Desorption separation system and method for electronic grade acetylene

Abstract

The application discloses a kind of electronic grade acetylene desorption separation system and method, and desorption separation system includes desorption tank, separation tank body, filter membrane and acetylene cylinder.The upper portion of the desorption tank has a discharge port.The separation tank body is arranged in the upper portion of the desorption tank, the separation tank body has oppositely arranged gas inlet and gas outlet, the gas inlet of the separation tank body is communicated with the discharge port of the desorption tank, and the gas outlet is located above the gas inlet.The filter membrane is installed in the separation tank body, the filter membrane has opposite first side and second side, the first side is communicated with the gas inlet, and the second side is communicated with the gas outlet.The gas outlet of the separation tank body is communicated with the acetylene cylinder.Wherein, filter membrane is polytetrafluoroethylene filter membrane, crosslinked polyvinylidene fluoride filter membrane, polyphenylene sulfide filter membrane or polypropylene filter membrane.

Description

Technical Field

[0001] This invention relates to a gas purification system and method, and more particularly to a desorption and separation system and method for electronic-grade acetylene. Background Technology

[0002] Electronic-grade acetylene (with a purity requirement of 4N or higher) is a key electronic specialty gas in the semiconductor, integrated circuit, and other electronics industries. Its purity directly affects the performance and yield of electronic devices. Due to the flammable and explosive nature of acetylene, the most common industrial purification method is the absorption-desorption process. This involves selectively absorbing impurities from crude acetylene using a high-purity solvent, followed by desorption to separate high-purity acetylene. Examples of solvents used include N,N-dimethylformamide (DMF) and acetone.

[0003] However, during desorption, when electronic-grade acetylene escapes from the desorption tank, it often carries away a large amount of solvent in aerosol form, which then enters subsequent pipelines. This solvent carryover not only causes blockages and metering inaccuracies in downstream equipment, and even damages instruments and equipment, but also results in significant solvent waste, leading to insufficient total solvent volume in the absorption tank, decreased absorption-desorption efficiency, and consequently affecting the yield of electronic-grade acetylene and increasing production costs. Existing technologies often use condensers to intercept the carried-out solvent through phase change, but this method has low separation efficiency and cannot completely solve the solvent carryover problem; some solvent aerosols are still carried to the downstream lines by the acetylene.

[0004] Therefore, to address the aforementioned technical problems, it is necessary to provide a desorption and separation system and method for electronic-grade acetylene that is compatible with the mainstream purification process of acetylene absorption-desorption and enables solvent recycling to solve the problem of solvent carry-out. Summary of the Invention

[0005] The purpose of this invention is to provide a desorption and separation system and method for electronic-grade acetylene, which can be adapted to the mainstream purification process of acetylene absorption-desorption, realize the separation of solvent and acetylene, avoid the swelling of the filter membrane due to solvent corrosion, and allow the separated solvent to be recycled by gravity, thus solving the problem of solvent carry-out.

[0006] To achieve the above objectives, a specific embodiment of the present invention provides the following technical solution:

[0007] An embodiment of the present invention provides a desorption and separation system for electronic-grade acetylene, comprising:

[0008] A desorption vessel, wherein the desorption vessel has a discharge port at its top;

[0009] A separation tank is disposed above the desorption tank. The separation tank has an air inlet and an air outlet arranged opposite to each other. The air inlet of the separation tank is connected to the outlet of the desorption tank, and the air outlet is located above the air inlet.

[0010] A filter membrane is installed inside the separation tank. The filter membrane has a first side and a second side opposite to each other. The first side is connected to the air inlet, and the second side is connected to the air outlet.

[0011] An acetylene gas cylinder, wherein the outlet of the separation tank is connected to the acetylene gas cylinder;

[0012] The filter membrane is a polytetrafluoroethylene (PTFE) filter membrane, a cross-linked polyvinylidene fluoride (PVDF) filter membrane, a polyphenylene sulfide (PPS) filter membrane, or a polypropylene (PP) filter membrane.

