Sulfonic acid anion hybrid porous material and preparation method, ethylene ethane separation method

Abstract

The present invention discloses a sulfonic acid anion hybrid porous material and a preparation method, and an ethylene ethane separation method. The separation method uses a sulfonic acid anion hybrid porous material to achieve ethylene ethane separation. The sulfonic acid anion hybrid porous material comprises: the sulfonic acid anion hybrid porous material is composed of a sulfonic acid anion S, an organic ligand L and a metal cation M through a coordination bond, and its chemical formula is [MSL 2 ] n , where n is a positive integer, indicating that the material consists of several components: MSL 2 The structural unit is expanded in space; the sulfonate anion is ethanedisulfonate anion or butanedisulfonate anion; the metal cation is Cu 2+ 、Zn 2+ 、Co 2+ The organic ligand is one of 4,4'-bipyridine, 1,2,4-triazole, and 4,4'-bipyridine disulfide. The sulfonic acid anion hybrid porous material can efficiently separate ethylene and ethane at room temperature and mild operating conditions, and the separated ethylene has higher purity and significantly reduces energy consumption.

Description

Technical Field

[0001] The invention relates to the technical field of chemical separation, and in particular to a sulfonic acid anion hybrid porous material and a preparation method thereof, and an ethylene ethane separation method. Background Art

[0002] As the cornerstone of petrochemical industry, ethylene is one of the most produced chemicals in the world. Its downstream products mainly include polyethylene, polyvinyl chloride, ethylene oxide, ethylene glycol, vinyl acetate, etc., accounting for more than 75% of petrochemical products, and are widely used in various national economic industries such as plastics, pharmaceuticals, textiles, and coatings. At present, my country mainly produces ethylene by cracking naphtha, among which the separation of ethylene and ethane is a key step in the preparation of high-purity ethylene. Refinery dry gas also contains abundant ethylene resources, and the separation of ethylene and ethane is also a key technology in the efficient utilization of refinery dry gas. However, the structural properties of ethylene and ethane are highly similar, with only slight differences in unsaturation, which makes ethylene / ethane separation difficult and energy-intensive.

[0003] The separation technologies of ethylene and ethane mainly include cryogenic distillation, solvent absorption, membrane separation and adsorption separation. Among them, cryogenic distillation technology is the most mature and widely used in industry. However, due to the close boiling points of ethylene and ethane and the low relative volatility, they need to be separated under higher pressure (~22bar), extremely low temperature (~-160℃) and large reflux ratio. In addition, the number of plates in the distillation tower usually exceeds 150, which has the disadvantages of high energy consumption and large equipment investment. The solvent absorption method not only has the problem of large organic solvent pollution, but also has low selectivity. The membrane separation method is limited in its industrial application due to the low selectivity of existing membranes, the complex membrane manufacturing process and high cost. As a low-energy, environmentally friendly separation technology, adsorption separation technology is suitable for the separation of substances with similar structures, such as the separation and purification of low-carbon hydrocarbon gases, and has great advantages over several other separation technologies. Summary of the invention

[0004] The inventors have found that when using adsorption separation technology to separate substances with similar structures such as ethylene and ethane, existing adsorption materials, such as zeolite molecular sieves, activated carbon, polymers, metal organic framework materials, etc., often find it difficult to accurately identify the tiny differences between ethylene and ethane molecules, and have the disadvantages of low separation selectivity, small adsorption capacity, and poor stability, which restricts the feasibility of ethylene / ethane adsorption separation technology. For example:

[0005] Although the adsorption capacity of 4A molecular sieve can reach 2.7mmol·g at 1bar and 25℃ -1 , but it has the disadvantages of low selectivity and high desorption heat.

[0006] "Olefin / Paraffin Separations by Adsorption: π-Complexation vs. Kinetic Separation" (AIChE JOURNAL, 2004, 44(4): 799-809.) discloses the use of carbon molecular sieves to achieve ethylene and ethane separation, but its ethylene capacity at 1 bar and 25 ° C is only 1.1 mmol·g -1 .

