limited to room temperature testing, while actual industrial separation processes often occur in variable-temperature environments. Temperature not only directly affects the gas permeation rate and selectivity but is also a key variable for studying the long-term thermal stability, plasticizing effect, and evaluating the durability of membrane materials under real-world conditions. The lack of in-situ temperature variation testing capabilities severely restricts the development of membrane materials from the laboratory to engineering applications.

[0004] Therefore, in response to a series of problems that exist in existing equipment, such as limited functionality, inconvenient switching of testing methods, and lack of in-situ temperature variation testing capabilities, it is of great scientific research and engineering application value to develop a plate membrane differential pressure gas permeation performance testing system that can integrate multiple measurement modes, support flexible switching, and has temperature control functions. Summary of the Invention

[0005] In view of the problems existing in the prior art, the present invention provides a plate membrane differential pressure method gas permeation performance testing device and process, which overcomes the shortcomings of existing devices such as not integrating multiple measurement methods in the same device, not being convenient to switch measurement methods, and not being in-situ measurement.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a plate-type membrane differential pressure method gas permeation performance testing device, the testing device comprising a membrane tank, a vacuum control system, a computer control system, a feed gas inlet system above the membrane, a purge gas inlet system below the membrane, a temperature control system, and a flow rate and composition testing system;

[0008] The vacuum control system includes an on-membrane vacuum control system and a below-membrane vacuum control system;

[0009] The temperature control system includes a constant temperature chamber, and the membrane tank is placed in the constant temperature chamber;

[0010] The flow rate and composition testing system includes a flow rate testing system and a chromatographic detection system.

[0011] A raw material gas inlet is provided above the membrane tank. The raw material gas inlet is connected to an air inlet pipe, which is divided into two branches: one branch is connected to the raw material gas inlet system on the membrane, and the other branch is connected to the vacuum control system on the membrane.

[0012] A purge gas inlet is provided below the membrane tank, and the purge gas inlet is connected to an air inlet pipe, which is connected to the under-membrane purge gas inlet system.

[0013] An exhaust port is provided below the membrane tank, and the exhaust port is connected to an exhaust pipe. The exhaust pipe is divided into two branches, one of which is connected to the flow test system and the other of which is connected to the chromatography detection system.

[0014] As a preferred technical solution of the present invention, the membrane pool includes a cap, a membrane pressure plate, a gas permeation membrane material and a metal mesh arranged sequentially from top to bottom.

[0015] Preferably, an adhesive ring is provided between the membrane plate and the gas permeation membrane material.

[0016] The rubber rings provided in the membrane tank of this invention include large rubber rings and small rubber rings.

[0017] The membrane plate of the present invention is provided with an internal threaded hole, and the cap is provided with an external threaded hole.

[0018] Preferably, the diameter of the metal mesh is 0.5-5 cm, for example, it can be 0.5 cm, 1 cm, 1.5 cm, 2 cm, 2.5 cm, 3 cm, 3.5 cm, 4 cm, 4.5 cm or 5 cm, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0019] Preferably, the cover is provided with a temperature monitoring component and a temperature data transmission line.

[0020] Preferably, the constant temperature chamber is equipped with a constant temperature chamber temperature indicator and a constant temperature chamber operation indicator.

[0021] As a preferred embodiment of the present invention, the membrane vacuum control system is connected to a vacuum pump.

[0022] As a preferred technical solution of the present invention, the on-membrane feed gas inlet system is provided with a feed gas inlet valve, a gas storage tank, an on-membrane vacuum valve, a pipeline cooler and a pipeline heater in sequence along the airflow direction.

[0023] Preferably, the pipe cooler has a cooling water inlet and a cooling water outlet connected to the side walls at both ends.

[0024] Preferably, a gas switch is provided on the gas inlet pipe connected to the raw material gas inlet.

[0025] As a preferred technical solution of the present invention, a purge gas valve and a check valve are sequentially provided on the air intake pipe connected to the purge gas inlet along the airflow direction.

[0026] As a preferred embodiment of the present invention, the under-membrane vacuum control system is connected to a vacuum pump.

[0027] Preferably, the pipeline of the sub-membrane vacuum control system is equipped with a sub-membrane vacuum valve.

[0028] The pipelines of the flow testing system and the sub-membrane vacuum control system described in this invention are all connected to the same main pipe, which is equipped with a sub-membrane vacuum valve. The main pipe is divided into two branches: one branch is connected to the vacuum pump via the sub-membrane vacuum interface valve, and the other branch is connected to the flow meter via the flow meter valve.

[0029] Preferably, the chromatographic detection system is equipped with a chromatographic valve on its pipeline.