[0013] In one or more embodiments of the present invention, the filter membrane has a plurality of pores, wherein the pore size of the plurality of pores is between 0.01 μm and 0.1 μm, and the porosity of the filter membrane is between 70% and 80%, and the air permeability resistance of the filter membrane is less than or equal to 5 kPa; and / or,

[0014] The contact angle of N,N-dimethylformamide (DMF) and acetone with the filter membrane is greater than or equal to 95 degrees.

[0015] In one or more embodiments of the present invention, the filter membrane is arranged to form a cylindrical structure, a first side of the filter membrane is located inside the cylindrical structure, a second side of the filter membrane is located outside the cylindrical structure, a first end of the cylindrical structure is an open end and has a connection port, and the inner side of the cylindrical structure is connected to the air inlet through the connection port.

[0016] In one or more embodiments of the present invention, a sealing gasket is further included, the sealing gasket being disposed between the connection port and the air inlet, wherein the sealing gasket is a perfluoroether sealing gasket or a fluoropolymer-coated sealing gasket.

[0017] In one or more embodiments of the present invention, the second end of the cylindrical structure is a closed end and is opposite to the first end; and,

[0018] The desorption separation system further includes an elastic limiting member disposed between the inner wall of the separation tank and the second end; wherein the elastic force generated by the elastic limiting member corresponds to the axial direction of the cylindrical structure.

[0019] In one or more embodiments of the present invention, the separation tank further includes a purge and replacement port, the location of which corresponds to the second side of the filter membrane.

[0020] In one or more embodiments of the present invention, pressure sensors are respectively provided at the air inlet and the air outlet.

[0021] In one or more embodiments of the present invention, the separation tank includes a first part and a second part that are detachably connected, the first part being provided with the air inlet and the second part being provided with the air outlet.

[0022] In one or more embodiments of the present invention, the separation tank further includes a solvent drain port, the solvent drain port being positioned corresponding to the second side of the filter membrane.

[0023] An embodiment of the present invention further provides a method for desorption and separation of electronic-grade acetylene, comprising:

[0024] The separation tank of the above-mentioned desorption separation system is placed above the desorption tank, and the outlet of the desorption tank is connected to the air inlet of the separation tank;

[0025] The acetylene desorption process is carried out in a desorption tank, wherein the acetylene and a portion of the solvent enter the separation tank from the desorption tank and contact the filter membrane at the first side corresponding to the filter membrane;

[0026] The filter membrane allows the acetylene to pass through and transfer to a second side of the filter membrane; and

[0027] The filter membrane blocks a portion of the solvent, and the portion of the solvent falls back from the air inlet to the desorption tank due to gravity.

[0028] In one or more embodiments of the present invention, the acetylene and a portion of the solvent are introduced into the separation tank from the desorption tank at a gas flow rate of 2-6 SLM under a pressure of 0.05-0.4 MPa and a temperature of 22-28°C.

[0029] Compared with the prior art, the embodiments of the present invention provide an electronic-grade acetylene desorption and separation system and method. The desorption and separation system includes a desorption tank, a separation tank, a filter membrane, and an acetylene cylinder. The desorption tank has an outlet at its top. The separation tank is positioned above the desorption tank and has an inlet and an outlet opposite to each other. The inlet of the separation tank is connected to the outlet of the desorption tank, and the outlet is located above the inlet. The filter membrane is installed in the separation tank and has a first side and a second side opposite to each other. The first side is connected to the inlet, and the second side is connected to the outlet. The outlet of the separation tank is connected to the acetylene cylinder. The filter membrane is a polytetrafluoroethylene (PTFE) filter membrane, a cross-linked polyvinylidene fluoride (PVDF) filter membrane, a polyphenylene sulfide (PPS) filter membrane, or a polypropylene (PP) filter membrane. Thus, the acetylene desorbed from the desorption tank and some of the solvent carried out can be separated by the filter membrane. The filter membrane is corrosion resistant and is protected from solvent corrosion. In addition, the filter membrane is hydrophobic, which has the advantages of high-efficiency filtration and cost reduction. Furthermore, the solvent can fall back to the desorption tank from the air inlet by gravity without the need for additional power, thus achieving efficient solvent recovery. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the structure of an electronic-grade acetylene desorption and separation device according to an embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of the assembly structure of an electronic-grade acetylene desorption and separation system in one embodiment of the present invention;

