Gas separation membrane and method and system for removing oxygen in oxygen-containing organic gas

Abstract

The invention relates to the technical field of organic gas deoxidation, and discloses a gas separation membrane and a method and system for removing oxygen in oxygen-containing organic gas. The gas separation membrane comprises a high-molecular polymer and an inorganic matrix dispersed in the high-molecular polymer, the content of the inorganic matrix is 0.5-10 parts by weight relative to 100 parts by weight of the high-molecular polymer, the high-molecular polymer is modified or unmodified polysulfone resin, the inorganic matrix is nanoparticles, and the particle size is less than 500nm. The method for removing the oxygen in the oxygen-containing organic gas comprises the steps that the oxygen-containing organic gas is conveyed into a membrane separation device to be subjected to deoxidation treatment, and the gas separation membrane is arranged in the membrane separation device. When the gas separation membrane is used for deoxidizing the oxygen-containing organic gas, a better deoxidizing effect can be obtained.

Description

Technical Field

[0001] The present invention relates to the technical field of organic gas deoxygenation, and in particular to a gas separation membrane and a method and system for removing oxygen from oxygen-containing organic gas. Background Art

[0002] The oxidation process is an important process in the chemical production process, involving redox reactions. Oxygen, hydrogen peroxide, organic peroxides, etc. are common oxidants. Due to side reactions and low oxidant conversion rates, the oxidation process will produce oxygen-containing organic gases during the reaction, such as the HPPO propylene oxide unit producing oxygen-containing propylene gas. The presence of oxygen increases the risk of explosion in the system. At the same time, oxygen-containing tail gas cannot enter the flare system when the oxygen concentration is >2% by volume. Therefore, the treatment of this tail gas has become a problem worthy of attention.

[0003] There are many treatment methods for oxygen-containing organic tail gas, such as catalytic oxidation, adsorption, compression condensation, etc. Patent application CN109748888A discloses a method for removing oxygen from circulating gas in the HPPO process. By connecting the deoxygenation reactor to the circulating propylene compressor and the propylene buffer tank, the oxygen in the circulating gas can be successfully removed, and the safe and stable operation level of the device can be improved. Patent application CN103861422A discloses a new process method for concentrating methane in oxygen-containing inner layer gas. According to the different methane concentrations in the oxygen-containing coal bed gas, the methane concentration in the coal bed gas can be increased to >90% and the oxygen content can be reduced to <0.5% by using different adsorbents and processes. The effect is very excellent. Deep cold liquefaction separation technology is based on the difference in boiling points between oxygen and other gases in coal bed gas. First, the coal bed gas is condensed into liquid through compression and expansion refrigeration, and then the temperature is increased and distilled. The gas with a low boiling point is precipitated first, and finally the gas separation of each fraction is achieved to obtain a high-purity product gas. It is also an excellent oxygen-containing organic gas deoxygenation technology. Patent application CN1908559A discloses a process and equipment for liquefying and separating coalbed methane containing air, which can realize liquefaction and separation of coalbed methane containing air, and has convenient and simple operation and low investment cost.

[0004] In summary, there are currently a variety of methods for removing oxygen from oxygen-containing organic gases, and different methods are suitable for different deoxygenation scenarios. However, the existing deoxygenation technologies often have high energy consumption to achieve the transformation of materials from high entropy to low entropy. For example, catalyst deoxygenation requires a higher reaction temperature, the adsorption method requires the use of a large amount of adsorption materials and requires a higher adsorption pressure, and the compression condensation method consumes a lot of energy in the process of compressing and cooling the material. Summary of the invention

[0005] The purpose of the present invention is to provide a gas separation membrane and a method and system for removing oxygen from oxygen-containing organic gas. The gas separation membrane of the present invention can achieve a better oxygen removal effect, and the deoxygenation process can be achieved at a lower energy consumption and is simple to operate.

[0006] In order to achieve the above-mentioned purpose, the present invention provides a gas separation membrane on the one hand, which includes a polymer and an inorganic matrix dispersed in the polymer, and the content of the inorganic matrix is ​​0.5-10 parts by weight relative to 100 parts by weight of the polymer, wherein the polymer is a modified or unmodified polysulfone resin, and the inorganic matrix is ​​nanoparticles with a particle size of less than 500nm.