[0030] As a preferred technical solution of the present invention, the computer control system includes a central control unit and power indicator area, a gas circuit instrument area, a central control unit protection panel and communication interface area, and a flow monitoring component data port.

[0031] The testing equipment provided by this invention also includes a central control unit and power indicator area, a central control unit switch, a temperature display, a buzzer, an instrument power indicator, a membrane tank, a constant temperature chamber, a constant temperature chamber temperature indicator, a constant temperature chamber operation indicator, a gas path instrument area, heat dissipation holes, a central control unit protection panel and communication interface area, an inlet valve area, an internal triangular switch, a USB port, an HDMI port, a purge gas valve, a raw material gas inlet valve, a sub-membrane vacuum pressure gauge, an outlet valve area, a membrane vacuum valve, a gas switch, a chromatograph valve, a sub-membrane vacuum valve, a membrane vacuum interface, a sub-membrane gas chromatography outlet, a sub-membrane gas outlet, a switch, a power socket, a flow meter data port, a cooling fan, and a support. The distribution of the above components on the surface of the housing and their internal connections can be adjusted according to the production needs of the device, and are not specifically limited here.

[0032] Secondly, the present invention provides a plate membrane differential pressure method for testing gas permeation performance, wherein the testing process is performed in the testing equipment described in the first aspect.

[0033] As a preferred technical solution of the present invention, the constant pressure variable volume method in the testing process includes the following steps:

[0034] The gas permeation membrane material is placed in the membrane tank. The temperature of the testing equipment is adjusted by the temperature control system, and the vacuum inside the testing equipment is adjusted by the vacuum control system. The purge gas enters the space below the membrane tank through the under-membrane purge gas inlet system to a certain pressure. The feed gas enters the space below the membrane tank through the on-membrane feed gas inlet system and the gas permeation membrane material. The gas below the membrane tank enters the flow test system to measure the gas flow rate or the gas composition is detected by the chromatographic detection system. The permeation performance is calculated from the gas flow rate.

[0035] This invention uses the constant pressure variable volume method to measure the permeation performance of single or mixed gases, including the following steps: Selecting a membrane cell of suitable size according to the size of the experimental sample and installing it in a constant temperature chamber; placing a porous metal mesh inside the membrane cell; applying vacuum grease to the lower edge of the gas permeation membrane material; placing the large and small rubber rings on the gas permeation membrane material; gently placing the membrane plate and fixing it using the internal screw holes; subsequently, placing the cap and fixing it using the external screw holes; after the membrane cell and gas permeation membrane material are installed, turning on all power to the device and connecting the feed gas inlet to the gas cylinder; checking that the feed gas inlet valve, purge gas valve, membrane vacuum valve, gas switch, chromatograph valve, under-membrane vacuum valve, flow meter valve, and under-membrane vacuum interface valve are all closed; and controlling the vacuum... The system adjusts the internal vacuum of the equipment, turns on the vacuum pump, and opens the vacuum interface valve and the vacuum valve under the membrane to evacuate the space under the membrane. After a period of time, it opens the vacuum valve on the membrane and the gas switch to evacuate the space above the membrane and the gas storage tank. Then, it sequentially closes the gas switch, the vacuum valve on the membrane, the vacuum valve under the membrane, and the vacuum pump. Gas is then introduced into the gas storage tank through the gas input system to the required experimental pressure. The gas cylinder is opened, and the raw material gas inlet valve is opened to allow gas to enter the gas storage tank through the raw material gas inlet. The gas switch is opened to allow gas to enter the space above the membrane cell. The space under the membrane can be filled with an appropriate amount of helium, argon, nitrogen, or the same gas as the test gas. The operation involves opening the purge gas valve to allow gas to enter the space below the membrane cell through the purge gas inlet until a certain pressure is reached. At this point, the flow meter valve is opened, and the gas flow rate is recorded and displayed by the flow meter. After the experiment, the gas in the gas storage tank is completely discharged. For special gases, a tail gas treatment device can be installed. All valves and power are turned off, the gas-permeable membrane material is removed, and the experiment is terminated.

[0036] As a preferred technical solution of the present invention, the constant volumetric pressure change method in the testing process includes the following steps:

[0037] The gas permeation membrane material is placed in the membrane tank. The temperature of the testing equipment is adjusted by the temperature control system, and the vacuum inside the testing equipment is adjusted by the vacuum control system to maintain a vacuum state in the space below the membrane tank. The feed gas enters the fixed volume space below the membrane tank through the feed gas inlet system on the membrane and the gas permeation membrane material. The permeation performance is calculated by the pressure change in the fixed volume space below the membrane tank.