[0033] Figure 3 This is a chromatogram of the detection at the air inlet in the first embodiment of the present invention;

[0034] Figure 4 This is a chromatogram of the gas outlet in the first embodiment of the present invention;

[0035] Figure 5 This is a chromatogram of the purity detection of the recovered solvent in the first embodiment of the present invention;

[0036] Figure 6 This is a chromatogram of the detection at the air inlet in the second embodiment of the present invention;

[0037] Figure 7 This is a chromatogram of the gas outlet in the second embodiment of the present invention;

[0038] Figure 8 This is a chromatogram for detecting the purity of the recovered solvent in the second embodiment of the present invention.

[0039] Explanation of key figure labels:

[0040] 1-Desorption and separation device, 11-Separation tank, 11a-First part, 11b-Second part, 111-Inlet, 112-Outlet, 12-Filter membrane, 121-Connection port, 13-Sealing gasket, 14-Elastic limiting element, 15-Purge and replacement port, 16-Solvent drain port, 2-Desorption tank, 21-Discharge port, 3-Acetylene cylinder, 4-Compressor, G-Gravity direction. Detailed Implementation

[0041] To enable those skilled in the art to better understand the technical solutions in this disclosure, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this disclosure.

[0042] Please see Figure 1 and Figure 2 , Figure 1 This is a schematic diagram of the structure of the electronic-grade acetylene desorption and separation device 1 in one embodiment of the present invention. Figure 2 This is a schematic diagram of the assembly structure of an electronic-grade acetylene desorption and separation system according to an embodiment of the present invention. Figure 2 As shown, the electronic-grade acetylene desorption system provided in the embodiments of the present invention includes a desorption tank 2, a desorption separation device 1, and an acetylene cylinder 3. The desorption tank 2 has an outlet 21 at its top. The separation tank 11 of the desorption separation device 1 is disposed above the desorption tank 2, and the inlet 111 of the separation tank 11 is connected to the outlet 21 of the desorption tank 2. The outlet 112 of the separation tank 11 is also connected to the acetylene cylinder 3.

[0043] like Figure 1 As shown, the desorption separation device 1 includes a separation tank 11 and a filter membrane 12. Figure 1 and Figure 2As shown, the separation tank 11 has an air inlet 111 and an air outlet 112 arranged opposite to each other. The air outlet 112 is located above the air inlet 111. The air inlet 111 is used to connect with the discharge outlet 21 of the desorption tank 2 so that the acetylene that escapes from the desorption tank 2 after desorption sequentially enters the separation tank 11 through the discharge outlet 21 and the air inlet 111. Figure 2 The purification device at the front end of the desorption tank 2 is well known to those skilled in the art and is therefore omitted. In this embodiment, the inlet 111 and the outlet 21 are connected by a flanged connection structure to ensure sealing, but this is not a limitation. It should be noted that the desorption tank 2 in this embodiment is used to perform a desorption process (e.g., reduced pressure, flash evaporation, etc.) on solvents (e.g., DMF, acetone, etc.) that have absorbed acetylene, so that the acetylene escapes from the solvent. At this time, part of the solvent mixes with the acetylene gas in the form of aerosol (liquid phase droplets) and enters the separation tank 11 together. The filter membrane 12 is installed inside the separation tank 11. The first side of the filter membrane 12 is connected to the inlet 111, and the second side of the filter membrane 12 is connected to the outlet 112. Acetylene on the first side of the filter membrane 12 can pass through the pores of the filter membrane 12 and transfer to the second side of the filter membrane 12, while the solvent is blocked by the filter membrane 12 on the first side. The filter membrane 12 is made of polytetrafluoroethylene (PTFE), cross-linked polyvinylidene fluoride (PVDF), polyphenylene sulfide (PPS), or polypropylene (PP), making it a corrosion-resistant and hydrophobic filter membrane. In this embodiment, the filter membrane 12 is purchased from Hangzhou Kebote Filter Material Co., Ltd. Taking PTFE filter membrane 12 as an example, the purchased PTFE filter membrane 12 models include CHTX20010TC10KMD and CHTX2NM50TC10KMD. The difference between the two models of PTFE filter membrane 12 lies in the pore size. It should be noted that those skilled in the art, upon learning the specific models of the PTFE filter membrane 12, can purchase the corresponding models of PVDF, PPS, and PP filter membranes sold by Hangzhou Kebote Filter Material Co., Ltd., or purchase similar filter membranes from other companies, depending on their actual needs. The actual application is not limited to this.

