Molecular sieve-based adsorbent material, method for preparing the same, and use thereof

Abstract

The application relates to the technical field of adsorbing materials, and discloses a molecular sieve-based adsorbing material and a preparation method and application thereof. The method comprises the following steps: dispersing a silicon source and tetrapropylammonium bromide in water, mixing the obtained mixture with inorganic alkali and ammonium fluoride to obtain a gel, and then sequentially performing crystallization and calcination on the gel, wherein the water is used in an amount of 100-250 parts by weight relative to 100 parts by weight of the silicon source. According to the method, the wettability of the molecular sieve material is finely adjusted by adjusting the material composition, the adsorption selectivity of the material for 3-chloropropylene molecules in a nitrogen atmosphere is improved, the adsorption recovery of 3-chloropropylene materials in a rectification separation unit in an epoxidized chloropropane process by the hydrogen peroxide method is realized, a matched deoxygenation and nitrogen recovery and utilization process is designed, the nitrogen consumption of the system is further reduced, and the profit level of the device is improved.

Description

Technical Field

[0001] This invention relates to the field of adsorption materials technology, specifically to a molecular sieve-based adsorption material, its preparation method and application, and more specifically, to a molecular sieve-based adsorption material and its preparation method, a 3-chloropropene adsorption and recovery method, and a method for treating the tail gas from the hydrogen peroxide process for producing epichlorohydrin. Background Technology

[0002] The oxidation of 3-chloropropene with hydrogen peroxide to produce epichlorohydrin has gradually shown unique advantages in the field of epoxy compound preparation due to its high atom utilization rate and low wastewater and waste residue discharge. However, because hydrogen peroxide is extremely prone to decomposition and produces oxygen, certain measures have been taken in actual chemical processes to eliminate the safety risks posed by the oxygen produced by the decomposition of hydrogen peroxide.

[0003] Hydrogen peroxide readily decomposes into oxygen under the catalytic action of alkalis, metal ions, and high temperatures. The mixture of oxygen and organic gases poses a risk of combustion and explosion. This oxygen, when mixed with methanol and 3-chloropropene vapors, forms an explosive mixture, threatening the safe and stable operation of industrial plants. Nitrogen dilution can effectively eliminate this risk. However, 3-chloropropene is one of the main raw materials in the hydrogen peroxide process for epichlorohydrin production. Its boiling point is 45°C under normal pressure, and nitrogen purging results in significant losses of 3-chloropropene during subsequent distillation and separation processes. Therefore, it is necessary to develop a 3-chloropropene recovery method suitable for the hydrogen peroxide process for epichlorohydrin production.

[0004] Current technologies for treating chlorinated hydrocarbons primarily focus on the catalytic removal of low concentrations of halogenated hydrocarbons. However, in the recycling field, due to the small molecular weight of 3-chloropropene and its weak van der Waals forces with adsorbents, existing adsorbent materials often fail to achieve excellent adsorption performance. Furthermore, the preparation methods for core adsorbent materials are often complex and costly, limiting their practical industrial applications.

[0005] Therefore, we continue to develop a molecular sieve-based adsorbent material that, while having a simple preparation method, can improve the adsorption selectivity of the material for 3-chloropropene molecules in a diluted atmosphere and reduce costs. Summary of the Invention

[0006] The purpose of this invention is to overcome the problems of existing adsorption materials often failing to achieve excellent adsorption performance in the adsorption and recovery process of 3-chloropropene, as well as the complexity and high cost of adsorption material preparation methods. This invention provides a molecular sieve-based adsorption material, its preparation method, and its application. Based on the size matching principle and hydrophilicity / hydrophobicity of molecular sieves, this invention designs a unique multi-level porous molecular sieve material as an adsorbent. By adjusting the material composition and finely modulating the wettability of the molecular sieve material, the adsorption selectivity of the material for 3-chloropropene molecules in a diluted gas atmosphere is improved. This achieves the adsorption and recovery of 3-chloropropene material in the distillation separation unit of the hydrogen peroxide-based epichlorohydrin production process. Simultaneously, a matching deoxygenation and dilution gas recovery and utilization process is designed to further reduce nitrogen consumption and improve the profitability of the equipment.

[0007] To achieve the above objectives, the first aspect of the present invention provides a method for preparing a molecular sieve-based adsorbent material, the method comprising: dispersing a silicon source and tetrapropylammonium bromide in water, mixing the resulting mixture with an inorganic base and ammonium fluoride to obtain a gel, and then sequentially crystallizing and calcining the gel, wherein the amount of water used is 100-250 parts by weight relative to 100 parts by weight of the silicon source.

[0008] Preferably, relative to 100 parts by weight of the silicon source, the amount of tetrapropylammonium bromide is 10-120 parts by weight, the amount of the inorganic base is 5-40 parts by weight, and the amount of ammonium fluoride is 5-15 parts by weight.

[0009] Preferably, the inorganic base is caustic soda and / or sodium carbonate.

[0010] Preferably, the silicon source is silica gel and / or silica.

[0011] Preferably, the crystallization conditions include a temperature of 150-200°C and a time of 48-150 hours.

[0012] Preferably, the calcination conditions include: a temperature of 450-650℃ and a time of 4-7 hours.

[0013] A second aspect of the present invention provides a molecular sieve-based adsorbent material prepared by the method described above.

[0014] A third aspect of the present invention provides a method for the adsorption and recovery of 3-chloropropene, the method comprising: contacting tail gas containing 3-chloropropene with an adsorbent material, wherein the adsorbent material is the aforementioned molecular sieve-based adsorbent material.

[0015] Preferably, the exhaust gas containing 3-chloropropene contains 0.1-8 vol.% 3-chloropropene and 0.5-3 vol.% oxygen.

[0016] Preferably, the tail gas containing 3-chloropropene first enters the adsorption separation unit for treatment, and then enters the deoxygenation unit for treatment, wherein the adsorbent material is packed in the adsorption separation unit as an adsorption bed.

[0017] The fourth aspect of the present invention provides a method for treating the tail gas from the hydrogen peroxide process for producing epichlorohydrin. The method includes: conveying the product of the hydrogen peroxide process for producing epichlorohydrin and dilution gas to a gas-liquid separation device for separation treatment; conveying the tail gas containing 3-chloropropene separated by the gas-liquid separation device to an adsorption separation unit for adsorption treatment; and then conveying the tail gas after adsorption treatment to a deoxygenation unit for deoxygenation treatment. The adsorption bed in the adsorption separation unit is the aforementioned molecular sieve-based adsorption material.

[0018] Preferably, the method further includes: pressurizing the mixed gas containing dilution gas obtained after deoxygenation treatment and returning it to the gas-liquid separation device for recycling.

[0019] The method for preparing molecular sieve-based adsorbent materials using the above technical solution is simple to operate. By adding inorganic alkali and ammonium fluoride during the preparation process, the defect rate of crystal growth is reduced, effectively improving the crystallinity of the material and the adsorption selectivity for 3-chloropropene. Furthermore, in the treatment of tail gas from the hydrogen peroxide process for epichlorohydrin production, the prepared molecular sieve-based adsorbent material can significantly reduce the loss of 3-chloropropene and the consumption of dilution gas, thereby reducing costs and improving profitability. Simultaneously, the molecular sieve-based adsorbent material described in this invention also shows promising applications in many other chemical processes involving hydrocarbon recovery and utilization, such as oil and gas recovery from storage tanks and VOCs recovery. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the molecular sieve-based adsorption material adsorbing organic matter according to the present invention;

[0021] Figure 2 This is a schematic diagram of the process flow for the tail gas treatment system in the hydrogen peroxide process for producing epichlorohydrin.