[0038] This invention uses the constant volume pressure swing method to measure the permeation performance of single or mixed gases, comprising the following steps: Selecting a membrane cell of suitable size according to the size of the experimental sample and installing it in a constant temperature chamber; placing a porous metal mesh inside the membrane cell; applying vacuum grease to the lower edge of the gas permeation membrane material; placing the large and small rubber rings on the gas permeation membrane material; gently placing the membrane plate and securing it with internal screw holes; subsequently, placing the cap and securing it with external screw holes; after the membrane cell and gas permeation membrane material are installed, turning on all power to the device and connecting the feed gas inlet to the gas cylinder; checking that the feed gas inlet valve, purge gas valve, membrane vacuum valve, gas switch, chromatograph valve, under-membrane vacuum valve, flow meter valve, and under-membrane vacuum interface valve are all closed; adjusting the internal vacuum of the equipment through the vacuum control system and opening the vacuum valve. Open the vacuum pump, open the vacuum interface valve and the vacuum valve under the membrane to evacuate the space under the membrane. After a period of time, open the vacuum valve on the membrane and the gas switch to evacuate the space above the membrane and the gas storage tank. Then, sequentially close the gas switch, the vacuum valve on the membrane, the vacuum valve under the membrane, and the vacuum pump. Fill the gas storage tank with gas through the gas input system to the required experimental pressure. Open the gas cylinder and the raw material gas inlet valve to introduce gas into the gas storage tank through the raw material gas inlet. Open the gas switch to introduce gas into the area above the membrane cell. Maintain a vacuum under the membrane. The gas will spontaneously permeate into the fixed volume space under the membrane, and the pressure will gradually increase during the permeation process. After the experiment is completed, completely discharge the gas from the gas storage tank. For special gases, a tail gas treatment device can be installed. Close all valves and power supply, remove the gas permeate membrane material, and end the experiment.

[0039] Compared with existing technical solutions, the present invention has at least the following beneficial effects:

[0040] (1) The plate membrane differential pressure gas permeation performance testing equipment provided by the present invention has high integration and environmental control functions, and can perform in-situ measurements under constant temperature or variable temperature conditions;

[0041] (2) The constant pressure variable volume method or constant volume variable pressure method can be used to test the permeation performance of plate membrane materials, thereby obtaining the permeation performance of plate membranes and the intrinsic gas permeation properties of their materials. According to the structural characteristics of plate membranes, this equipment can also measure the relevant gas permeation and air permeability properties of various gas separation membranes, packaging materials and clothing fabrics. Attached Figure Description

[0042] Figure 1 This is a process piping and instrumentation diagram of the plate membrane differential pressure gas permeation performance testing equipment provided in Embodiment 1 of the present invention;

[0043] Figure 2 This is a front view schematic diagram of the plate membrane differential pressure method gas permeation performance testing device provided in Embodiment 1 of the present invention;

[0044] Figure 3These are left and right view schematic diagrams of the plate membrane differential pressure gas permeation performance testing device provided in Embodiment 1 of the present invention;

[0045] Figure 4 This is a schematic diagram of the membrane tank and clamping assembly of the plate membrane differential pressure gas permeation performance testing device provided in Embodiment 1 of the present invention;

[0046] Figure 5 This is a flowchart of the process for adjusting the vacuum under the membrane and measuring the flow rate of the plate membrane differential pressure gas permeation performance testing device provided in Embodiment 1 of the present invention;

[0047] Figure 6 This is a rear view schematic diagram of the plate membrane differential pressure method gas permeation performance testing device provided in Embodiment 1 of the present invention;

[0048] Figure 7 This is a top view schematic diagram of the plate membrane differential pressure method gas permeation performance testing device provided in Embodiment 1 of the present invention;

[0049] In the diagram, 1-membrane tank, 2-central control unit and power indicator area, 3-thermal chamber, 4-support, 5-gas path instrument area, 6-heat dissipation holes, 7-central control unit protection panel and communication interface area, 8-inlet valve area, 9-vacuum pressure gauge under the membrane, 10-outlet valve area, 11-switch, 12-power socket, 13-cooling fan, 14-central control unit switch, 15-temperature display, 16-buzzer, 17-instrument power indicator, 18-thermal chamber temperature indicator, 19-thermal chamber operation indicator, 20-internal triangular switch, 21-USB, 22-HDMI, 23-purge gas valve, 24-feed gas inlet valve, 25-purge gas inlet, 26-feed gas inlet, 27-vacuum valve dustproof baffle switch, 28-vacuum valve switch, 29-right valve area baffle switch, 30-vacuum valve on the membrane, 31-gas switch, 32-chromatograph valve Door, 33-Under-membrane vacuum valve, 34-Upper-membrane vacuum interface, 35-Under-membrane gas chromatograph outlet, 36-Under-membrane gas outlet, 37-Flow meter data port, 38-External threaded hole, 39-Internal threaded hole, 40-Porous metal mesh, 41-Temperature data transmission line, 42-Thermometer, 43-Cap, 44-Membrane pressure plate, 45-Large rubber ring, 46-Small rubber ring, 47-Gas permeation membrane material, 48-Feed gas inlet 49-Membrane tank purge gas inlet, 50-Purge gas outlet, 51-Pipe cooler, 52-Pipe heater, 53-Check valve, 54-Upper pressure gauge of membrane tank, 55-Air storage tank, 56-Lower pressure gauge of membrane tank, 57-T-way valve, 58-Flow meter valve, 59-Lower vacuum interface valve of membrane, 60-Flow meter, 61-Air storage tank pressure gauge, 62-Gas chromatograph connection pipeline, 63-Cooling water inlet and cooling water outlet. Detailed Implementation

