A microchannel reactor and its application

Abstract

The present application relates to a microchannel reactor, the microchannel reactor comprises a mixing unit and a flow unit, the mixing unit and the flow unit are interconnected, the mixing unit comprises an air inlet pipe and a mixing tube, one port of the mixing tube is connected to the flow unit, the other port of the mixing tube is used for liquid inlet, the air inlet pipe is connected to the mixing tube and the air inlet pipe is arranged on the outer side wall of the mixing tube; a protrusion is arranged on the inner side wall of the mixing tube, the protrusion faces the port for liquid inlet of the mixing tube, and a concave spiral structure is arranged on the inner side wall of the flow unit; the inner diameter of the mixing tube is 1-3mm, the length of the mixing tube is 1-5cm, the inner diameter of the flow unit is 0.1-1mm, the length of the flow unit is 5-15cm, the ratio of the length of the mixing tube to the length of the flow unit is 1:3-5, and the ratio of the inner diameter of the mixing tube to the inner diameter of the flow unit is 3-10:1. The present application also relates to the application of the above-mentioned microchannel reactor in absorbing gas in ionic liquid.

Description

[Technical field]

[0001] The present application relates to the field of gas separation and process intensification, and specifically to a microchannel reactor, and the application of the microchannel reactor in energy gas separation and recovery, and microbubble flow mass transfer intensification. [Background technology]

[0002] This section provides background information related to the present application which does not necessarily constitute prior art.

[0003] Room temperature ionic liquids (RTILs) are salts composed of organic cations and organic or inorganic anions, and are in liquid form at room temperature and its vicinity, hereinafter referred to as ionic liquids. Ionic liquids have excellent properties such as low melting point, low vapor pressure, wide electrochemical stable potential window, good solubility characteristics, and can adjust their physical and chemical properties according to the changes of anions and cations. Ionic liquids have a rich hydrogen bond network structure that allows them to efficiently capture gas molecules and show great industrial application value in the field of gas separation. In addition, by utilizing the non-volatile characteristics of ionic liquids, the absorbed and captured gas can be desorbed at a lower energy through process design, thereby reducing the cost in the gas separation and recovery process, and the ionic liquids that absorb gas molecules can be recycled after desorption. However, in practical applications, due to the high viscosity and poor fluidity of ionic liquids, the gas / liquid mass transfer efficiency is low in traditional reactors, limiting industrial applications. Therefore, it is urgent to develop a new type of equipment and technology to efficiently enhance the flow and mass transfer process of ionic liquids.

[0004] A microchannel reactor is a miniaturized reaction system with a channel size in the millimeter range. Its large specific surface area and short transmission path enhance heat and mass transfer. The mass transfer coefficient of a microchannel reactor is increased by 1-3 orders of magnitude compared to conventional reactors. Therefore, it is expected to improve the flow mass transfer efficiency of the ionic liquid gas absorption process. [Summary of the invention]

[0005] The present application aims to provide a microchannel reactor that can be used to enhance the absorption of gas by ionic liquids. Based on the characteristic that the viscosity of ionic liquids decreases after absorbing gas, the microchannel reactor is applied to the process of ionic liquid absorption and separation of gas, which can enhance gas-liquid flow and mass transfer, and improve the gas absorption and separation efficiency by controlling parameters such as microchannel structure, fluid flow rate, and gas-liquid ratio.

[0006] The specific implementation plan of this application is as follows:

[0007] The microchannel reactor provided by the present application includes a mixing unit and a flow unit, the mixing unit and the flow unit are interconnected, the mixing unit includes an air inlet pipe and a mixing pipe, one port of the mixing pipe is connected to the flow unit, the other port of the mixing pipe is used for liquid inlet, the air inlet pipe is connected to the mixing pipe and the air inlet pipe is arranged on the outer side wall of the mixing pipe. The ionic liquid is continuously fed from the port of the mixing pipe of the mixing unit away from the flow unit, and the air inlet pipe of the mixing unit is used to input gas into the mixing pipe, so the feeding mode of the microchannel reactor is separate feeding of gas and liquid.

[0008] Preferably, the number of the air inlet pipes is 2-10, for example, 2, 3, 4, 7 or 10, but is not limited to the listed values, and other values ​​not listed in the numerical range are also applicable, preferably 2-4. By providing multiple air inlet pipes, multi-channel gas input can be achieved, thereby improving gas input efficiency.