[0022] Figure 3 This is the XRD pattern of the molecular sieve-based adsorption material described in this invention.

[0023] Explanation of reference numerals in the attached figures

[0024] 1. Gas-liquid separation equipment; 2. Adsorption separation unit; 3. Deoxygenation unit; 4. Pressure control unit; 5. Desulfurization device. Detailed Implementation

[0025] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0026] The endpoints and any values ​​of the ranges disclosed herein 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 the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0027] The method for preparing the molecular sieve-based adsorbent material of the present invention includes: dispersing a silicon source and tetrapropylammonium bromide in water; mixing the resulting mixture with an inorganic base and ammonium fluoride to obtain a gel; and then sequentially crystallizing and calcining the gel. The amount of water used is 100-250 parts by weight relative to 100 parts by weight of the silicon source. According to the method of the present invention, by mixing a silicon source, a structure-directing agent, a mineralizing agent, and a small amount of water to obtain a gel, then removing sodium ions using ammonium exchange, and finally calcining, a molecular sieve-based adsorbent material is obtained. This simplifies the preparation method of the molecular sieve-based adsorbent material, reduces the defect rate of crystal material growth, and effectively improves the crystallinity of the material and the adsorption selectivity for 3-chloropropene.

[0028] In the method described in this invention, in order to improve the adsorption performance of the molecular sieve-based adsorbent material, the amount of water used is preferably 100-200 parts by weight relative to 100 parts by weight of the silicon source, specifically for example, 100 parts by weight, 110 parts by weight, 120 parts by weight, 130 parts by weight, 140 parts by weight, 150 parts by weight, 160 parts by weight, 170 parts by weight, 180 parts by weight, 190 parts by weight, or 200 parts by weight.

[0029] In the method described in this invention, the method may further include: dispersing a silicon source and tetrapropylammonium bromide in water under a first stirring, and then mixing the resulting mixture with an inorganic base and ammonium fluoride under a second stirring to obtain a gel. The conditions for the first stirring include: a stirring rate of 5-60 rpm, preferably 10-25 rpm; a temperature of 0-50°C, preferably 15-35°C; and a time of 5-60 min, preferably 10-30 min. The conditions for the second stirring include: a stirring rate of 10-50 rpm, preferably 15-20 rpm; a temperature of 15-35°C, preferably 23-27°C; and a time of 10-100 min, preferably 20-40 min.

[0030] In the method described in this invention, the amount of tetrapropylammonium bromide used relative to 100 parts by weight of the silicon source can be 10-120 parts by weight, preferably 15-100 parts by weight; the amount of the inorganic base can be 5-40 parts by weight, preferably 5-35 parts by weight; and the amount of ammonium fluoride can be 5-15 parts by weight, preferably 5-10 parts by weight.

[0031] In the method described in this invention, in order to reduce the growth defect rate of crystal materials and improve the crystallinity of materials, the inorganic base is preferably sodium hydroxide and / or sodium carbonate.

[0032] In the method described in this invention, in order to ensure the adsorption performance of the molecular sieve-based adsorbent material, the silicon source is preferably silica gel and / or silica.

[0033] In the method described in this invention, the crystallization conditions include: a temperature of 150-200℃, preferably 150-180℃, specifically 150℃, 155℃, 160℃, 165℃, 170℃, 175℃, or 180℃; and a time of 48-150 hours, preferably 48-120 hours. The crystallization process may also include a third stirring. The stirring rate of the third stirring is 5-60 rpm, preferably 10-20 rpm. The crystallization process can be carried out in a stainless steel crystallization reactor lined with polytetrafluoroethylene.

[0034] In the method described in this invention, the method may further include: washing and drying the crystallized material. The washing may be performed by rinsing with water. The drying conditions include: a temperature of 70-90°C, preferably 75-85°C; and a time of 5-10 hours, preferably 7-9 hours.

[0035] In the method described in this invention, the calcination conditions include: a temperature of 450-650℃, preferably 500-600℃, specifically for example, 500℃, 510℃, 520℃, 530℃, 540℃, 550℃, 560℃, 570℃, 580℃, 590℃, or 600℃; and a time of 4-7 hours, preferably 4-6 hours.

[0036] In some embodiments, the preparation method of the molecular sieve-based adsorbent material of the present invention includes: dispersing silica gel and tetrapropylammonium bromide in water; mixing the resulting mixture with caustic soda and ammonium fluoride to obtain a gel; and then sequentially crystallizing and calcining the gel, wherein, relative to 100 parts by weight of the silicon source, the amount of water is 100-250 parts by weight, the amount of tetrapropylammonium bromide is 10-120 parts by weight, the amount of the inorganic base is 5-40 parts by weight, and the amount of ammonium fluoride is 5-15 parts by weight. Preferably, relative to 100 parts by weight of the silicon source, the amount of water is 100-200 parts by weight, the amount of tetrapropylammonium bromide is 15-100 parts by weight, the amount of the inorganic base is 5-35 parts by weight, and the amount of ammonium fluoride is 2-10 parts by weight.

[0037] In other embodiments, the preparation method of the molecular sieve-based adsorbent material of the present invention includes: dispersing silica and tetrapropylammonium bromide in water; mixing the resulting mixture with sodium carbonate and ammonium fluoride to obtain a gel; and then sequentially crystallizing and calcining the gel, wherein, relative to 100 parts by weight of the silicon source, the amount of water is 100-250 parts by weight, the amount of tetrapropylammonium bromide is 10-120 parts by weight, the amount of the inorganic base is 5-40 parts by weight, and the amount of ammonium fluoride is 5-15 parts by weight. Preferably, relative to 100 parts by weight of the silicon source, the amount of water is 100-200 parts by weight, the amount of tetrapropylammonium bromide is 15-100 parts by weight, the amount of the inorganic base is 5-35 parts by weight, and the amount of ammonium fluoride is 2-10 parts by weight.

[0038] This invention also provides a molecular sieve-based adsorbent material prepared by the above-described method. The molecular sieve-based adsorbent material according to this invention is an inorganic material with unique pores and topology, wherein 3-chloropropene can diffuse into the pores of a 10-membered ring molecular sieve (pore diameter 4.5-5.5 nm), achieving physical adsorption through van der Waals forces between 3-chloropropene molecules and the molecular sieve material. The material exhibits low selectivity for dilution gases and oxygen, thereby enabling the recovery and utilization of the 3-chloropropene species.

[0039] This invention also provides a method for the adsorption and recovery of 3-chloropropene, comprising: contacting tail gas containing 3-chloropropene with an adsorbent material, wherein the adsorbent material is the aforementioned molecular sieve-based adsorbent material. The 3-chloropropene adsorption and recovery method according to this invention can improve the utilization rate of 3-chloropropene materials.