[0050] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0051] It should be clarified that any use of the process provided in the embodiments of the present invention or any substitution or change of conventional data falls within the protection and disclosure scope of the present invention.

[0052] Example 1

[0053] This embodiment provides a plate membrane differential pressure method gas permeation performance testing device. The testing device includes a membrane tank, a vacuum control system, a computer control system, a feed gas inlet system above the membrane, a purge gas inlet system below the membrane, a temperature control system, and a flow rate and composition testing system.

[0054] The vacuum control system includes an on-membrane vacuum control system and a sub-membrane vacuum control system. The on-membrane vacuum control system is connected to a vacuum pump. The on-membrane feed gas inlet system is provided with a feed gas inlet valve 24, a gas storage tank 55, an on-membrane vacuum valve 30, a pipe cooler 51, and a pipe heater 52 in sequence along the airflow direction. The pipe cooler 52 has a cooling water inlet and a cooling water outlet 38 connected to its two end side walls, respectively. A gas switch 31 is provided on the inlet pipe connected to the feed gas inlet 26. The sub-membrane vacuum control system is connected to a vacuum pump, and a sub-membrane vacuum valve 33 is provided on the pipe. A chromatograph valve 32 is provided on the pipe of the chromatographic detection system.

[0055] The temperature control system includes a constant temperature chamber 3, and the membrane tank 1 is placed in the constant temperature chamber 3;

[0056] The flow rate and composition testing system includes a flow rate testing system and a chromatographic detection system.

[0057] A raw material gas inlet is provided above the membrane tank. The raw material gas inlet is connected to an air inlet pipe, which is divided into two branches: one branch is connected to the raw material gas inlet system on the membrane, and the other branch is connected to the vacuum control system on the membrane.

[0058] The pipelines of the flow testing system and the sub-membrane vacuum control system are both connected to the same main pipe, which is equipped with a sub-membrane vacuum valve 33. The main pipe is divided into two branches: one branch is connected to the vacuum pump via a sub-membrane vacuum interface valve 59, and the other branch is connected to the flow meter 60 via a flow meter valve 58. A tee 57 is provided at the branch.

[0059] A purge gas inlet 49 is provided below the membrane tank. The purge gas inlet 49 is connected to an air inlet pipe, which is connected to the under-membrane purge gas intake system. The air inlet pipe connected to the purge gas inlet is provided with a purge gas inlet 25, a purge gas valve 23 and a check valve 53 in sequence along the airflow direction.

[0060] An exhaust port is provided below the membrane tank, and the exhaust port is connected to an exhaust pipe. The exhaust pipe is divided into two branches, one of which is connected to the flow test system and the other of which is connected to the chromatography detection system.

[0061] The membrane tank includes, from top to bottom, a cover 43, a membrane pressure plate 44, a gas permeation membrane material 47, and a metal mesh 40. A large rubber ring 45 and a small rubber ring 46 are provided between the membrane pressure plate 44 and the gas permeation membrane material 47. A temperature monitoring component 42 and a temperature data transmission line 41 are provided on the cover 43. A constant temperature chamber 3 is provided with a constant temperature chamber temperature indicator 18 and a constant temperature chamber operation indicator 19. A raw material gas inlet 48 and a purge gas outlet 50 are provided on the membrane tank.

[0062] The computer control system includes a central control unit and power indicator area 2, a gas circuit instrument area 5, a central control unit protection panel and communication interface area 7, and a flow monitoring component data port 37.