[0044] It should be noted that the "corrosion resistance" of the "corrosion-resistant hydrophobic filter membrane 12" specifically refers to the filter membrane 12 having strong chemical inertness and being difficult to react chemically with solvents. In other words, the filter membrane 12 will not change its shape or properties upon contact with solvents. Thus, when solvents come into contact with the corrosion-resistant hydrophobic filter membrane 12, corrosion of the filter membrane 12 can be avoided, thereby preventing swelling of the filter membrane 12 and problems such as pore blockage. The blocked solvent can then fall back into the desorption tank 2 through the air inlet 111 and outlet 21 by gravity, achieving solvent recycling. The desorption separation device 1 can achieve solvent return without the need for an additional power supply device, further reducing production costs.

[0045] In a preferred embodiment, the desorption separation device 1 is positioned with the inlet 111 and outlet 112 arranged in the direction of gravity G. In other embodiments, the relative orientation of the inlet 111 and outlet 112 may be slightly tilted relative to the direction of gravity G. However, practical applications are not limited to this.

[0046] In a preferred embodiment, the filter membrane 12 has multiple pores (not shown in the figure), wherein the pore size of the multiple pores is between 0.01 μm and 0.1 μm, and the porosity of the filter membrane 12 is between 70% and 80%, and the gas permeability resistance of the filter membrane 12 is less than or equal to 5 kPa. That is, the filter membrane 12 provided in this embodiment can ensure that acetylene gas passes through its pores with low resistance, thereby improving the extraction efficiency of acetylene. In a preferred embodiment, the contact angle between DMF and acetone and the filter membrane 12 is greater than or equal to 95 degrees, that is, the filter membrane 12 provided in this embodiment can ensure that the solvent is effectively blocked by the filter membrane 12, thereby facilitating the full separation of acetylene and solvent; and it can also reduce the contact area between the solvent and the filter membrane 12, thereby reducing the negative impacts of solvent on the filter membrane 12, such as corrosion and clogging.

[0047] Preferably, the preferred material for the filter membrane 12 is PTFE or PVDF, which have stronger hydrophobic properties than PP and PPS. When using PTFE or PVDF filter membrane 12, the contact angle between DMF and acetone can reach greater than or equal to 150 degrees, further improving the separation effect of acetylene gas and solvent.

[0048] In a preferred embodiment, such as Figure 1As shown, the filter membrane 12 forms a cylindrical structure. A first side of the filter membrane 12 is located inside the cylindrical structure, and a second side of the filter membrane 12 is located outside the cylindrical structure. The first end of the cylindrical structure is an open end and has a connection port 121. The inner side of the cylindrical structure is connected to the air inlet 111 via the connection port 121. In other embodiments, the filter membrane 12 may also be a planar structure extending in a plane perpendicular or substantially perpendicular to the relative directions of the air inlet 111 and the air outlet 112, thereby blocking the air inlet 111 and the air outlet 112. However, practical applications are not limited to this.