[0040] In the 3-chloropropene adsorption and recovery method of the present invention, the tail gas containing 3-chloropropene may contain 0.1-8 vol.% 3-chloropropene and 0.5-3 vol.% oxygen, with the remainder being dilution gas; preferably, it contains 3-7 vol.% 3-chloropropene and 2-3 vol.% oxygen, with the remainder being dilution gas. The dilution gas may contain at least one of nitrogen, argon, and alkanes. The alkanes may be at least one of methane, ethane, and propane.

[0041] In the 3-chloropropene adsorption and recovery method of this invention, the tail gas containing 3-chloropropene first enters the adsorption separation unit for treatment, and then enters the deoxygenation unit for treatment. The adsorbent material is packed in the adsorption separation unit as an adsorption bed. Figure 1 As shown, the adsorbent material achieves throttling within the adsorption bed through selective action on 3-chloropropene species, and the outlet of the adsorption bed is a mixture of dilution gas and oxygen.

[0042] This invention also provides a method for treating the tail gas from the hydrogen peroxide process for producing epichlorohydrin. The method includes: conveying the product from the hydrogen peroxide process for epichlorohydrin production and dilution gas to a gas-liquid separation device 1 for separation; conveying the tail gas containing 3-chloropropene separated by the gas-liquid separation device 1 to an adsorption separation unit 2 for adsorption treatment; and then conveying the adsorbed tail gas to a deoxygenation unit 3 for deoxygenation treatment. The adsorption bed in the adsorption separation unit 2 is the molecular sieve-based adsorption material described in this invention. The method for treating the tail gas from the hydrogen peroxide process for producing epichlorohydrin according to this invention has intrinsic safety characteristics and can improve the utilization rate of 3-chloropropene materials.

[0043] In the method for treating the tail gas from the hydrogen peroxide process for producing epichlorohydrin according to the present invention, after the adsorption bed has completed adsorption, 3-chloropropene can be recovered by condensation, or it can be recovered for 2-10 hours at a temperature of 50-100℃ and a vacuum of 1-50 kPaA. The condensation temperature can be -10-15℃, preferably 0-5℃. In this document, the vacuum degree is atmospheric pressure minus absolute pressure.

[0044] In the method for treating the tail gas from the hydrogen peroxide process for producing epichlorohydrin according to the present invention, the dilution gas may contain at least one of nitrogen, argon, and alkanes. The alkanes may be at least one of methane, ethane, and propane.

[0045] In some embodiments, when the diluent gas is nitrogen, the 3-chloropropene-containing tail gas contains 0.1-8 vol.% 3-chloropropene, 0.5-3 vol.% oxygen, and 89-95.4 vol.% nitrogen. In a more preferred embodiment, the 3-chloropropene-containing tail gas contains 3-7 vol.% 3-chloropropene, 2-3 vol.% oxygen, and 90-95 vol.% nitrogen.

[0046] In other embodiments, when the diluent gas is argon, the tail gas containing 3-chloropropene contains 0.1-8 vol.% 3-chloropropene, 0.5-3 vol.% oxygen, and 89-95.4 vol.% argon. In a more preferred embodiment, the tail gas containing 3-chloropropene contains 3-7 vol.% 3-chloropropene, 2-3 vol.% oxygen, and 90-95 vol.% argon.

[0047] In other embodiments, when the diluent gas is methane, the tail gas containing 3-chloropropene contains 0.1-8 vol.% 3-chloropropene, 0.5-3 vol.% oxygen, and 89-95.4 vol.% methane. In a more preferred embodiment, the tail gas containing 3-chloropropene contains 3-7 vol.% 3-chloropropene, 2-3 vol.% oxygen, and 90-95 vol.% methane.

[0048] In other embodiments, when the diluent gas is ethane, the tail gas containing 3-chloropropene contains 0.1-8 vol.% 3-chloropropene, 0.5-3 vol.% oxygen, and 89-95.4 vol.% ethane. In a more preferred embodiment, the tail gas containing 3-chloropropene contains 3-7 vol.% 3-chloropropene, 2-3 vol.% oxygen, and 90-95 vol.% ethane.

[0049] In the method for treating the tail gas from the hydrogen peroxide process for producing epichlorohydrin according to the present invention, in order to reduce nitrogen consumption, the method preferably further includes: pressurizing the mixed gas containing diluent gas obtained after deoxygenation treatment and then returning it to the gas-liquid separator 1 for recycling. The pressurization can be performed by a pressure control unit 4. In the mixed gas containing diluent gas obtained after deoxygenation treatment, the content of the diluent gas is 98-100 vol.%.

[0050] In the method for treating the tail gas from the hydrogen peroxide process for producing epichlorohydrin according to the present invention, the method further includes mixing the mixed gas containing dilution gas obtained after deoxygenation treatment with the gas from the desulfurization unit 5, pressurizing it to 0.5-1.0 MPa, and then returning it to the gas-liquid separation unit 1 for recycling. The gas from the desulfurization unit 5 may contain at least one of methane, ethane, nitrogen, and an inert gas, wherein the inert gas may be argon. In a preferred embodiment, the gas from the desulfurization unit 5 contains at least one of methane, nitrogen, and argon.

[0051] In the method for treating the tail gas from the hydrogen peroxide process for producing epichlorohydrin according to the present invention, the method further includes: monitoring the oxygen content at the inlet of the deoxygenation unit 3, the oxygen content on the permeation side of the deoxygenation unit 3, and the oxygen content on the residual side of the deoxygenation unit 3 using an oxygen content analyzer. When the oxygen content at the inlet of the deoxygenation unit 3 is higher than 5 vol.%, the amount of dilution gas introduced into the gas-liquid separator 1 is increased. The purpose of monitoring the oxygen content on the permeation side of the deoxygenation unit 3 is to ensure that the oxygen content in the tail gas is maintained within the safe range of 0-5 vol.%, preventing potential safety risks. The purpose of monitoring the oxygen content on the residual side of the deoxygenation unit 3 is to ensure that the oxygen content of the mixed gas containing dilution gas obtained after the deoxygenation treatment is lower than 2 vol.%, so that it can be returned to the gas-liquid separator 1 for recycling.

[0052] The method for treating the tail gas from the hydrogen peroxide process for producing epichlorohydrin, as described in this invention, is carried out in a tail gas treatment system for the hydrogen peroxide process for producing epichlorohydrin, such as... Figure 2 As shown, the system may include: a gas-liquid separation device 1, an adsorption separation unit 2, and a deoxygenation unit 3. The gas-liquid separation device 1 is used to separate the product of epichlorohydrin produced by the hydrogen peroxide method and separate the tail gas containing 3-chloropropene. The adsorption separation unit 2 is used to adsorb the separated tail gas containing 3-chloropropene. The deoxygenation unit 3 is used to deoxygenate the tail gas after adsorption treatment.

[0053] In the system described in this invention, the adsorption separation unit 2 may include two adsorption beds. In a specific embodiment, when one adsorption bed is in operation, the other adsorption bed is shut down.

[0054] In the system described in this invention, the system may further include: a pressure control unit 4, which is used to pressurize the mixed gas containing dilution gas obtained after deoxygenation treatment to 0.5-1.0 MPa and return it to the gas-liquid separation device 1 for recycling.