[0007] Preferably, the polymerization degree of the high molecular weight polymer is 5-100, preferably 30-80.

[0008] Preferably, the modified polysulfone resin is a polysulfone resin modified with nitric acid and / or a polysulfone resin modified with glycerol.

[0009] Preferably, the inorganic matrix is ​​at least one of molecular sieve, white carbon black, silica gel and alumina.

[0010] A second aspect of the present invention provides a method for removing oxygen from an oxygen-containing organic gas, the method comprising: transporting the oxygen-containing organic gas to a membrane separation device for deoxygenation treatment, wherein the membrane separation device is provided with the gas separation membrane described above.

[0011] Preferably, the oxygen-containing organic gas enters the membrane separation device after being dried, pressure-regulated and temperature-regulated.

[0012] Preferably, the temperature of the oxygen-containing organic gas entering the membrane separation device is 0-50° C. and the pressure is 0.2-1.5 MPaG through pressure regulation and temperature regulation.

[0013] Preferably, the oxygen-containing organic gas is at least one of the tail gas of the HPPO process propylene oxide, the tail gas of the hydrogen peroxide process epichlorohydrin and the tail gas of the ethylene process ethylene oxide.

[0014] A third aspect of the present invention provides a system for removing oxygen from an oxygen-containing organic gas, the system comprising:

[0015] A drying device, used for drying oxygen-containing organic gas;

[0016] A temperature regulating device, used for regulating the temperature of the oxygen-containing organic gas after drying;

[0017] A pressure regulating device, arranged on the connecting pipe between the drying device and the temperature regulating device, for regulating the pressure of the oxygen-containing organic gas;

[0018] A membrane separation device, used for deoxygenating the oxygen-containing organic gas from the temperature regulating device to obtain a permeate-side gas mainly containing oxygen and a deoxygenated retentate-side gas, wherein the membrane separation device is provided with the gas separation membrane described above;

[0019] The non-condensable gas separation tower is used to process the retentate side gas from the membrane separation device and separate the non-condensable gas from the gas phase.

[0020] Preferably, a first online oxygen content analyzer is provided at the air inlet of the drying device, a second online oxygen content analyzer is provided at the permeate side gas outlet of the membrane separation device, and a third online oxygen content analyzer is provided at the retentate side gas outlet of the membrane separation device.

[0021] According to the technical solution of the present invention, by uniformly dispersing the inorganic matrix of nanoparticles in the polysulfone resin, not only the mechanical properties of the gas separation membrane can be improved, but also the selective separation of oxygen and other organic gases can be achieved. Therefore, the gas separation membrane of the present invention can be used to remove oxygen from oxygen-containing organic gases (such as HPPO process propylene oxide process tail gas, hydrogen peroxide process epichlorohydrin process tail gas, ethylene process ethylene oxide process tail gas, etc.).

[0022] In the method and system for removing oxygen from oxygen-containing organic gas described in the present invention, by setting the gas separation membrane described in the present invention in a membrane separation device, and allowing the oxygen-containing organic gas to enter the membrane separation device for deoxygenation treatment after being dried and adjusted to appropriate temperature and pressure, a better deoxygenation effect can be obtained, and the deoxygenation process has low energy consumption and simple operation, which is conducive to industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the system for removing oxygen from oxygen-containing organic gas according to the present invention.

[0024] Description of Reference Numerals

[0025] 1. First online oxygen content analyzer; 2. Drying device; 3. Temperature regulating device; 4. Membrane separation device; 5. Third online oxygen content analyzer; 6. Second online oxygen content analyzer; 7. Vacuum pump; 8. Non-condensable gas separation tower; 9. Pressure regulating device. DETAILED DESCRIPTION

[0026] The specific embodiments of the present invention are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0027] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0028] In the description of this application, the terms "first", "second", and "third" are used for descriptive purposes only and should not be understood as indicating relative importance or implicitly indicating the number of technical features indicated. Therefore, unless otherwise specified, a feature defined as "first", "second", and "third" may explicitly or implicitly include one or more of the features. The term "comprising" and any variation thereof means non-exclusive inclusion, and one or more other features, integers, steps, operations, units, components, and / or combinations thereof may be present or added.