[0049] In a preferred embodiment, the desorption separation device 1 further includes a sealing gasket 13, which is disposed between the connection port 121 and the air inlet 111 to block the inner and outer sides of the cylindrical structure (i.e., the first and second sides of the filter membrane 12), preventing acetylene and solvent from leaking through the connection between the connection port 121 and the air inlet 111. The sealing gasket 13 is a perfluoroether sealing gasket 13 or a fluoropolymer-coated sealing gasket 13, making it a corrosion-resistant sealing gasket 13. In other words, the filter membrane 12 forms a sealed space (i.e., the inner side of the cylindrical structure), which is only connected to the air inlet 111 through the connection port 121, ensuring the sealing effect of the sealed space. The corrosion-resistant sealing gasket 13 disposed between the connection port 121 and the air inlet 111 prevents the solvent from corroding the sealing gasket 13 and affecting the sealing performance of the sealed space.

[0050] Preferably, the second end of the cylindrical structure is a closed end and is opposite to the first end. The desorption separation device 1 further includes an elastic limiting member 14, which is disposed between the inner wall of the separation tank 11 and the second end. The elastic force generated by the elastic limiting member 14 corresponds to the axial direction of the cylindrical structure, providing a constant axial fastening force for connecting the connection port 121 of the auxiliary filter membrane 12 to the air inlet 111 of the separation tank 11, ensuring a firm fixation and good sealing between the connection port 121 and the air inlet 111. Preferably, the elastic limiting member 14 can be one or more spring pressure rings. In some embodiments, the elastic limiting member 14 is replaceable and has various elastic specifications. Operators can select a suitable elastic limiting member 14 according to the size of the separation tank 11 or the filter membrane 12 to ensure appropriate fastening force and improve the versatility of the desorption separation device 1.

[0051] In a preferred embodiment, the separation tank 11 further includes a purge-displacement port 15, which is positioned corresponding to the second side of the filter membrane 12. After the filter membrane 12 is installed in the separation tank 11, an inert gas can be introduced into the separation tank through the purge-displacement port 15 to perform a purge-displacement operation, thereby removing moisture and / or impurity gases from the separation tank 11 and ensuring that the acetylene entering the separation tank 11 is not subject to secondary contamination during the separation process. In this embodiment, the purge-displacement operation is performed 10 to 30 times, but is not limited thereto. Preferably, the inert gas is helium; in other embodiments, the inert gas may also be neon, argon, krypton, or xenon, etc., but the actual application is not limited to these.

[0052] Preferably, pressure sensors (not shown in the figure) are respectively provided at the air inlet 111 and the air outlet 112 to detect the pressure difference between the air inlet 111 and the air outlet 112. If the pressure difference between the air inlet 111 and the air outlet 112 exceeds a first threshold, it can be determined that the pores of the filter membrane 12 are blocked. In this case, the inert gas can be introduced into the separation tank through the purge and replacement port 15 to remove the blockage (e.g., solvent) in the pores of the filter membrane 12, thereby improving the service life of the filter membrane 12 and the extraction of acetylene. In other preferred embodiments, such as... Figure 1 As shown, the separation tank 11 includes a detachably connected first part 11a and a second part 11b. The first part 11a is provided with an air inlet 111, and the second part 11b is provided with an air outlet 112. When the air pressure difference between the air inlet 111 and the air outlet 112 exceeds a first threshold, the first part 11a and the second part 11b are disassembled to replace the filter membrane 12. In this embodiment, the first part 11a and the second part 11b can be fixed by screws, or they can be fixed by snaps or other means. A sealing gasket (not shown in the figure) can be added at the junction of the first part 11a and the second part 11b. The sealing gasket and the sealing washer 13 can be made of the same material, which will not be described in detail.