[0055] In the system described in this invention, the system may further include: a desulfurization device 5, which is used to provide gas, and then the gas provided by the desulfurization device 5 is mixed with a mixed gas containing dilution gas obtained after deoxygenation treatment.

[0056] In the system described in this invention, the system may further include: an oxygen content analyzer, which is used to monitor the oxygen content at the inlet of the deoxygenation unit 3, the oxygen content on the permeation side of the deoxygenation unit 3, and the oxygen content on the permeation side of the deoxygenation unit 3, respectively. When the oxygen content at the inlet of the deoxygenation unit 3 is higher than 5 vol.%, the amount of dilution gas introduced into the gas-liquid separation device 1 is increased to control the oxygen content at the inlet of the deoxygenation unit 3 to be 0-5 vol.%.

[0057] In the system described in this invention, the system may further include: a gas mass flow meter and a valve, wherein the gas mass flow meter is used to monitor the gas mass flow rate, and the valve controls the gas mass flow rate.

[0058] In some implementations, such as Figure 2 As shown, the tail gas treatment system for the hydrogen peroxide method of epichlorohydrin production includes: a gas-liquid separation device 1, an adsorption separation unit 2, a deoxygenation unit 3, a pressure control unit 4, a desulfurization device 5, and three oxygen content analyzers. The gas-liquid separation device 1 is used to separate the product of the hydrogen peroxide method of epichlorohydrin production and separate the tail gas containing 3-chloropropene. The adsorption separation unit 2 is used to adsorb the separated tail gas containing 3-chloropropene. The deoxygenation unit 3 is used to deoxygenate the tail gas after adsorption treatment. The pressure control unit 4 is used to pressurize the mixed gas containing diluent gas obtained after deoxygenation treatment to 0.5-1.0 MPa and return it to the gas-liquid separation device 1 for recycling. The desulfurization device 5 is used to provide mixed gas, and then the mixed gas provided by the desulfurization device 5 is mixed with the mixed gas containing diluent gas obtained after deoxygenation treatment. The oxygen content analyzer is used to monitor the oxygen content at the inlet of the deoxygenation unit 3, the oxygen content on the permeation side of the deoxygenation unit 3, and the oxygen content on the permeation side of the deoxygenation unit 3, respectively. When the oxygen content at the inlet of the deoxygenation unit 3 is higher than 5 vol.%, the amount of dilution gas introduced into the gas-liquid separation device 1 is increased to control the oxygen content at the inlet of the deoxygenation unit 3 to be 0-5 vol.%.

[0059] In some embodiments, the tail gas treatment method for epichlorohydrin production using the hydrogen peroxide method of the present invention is carried out in a tail gas treatment system for epichlorohydrin production using the hydrogen peroxide method. The method includes: conveying the product of epichlorohydrin production using the hydrogen peroxide method and dilution gas to a gas-liquid separation device 1 for separation; conveying the tail gas containing 3-chloropropene separated by the gas-liquid separation device 1 to an adsorption separation unit 2 for adsorption; then conveying the adsorbed tail gas to a deoxygenation unit 3 for deoxygenation; and pressurizing the mixed gas containing dilution gas obtained after deoxygenation to 0.5-1.0 MPa and returning it to the gas-liquid separation device 1 for recycling. The adsorption bed in the adsorption separation unit 2 is the molecular sieve-based adsorption material of the present invention; and the content of dilution gas in the mixed gas containing dilution gas obtained after deoxygenation is 98-100 vol.%.

[0060] In other embodiments, the tail gas treatment method for epichlorohydrin production by hydrogen peroxide method according to the present invention is carried out in a tail gas treatment system for epichlorohydrin production by hydrogen peroxide method. The method includes: conveying the product of epichlorohydrin production by hydrogen peroxide method and dilution gas to a gas-liquid separation device 1 for separation treatment; conveying the tail gas containing 3-chloropropene separated by the gas-liquid separation device 1 to an adsorption separation unit 2 for adsorption treatment; then conveying the tail gas after adsorption treatment to a deoxygenation unit 3 for deoxygenation treatment; mixing the mixed gas containing dilution gas obtained after deoxygenation treatment with the gas from the desulfurization device 5 and then passing it into a pressure control unit 4 to pressurize it to 0.5-1.0 MPa and returning it to the gas-liquid separation device 1 for recycling. The adsorption bed in the adsorption separation unit 2 is the molecular sieve-based adsorption material according to the present invention. In the mixed gas containing dilution gas obtained after deoxygenation treatment, the content of dilution gas is 98-100 vol.%, and the gas from the desulfurization device 5 contains at least one of nitrogen, argon and alkanes.

[0061] The following examples further illustrate the molecular sieve-based adsorbent materials, their preparation methods, and applications according to the present invention. These examples are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following examples.

[0062] Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods in the art. Unless otherwise specified, the experimental materials used in the following embodiments are commercially available.

[0063] The process of treating the tail gas from the hydrogen peroxide method for producing epichlorohydrin in the following examples and comparative examples is implemented in the tail gas treatment system for the hydrogen peroxide method for producing epichlorohydrin described in this invention, such as... Figure 2As shown, the system includes: a gas-liquid separation device 1, an adsorption separation unit 2, a deoxygenation unit 3, a pressure control unit 4, a desulfurization device 5, and three oxygen content analyzers. The gas-liquid separation device 1 is used to separate the product of epichlorohydrin produced by the hydrogen peroxide method and separate the tail gas containing 3-chloropropene. The adsorption separation unit 2 is used to adsorb the separated tail gas containing 3-chloropropene. The adsorption separation unit 2 includes two adsorption beds. When one adsorption bed is working, the other adsorption bed is turned off. The deoxygenation unit 3 is used to deoxygenate the tail gas after adsorption treatment. The pressure control unit 4 is used to pressurize the mixed gas containing dilution gas obtained after deoxygenation treatment to 0.5-1.0 MPa and return it to the gas-liquid separation device 1 for recycling. The desulfurization device 5 is used to provide gas, and then the gas provided by the desulfurization device 5 is mixed with the mixed gas containing dilution gas obtained after deoxygenation treatment. The oxygen content analyzer is used to monitor the oxygen content at the inlet of the deoxygenation unit 3, the oxygen content on the permeation side of the deoxygenation unit 3, and the oxygen content on the permeation side of the deoxygenation unit 3. Specifically, when the oxygen content at the inlet of the deoxygenation unit 3 is higher than 5 vol.%, the amount of dilution gas introduced into the gas-liquid separator 1 is increased to control the oxygen content at the inlet of the deoxygenation unit 3 to be 0-5 vol.%. Monitoring the oxygen content on the permeation side of the deoxygenation unit 3 ensures that the oxygen content in the exhaust gas remains within a safe range of 0-10 vol.% (if nitrogen is used as the dilution gas, the oxygen safety range can be disregarded). Monitoring the oxygen content on the permeation side of the deoxygenation unit 3 ensures that the oxygen content of the mixed gas containing dilution gas obtained after the deoxygenation treatment is lower than 2 vol.%, thus allowing it to be recycled back into the gas-liquid separator 1. The gas-liquid separator 1 includes a gas-liquid separation tank and its pipelines. The deoxygenation unit 3 includes an oxygen-permeable membrane and its components. The pressure control unit 4 includes a booster pump and a pressure reducing valve, wherein the booster pump is purchased from Suzhou Jinchao Technology Co., Ltd., and the pressure reducing valve is purchased from Beijing Sixintong Technology Co., Ltd. The desulfurization device 5 includes a zinc oxide desulfurizing agent and a desulfurization tank, wherein the zinc oxide desulfurizing agent is purchased from Sinopec Catalyst Co., Ltd.