[0063] like Figure 2 As shown, the front left side of the device features a central control unit and power indicator area 2, a central control unit switch 14, a temperature display 15, a buzzer 16, and an instrument power indicator 17. The middle section includes a membrane tank 1, a constant temperature chamber 3, a constant temperature chamber temperature indicator 18, and a constant temperature chamber operation indicator 19. The right side features a gas path instrument area 5 and heat dissipation holes 6. Figure 3 As shown, the left side of the device includes a central control panel and communication interface area 7, an inlet valve area 8, an internal triangular switch 20, a USB port 21, an HDMI port 22, a purge gas valve 23, and a feed gas inlet valve 24. The right side includes a sub-membrane vacuum pressure gauge 9, an outlet valve area 10, an on-membrane vacuum valve 30, a gas switch 31, a chromatograph valve 32, a sub-membrane vacuum valve 33, an on-membrane vacuum interface 34, a sub-membrane gas chromatography outlet 35, and a sub-membrane gas outlet 36. Figure 6 As shown, the back of the device has a switch 11, a power socket 12, and a flow meter data port 37; Figure 7 As shown, the device is equipped with a cooling fan 13 at the top and a support 4 at the bottom.

[0064] Example 2

[0065] This embodiment provides a plate membrane differential pressure method for testing gas permeability performance. The testing process uses the testing equipment provided in Embodiment 1 and includes the following steps:

[0066] The permeation performance of the graphene oxide confined 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid gas separation membrane (GO-BMIM BF4) was measured using the constant pressure variable volume method. Based on the size of the experimental sample, a 25mm diameter membrane cell with a 16mm porous metal mesh was selected and installed in a constant temperature chamber. The 16mm porous metal mesh was placed inside the membrane cell, and vacuum silicone grease was applied to the lower edge of the gas permeation membrane material. The large and small rubber rings were then placed on the gas permeation membrane material, and the membrane plate was gently placed and fixed using the internal screw holes. Subsequently, the cap was placed and fixed using the external screw holes.

[0067] After the membrane tank and gas permeation membrane material are installed, turn on all the power to the device. First, turn on the switch on the back of the equipment, then turn on the central control switch on the front of the equipment. Connect the raw material gas inlet to the gas cylinder.

[0068] Check that the feed gas inlet valve, purge gas valve, membrane vacuum valve, gas switch, chromatograph valve, membrane vacuum valve, flow meter valve and membrane vacuum interface valve are kept closed.

[0069] Adjust the internal vacuum of the equipment through the vacuum control system, turn on the vacuum pump, open the vacuum interface valve and the vacuum valve under the membrane, and evacuate the space under the membrane for about 5 minutes. Then, open the vacuum valve on the membrane and the gas switch to evacuate the space on the membrane and the gas storage tank. After the whole process lasts for 2 hours, turn off the gas switch, the vacuum valve on the membrane, the vacuum valve under the membrane and the vacuum pump in sequence.

[0070] Open the feed gas inlet valve to introduce gas into the storage tank through the feed gas inlet. Open the gas switch and adjust the feed gas inlet valve to bring the carbon dioxide pressure above the membrane tank to 0.50 bar, then introduce gas into the upper part of the membrane tank. Open the purge gas valve to introduce gas into the lower part of the membrane tank through the purge gas inlet until the gauge pressure reaches 0 kPa. At this point, open the flow meter valve, and the gas flow rate is recorded and displayed by the flow meter. The test time is 1 hour.

[0071]

[0072] After completely purging the gas from the gas tank, shut off all valves and power, remove the gas permeation membrane material, and end the experiment. The calculated result is: flux of 10.08 GPUs.

[0073] Example 3

[0074] This embodiment provides a plate membrane differential pressure method for testing gas permeability performance. The testing process uses the testing equipment provided in Embodiment 1 and includes the following steps:

[0075] The constant volumetric pressure swing method was used to measure the gas separation membrane of porous nylon impregnated with 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid. Based on the size of the experimental sample, a 25mm diameter membrane cell with a 16mm porous metal mesh was selected and installed in a constant temperature chamber. The 16mm porous metal mesh was placed inside the membrane cell. Vacuum silicone grease was applied to the lower edge of the gas permeation membrane material GO-BMIM BF4. Large and small rubber rings were then placed on top of the gas permeation membrane material. The membrane plate was gently placed and secured using the internal screw holes. The cap was then placed and secured using the external screw holes. After the membrane cell and gas permeation membrane material were installed, all power to the device was turned on. First, the switch on the back of the device was turned on, then the central control switch on the front of the device was turned on. The raw material gas inlet was connected to the gas cylinder.

[0076] Check that the feed gas inlet valve, purge gas valve, membrane vacuum valve, gas switch, chromatograph valve, membrane vacuum valve, flow meter valve and membrane vacuum interface valve are kept closed.