[0009] The inner wall of the mixing tube is provided with a protrusion, which faces the liquid inlet port of the mixing tube. The protrusion is provided to increase the turbulence of the fluid and enhance mass transfer. The inner wall of the flow unit is provided with a concave spiral structure to enhance gas-liquid flow.

[0010] In one or more embodiments, needle-shaped protrusions are distributed on the inner wall of the mixing tube, the needle-shaped protrusions face the liquid inlet port of the mixing tube and form an angle of 30°-90° with the vertical direction, and the height of the needle-shaped protrusions is 100-1000 μm.

[0011] The inner diameter of the mixing tube is 1-3mm, for example, 1mm, 2mm or 3mm, but not limited to the listed values, and other values ​​not listed in the numerical range are also applicable; the length of the mixing tube is 1-5cm, for example, 1cm, 2cm, 3cm, 4cm or 5cm, but not limited to the listed values, and other values ​​not listed in the numerical range are also applicable. The inner diameter of the flow unit is 0.1-1mm, for example, 0.1mm, 0.4mm, 0.6mm, 0.8mm or 1mm, but not limited to the listed values, and other values ​​not listed in the numerical range are also applicable; the length of the flow unit is 5-15cm, for example, 5cm, 8cm, 10cm, 12cm or 15cm, but not limited to the listed values, and other values ​​not listed in the numerical range are also applicable.

[0012] Since the inner wall of the mixing tube is provided with a protrusion and the inner wall of the flow unit is provided with a concave spiral structure, this is conducive to the full contact between the gas and liquid phases in the microchannel reactor, but at the same time it will reduce the flow rate of the liquid phase in the microchannel reactor, resulting in the extension of the time of the gas and liquid in the microchannel reactor, resulting in reduced efficiency. Therefore, by setting the inner diameter of the flow unit to be not larger than the inner diameter of the mixing tube and the length of the flow unit to be not less than the length of the mixing tube, it can be achieved that: the viscosity of the ionic liquid decreases after absorbing the gas, and the ionic liquid after absorbing the gas can significantly increase the flow rate during the process of flowing from the mixing tube to the flow unit, thereby improving the gas absorption and separation efficiency. And it was unexpectedly found that based on the characteristic that the viscosity of the ionic liquid decreases after absorbing the gas, if any of the parameters of the inner diameter and length of the mixing tube and the inner diameter and length of the flow unit are not within the above range, the gas absorption and separation efficiency will be reduced.

[0013] In addition, the microchannel reactor provided in the present application satisfies the following conditions at the same time: (a) the ratio of the length of the mixing tube to the length of the flow unit is 1:3-5; (b) the ratio of the inner diameter of the mixing tube to the inner diameter of the flow unit is 3-10:1. It is unexpectedly found that if the microchannel reactor does not meet (a) and / or (b), the gas absorption and separation efficiency will be reduced.

[0014] The material of the microchannel reactor includes any one or a combination of at least two of stainless steel, inorganic non-metallic materials or polymers, and typical but non-limiting combinations include a combination of stainless steel and inorganic non-metallic materials, a combination of inorganic non-metallic materials and polymers, or a combination of stainless steel, inorganic non-metallic materials and polymers. Preferably, the stainless steel model includes 304 stainless steel and / or 316 stainless steel. Preferably, the inorganic non-metallic material includes any one or a combination of at least two of quartz, glass or silicon carbide, and typical but non-limiting combinations include a combination of quartz and glass, a combination of glass and silicon carbide, or a combination of quartz, glass and silicon carbide. Preferably, the polymer includes polytetrafluoroethylene.

[0015] In one or more embodiments, there is no filler inside the mixing unit and the flow unit, the cross-sections of the intake pipe, the mixing pipe and the flow unit are all circular, the mixing pipe and the flow unit are connected in series, and multiple intake pipes are connected to the mixing pipe in parallel.

[0016] The microchannel reactor provided in the present application can be used to enhance the absorption of gas by ionic liquid, specifically as follows: ionic liquid is used as an absorbent, and the microchannel reactor is used as a gas-liquid flow-mass transfer reactor. The ionic liquid is continuously fed from the port of the mixing tube of the mixing unit away from the flow unit, the air inlet pipe of the mixing unit is used to input gas into the mixing tube, the ionic liquid and the gas are respectively input into the mixing tube at a set speed, the gas and the ionic liquid flow in the same direction, the gas and liquid phases are fully in contact in the mixing tube, the gas is absorbed by the ionic liquid to obtain a mixed product, the mixed product flows into the flow unit from the mixing tube and then flows out from the end of the flow unit away from the mixing tube, the mixed product after flowing out is subjected to liquid-gas separation under heating or decompression conditions to remove the gas contained therein, and the ionic liquid can be recycled by desorption.