[0064] Example 1

[0065] Preparation of molecular sieve-based adsorbent materials:

[0066] 100g of silica gel and 56g of tetrapropylammonium bromide were stirred and mixed at 10 rpm and 25°C for 20 min to disperse them in 100mL of water. 15g of caustic soda and 5g of ammonium fluoride were added, and the mixture was stirred and mixed at 10 rpm and 25°C for 30 min to obtain a gel. The gel was transferred to a stainless steel crystallization vessel with a polytetrafluoroethylene liner and crystallized at 5 rpm and 180°C for 48 h. The crystallized material was rinsed with water and dried at 80°C for 8 h, followed by calcination at 550°C for 5 h. The prepared molecular sieve-based adsorbent material was characterized by XRD. Figure 3 As shown.

[0067] Treatment of tail gas from the hydrogen peroxide method for epichlorohydrin production: The prepared molecular sieve-based adsorbent material is packed into the adsorption separation unit 2 as an adsorption bed. The product from the hydrogen peroxide method for epichlorohydrin production and the dilution gas are transported to the gas-liquid separation device 1 for separation. The tail gas containing 3-chloropropene separated by the gas-liquid separation device 1 is transported to the adsorption separation unit 2 at a rate of 50 kg / h for adsorption treatment. Then, the adsorbed tail gas is transported to the deoxygenation unit 3 for deoxygenation treatment. The nitrogen-containing mixed gas obtained after deoxygenation treatment is mixed with the gas from the desulfurization device 5 and then pressurized to 0.8 MPa by the pressure control unit 4 before being returned to the gas-liquid separation unit 1 for recycling. After the adsorption bed has completed adsorption, 3-chloropropene is recovered for 5 hours at a temperature of 50°C and a vacuum of 20 kPa. The tail gas containing 3-chloropropene contains 3 vol.% 3-chloropropene, 2 vol.% oxygen, and 95 vol.% nitrogen. The adsorption bed in the adsorption separation unit 2 is 500 kg of the molecular sieve-based adsorption material prepared in Example 1. In the tail gas after adsorption treatment, the nitrogen content is 97.8 vol.%, the 3-chloropropene content is 0.1 vol.%, and the oxygen content is 2.1 vol.%. In the nitrogen-containing mixed gas obtained after deoxygenation treatment, the nitrogen content is 99.5 vol.%, the 3-chloropropene content is 0.1 vol.%, and the oxygen content is 0.4 vol.%. The gas from the desulfurization unit 5 and the dilution gas have the same composition, specifically, each is nitrogen with a purity of 99.99 wt%, used to replenish the loss of the dilution gas during the circulation process.

[0068] Example 2

[0069] Preparation of molecular sieve-based adsorbent materials:

[0070] 100g of silica gel and 56g of tetrapropylammonium bromide were stirred at 5 rpm and 20°C for 50 min to disperse them in 100mL of water. 15g of caustic soda and 5g of ammonium fluoride were added, and the mixture was stirred at 20 rpm and 20°C for 10 min to obtain a gel. The gel was transferred to a stainless steel crystallization vessel lined with polytetrafluoroethylene (PTFE) and crystallized at 180°C for 48 h. The crystallized material was rinsed with water and dried at 80°C for 6 h, followed by calcination at 550°C for 5 h.

[0071] Treatment of tail gas from the hydrogen peroxide method for producing epichlorohydrin: The prepared molecular sieve-based adsorbent material is packed into the adsorption separation unit 2 as an adsorption bed. The product from the hydrogen peroxide method for producing epichlorohydrin and the dilution gas are transported to the gas-liquid separation device 1 for separation. The tail gas containing 3-chloropropene separated by the gas-liquid separation device 1 is transported to the adsorption separation unit 2 at a rate of 100 kg / h for adsorption treatment. Then, the adsorbed tail gas is transported to the deoxygenation unit 3 for deoxygenation treatment. The argon-containing tail gas obtained after deoxygenation treatment is then... The mixed gas from the desulfurization unit 5 is pressurized to 0.8 MPa by the pressure control unit 4 and then returned to the gas-liquid separation unit 1 for recycling. After the adsorption bed completes adsorption, 3-chloropropene is recovered by condensation for 7 hours at a temperature of 15°C and a vacuum of 35 kPaA. The tail gas containing 3-chloropropene contains 3 vol.% 3-chloropropene, 2 vol.% oxygen, and 95 vol.% argon. The adsorption bed in the adsorption separation unit 2 has a capacity of 500 kg.

[0072] The molecular sieve-based adsorbent material prepared in Example 2; in the tail gas after adsorption treatment, the content of argon is 97.7 vol.%, the content of 3-chloropropene is 0.3 vol.%, and the content of oxygen is 2 vol.%; in the argon-containing mixed gas obtained after deoxygenation treatment, the content of argon is 99.4 vol.%, the content of 3-chloropropene is 0.3 vol.%, and the content of oxygen is 0.3 vol.%; the gas from the desulfurization unit 5 and the dilution gas have the same composition, specifically, each is argon with a purity of 99.99 wt%, used to replenish the loss of dilution gas during the circulation process.

[0073] Example 3

[0074] Preparation of molecular sieve-based adsorbent materials:

[0075] 100g of silica gel and 100g of tetrapropylammonium bromide were stirred at 15 rpm and 25°C for 50 min to disperse the mixture in 200mL of water. 35g of caustic soda and 10g of ammonium fluoride were added, and the mixture was stirred at 20 rpm and 25°C for 60 min to obtain a gel. The gel was transferred to a stainless steel crystallization vessel lined with polytetrafluoroethylene (PTFE) and crystallized at 160°C for 120 h. The crystallized material was rinsed with water and dried at 80°C for 5 h, followed by calcination at 600°C for 5 h.

[0076] Treatment of tail gas from the hydrogen peroxide method for producing epichlorohydrin: The prepared molecular sieve-based adsorbent material is packed into the adsorption separation unit 2 as an adsorption bed. The product from the hydrogen peroxide method for producing epichlorohydrin and the dilution gas are transported to the gas-liquid separation device 1 for separation. The tail gas containing 3-chloropropene separated by the gas-liquid separation device 1 is transported to the adsorption separation unit 2 at a rate of 50 kg / h for adsorption treatment. Then, the adsorbed tail gas is transported to the deoxygenation unit 3 for deoxygenation treatment. The methane-containing tail gas obtained after deoxygenation treatment is then... The mixed gas and the gas from the desulfurization unit 5 are mixed and then pressurized to 0.5 MPa by the pressure control unit 4 before being returned to the gas-liquid separation unit 1 for recycling. After the adsorption bed completes adsorption, 3-chloropropene is recovered for 10 hours at a temperature of 50°C and a vacuum of 50 kPaA. The tail gas containing 3-chloropropene may contain 7 vol.% 3-chloropropene, 2 vol.% oxygen, and 91 vol.% methane. The adsorption bed in the adsorption separation unit 2 is 500 kg.