[0029] The gas separation membrane of the present invention comprises a high molecular polymer and an inorganic matrix dispersed in the high molecular polymer.

[0030] In the gas separation membrane described in the present invention, the content of the inorganic matrix is ​​0.5-10 parts by weight, preferably 1-8 parts by weight, relative to 100 parts by weight of the high molecular weight polymer. Specifically, for example, it can be 1 part by weight, 1.5 parts by weight, 2 parts by weight, 2.5 parts by weight, 3 parts by weight, 3.5 parts by weight, 4 parts by weight, 4.5 parts by weight, 5 parts by weight, 5.5 parts by weight, 6 parts by weight, 7 parts by weight or 8 parts by weight.

[0031] In the gas separation membrane of the present invention, the high molecular polymer is a modified or unmodified polysulfone resin. The degree of polymerization of the high molecular polymer may be 5-100, preferably 8-90, more preferably 20-85, and most preferably 30-80. The modified polysulfone resin is preferably a polysulfone resin modified by nitric acid and / or a polysulfone resin modified by glycerol.

[0032] In the gas separation membrane of the present invention, the inorganic matrix is ​​a nanoparticle with a particle size of 500 nm or less. In the present invention, the particle size refers to the maximum straight-line distance between any two different points on the particle. When the particle is spherical, the particle size refers to the diameter of the particle. Preferably, the particle size of the inorganic matrix is ​​1-300 nm, more preferably 5-100 nm. The particle morphology of the inorganic matrix can be flake or block, etc., and is most preferably flake.

[0033] In the gas separation membrane of the present invention, the inorganic matrix is ​​preferably at least one of molecular sieve, white carbon black, silica gel and alumina, and most preferably molecular sieve and / or white carbon black. In the present invention, the molecular sieve can be a conventional molecular sieve in the art, for example, S-1 molecular sieve, ZSM-5 molecular sieve, SSZ-13 molecular sieve, S-2 molecular sieve, SAPO-34 molecular sieve, etc.

[0034] In a more preferred embodiment, the inorganic matrix is ​​a mixture of molecular sieve and white carbon black, in particular a mixture of S-1 molecular sieve and white carbon black. Further preferably, in the inorganic matrix, the mass ratio of molecular sieve to white carbon black is 1-5:1, more preferably 2-3:1. According to the above preferred embodiment, the gas separation membrane can obtain a further improved deoxygenation effect.

[0035] In the present invention, when the high molecular polymer is polysulfone resin, the preparation method of the gas separation membrane comprises: dissolving the polysulfone resin in an organic solvent, then adding a sheet-like inorganic matrix and a dispersant, and then coating the obtained mixed slurry on a substrate.

[0036] In the present invention, when the high molecular polymer is a modified polysulfone resin, the preparation method of the gas separation membrane includes: modifying the polysulfone resin with a nitric acid solution or a glycerol solution, dissolving the obtained modified polysulfone resin in an organic solvent, then adding a flaky inorganic matrix and a dispersant, and then coating the obtained mixed slurry on a substrate.

[0037] In the above preparation method, the coating process is preferably carried out at 0-50°C.

[0038] In the above preparation method, the organic solvent may be at least one of dichloromethane, chloroform, dimethylformamide, N-methylpyrrolidone and acetone.

[0039] In the above preparation method, the dispersant may be at least one of ethylene glycol, polyethylene glycol, methyl amyl alcohol, and guar gum.

[0040] In the above preparation method, the substrate can be a porous alumina substrate (such as a hollow tube or a flat plate), a porous titanium oxide plate substrate or a glass plate substrate.

[0041] In the above preparation method, in order to obtain a better film-forming effect, the coating may be repeated on the substrate for several times, such as 3 to 10 times.

[0042] The method for removing oxygen from oxygen-containing organic gas of the present invention comprises: transporting the oxygen-containing organic gas to a membrane separation device for deoxygenation treatment, wherein the membrane separation device is provided with the gas separation membrane described above.

[0043] In the method for removing oxygen from oxygen-containing organic gas, in order to obtain a better deoxygenation effect, preferably, the oxygen-containing organic gas enters the membrane separation device after drying, pressure adjustment and temperature adjustment. Further preferably, the temperature of the oxygen-containing organic gas entering the membrane separation device is 0-50°C and the pressure is 0.2-1.5MPaG through pressure adjustment and temperature adjustment. In this article, MPaG refers to gauge pressure.