[0053] In a preferred embodiment, the separation tank 11 further includes a solvent drain port 16, which is positioned corresponding to the second side of the filter membrane 12. By opening the solvent drain port 16, residual solvent that has permeated between the second side of the filter membrane 12 and the outlet 112 can be drained, further improving the reliability of the desorption separation device 1 and the solvent recovery rate. It should be noted that during the use of the desorption separation device 1, the inlet 111 is the lowest point of the separation tank 11 to ensure that the solvent can fall back into the desorption tank 2 under gravity. In this embodiment, the solvent drain port 16 is positioned adjacent to the inlet 111 as the second lowest point of the separation tank 11 (or the lowest point of the second side of the filter membrane 12). In other embodiments, the solvent drain port 16 may also be located at other positions in the separation tank 11, and the solvent drain port 16 may be connected to a liquid pump so that the solvent between the second side of the filter membrane 12 and the air outlet 112 is discharged from the solvent drain port 16 by the negative pressure provided by the liquid pump. However, the actual application is not limited to this.

[0054] In a preferred embodiment, such as Figure 2 As shown, the outlet 112 of the separator 11 is connected to the acetylene cylinder 3 to collect purified electronic-grade acetylene. In this embodiment, the outlet 112 and the acetylene cylinder 3 are connected by a flanged connection structure to ensure sealing, but this is not a limitation. In this embodiment, a compressor 4 is provided between the outlet 112 and the acetylene cylinder 3 to provide negative pressure to guide the acetylene gas from the separator 11 to the acetylene cylinder 3; however, practical applications are not limited to this.

[0055] Based on the above, the first embodiment of the present invention is used as an example to illustrate the desorption and separation method of electronic-grade acetylene and its effect. The filter membrane 12 is a PTFE filter membrane 12 purchased from Hangzhou Kebote Filter Material Co., Ltd., with a pore size of 0.05 μm (i.e., the model of the PTFE filter membrane 12 is CHTX2NM50TC10KMD), a porosity of 75%, and a DMF contact angle of 152 degrees. The steps for the desorption and separation of acetylene are as follows:

[0056] Step 1: Install the desorption separation device 1 directly above the desorption tank 2 via the flange connection structure of the air inlet 111. Insert the cylindrical PTFE filter membrane 12 into the separation tank 11. Adjust the elastic limiting member 14 to adjust the fastening force between the filter membrane 12 and the separation tank 11, ensuring that the filter membrane 12 is firmly fixed and has good sealing performance. The sealing gasket 13 is a perfluoroether sealing gasket 13. After the filter membrane 12 is installed, introduce helium gas into the separation tank 11 through the purge and replacement port 15 to purge and replace the inside of the separation tank 11 20 times to remove moisture and / or impurity gases inside the separation tank 11.

[0057] Step 2: The acetylene desorption process is carried out in the desorption tank 2. At a temperature of 25°C and a pressure of 0.2 MPa, the material discharged from the desorption tank 2 (containing 4N pure electronic grade acetylene and DMF solvent aerosol) is introduced from bottom to top into the inner side of the cylindrical filter membrane 12 (i.e., contacting the filter membrane 12 at the first side corresponding to the filter membrane 12) through the air inlet 111 to achieve natural dispersion.

[0058] Step 3: The material passes through the pores of the filter membrane 12 from the inside out. Utilizing the pore size screening effect and hydrophobic properties of the PTFE filter membrane 12, the DMF solvent aerosol is blocked on the first side of the filter membrane 12, while the pure electronic grade acetylene passes through the filter membrane 12 and enters the second side of the filter membrane 12, and is transferred to the outlet 112.

[0059] Step 4: The liquid DMF blocked on the first side of the filter membrane 12 flows downward along the inner wall of the filter membrane 12 under the action of gravity, and flows back to the desorption tank 2 through the air inlet 111 under the action of gravity, realizing the recycling of the solvent without the need for additional power and flow control valve.