[0077] The molecular sieve-based adsorbent material prepared in Example 3; in the tail gas after adsorption treatment, the content of methane is 97 vol.%, the content of 3-chloropropene is 1.0 vol.%, and the content of oxygen is 2 vol.%; in the methane-containing mixed gas obtained after deoxygenation treatment, the content of methane is 98.5 vol.%, the content of 3-chloropropene is 0.1 vol.%, and the content of oxygen is 0.5 vol.%; the gas from the desulfurization unit 5 and the dilution gas have the same composition, specifically, methane, which is used to replenish the loss of dilution gas during the circulation process.

[0078] Example 4

[0079] Preparation of molecular sieve-based adsorbent materials:

[0080] 100g of silica gel and 100g of tetrapropylammonium bromide were stirred and mixed at 15 rpm and 35°C for 60 min to disperse them in 200mL of water. 35g of caustic soda and 10g of ammonium fluoride were added, and the mixture was stirred and mixed at 16 rpm and 25°C for 60 min to obtain a gel. The gel was transferred to a stainless steel crystallization vessel with a polytetrafluoroethylene liner and crystallized at 5 rpm and 160°C for 120 h. The crystallized material was rinsed with water and dried at 80°C for 10 h, followed by calcination at 600°C for 5 h.

[0081] Treatment of tail gas from the hydrogen peroxide method for producing epichlorohydrin: The prepared molecular sieve-based adsorbent material is loaded into the adsorption separation unit 2 as an adsorption bed. The product from the hydrogen peroxide method for producing epichlorohydrin and the dilution gas are transported to the gas-liquid separation device 1 for separation. The tail gas containing 3-chloropropene separated by the gas-liquid separation device 1 is transported to the adsorption separation unit 2 at a rate of 150 kg / h for adsorption treatment. Then, the adsorbed tail gas is transported to the deoxygenation unit 3 for deoxygenation treatment. The ethane-containing mixed gas obtained after deoxygenation treatment is mixed with the gas from the desulfurization device 5 and then pressurized to 1.0 MPa by the pressure control unit 4 before being returned to the gas-liquid separation device 1 for recycling. After the adsorption bed has completed adsorption, 3-chloropropene is recovered by condensation at a temperature of -10℃ for 10 hours. 3-chloropropene, wherein the tail gas containing 3-chloropropene contains 3 vol.% 3-chloropropene, 2 vol.% oxygen and 95 vol.% ethane; the adsorption bed in the adsorption separation unit 2 is 500 kg of the molecular sieve-based adsorption material prepared in Example 4; in the tail gas after adsorption treatment, the content of ethane is 97.9 vol.%, the content of 3-chloropropene is 0.1 vol.%, and the content of oxygen is 2 vol.%; in the ethane-containing mixed gas obtained after deoxygenation treatment, the content of ethane is 99.7 vol.%, the content of 3-chloropropene is 0.1 vol.%, and the content of oxygen is 0.2 vol.%; the gas from the desulfurization unit 5 and the dilution gas have the same composition, specifically ethane, and are used to replenish the loss of dilution gas during the circulation process.

[0082] Example 5

[0083] Preparation of molecular sieve-based adsorbent materials:

[0084] 100g of silica and 15g of tetrapropylammonium bromide were stirred at 5 rpm and 35°C for 60 min to disperse them in 200mL of water. 5g of sodium carbonate and 10g of ammonium fluoride were added, and the mixture was stirred at 20 rpm and 25°C for 60 min to obtain a gel. The gel was transferred to a stainless steel crystallization vessel lined with polytetrafluoroethylene (PTFE) and crystallized at 10 rpm and 150°C for 96 h. The crystallized material was rinsed with water and dried at 80°C for 5 h, followed by calcination at 500°C for 5 h.

[0085] Treatment of tail gas from the hydrogen peroxide method for epichlorohydrin production: The prepared molecular sieve-based adsorbent material is packed into the adsorption separation unit 2 as an adsorption bed. The product from the hydrogen peroxide method for epichlorohydrin production and the dilution gas are transported to the gas-liquid separation device 1 for separation. The tail gas containing 3-chloropropene separated by the gas-liquid separation device 1 is transported to the adsorption separation unit 2 at a rate of 100 kg / h for adsorption treatment. Then, the adsorbed tail gas is transported to the deoxygenation unit 3 for deoxygenation treatment. The nitrogen-containing mixed gas obtained after deoxygenation treatment is mixed with the gas from the desulfurization device 5 and then pressurized to 0.5 MPa by the pressure control unit 4 before being returned to the gas-liquid separation device 1 for recycling. After the adsorption bed has completed adsorption, 10 kJ of 3-chloropropene is recovered under the conditions of 50°C and a vacuum of 1 kPaA. h, wherein the tail gas containing 3-chloropropene contains 3 vol.% 3-chloropropene, 3 vol.% oxygen and 94 vol.% nitrogen; the adsorption bed in the adsorption separation unit 2 is 500 kg of molecular sieve-based adsorption material prepared in Example 5; in the tail gas after adsorption treatment, the nitrogen content is 96.9 vol.%, the 3-chloropropene content is 0.1 vol.%, and the oxygen content is 3 vol.%; in the nitrogen-containing mixed gas obtained after deoxygenation treatment, the nitrogen content is 99.6 vol.%, the 3-chloropropene content is 0.1 vol.%, and the oxygen content is 0.3 vol.%; the gas from the desulfurization unit 5 and the dilution gas have the same composition, specifically, nitrogen with a purity of 99.99 wt%, used to replenish the loss of dilution gas during the circulation process.

[0086] Example 6

[0087] Preparation of molecular sieve-based adsorbent materials:

[0088] 100g of silica gel and 15g of tetrapropylammonium bromide were stirred at 60 rpm and 35°C for 5 min to disperse them in 100mL of water. 5g of caustic soda and 5g of ammonium fluoride were added, and the mixture was stirred at 50 rpm and 15°C for 30 min to obtain a gel. The gel was transferred to a stainless steel crystallization vessel lined with polytetrafluoroethylene (PTFE) and crystallized at 50 rpm and 180°C for 48 h. The crystallized material was rinsed with water and dried at 90°C for 10 h, followed by calcination at 550°C for 5 h.

[0089] Treatment of tail gas from the hydrogen peroxide method for epichlorohydrin production: The prepared molecular sieve-based adsorbent material is loaded into the adsorption separation unit 2 as an adsorption bed. The product from the hydrogen peroxide method for epichlorohydrin production and the dilution gas are transported to the gas-liquid separation device 1 for separation. The tail gas containing 3-chloropropene separated by the gas-liquid separation device 1 is transported to the adsorption separation unit 2 at a rate of 50 kg / h for adsorption treatment. Then, the adsorbed tail gas is transported to the deoxygenation unit 3 for deoxygenation treatment. The nitrogen-containing mixed gas obtained after deoxygenation treatment is mixed with the gas from the desulfurization device 5 and then pressurized to 0.8 MPa by the pressure control unit 4 before being returned to the gas-liquid separation device 1 for recycling. After the adsorption bed has completed adsorption, 3-chloropropene is recovered for 5 hours at a temperature of 80°C and a vacuum of 20 kPa. The tail gas containing 3-chloropropene contains 7 vol.% 3-chloropropene, 3 vol.% oxygen, and 90 vol.% nitrogen. The adsorption bed in the adsorption separation unit 2 is 500 kg of the molecular sieve-based adsorption material prepared in Example 6. In the tail gas after adsorption treatment, the nitrogen content is 96.5 vol.%, the 3-chloropropene content is 0.5 vol.%, and the oxygen content is 3 vol.%. In the nitrogen-containing mixed gas obtained after deoxygenation treatment, the nitrogen content is 99.7 vol.%, the 3-chloropropene content is 0.5 vol.%, and the oxygen content is 0.2 vol.%. The gas from the desulfurization unit 5 and the dilution gas have the same composition, specifically, each is nitrogen with a purity of 99.99 wt%, used to replenish the loss of the dilution gas during the circulation process.