[0044] In the method for removing oxygen from oxygen-containing organic gas, the oxygen-containing organic gas can be a conventional oxygen-containing organic gas in the art. In some embodiments, the oxygen-containing organic gas is at least one of the tail gas of HPPO process propylene oxide, the tail gas of hydrogen peroxide process epichlorohydrin process and the tail gas of ethylene process ethylene oxide.

[0045] like Figure 1 As shown, the system for removing oxygen from oxygen-containing organic gas according to the present invention comprises:

[0046] A drying device 2, used for drying the oxygen-containing organic gas;

[0047] The temperature regulating device 3 is used to regulate the temperature of the oxygen-containing organic gas after the drying process;

[0048] The pressure regulating device 9 is arranged on the connecting pipe between the drying device 2 and the temperature regulating device 3, and is used to regulate the pressure of the oxygen-containing organic gas;

[0049] A membrane separation device 4, used for deoxygenating the oxygen-containing organic gas from the temperature adjustment device 3 to obtain a permeate side gas mainly containing oxygen and a deoxygenated retentate side gas, wherein the membrane separation device 4 is provided with the gas separation membrane described above;

[0050] The non-condensable gas separation tower 8 is used to process the retentate side gas from the membrane separation device 4 and separate the non-condensable gas from the gas phase.

[0051] In the system of the present invention, preferably, a first online oxygen content analyzer 1 is provided at the air inlet of the drying device 2 to detect the oxygen content in the initial oxygen-containing organic gas.

[0052] In the system of the present invention, preferably, a second online oxygen content analyzer 6 is provided at the permeate side gas outlet of the membrane separation device 4 to detect the oxygen content in the permeate side gas mainly containing oxygen. In addition, the permeate side gas is discharged through a vacuum pump 7.

[0053] In the system of the present invention, in a preferred case, a third online oxygen content analyzer 5 is provided at the retentate-side gas outlet of the membrane separation device 4 to measure the oxygen content in the retentate-side gas after deoxygenation.

[0054] In the system of the present invention, preferably, the temperature regulating device 3 and the pressure regulating device 9 are regulated according to the oxygen content of the retentate side gas, for example, when the oxygen content of the retentate side gas is high, the temperature and / or the pressure are lowered.

[0055] In the system described in the present invention, the drying method of the drying device 2 can be adsorption drying, and water vapor in the oxygen-containing organic gas is removed by adsorption drying.

[0056] In the system described in the present invention, the temperature regulating device 3 is mainly used to reduce the temperature of the incoming oxygen-containing organic gas to a certain temperature range. The temperature regulating device 3 can be a heat exchanger, which generally uses cooling water as a heat exchange medium to exchange heat with the oxygen-containing organic gas entering the heat exchanger, so as to reduce the temperature of the oxygen-containing organic gas to a certain temperature range.

[0057] In the system described in the present invention, the pressure regulating device 9 can be a pressure reducing valve or a booster pump. When the pressure of the incoming oxygen-containing organic gas is high, the pressure reducing valve is used to reduce the pressure and reduce the pressure of the oxygen-containing organic gas to a certain pressure range; when the pressure of the incoming oxygen-containing organic gas is low, the booster pump is used to increase the pressure and increase the pressure of the oxygen-containing organic gas to a certain pressure range.

[0058] In the system described in the present invention, a jacket structure is disposed on the periphery of the membrane separation device 4 , and cooling water is introduced into the jacket structure to cool the oxygen-containing organic gas entering the membrane separation device 4 .

[0059] In the system described in the present invention, the non-condensable gas separation tower 8 can be a distillation tower, and the retentate side gas from the membrane separation device 4 is subjected to gas-liquid separation in the distillation tower, the gas phase separates the non-condensable gas, and the liquid phase obtains the organic component (such as olefins).

[0060] The following examples further illustrate the gas separation membrane and the method and system for removing oxygen from oxygen-containing organic gas of the present invention. The examples are implemented based on the technical solution of the present invention, and detailed implementation methods and specific operation processes are given, but the protection scope of the present invention is not limited to the following examples.