[0077] Adjust the internal vacuum of the equipment through the vacuum control system, turn on the vacuum pump, open the vacuum interface valve under the membrane and the vacuum valve under the membrane, and evacuate the space under the membrane for about 5 minutes. Then, open the vacuum valve on the membrane and the gas switch to evacuate the space on the membrane and the gas storage tank. After the whole process lasts for 2 hours, turn off the gas switch, the vacuum valve on the membrane, the vacuum valve under the membrane and the vacuum pump in sequence.

[0078] Open the feed gas inlet valve to introduce gas into the gas storage tank through the feed gas inlet. Open the gas switch and adjust the feed gas inlet valve to bring the carbon dioxide pressure above the membrane tank to 0.50 bar, then introduce gas into the area above the membrane tank. Maintain a vacuum under the membrane. The gas spontaneously permeates into the fixed volume space under the membrane, and the pressure gradually increases during the permeation process. The actual test time was 1 hour.

[0079]

[0080] After completely purging the gas from the storage tank, shutting off all valves and power, removing the gas permeation membrane material, the experiment was concluded, and the calculated result was: flux of 3.78 GPUs.

[0081] Example 4

[0082] This embodiment provides a plate membrane differential pressure method for testing gas permeability performance. The testing process uses the testing equipment provided in Embodiment 1 and includes the following steps:

[0083] The gas permeability of plastic food sealing bags was measured using the constant volume pressure variation method. The test conditions were room temperature, 1 atm pressure, and nitrogen gas as the standard for measuring its permeability. Based on the size of the experimental sample, a 25mm diameter membrane cell with a 16mm porous metal mesh was selected and installed in a constant temperature chamber. The 16mm porous metal mesh was placed inside the membrane cell. Vacuum silicone grease was applied to the lower edge of the gas permeation membrane material GO-BMIM BF4. The large and small rubber rings were placed on the gas permeation membrane material, and the membrane plate was gently placed and fixed using the internal screw holes. The cap was then placed and fixed using the external screw holes. After the membrane cell and gas permeation membrane material were installed, all power supplies to the device were turned on. First, the switch on the back of the device was turned on, and then the central control switch on the front of the device was turned on. The raw material gas inlet was connected to the gas cylinder.

[0084] Check that the feed gas inlet valve, purge gas valve, membrane vacuum valve, gas switch, chromatograph valve, membrane vacuum valve, flow meter valve and membrane vacuum interface valve are kept closed.

[0085] Adjust the internal vacuum of the equipment through the vacuum control system, turn on the vacuum pump, open the vacuum interface valve under the membrane and the vacuum valve under the membrane, and evacuate the space under the membrane for about 5 minutes. Then, open the vacuum valve on the membrane and the gas switch to evacuate the space on the membrane and the gas storage tank. After the whole process lasts for 2 hours, turn off the gas switch, the vacuum valve on the membrane, the vacuum valve under the membrane and the vacuum pump in sequence.

[0086] Nitrogen gas was introduced into the storage tank by opening the feed gas inlet valve. The gas switch was then turned on to adjust the feed gas inlet valve so that the carbon dioxide pressure above the membrane tank reached 1.0 bar. Gas was then introduced into the membrane tank while maintaining a vacuum under the membrane. The gas spontaneously permeated into the fixed volume space under the membrane, and the pressure gradually increased during the permeation process. The actual test time was 72 hours.

[0087] Using the same calculation method as in Example 3, the gas permeability of the packaging material can be calculated to be 0.0025 GPU.

[0088] Example 5

[0089] This embodiment provides a plate membrane differential pressure method for testing gas permeability performance. The testing process uses the testing equipment provided in Embodiment 1 and includes the following steps:

[0090] The constant pressure and variable volume method was used to measure the permeation performance of the graphene oxide confined 1-methyl-3-methylimidazolium tetrafluoroborate ionic liquid gas separation membrane (GO-MMIM BF4) with carbon dioxide and hydrogen gases respectively. Based on the size of the experimental sample, a 25mm diameter membrane cell with a 16mm porous metal mesh was selected and installed in a constant temperature chamber. The 16mm porous metal mesh was placed inside the membrane cell. Vacuum silicone grease was applied to the lower edge of the GO-MMIM BF4 gas permeation membrane material. Large and small rubber rings were then placed on top of the gas permeation membrane material. The membrane plate was gently placed and secured using the internal screw holes. The cap was then placed and secured using the external screw holes. After the membrane cell and gas permeation membrane material were installed, all power supplies to the device were turned on. First, the switch on the back of the device was turned on, then the central control switch on the front of the device was turned on. The raw material gas inlet was connected to the gas cylinder.

[0091] Check that the feed gas inlet valve, purge gas valve, membrane vacuum valve, gas switch, chromatograph valve, membrane vacuum valve, flow meter valve and membrane vacuum interface valve are kept closed.