[0090] Example 7

[0091] Preparation of molecular sieve-based adsorbent materials:

[0092] 100g of silica gel and 100g of tetrapropylammonium bromide were stirred at 60 rpm and 0°C for 60 min to disperse them in 200 mL of water. 35g of caustic soda and 10g of ammonium fluoride were added, and the mixture was stirred at 50 rpm and 35°C for 100 min to obtain a gel. The gel was transferred to a stainless steel crystallization vessel lined with polytetrafluoroethylene (PTFE) and crystallized at 5 rpm and 180°C for 48 h. The crystallized material was rinsed with water and dried at 70°C for 10 h, followed by calcination at 550°C for 5 h.

[0093] Treatment of tail gas from the hydrogen peroxide method for epichlorohydrin production: The prepared molecular sieve-based adsorbent material is packed into the adsorption separation unit 2 as an adsorption bed. The product from the hydrogen peroxide method for epichlorohydrin production and the dilution gas are transported to the gas-liquid separation device 1 for separation. The tail gas containing 3-chloropropene separated by the gas-liquid separation device 1 is transported to the adsorption separation unit 2 at a rate of 50 kg / h for adsorption treatment. Then, the adsorbed tail gas is transported to the deoxygenation unit 3 for deoxygenation treatment. The nitrogen-containing mixed gas obtained after deoxygenation treatment is mixed with the gas from the desulfurization device 5 and then pressurized to 0.8 MPa by the pressure control unit 4 before being returned to the gas-liquid separation device 1 for recycling. After the adsorption bed has completed adsorption, 3-chloropropene is recovered under conditions of 100°C and a vacuum of 20 kPaA. h, wherein the tail gas containing 3-chloropropene contains 3 vol.% 3-chloropropene, 2 vol.% oxygen and 95 vol.% nitrogen; the adsorption bed in the adsorption separation unit 2 is 500 kg of molecular sieve-based adsorption material prepared in Example 7; in the tail gas after adsorption treatment, the nitrogen content is 97.8 vol.%, the 3-chloropropene content is 0.2 vol.%, and the oxygen content is 2 vol.%; in the nitrogen-containing mixed gas obtained after deoxygenation treatment, the nitrogen content is 99.6 vol.%, the 3-chloropropene content is 0.2 vol.%, and the oxygen content is 0.2 vol.%; the gas from the desulfurization unit 5 and the dilution gas have the same composition, specifically, nitrogen with a purity of 99.99 wt%, used to replenish the loss of dilution gas during the circulation process.

[0094] Comparative Example 1

[0095] The adsorbent material was prepared according to the method in Example 1, except that 100 mL of water was replaced with 1000 mL of water.

[0096] Treatment of tail gas from the hydrogen peroxide method for producing epichlorohydrin: The prepared adsorbent material is loaded into the adsorption separation unit 2 as an adsorption bed. The product from the hydrogen peroxide method for producing epichlorohydrin and the dilution gas are transported to the gas-liquid separation device 1 for separation. The tail gas containing 3-chloropropene separated by the gas-liquid separation device 1 is transported to the adsorption separation unit 2 at a rate of 50 kg / h for adsorption treatment. Then, the adsorbed tail gas is transported to the deoxygenation unit 3 for deoxygenation treatment. The nitrogen-containing mixed gas obtained after deoxygenation treatment is mixed with the gas from the desulfurization device 5 and then pressurized to 0.8 MPa by the pressure control unit 4 before being returned to the gas-liquid separation device 1 for recycling. After the adsorption bed has completed adsorption, 3-chloropropene is recovered under conditions of 50°C and a vacuum of 20 kPaA. The tail gas containing 3-chloropropene contains 3 vol.% 3-chloropropene, 2 vol.% oxygen, and 95 vol.% nitrogen; the adsorption bed in the adsorption separation unit 2 is 500 kg of molecular sieve-based adsorption material prepared in Comparative Example 1; in the tail gas after adsorption treatment, the nitrogen content is 95.4 vol.%, the 3-chloropropene content is 2.6 vol.%, and the oxygen content is 2 vol.%; in the nitrogen-containing mixed gas obtained after deoxygenation treatment, the nitrogen content is 97.1 vol.%, the 3-chloropropene content is 2.6 vol.%, and the oxygen content is 0.3 vol.%; the gas from the desulfurization unit 5 and the dilution gas have the same composition, specifically, each is nitrogen with a purity of 99.99 wt%, used to replenish the loss of the dilution gas during the circulation process.

[0097] Comparative Example 2

[0098] The adsorbent material was prepared according to the method of Example 1, except that ammonium fluoride was not added.

[0099] Treatment of tail gas from the hydrogen peroxide method for producing epichlorohydrin: The prepared adsorbent material is loaded into the adsorption separation unit 2 as an adsorption bed. The product from the hydrogen peroxide method for producing epichlorohydrin and the dilution gas are transported to the gas-liquid separation device 1 for separation. The tail gas containing 3-chloropropene separated by the gas-liquid separation device 1 is transported to the adsorption separation unit 2 at a rate of 50 kg / h for adsorption treatment. Then, the adsorbed tail gas is transported to the deoxygenation unit 3 for deoxygenation treatment. The nitrogen-containing mixed gas obtained after deoxygenation treatment is mixed with the gas from the desulfurization device 5 and then pressurized to 0.8 MPa by the pressure control unit 4 before being returned to the gas-liquid separation device 1 for recycling. After the adsorption bed has completed adsorption, 3-chloropropene is recovered under conditions of 50°C and a vacuum of 20 kPaA. The tail gas containing 3-chloropropene contains 3 vol.% 3-chloropropene, 2 vol.% oxygen, and 95 vol.% nitrogen; the adsorption bed in the adsorption separation unit 2 is 500 kg of molecular sieve-based adsorption material prepared in Comparative Example 2; in the tail gas after adsorption treatment, the nitrogen content is 96.9 vol.%, the 3-chloropropene content is 1.0 vol.%, and the oxygen content is 2.1 vol.%; in the nitrogen-containing mixed gas obtained after deoxygenation treatment, the nitrogen content is 98.9 vol.%, the 3-chloropropene content is 1.0 vol.%, and the oxygen content is 0.1 vol.%; the gas from the desulfurization unit 5 and the dilution gas have the same composition, specifically, each is nitrogen with a purity of 99.99 wt%, used to replenish the loss of the dilution gas during the circulation process.