[0061] The experimental methods in the following examples, unless otherwise specified, are all conventional methods in the art. The experimental materials used in the following examples, unless otherwise specified, are all commercially available.

[0062] Example 1

[0063] (1) Preparation of gas separation membrane

[0064] After 100g of polysulfone powder (average degree of polymerization of 55, purchased from Sinopharm Reagent Company) was dissolved in 350g of dichloromethane at 30°C, 1.5g of S-1 molecular sieve (flaky particles, particle size of 20-50nm) was added to the mixture, and 5g of polyethylene glycol (weight average molecular weight of 4000, purchased from Aladdin Company) was added to the mixed system under stirring. The obtained mixed slurry was then uniformly coated on a porous alumina hollow tube at 25°C and evaporated at 100°C to obtain a gas separation membrane A1.

[0065] (2) Removal of oxygen from oxygen-containing organic gases

[0066] exist Figure 1 The deoxygenation system shown in the figure is implemented, and the deoxygenation system includes an adsorption drying device, a heat exchanger, a membrane separation device and a distillation tower, the gas outlet of the adsorption drying device is connected to the gas inlet of the heat exchanger, the gas outlet of the heat exchanger is connected to the gas inlet of the membrane separation device, the retentate side gas outlet of the membrane separation device is connected to the gas inlet of the distillation tower, a pressure reducing valve is provided on the connecting pipeline between the adsorption drying device and the heat exchanger, a vacuum pump is provided on the pipeline of the permeate side gas outlet of the membrane separation device, wherein a gas separation membrane A1 is provided in the membrane separation device, and an online oxygen content analyzer is provided at the gas inlet of the adsorption drying device, the permeate side gas outlet of the membrane separation device and the gas inlet of the distillation tower.

[0067] The oxygen-containing organic gas used in this embodiment is the HPPO process propylene oxide process tail gas (also called propylene tail gas), and its composition is: oxygen concentration is 6% by volume, propylene concentration is 93% by volume, water vapor concentration is 1% by volume, feed pressure is 1.0 MPaG, and feed temperature is 45°C.

[0068] The olefin tail gas is transported to an adsorption drying device for drying, reduced in pressure to 0.5 MPaG by a pressure reducing valve, cooled to 20°C by a heat exchanger, and then enters a membrane separation device for deoxygenation treatment. The oxygen concentration of the gas on the permeate side of the membrane separation device is 92.1% by volume, and the oxygen concentration of the gas on the retentate side is 0.5% by volume.

[0069] The retentate side gas is transported to a distillation tower for separation treatment, whereby non-condensable gas is separated from the gas phase and propylene is separated from the liquid phase.

[0070] Example 2

[0071] (1) Preparation of gas separation membrane

[0072] After 100 g of polysulfone powder (average degree of polymerization of 55, purchased from Sinopharm Reagent Company) was dissolved in 500 g of dimethylformamide at 80°C, 4 g of white carbon black (nanoparticles, particle size of 10-25 nm) was added to the mixture, and 5 g of polyethylene glycol (weight average molecular weight of 4000, purchased from Aladdin Company) was added to the mixed system under stirring. The obtained mixed slurry was then uniformly coated on a porous alumina plate at 20°C and evaporated at 160°C to obtain a gas separation membrane A2.

[0073] (2) Removal of oxygen from oxygen-containing organic gases

[0074] exist Figure 1 The deoxygenation system shown in the figure is implemented, and the deoxygenation system includes an adsorption drying device, a heat exchanger, a membrane separation device and a distillation tower, the gas outlet of the adsorption drying device is connected to the gas inlet of the heat exchanger, the gas outlet of the heat exchanger is connected to the gas inlet of the membrane separation device, the permeate side gas outlet of the membrane separation device is connected to the gas inlet of the distillation tower, a pressure reducing valve is provided on the connecting pipeline between the adsorption drying device and the heat exchanger, a vacuum pump is provided on the pipeline of the permeate side gas outlet of the membrane separation device, wherein a gas separation membrane A2 is provided in the membrane separation device, and an online oxygen content analyzer is provided at the gas inlet of the adsorption drying device, the permeate side gas outlet of the membrane separation device and the gas inlet of the distillation tower.