[0060] Step 5: The separated pure electronic-grade acetylene is discharged through the outlet 112 to the subsequent purification process (e.g., stored in the acetylene cylinder 3). Pressure sensors installed at the inlet 111 and outlet 112 respectively monitor the pressure difference between the inlet 111 and outlet 112 in real time to ensure the stable operation of the desorption separation device 1.

[0061] After the above-mentioned desorption separation device 1 has been running continuously for 72 hours, if Figures 3 to 5 The test results showed that: Figure 3 It can be seen from the data that the concentration of DMF in the acetylene at the inlet is 4568.67 ppm. Figure 4 The concentration of solvent in the acetylene outlet 112 is 4.23 ppm, and the solvent interception efficiency can be calculated to be 99.91%. Figure 5 It can be seen that the purity of the recovered solvent is 99.78%, which can be directly reused; the flow meter at the back end is free from blockage and liquid accumulation, the pressure difference between the inlet 111 and the outlet 112 is small and stable, and the desorption separation device 1 operates stably.

[0062] Taking another second embodiment of the present invention as an example, the similarities between this second embodiment and the first embodiment will not be repeated here. The difference is that the filter membrane 12 in this second embodiment is a PVDF filter membrane 12 purchased from Hangzhou Kebote Filter Material Co., Ltd. The pore size of the filter membrane 12 is 0.03μm and the porosity is 78%. The DMF has a contact angle of 150 degrees. The material discharged from the desorption tank 2 contains 4N purity electronic grade acetylene and DMF solvent aerosol. The pipe diameter of the air inlet 111 is increased by 8mm compared with the pipe diameter configured when using DMF solvent to avoid solvent retention. The elastic limiting member 14 is adjusted accordingly.

[0063] After the above-mentioned desorption separation device 1 has been running continuously for 72 hours, if Figures 6 to 8 The test results showed that: Figure 6 It can be seen from the data that the concentration of DMF in the acetylene at the inlet is 4131.79 ppm. Figure 7 It can be seen from the data that the solvent concentration in the acetylene outlet 112 is 7.82 ppm, and the solvent interception efficiency can be calculated to be 99.81%. Figure 8 It can be seen that the purity of the recovered solvent is 99.26%, which can be directly reused; the flow meter at the back end is free from blockage and liquid accumulation, the pressure difference between the inlet 111 and the outlet 112 is small and stable, and the desorption separation device 1 operates stably.

[0064] Compared with the existing technology that uses a condenser phase change method to separate acetylene and solvent, under the same conditions, after 72 hours of operation using the condenser phase change method, the detection results show that the residual solvent content in the acetylene gas at outlet 112 is approximately 200 ppm to 300 ppm, with a solvent interception efficiency of approximately 70% to 80%. Significant liquid accumulation and large metering fluctuations occur in the downstream gas flow meter, requiring frequent liquid drainage and maintenance, which affects production continuity. Therefore, the embodiments of this invention can effectively reduce the residual solvent content in acetylene gas and improve the production efficiency of acetylene purification.

[0065] In summary, the electronic-grade acetylene desorption and separation system and method provided by the embodiments of the present invention include a desorption tank, a separation tank, a filter membrane, and an acetylene cylinder. The desorption tank has an outlet at its top. The separation tank is positioned above the desorption tank and has an inlet and an outlet opposite to each other. The inlet of the separation tank is connected to the outlet of the desorption tank, and the outlet is located above the inlet. The filter membrane is installed inside the separation tank and has a first side and a second side opposite to each other. The first side is connected to the inlet, and the second side is connected to the outlet. The outlet of the separation tank is connected to the acetylene cylinder. The filter membrane is a polytetrafluoroethylene (PTFE) filter membrane, a cross-linked polyvinylidene fluoride (PVDF) filter membrane, a polyphenylene sulfide (PPS) filter membrane, or a polypropylene (PP) filter membrane. Thus, the acetylene desorbed from the desorption tank and some of the solvent carried out can be separated by the filter membrane. The filter membrane is corrosion resistant and is protected from solvent corrosion. In addition, the filter membrane is hydrophobic, which has the advantages of high-efficiency filtration and cost reduction. Furthermore, the solvent can fall back to the desorption tank from the air inlet by gravity without the need for additional power, thus achieving efficient solvent recovery.