[0017] The flow rates of the ionic liquid and gas input into the mixing tube are controlled by the injection system. Preferably, the flow rate of the gas input into the mixing tube is 1-500 mL / h, the flow rate of the ionic liquid input into the mixing tube is 1-100 mL / h, and the gas-liquid ratio of the gas to the ionic liquid is 0.1-20:1. Before the gas is input into the mixing tube, the gas is dried so that the water content in the gas is less than 1000 ppm.

[0018] In one or more embodiments, the gas is one or more of NH3, CO2, Cl-VOCs, SO2, C2H4, C2H6, C3H6, and C3H8. The ionic liquid used has separation selectivity for the above gases, and the viscosity of the ionic liquid decreases by 10%-50% after absorbing the gas.

[0019] In one or more embodiments, the interior of the mixing tube of the microchannel reactor and the interior of the flow unit can be operated under pressurization, atmospheric pressure, and vacuum.

[0020] In one or more embodiments, the microchannel reactor can be heated and / or cooled. Depending on the heating and / or cooling requirements for the reaction and separation of the ionic liquid and gas, the heating and condensing medium can be air, steam, hot water, silicone oil, cold water or ethanol.

[0021] The present application also provides the application of the above microchannel reactor in ionic liquid absorption of gas. The microchannel reactor provided in the present application can be used as a reactor for enhancing ionic liquid absorption of gas, with relatively fast mass transfer and reaction time, which can greatly improve mass transfer efficiency.

[0022] The following describes the invention in conjunction with specific embodiments.

Brief Description of the Drawings

[0023] The accompanying drawings further illustrate the present application, but the embodiments in the accompanying drawings do not constitute any limitation to the present application.

[0024] Figure 1This is a schematic diagram of the structure of a microchannel reactor provided in one embodiment of the present application.

[0025] Among them, the figures are marked as: 10. intake pipe; 11. needle-shaped protrusion; 20. mixing tube; 30. flow tube. [Specific implementation method]

[0026] The technical scheme of the present application will be clearly and completely described below in conjunction with the embodiments. The described embodiments are only a part of the embodiments in the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by ordinary technicians in this field without paying creative work belong to the present application.

[0027] It should be noted that in the embodiments of the present application, the gas flow rate is controlled by a mass flow meter, the liquid flow rate is controlled by a microinjection pump, and the gas concentration and the absorption of the ionic liquid are analyzed by liquid chromatography, ion chromatography, gas chromatography, etc. The liquid side volume mass transfer coefficient is calculated according to the gas-liquid flow mass transfer law.

[0028] Example 1

[0029] like Figure 1 As shown, this embodiment provides a microchannel reactor, the material of the microchannel reactor is stainless steel, the microchannel reactor includes a mixing unit and a flow unit, the mixing unit and the flow unit are connected to each other, the mixing unit includes an air inlet pipe 10 and a mixing tube 20, the flow unit includes a flow tube 30, one end of the mixing tube 20 is connected to the flow tube 30, and the other end of the mixing tube 20 is used for liquid inlet, three air inlet pipes 10 are connected to the mixing tube 20, and the three air inlet pipes are all arranged on the outer side wall of the mixing tube 20. Needle-shaped protrusions 11 are distributed on the inner side wall of the mixing tube 20, and a concave spiral structure is arranged on the inner side wall of the flow tube 30.

[0030] The inner diameter of the flow tube 30 is 1 mm, the length of the flow tube 30 is 5 cm, the inner diameter of the mixing tube 20 is 3 mm, the length of the mixing tube 20 is 1 cm, the needle-shaped protrusion 11 forms an angle of 60° with the vertical direction, the needle-shaped protrusion 11 faces the liquid inlet port of the mixing tube 20, and the height of the needle-shaped protrusion 11 is 500 μm.