[0075] The oxygen-containing organic gas used in this embodiment is the HPPO process propylene oxide process tail gas (also called propylene tail gas), and its composition is: oxygen concentration is 3 volume%, propylene concentration is 96.5 volume%, water vapor concentration is 0.5 volume%, feed pressure is 2.0 MPaG, and feed temperature is 65°C.

[0076] The olefin tail gas is transported to an adsorption drying device for drying, reduced in pressure to 0.5 MPaG by a pressure reducing valve, cooled to 10°C by a heat exchanger, and then enters a membrane separation device for deoxygenation treatment. The oxygen concentration of the gas on the permeate side of the membrane separation device is 95.0% by volume, and the oxygen concentration of the gas on the retentate side is 0.2% by volume.

[0077] The retentate side gas is transported to a distillation tower for separation treatment, whereby non-condensable gas is separated from the gas phase and propylene is separated from the liquid phase.

[0078] Example 3

[0079] (1) Preparation of gas separation membrane

[0080] 100g of polysulfone powder (average degree of polymerization of 80, purchased from Sinopharm Reagent Company) was stirred at 50°C for 2h in 1kg of 0.1mol / L nitric acid solution, then washed with deionized water and dried at 65°C to obtain a modified polysulfone resin. The modified polysulfone resin was dissolved in 400g of dimethylformamide at 130°C, 4g of S-1 molecular sieve (flaky particles, particle size of 10-40nm) was added to the mixture, and 5g of polyethylene glycol (weight average molecular weight of 3000, purchased from Aladdin Company) was added to the mixed system under stirring. The obtained mixed slurry was then uniformly coated on a porous alumina flat plate at 30°C and evaporated at 160°C to obtain a gas separation membrane A3.

[0081] (2) Removal of oxygen from oxygen-containing organic gases

[0082] exist Figure 1 The deoxygenation system shown in the figure is implemented, and the deoxygenation system includes an adsorption drying device, a heat exchanger, a membrane separation device and a distillation tower, the gas outlet of the adsorption drying device is connected to the gas inlet of the heat exchanger, the gas outlet of the heat exchanger is connected to the gas inlet of the membrane separation device, the retentate side gas outlet of the membrane separation device is connected to the gas inlet of the distillation tower, a pressure reducing valve is provided on the connecting pipeline between the adsorption drying device and the heat exchanger, a vacuum pump is provided on the pipeline of the permeate side gas outlet of the membrane separation device, wherein a gas separation membrane A3 is provided in the membrane separation device, and an online oxygen content analyzer is provided at the gas inlet of the adsorption drying device, the permeate side gas outlet of the membrane separation device and the gas inlet of the distillation tower.

[0083] The oxygen-containing organic gas used in this embodiment is the HPPO process propylene oxide process tail gas (also called propylene tail gas), and its composition is: oxygen concentration is 10 volume%, propylene concentration is 89.5 volume%, water vapor concentration is 0.5 volume%, feed pressure is 2.0 MPaG, and feed temperature is 65°C.

[0084] The olefin tail gas is transported to an adsorption drying device for drying, reduced in pressure to 1.5 MPaG by a pressure reducing valve, cooled to 5°C by a heat exchanger, and then enters a membrane separation device for deoxygenation treatment. The oxygen concentration of the gas on the permeate side of the membrane separation device is 91.3% by volume, and the oxygen concentration of the gas on the retentate side is 0.9% by volume.

[0085] The retentate side gas is transported to a distillation tower for separation treatment, whereby non-condensable gas is separated from the gas phase and propylene is separated from the liquid phase.

[0086] Example 4

[0087] (1) Preparation of gas separation membrane

[0088] 100g of polysulfone powder (average degree of polymerization of 30, purchased from Sinopharm Reagent Company) was stirred in 1kg of glycerol solution at 100°C for 2h, then washed with deionized water and dried at 100°C to obtain a modified polysulfone resin. The modified polysulfone resin was dissolved in 400g of chloroform at 130°C, 5g of white carbon black (nanoparticles, particle size of 15-20nm) was added to the mixture, and 5g of polyethylene glycol (weight average molecular weight of 4000, purchased from Aladdin Company) was added to the mixed system under stirring. The obtained mixed slurry was then uniformly coated on a porous titanium oxide plate at 30°C and evaporated at 160°C to obtain a gas separation membrane A4.