[0092] Adjust the internal vacuum of the equipment through the vacuum control system, turn on the vacuum pump, open the vacuum interface valve under the membrane and the vacuum valve under the membrane, and evacuate the space under the membrane for about 5 minutes. Then, open the vacuum valve on the membrane and the gas switch to evacuate the space on the membrane and the gas storage tank. After the whole process lasts for 2 hours, turn off the gas switch, the vacuum valve on the membrane, the vacuum valve under the membrane and the vacuum pump in sequence.

[0093] Open the feed gas inlet valve to introduce gas into the storage tank through the feed gas inlet. Open the gas switch and adjust the feed gas inlet valve to bring the carbon dioxide or hydrogen pressure above the membrane tank to 0.50 bar, then introduce the gas into the membrane tank. Open the purge gas valve to introduce gas into the lower part of the membrane tank through the purge gas inlet until the gauge pressure reaches 0 kPa. At this point, open the flow meter valve, and the gas flow rate is recorded and displayed by the flow meter. The test time is 3 hours. After the test time for one set is reached, open the feed gas inlet valve again to purge the equipment, with the range of change being 0.5-3.0 bar.

[0094] After the experiment was completed, the relevant data were processed according to the calculation method of Example 2 to obtain the calculation results shown in Table 1 below. At the same time, the ideal selectivity can be obtained by dividing the flux of the two.

[0095] Table 1

[0096]

[0097] Example 6

[0098] This embodiment provides a plate membrane differential pressure method for testing gas permeability performance. The testing process uses the testing equipment provided in Embodiment 1 and includes the following steps:

[0099] The permeation performance of the graphene oxide confined 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid gas separation membrane (GO-BMIM BF4) was measured using the variable temperature, constant pressure, and variable volume method with carbon dioxide and hydrogen gases respectively. Based on the size of the experimental sample, a 25mm diameter membrane cell with a 16mm porous metal mesh was selected and installed in a constant temperature chamber. The 16mm porous metal mesh was placed inside the membrane cell. Vacuum silicone grease was applied to the lower edge of the GO-BMIM BF4 gas permeation membrane material. Large and small rubber rings were then placed on top of the gas permeation membrane material. The membrane plate was gently placed and secured using the internal screw holes. The cap was then placed and secured using the external screw holes. After the membrane cell and gas permeation membrane material were installed, all power supplies to the device were turned on. First, the switch on the back of the device was turned on, then the central control switch on the front of the device was turned on. The raw material gas inlet was connected to the gas cylinder.

[0100] Check that the feed gas inlet valve, purge gas valve, membrane vacuum valve, gas switch, chromatograph valve, membrane vacuum valve, flow meter valve and membrane vacuum interface valve are kept closed.

[0101] Adjust the internal vacuum of the equipment through the vacuum control system, turn on the vacuum pump, open the vacuum interface valve under the membrane and the vacuum valve under the membrane, and evacuate the space under the membrane for about 5 minutes. Then, open the vacuum valve on the membrane and the gas switch to evacuate the space on the membrane and the gas storage tank. After the whole process lasts for 2 hours, turn off the gas switch, the vacuum valve on the membrane, the vacuum valve under the membrane and the vacuum pump in sequence.

[0102] Open the feed gas inlet valve to introduce gas into the storage tank through the feed gas inlet. Open the gas switch and adjust the feed gas inlet valve to bring the carbon dioxide or hydrogen pressure above the membrane tank to 0.50 bar, then introduce the gas into the membrane tank. Open the purge gas valve and introduce gas into the lower part of the membrane tank through the purge gas inlet until the gauge pressure reaches 0 kPa. After filling, open the equipment's horizontal temperature chamber. After the temperature stabilizes at 25 ℃, open the flow meter valve. The gas flow rate is recorded and displayed by the flow meter. The test time is 3 hours. After completing one set of test times, adjust the temperature chamber temperature again, with a range of 25-50 ℃.

[0103] After the experiment was completed, the relevant data were processed according to the calculation method in Example 2 to obtain the calculation results shown in Table 2 below. At the same time, the ideal selectivity can be obtained by dividing the flux of the two.

[0104] Table 2

[0105]

[0106] In summary, the plate membrane differential pressure method gas permeability testing equipment provided in this application features high integration and environmental control capabilities, enabling in-situ measurements under constant or variable temperature conditions. During the testing process, the plate membrane is placed in the membrane tank and sealed by gaskets and pressure plates. The permeability performance of the plate membrane material can then be tested using either the constant pressure variable volume method or the constant volume variable pressure method, thereby obtaining the permeability performance of the plate membrane and its intrinsic gas permeability properties. Similarly, based on the structural characteristics of plate membranes, this equipment can also measure the relevant gas permeability and air permeability properties of various gas separation membranes, packaging materials, and clothing fabrics.