[0100] Comparative Example 3

[0101] The adsorbent material was prepared according to the method of Example 1, except that caustic soda was not added.

[0102] Treatment of tail gas from the hydrogen peroxide method for producing epichlorohydrin: The prepared adsorbent material is loaded into the adsorption separation unit 2 as an adsorption bed. The product from the hydrogen peroxide method for producing epichlorohydrin and the dilution gas are transported to the gas-liquid separation device 1 for separation. The tail gas containing 3-chloropropene separated by the gas-liquid separation device 1 is transported to the adsorption separation unit 2 at a rate of 50 kg / h for adsorption treatment. Then, the adsorbed tail gas is transported to the deoxygenation unit 3 for deoxygenation treatment. The nitrogen-containing mixed gas obtained after deoxygenation treatment is mixed with the gas from the desulfurization device 5 and then pressurized to 0.8 MPa by the pressure control unit 4 before being returned to the gas-liquid separation device 1 for recycling. After the adsorption bed has completed adsorption, 3-chloropropene is recovered under conditions of 50°C and a vacuum of 20 kPaA. The tail gas containing 3-chloropropene contains 3 vol.% 3-chloropropene, 2 vol.% oxygen, and 95 vol.% nitrogen; the adsorption bed in the adsorption separation unit 2 is 500 kg of molecular sieve-based adsorption material prepared in Comparative Example 3; in the tail gas after adsorption treatment, the nitrogen content is 95.5 vol.%, the 3-chloropropene content is 2.5 vol.%, and the oxygen content is 2 vol.%; in the nitrogen-containing mixed gas obtained after deoxygenation treatment, the nitrogen content is 97.3 vol.%, the 3-chloropropene content is 2.5 vol.%, and the oxygen content is 0.2 vol.%; the gas from the desulfurization unit 5 and the dilution gas have the same composition, specifically, each is nitrogen with a purity of 99.99 wt%, used to replenish the loss of the dilution gas during the circulation process.

[0103] Comparative Example 4

[0104] The adsorbent material was prepared according to the method of Example 1, except that caustic soda and ammonium fluoride were not added.

[0105] Treatment of tail gas from the hydrogen peroxide method for producing epichlorohydrin: The prepared adsorbent material is loaded into the adsorption separation unit 2 as an adsorption bed. The product from the hydrogen peroxide method for producing epichlorohydrin and the dilution gas are transported to the gas-liquid separation device 1 for separation. The tail gas containing 3-chloropropene separated by the gas-liquid separation device 1 is transported to the adsorption separation unit 2 at a rate of 50 kg / h for adsorption treatment. Then, the adsorbed tail gas is transported to the deoxygenation unit 3 for deoxygenation treatment. The nitrogen-containing mixed gas obtained after deoxygenation treatment is mixed with the gas from the desulfurization device 5 and then pressurized to 0.8 MPa by the pressure control unit 4 before being returned to the gas-liquid separation device 1 for recycling. After the adsorption bed has completed adsorption, 3-chloropropene is recovered under conditions of 50°C and a vacuum of 20 kPaA. The tail gas containing 3-chloropropene contains 3 vol.% 3-chloropropene, 2 vol.% oxygen, and 95 vol.% nitrogen; the adsorption bed in the adsorption separation unit 2 is 500 kg of molecular sieve-based adsorption material prepared in Comparative Example 4; in the tail gas after adsorption treatment, the nitrogen content is 95.3 vol.%, the 3-chloropropene content is 2.7 vol.%, and the oxygen content is 2 vol.%; in the nitrogen-containing mixed gas obtained after deoxygenation treatment, the nitrogen content is 97.1 vol.%, the 3-chloropropene content is 2.7 vol.%, and the oxygen content is 0.2 vol.%; the gas from the desulfurization unit 5 and the dilution gas have the same composition, specifically, each is nitrogen with a purity of 99.99 wt%, used to replenish the loss of the dilution gas during the circulation process.

[0106] As can be seen from the above examples and comparative examples, compared with comparative examples 1-4, the molecular sieve-based adsorbent materials prepared in examples 3-7 have high selectivity for 3-chloropropene adsorption and recovery, but low selectivity for nitrogen and oxygen, thus achieving the recovery and utilization of 3-chloropropene species; in the treatment of tail gas from the hydrogen peroxide process for epichlorohydrin production, it can significantly reduce the loss of 3-chloropropene material and nitrogen consumption. Figure 3 It can be seen that the molecular sieve-based adsorbent material described in this invention is a molecular sieve-type porous material with an MFI topology and no other impurities.

[0107] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for preparing a molecular sieve-based adsorbent material, characterized in that, The method includes: dispersing a silicon source and tetrapropylammonium bromide in water, mixing the resulting mixture with an inorganic base and ammonium fluoride to obtain a gel, and then sequentially crystallizing and calcining the gel. The amount of water used is 100-250 parts by weight relative to 100 parts by weight of the silicon source.

2. The method according to claim 1, characterized in that, The amount of tetrapropylammonium bromide used relative to 100 parts by weight of the silicon source is 10-120 parts by weight, the amount of the inorganic base is 5-40 parts by weight, and the amount of ammonium fluoride is 5-15 parts by weight.

3. The method according to claim 1 or 2, characterized in that, The inorganic base is caustic soda and / or sodium carbonate.

4. The method according to any one of claims 1-3, characterized in that, The silicon source is silica gel and / or silica.

5. The method according to any one of claims 1-4, characterized in that, The crystallization conditions include a temperature of 150-200℃ and a time of 48-150h.

6. The method according to any one of claims 1-5, characterized in that, The roasting conditions include a temperature of 450-650℃ and a time of 4-7 hours.

7. A molecular sieve-based adsorbent material prepared by the method according to any one of claims 1-6.

8. A method for adsorption and recovery of 3-chloropropene, the method comprising: The tail gas containing 3-chloropropene is contacted with an adsorbent material, characterized in that the adsorbent material is the molecular sieve-based adsorbent material as described in claim 7.

9. The method according to claim 8, characterized in that, The exhaust gas containing 3-chloropropene contains 0.1-8 vol.% 3-chloropropene and 0.5-3 vol.% oxygen.

10. The method according to claim 9, characterized in that, The tail gas containing 3-chloropropene is first processed in an adsorption separation unit and then in a deoxygenation unit. The adsorption material is packed in the adsorption separation unit as an adsorption bed.

11. A method for treating the tail gas from the hydrogen peroxide process for producing epichlorohydrin, characterized in that, The method includes: transporting the product of epichlorohydrin produced by hydrogen peroxide method and dilution gas to a gas-liquid separation device (1) for separation treatment; transporting the tail gas containing 3-chloropropene separated by the gas-liquid separation device (1) to an adsorption separation unit (2) for adsorption treatment; and then transporting the tail gas after adsorption treatment to a deoxygenation unit (3) for deoxygenation treatment, wherein the adsorption bed in the adsorption separation unit (2) is the molecular sieve-based adsorption material as described in claim 7.

12. The method according to claim 11, characterized in that, The method further includes: pressurizing the mixed gas containing dilution gas obtained after deoxygenation treatment and returning it to the gas-liquid separation device (1) for recycling.

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