[0089] (2) Removal of oxygen from oxygen-containing organic gases

[0090] exist Figure 1 The deoxygenation system shown in the figure is implemented, and the deoxygenation system includes an adsorption drying device, a heat exchanger, a membrane separation device and a distillation tower, the gas outlet of the adsorption drying device is connected to the gas inlet of the heat exchanger, the gas outlet of the heat exchanger is connected to the gas inlet of the membrane separation device, the permeate side gas outlet of the membrane separation device is connected to the gas inlet of the distillation tower, a booster pump is provided on the connecting pipeline between the adsorption drying device and the heat exchanger, and a vacuum pump is provided on the pipeline of the permeate side gas outlet of the membrane separation device, wherein a gas separation membrane A4 is provided in the membrane separation device, and an online oxygen content analyzer is provided at the gas inlet of the adsorption drying device, the permeate side gas outlet of the membrane separation device and the gas inlet of the distillation tower.

[0091] The oxygen-containing organic gas used in this embodiment is the HPPO process propylene oxide process tail gas (also called propylene tail gas), and its composition is: oxygen concentration is 8% by volume, propylene concentration is 91.8% by volume, water vapor concentration is 0.2% by volume, feed pressure is 0.1MPaG, and feed temperature is 65°C.

[0092] The olefin tail gas is transported to an adsorption drying device for drying, pressurized to 0.5 MPaG by a booster pump, cooled to 5°C by a heat exchanger, and then enters a membrane separation device for deoxygenation treatment. The oxygen concentration of the gas on the permeate side of the membrane separation device is 92.2% by volume, and the oxygen concentration of the gas on the retentate side is 0.5% by volume.

[0093] The retentate side gas is transported to a distillation tower for separation treatment, whereby non-condensable gas is separated from the gas phase and propylene is separated from the liquid phase.

[0094] Example 5

[0095] (1) Preparation of gas separation membrane

[0096] A gas separation membrane was prepared according to the method of Example 1, except that the inorganic matrix added was 3g S-1 molecular sieve (flaky particles, particle size 40-70nm) and 1g white carbon black (nanoparticles, particle size 15-30nm), thereby preparing gas separation membrane A5.

[0097] (2) Removal of oxygen from oxygen-containing organic gases

[0098] The oxygen in the oxygen-containing organic gas is removed according to the method of Example 1, except that the separation membrane in the membrane separation device is the gas separation membrane A5.

[0099] As a result, the oxygen concentration of the gas on the permeate side of the membrane separation device was 92.4% by volume, and the oxygen concentration of the gas on the retentate side was 0.3% by volume.

[0100] Comparative Example 1

[0101] (1) Preparation of gas separation membrane

[0102] A gas separation membrane was prepared according to the method of Example 1, except that the inorganic matrix added was a micron-sized block S-1 molecular sieve (particle size was 2-4 microns), thereby obtaining a gas separation membrane D1.

[0103] (2) Removal of oxygen from oxygen-containing organic gases

[0104] The oxygen in the oxygen-containing organic gas is removed according to the method of Example 1, except that the separation membrane in the membrane separation device is the gas separation membrane D1.

[0105] As a result, the oxygen concentration of the gas on the permeate side of the membrane separation device was 74.2% by volume, and the oxygen concentration of the gas on the retentate side was 4.2% by volume.

[0106] Comparative Example 2

[0107] (1) Preparation of gas separation membrane

[0108] A gas separation membrane was prepared according to the method of Example 1, except that polyacrylic acid (weight average molecular weight of 8000, purchased from Aladdin) was used instead of polysulfone resin to prepare gas separation membrane D2.

[0109] (2) Removal of oxygen from oxygen-containing organic gases

[0110] The oxygen in the oxygen-containing organic gas is removed according to the method of Example 1, except that the separation membrane in the membrane separation device is the gas separation membrane D2.

[0111] As a result, the oxygen concentration of the gas on the permeate side of the membrane separation device was 10.8% by volume, and the oxygen concentration of the gas on the retentate side was 5.6% by volume.

[0112] Comparative Example 3

[0113] (1) Preparation of gas separation membrane

[0114] A gas separation membrane was prepared according to the method of Example 1, except that polyethylene glycol was not added during the preparation process, thereby obtaining a gas separation membrane D3.