[0066] It will be apparent to those skilled in the art that this disclosure is not limited to the details of the exemplary embodiments described above, and that this disclosure can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of this disclosure is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this disclosure. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0067] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A desorption and separation system for electronic-grade acetylene, characterized in that, include: A desorption vessel, wherein the desorption vessel has a discharge port at its top; A separation tank is disposed above the desorption tank. The separation tank has an air inlet and an air outlet arranged opposite to each other. The air inlet of the separation tank is connected to the outlet of the desorption tank, and the air outlet is located above the air inlet. A filter membrane is installed inside the separation tank. The filter membrane has a first side and a second side opposite to each other. The first side is connected to the air inlet, and the second side is connected to the air outlet. An acetylene gas cylinder, wherein the outlet of the separation tank is connected to the acetylene gas cylinder; The filter membrane is a polytetrafluoroethylene (PTFE) filter membrane, a cross-linked polyvinylidene fluoride (PVDF) filter membrane, a polyphenylene sulfide (PPS) filter membrane, or a polypropylene (PP) filter membrane.

2. The desorption separation system as described in claim 1, characterized in that, The filter membrane has multiple pores, wherein the pore size is between 0.01 μm and 0.1 μm, and the porosity of the filter membrane is between 70% and 80%, and the air permeability resistance of the filter membrane is less than or equal to 5 kPa; and / or, The contact angle of N,N-dimethylformamide (DMF) and acetone with the filter membrane is greater than or equal to 95 degrees.

3. The desorption separation system as described in claim 1, characterized in that, The filter membrane forms a cylindrical structure, with a first side of the filter membrane located inside the cylindrical structure and a second side of the filter membrane located outside the cylindrical structure. The first end of the cylindrical structure is an open end and has a connection port, and the inner side of the cylindrical structure is connected to the air inlet through the connection port.

4. The desorption separation system as described in claim 3, characterized in that, It also includes a sealing gasket, which is disposed between the connection port and the air inlet, wherein the sealing gasket is a perfluoroether sealing gasket or a fluoropolymer-coated sealing gasket.

5. The desorption separation system as described in claim 3, characterized in that, The second end of the cylindrical structure is a closed end and is opposite to the first end; and The desorption separation system further includes an elastic limiting member disposed between the inner wall of the separation tank and the second end; wherein the elastic force generated by the elastic limiting member corresponds to the axial direction of the cylindrical structure.

6. The desorption separation system as described in claim 1, characterized in that, The separation tank also includes a purge and replacement port, which is located on the second side of the filter membrane.

7. The desorption separation system as described in claim 1, characterized in that, Pressure sensors are respectively installed at the air inlet and the air outlet.

8. The desorption separation system as described in claim 1, characterized in that, The separation tank includes a first part and a second part that are detachably connected. The first part is provided with the air inlet, and the second part is provided with the air outlet.

9. The desorption separation system as described in claim 1, characterized in that, The separation tank also includes a solvent drain port, which is positioned on the second side of the filter membrane.

10. A method for desorption and separation of electronic-grade acetylene, characterized in that, include: The separation tank of the desorption separation system as described in any one of claims 1 to 9 is disposed above the desorption tank, and the outlet of the desorption tank is connected to the air inlet of the separation tank; The acetylene desorption process is carried out in a desorption tank, wherein the acetylene and a portion of the solvent enter the separation tank from the desorption tank and contact the filter membrane at the first side corresponding to the filter membrane; The filter membrane allows the acetylene to pass through and transfer to a second side of the filter membrane; and The filter membrane blocks a portion of the solvent, and the portion of the solvent falls back from the air inlet to the desorption tank due to gravity.

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