[0031] At room temperature and pressure, a microinjection pump and a gas flowmeter are used to drive the liquid phase (i.e., ionic liquid) and the gas phase into the mixing tube 20 of the microchannel reactor, respectively. The ionic liquid used is [Bmim][NO3], and the gas is pure ammonia. After the ionic liquid absorbs ammonia, the viscosity decreases by 30%. The flow rate of the ionic liquid input into the mixing tube 20 is 18 mL / h, and the flow rate of the gas input into the mixing tube 20 is 120 mL / h. During the gas-liquid flow process, the single gas removal efficiency is 99%, and the liquid side volume mass transfer coefficient (kLa) is calculated to be 0.22 s -1, which can significantly improve gas-liquid mass transfer.

[0032] Example 2

[0033] The present embodiment provides a microchannel reactor. The only difference between the microchannel reactor provided in the present embodiment and the microchannel reactor provided in Example 1 is that: in the microchannel reactor provided in the present embodiment, 10 air inlet pipes are connected to the mixing tube, and the 10 air inlet pipes are all arranged on the outer wall of the mixing tube; the inner diameter of the flow tube is 0.1 mm, and the length of the flow tube is 15 cm; the inner diameter of the mixing tube is 1 mm, and the length of the mixing tube is 5 cm; the height of the needle-shaped protrusion is 200 μm.

[0034] At room temperature and pressure, a microinjection pump and a gas flowmeter are used to drive the liquid phase (i.e., ionic liquid) and the gas phase into the mixing tube of the microchannel reactor. The ionic liquid used is [Bmim][NTF2], and the gas is composed of 50% ammonia and 50% nitrogen by volume. The viscosity of the ionic liquid decreases by 50% after absorbing the gas. The flow rate of the ionic liquid input into the mixing tube is 9 mL / h, and the flow rate of the gas input into the mixing tube is 100 mL / h. During the gas-liquid flow process, the single gas removal efficiency is 99%, and the liquid side volume mass transfer coefficient (kLa) is calculated to be 0.18s -1 , which can significantly improve gas-liquid mass transfer.

[0035] Example 3

[0036] The present embodiment provides a microchannel reactor. The only difference between the microchannel reactor provided in the present embodiment and the microchannel reactor provided in Example 1 is that: in the microchannel reactor provided in the present embodiment, the material of the microchannel reactor is PMMA; two air inlet pipes are connected to the mixing tube, and the two air inlet pipes are both arranged on the outer wall of the mixing tube; the inner diameter of the flow tube is 0.8 mm, and the length of the flow tube is 15 cm; the inner diameter of the mixing tube is 2.5 mm, and the length of the mixing tube is 4 cm; the height of the needle-shaped protrusion is 1000 μm.

[0037] At room temperature and pressure, a microinjection pump and a gas flowmeter are used to drive the liquid phase (i.e., ionic liquid) and the gas phase into the mixing tube of the microchannel reactor. The ionic liquid used is [Bmim][BF4], and the gas is composed of 50% by volume of ethane and 50% by volume of ethylene. The viscosity of the ionic liquid decreases by 10% after absorbing the gas. The flow rate of the ionic liquid input into the mixing tube is 18 mL / h, and the flow rate of the gas input into the mixing tube is 120 mL / h. During the gas-liquid flow process, the single gas removal efficiency is 99%, and the liquid side volume mass transfer coefficient (kLa) is calculated to be 0.45s -1 , which can significantly improve gas-liquid mass transfer.

[0038] Example 4

[0039] The present embodiment provides a microchannel reactor. The difference between the microchannel reactor provided in the present embodiment and the microchannel reactor provided in Example 1 is only that: in the microchannel reactor provided in the present embodiment, four air inlet pipes are connected to a mixing tube, and the four air inlet pipes are all arranged on the outer wall of the mixing tube; the inner diameter of the flow tube is 0.25 mm, and the length of the flow tube is 12 cm; the inner diameter of the mixing tube is 2 mm, and the length of the mixing tube is 3 cm.

[0040] At room temperature and pressure, a microinjection pump and a gas flowmeter are used to drive the liquid phase (i.e., ionic liquid) and the gas phase into the mixing tube of the microchannel reactor. The ionic liquid used is [Bmim][BF4], and the gas is composed of 50% propane and 50% propylene by volume. The viscosity of the ionic liquid decreases by 10% after absorbing the gas. The flow rate of the ionic liquid input into the mixing tube is 6 mL / h, and the flow rate of the gas input into the mixing tube is 120 mL / h. During the gas-liquid flow process, the single gas removal efficiency is 99%, and the liquid side volume mass transfer coefficient (kLa) is calculated to be 0.13s -1 , which can significantly improve gas-liquid mass transfer.