[0115] (2) Removal of oxygen from oxygen-containing organic gases

[0116] The oxygen in the oxygen-containing organic gas is removed according to the method of Example 1, except that the separation membrane in the membrane separation device is the gas separation membrane D3.

[0117] As a result, the oxygen concentration of the gas on the permeate side of the membrane separation device was 90.1% by volume, and the oxygen concentration of the gas on the retentate side was 1.4% by volume.

[0118] Comparative Example 4

[0119] The gas separation membrane was prepared and oxygen in the oxygen-containing organic gas was removed according to the method of Example 1, except that during the deoxygenation process, the pressure and temperature of the propylene tail gas were not adjusted, and the dried propylene tail gas was directly transported to the membrane separation device for deoxygenation.

[0120] As a result, the oxygen concentration of the gas on the permeate side of the membrane separation device was 90.4% by volume, and the oxygen concentration of the gas on the retentate side was 1.1% by volume.

[0121] It can be seen from the results of the above examples and comparative examples that the use of the gas separation membrane of the present invention to deoxygenate oxygen-containing organic gas can achieve a better deoxygenation effect.

[0122] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A gas separation membrane, characterized in that: The gas separation membrane comprises a high molecular polymer and an inorganic matrix dispersed in the high molecular polymer, wherein the content of the inorganic matrix is ​​0.5-10 parts by weight relative to 100 parts by weight of the high molecular polymer, wherein the high molecular polymer is a modified or unmodified polysulfone resin, and the inorganic matrix is ​​nanoparticles with a particle size of less than 500nm.

2. The gas separation membrane according to claim 1, characterized in that The polymerization degree of the high molecular polymer is 5-100, preferably 30-80.

3. The gas separation membrane according to claim 1 or 2, characterized in that The modified polysulfone resin is a polysulfone resin modified by nitric acid and / or a polysulfone resin modified by glycerol.

4. The gas separation membrane according to any one of claims 1 to 3, characterized in that: The inorganic matrix is ​​at least one of molecular sieve, white carbon black, silica gel and alumina.

5. A method for removing oxygen from an oxygen-containing organic gas, the method comprising: The oxygen-containing organic gas is transported to a membrane separation device for deoxygenation treatment, wherein the membrane separation device is provided with a gas separation membrane according to any one of claims 1 to 4.

6. The method according to claim 5, characterized in that The oxygen-containing organic gas enters the membrane separation device after being dried, pressure-regulated and temperature-regulated.

7. The method according to claim 6, characterized in that By adjusting the pressure and temperature, the temperature of the oxygen-containing organic gas entering the membrane separation device is set to 0-50° C. and the pressure is set to 0.2-1.5 MPaG.

8. The method according to any one of claims 5 to 7, characterized in that: The oxygen-containing organic gas is at least one of the tail gas of the HPPO process propylene oxide, the tail gas of the hydrogen peroxide process epichlorohydrin process and the tail gas of the ethylene process ethylene oxide.

9. A system for removing oxygen from oxygen-containing organic gas, characterized in that: The system includes: A drying device (2), used for drying the oxygen-containing organic gas; A temperature regulating device (3) is used to regulate the temperature of the oxygen-containing organic gas after the drying process; A pressure regulating device (9), arranged on the connecting pipe between the drying device (2) and the temperature regulating device (3), for regulating the pressure of the oxygen-containing organic gas; a membrane separation device (4) for deoxygenating the oxygen-containing organic gas from the temperature regulating device (3) to obtain a permeate-side gas mainly containing oxygen and a deoxygenated retentate-side gas, wherein the membrane separation device (4) is provided with a gas separation membrane according to any one of claims 1 to 4; The non-condensable gas separation tower (8) is used to process the retentate side gas from the membrane separation device (4) and separate the non-condensable gas from the gas phase.

10. The system according to claim 9, characterized in that A first online oxygen content analyzer (1) is provided at the air inlet of the drying device (2), a second online oxygen content analyzer (6) is provided at the gas outlet on the permeate side of the membrane separation device (4), and a third online oxygen content analyzer (5) is provided at the gas outlet on the retentate side of the membrane separation device (4).

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