[0107] The present invention has been illustrated with the above embodiments to illustrate its detailed structural features. However, the present invention is not limited to the above detailed structural features, that is, it does not mean that the present invention must rely on the above detailed structural features to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions for the components used in the present invention, additions of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A plate-type membrane differential pressure method gas permeation performance testing device, characterized in that, The testing equipment includes a membrane tank, a vacuum control system, a computer control system, a feed gas inlet system above the membrane, a purge gas inlet system below the membrane, a temperature control system, and a flow rate and composition testing system. The vacuum control system includes an on-membrane vacuum control system and a below-membrane vacuum control system; The temperature control system includes a constant temperature chamber, and the membrane tank is placed in the constant temperature chamber; The flow rate and composition testing system includes a flow rate testing system and a chromatographic detection system. A raw material gas inlet is provided above the membrane tank. The raw material gas inlet is connected to an air inlet pipe, which is divided into two branches: one branch is connected to the raw material gas inlet system on the membrane, and the other branch is connected to the vacuum control system on the membrane. A purge gas inlet is provided below the membrane tank, and the purge gas inlet is connected to an air inlet pipe, which is connected to the under-membrane purge gas inlet system. An exhaust port is provided below the membrane tank, and the exhaust port is connected to an exhaust pipe. The exhaust pipe is divided into two branches, one of which is connected to the flow test system and the other of which is connected to the chromatography detection system.

2. The testing equipment according to claim 1, characterized in that, The membrane tank includes, from top to bottom, a cap, a membrane plate, a gas permeation membrane material, and a metal mesh; Preferably, an adhesive ring is provided between the membrane plate and the gas permeation membrane material; Preferably, the diameter of the metal mesh is 0.5-5 cm; Preferably, the cover is provided with a temperature monitoring component and a temperature data transmission line; Preferably, the constant temperature chamber is equipped with a constant temperature chamber temperature indicator and a constant temperature chamber operation indicator.

3. The testing equipment according to claim 1 or 2, characterized in that, The membrane vacuum control system is connected to the vacuum pump.

4. The testing equipment according to any one of claims 1 to 3, characterized in that, The on-membrane feed gas intake system is provided with a feed gas intake valve, a gas storage tank, an on-membrane vacuum valve, a pipeline cooler, and a pipeline heater in sequence along the airflow direction; Preferably, the pipe cooler has a cooling water inlet and a cooling water outlet connected to the side walls at both ends, respectively; Preferably, a gas switch is provided on the gas inlet pipe connected to the raw material gas inlet.

5. The testing equipment according to any one of claims 1 to 4, characterized in that, The purge gas inlet is connected to an air intake pipe with a purge gas valve and a check valve arranged sequentially along the airflow direction.

6. The testing equipment according to any one of claims 1 to 5, characterized in that, The under-membrane vacuum control system is connected to the vacuum pump; Preferably, a sub-membrane vacuum valve is provided on the pipeline of the sub-membrane vacuum control system; Preferably, the chromatographic detection system is equipped with a chromatographic valve on its pipeline.

7. The testing equipment according to any one of claims 1 to 6, characterized in that, The computer control system includes a central control unit and power indicator area, a gas circuit instrument area, a central control unit protection panel and communication interface area, and a flow monitoring component data port.

8. A plate-type membrane differential pressure method for testing gas permeability, characterized in that, The testing process is carried out in the testing equipment described in any one of claims 1 to 7.

9. The testing process according to claim 8, characterized in that, The constant pressure variable volume method in the testing process includes the following steps: The gas permeation membrane material is placed in the membrane tank. The temperature of the testing equipment is adjusted by the temperature control system, and the vacuum inside the testing equipment is adjusted by the vacuum control system. The purge gas enters the space below the membrane tank through the under-membrane purge gas inlet system to a certain pressure. The feed gas enters the space below the membrane tank through the on-membrane feed gas inlet system and the gas permeation membrane material. The gas below the membrane tank enters the flow test system to measure the gas flow rate or the gas composition is detected by the chromatographic detection system. The permeation performance is calculated from the gas flow rate.

10. The testing process according to claim 8, characterized in that, The constant volumetric pressure change method in the aforementioned testing process includes the following steps: The gas permeation membrane material is placed in the membrane tank. The temperature of the testing equipment is adjusted by the temperature control system, and the vacuum inside the testing equipment is adjusted by the vacuum control system to maintain a vacuum state in the space below the membrane tank. The feed gas enters the fixed volume space below the membrane tank through the feed gas inlet system on the membrane and the gas permeation membrane material. The permeation performance is calculated by the pressure change in the fixed volume space below the membrane tank.

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