[0041] Example 5

[0042] The microchannel reactor provided in this embodiment is the same as the microchannel reactor provided in Example 4.

[0043] At room temperature and pressure, a microinjection pump and a gas flowmeter are used to drive the liquid phase (i.e., ionic liquid) and the gas phase into the mixing tube of the microchannel reactor. The ionic liquid used is [Bmim][BF4], and the gas is pure carbon dioxide. The viscosity of the ionic liquid decreases by 10% after absorbing carbon dioxide. The flow rate of the ionic liquid input into the mixing tube is 6 mL / h, and the flow rate of the gas input into the mixing tube is 240 mL / h. During the gas-liquid flow process, the single gas removal efficiency is 99%, and the liquid side volume mass transfer coefficient (kLa) is calculated to be 0.01s -1 , which can significantly improve gas-liquid mass transfer.

[0044] When the inner diameter of the mixing tube was changed to 3 mm and other conditions remained unchanged, the carbon dioxide removal rate was 92%.

[0045] When the inner diameter of the mixing tube was changed to 4 mm and other conditions remained unchanged, the carbon dioxide removal rate was 93%.

[0046] When the inner diameter of the mixing tube was changed to 0.8 mm and other conditions remained unchanged, the carbon dioxide removal rate was 83%.

[0047] When the length of the mixing tube was changed to 5 cm and other conditions remained unchanged, the carbon dioxide removal rate was 91%.

[0048] When the length of the mixing tube was changed to 2 cm and other conditions remained unchanged, the carbon dioxide removal rate was 89%.

[0049] When the length of the mixing tube was changed to 6 cm and other conditions remained unchanged, the carbon dioxide removal rate was 88%.

[0050] When the length of the mixing tube was changed to 0.8 cm and other conditions remained unchanged, the carbon dioxide removal rate was 81%.

[0051] Example 6

[0052] The microchannel reactor provided in this embodiment is the same as the microchannel reactor provided in Example 4.

[0053] At room temperature and pressure, a microinjection pump and a gas flowmeter are used to drive the liquid phase (i.e., ionic liquid) and the gas phase into the mixing tube of the microchannel reactor, respectively. The ionic liquid used is [Bmim][DCA], and the gas is dichloromethane. The viscosity of the ionic liquid decreases by 30% after absorbing dichloromethane. The flow rate of the ionic liquid input into the mixing tube is 12 mL / h, and the flow rate of the gas input into the mixing tube is 360 mL / h. During the gas-liquid flow process, the single gas removal efficiency is 99%, and the liquid side volume mass transfer coefficient (kLa) is calculated to be 0.41s -1 , which can significantly improve gas-liquid mass transfer.

[0054] The inner diameter of the flow tube was changed to 0.8 mm, and other conditions remained unchanged, and the removal rate of dichloromethane was 90%.

[0055] The inner diameter of the flow tube was changed to 0.1 mm, and other conditions remained unchanged, and the removal rate of dichloromethane was 92%.

[0056] The inner diameter of the flow tube was changed to 0.08 mm, and other conditions remained unchanged, and the removal rate of dichloromethane was 94%.

[0057] The inner diameter of the flow tube was changed to 1.5 mm, and other conditions remained unchanged, and the removal rate of dichloromethane was 87%.

[0058] Changing the length of the flow tube to 8 cm, while keeping other conditions unchanged, the removal rate of dichloromethane was 93%. Changing the length of the flow tube to 4 cm, while keeping other conditions unchanged, the removal rate of dichloromethane was 89%.

[0059] The length of the flow tube was changed to 16 cm, and other conditions remained unchanged, and the removal rate of dichloromethane was 91%.

[0060] Example 7

[0061] The microchannel reactor provided in this embodiment is the same as the microchannel reactor provided in Example 4.

[0062] At room temperature and pressure, a microinjection pump and a gas flowmeter are used to drive the liquid phase (i.e., ionic liquid) and the gas phase into the mixing tube of the microchannel reactor. The ionic liquid used is [Bmim][NTF2], and the gas is sulfur dioxide. After the ionic liquid absorbs sulfur dioxide, the viscosity decreases by 20%. The flow rate of the ionic liquid input into the mixing tube is 30 mL / h, and the flow rate of the gas input into the mixing tube is 120 mL / h. During the gas-liquid flow process, the single gas removal efficiency is 99%, and the liquid side volume mass transfer coefficient (kLa) is calculated to be 0.34s -1 , which can significantly improve gas-liquid mass transfer.

[0063] Changing the inner diameter of the mixing tube to 3 mm, with other conditions unchanged, the liquid side volumetric mass transfer coefficient of the reaction is 0.36s -1 .

[0064] Changing the inner diameter of the mixing tube to 4 mm, with other conditions unchanged, the liquid side volumetric mass transfer coefficient of the reaction is 0.39s -1 .

[0065] Changing the inner diameter of the mixing tube to 0.8 mm, with other conditions unchanged, the liquid side volume mass transfer coefficient of the reaction is 0.47s -1 .

[0066] Changing the length of the mixing tube to 6 cm, with other conditions unchanged, the liquid side volume mass transfer coefficient of the reaction is 3.8s -1 .

[0067] Changing the length of the mixing tube to 0.8 cm, with other conditions unchanged, the liquid side volume mass transfer coefficient of the reaction is 0.46s -1 .

[0068] Changing the inner diameter of the flow tube to 0.8 mm, with other conditions unchanged, the liquid side volumetric mass transfer coefficient of the reaction is 0.51s -1 .

[0069] Changing the inner diameter of the flow tube to 0.1 mm, with other conditions unchanged, the liquid side volumetric mass transfer coefficient of the reaction is 0.41s -1 .

[0070] Changing the inner diameter of the flow tube to 0.08 mm, with other conditions unchanged, the liquid side volumetric mass transfer coefficient of the reaction is 0.44s -1 . .

[0071] Changing the inner diameter of the flow tube to 1.5 mm, with other conditions unchanged, the liquid side volumetric mass transfer coefficient of the reaction is 0.58 s -1 .

[0072] Changing the length of the flow tube to 8 cm, with other conditions unchanged, the liquid side volumetric mass transfer coefficient of the reaction is 0.45s -1 .

[0073] Changing the length of the flow tube to 4 cm, with other conditions unchanged, the liquid side volumetric mass transfer coefficient of the reaction is 0.52s -1 .

[0074] Changing the length of the flow tube to 16 cm, with other conditions unchanged, the liquid side volumetric mass transfer coefficient of the reaction is 0.61s -1 .

[0075] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0076] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A microchannel reactor, characterized in that: The microchannel reactor comprises a mixing unit and a flow unit, the mixing unit and the flow unit are connected to each other, the mixing unit comprises an air inlet pipe and a mixing pipe, one end of the mixing pipe is connected to the flow unit, the other end of the mixing pipe is used for liquid inlet, the air inlet pipe is connected to the mixing pipe and the air inlet pipe is arranged on the outer side wall of the mixing pipe; A protrusion is provided on the inner side wall of the mixing tube, the protrusion faces the port for liquid inlet of the mixing tube, and a concave spiral structure is provided on the inner side wall of the flow unit; The inner diameter of the mixing tube is 1-3 mm, the length of the mixing tube is 1-5 cm, the inner diameter of the flow unit is 0.1-1 mm, the length of the flow unit is 5-15 cm, the ratio of the length of the mixing tube to the length of the flow unit is 1:3-5, and the ratio of the inner diameter of the mixing tube to the inner diameter of the flow unit is 3-10:

1.

2. The microchannel reactor according to claim 1, characterized in that: The number of the air inlet pipes is 2-10.

3. The microchannel reactor according to claim 1, characterized in that: The inner wall of the mixing tube is provided with needle-shaped protrusions, the needle-shaped protrusions form an angle of 30°-90° with the vertical direction, and the height of the needle-shaped protrusions is 100-1000 μm.

4. Use of the microchannel reactor according to any one of claims 1 to 3 in ionic liquid absorption of gas.

5. The use according to claim 4, characterized in that: The gas is one or more of NH3, CO2, SO2, C2H4, C2H6, C3H6, and C3H8.

6. The use according to claim 5, characterized in that: After the ionic liquid absorbs the gas, the viscosity decreases by 10%-50%.

7. The use according to claim 6, characterized in that: The flow rate of the gas input into the mixing tube is 1-500 mL / h, the flow rate of the ionic liquid input into the mixing tube is 1-100 mL / h, and the gas-liquid ratio of the gas to the ionic liquid is 0.1-20:1.

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