[0007] "Control of zeolite framework flexibility and pore topology for separation of ethane and ethylene" (Science, 2017, 358(6366):1068-1071.) discloses a new molecular sieve ITQ-55 for ethylene and ethane separation. It shows good ethylene / ethane kinetic separation performance, but its ethylene adsorption capacity is low due to its small pore size, which is only 1.5 mmol·g at 1 bar and 30°C. -1 .

[0008] The Chinese patent application with publication number CN1073422A, published on June 23, 1993, entitled "Process for separation of ethylene by adsorption from catalytic cracking dry gas" and the Chinese patent application with publication (announcement) number CN1048010C, published on June 3, 1998, entitled "Method for recovering ethylene from dilute ethylene-containing gas" disclose the use of Ag + / Cu + Supported molecular sieves separate ethylene, but Ag + / Cu + Loaded molecular sieves are sensitive to moisture, sulfide, etc. in the raw gas. At the same time, they have strong interactions with guest molecules and are not easy to desorb, which is not conducive to industrial applications.

[0009] As an emerging porous adsorption material, metal-organic framework materials have outstanding advantages such as large specific surface area, high pore volume, easy chemical modification of pores and precise adjustment of pore size. However, the separation performance of π-complexed framework materials widely studied for mixed gases still needs to be improved. For example, "Hydrocarbon Separations in a Metal-Organic Framework with Open Iron(II) Coordination Sites" (Science, 2012, 335(6076):1606-1610.) discloses the metal-organic framework material Fe-MOF-74, which has a high density of unsaturated metal sites that can generate electrostatic interactions with the π electrons of the double bond of ethylene. However, due to the large pore size (~11Å), the selectivity for ethylene / ethane mixed gases is low. At the same time, there are disadvantages such as harsh synthesis conditions (must be synthesized by hydrothermal reaction under inert gas protection) and poor stability.

[0010] It can be seen that the adsorption materials that can be used for ethylene and ethane separation in the existing technology cannot have high adsorption capacity, high selectivity and high stability at the same time. The design and preparation of new porous materials with high adsorption capacity, high selectivity and high stability are crucial for the development of ethylene and ethane adsorption separation technology.

[0011] In view of the above problems, the present invention is proposed to provide a sulfonic acid anion hybrid porous material and a preparation method, and an ethylene ethane separation method that overcome the above problems or at least partially solve the above problems.

[0012] The embodiment of the present invention provides a sulfonic acid anion hybrid porous material, comprising:

[0013] The sulfonic acid anion hybrid porous material is composed of sulfonic acid anions S, organic ligands L and metal cations M through coordination bonds, and its chemical formula is [MSL2] n , wherein n is a positive integer, indicating that the material is formed by a plurality of structural units composed of MSL2 extending in space;

[0014] The sulfonate anion is an ethanedisulfonate anion or a butanedisulfonate anion;

[0015] The metal cation is Cu 2+ 、Zn 2+ 、Co 2+ One of;

[0016] The organic ligand is one of 4,4'-bipyridine, 1,2,4-triazole and 4,4'-bipyridine disulfide.

[0017] In some optional embodiments, the organic ligands are coordinated to the metal cations via nitrogen atoms, and the organic ligands are all di-coordinated; the sulfonate anions are coordinated to the metal cations via oxygen atoms, and each sulfonate anion is connected to two different metal cations; each metal cation is connected to four different organic ligands and coordinated to two oxygen atoms.

[0018] The embodiment of the present invention provides a method for preparing a sulfonic acid anion hybrid porous material, comprising: using a metal ion inorganic salt, a sulfonic acid anion compound and an organic ligand compound in a molar ratio of 1:(0.5-3):(1-5) to prepare a sulfonic acid anion hybrid porous material.

[0019] In some optional embodiments, the sulfonic acid anion hybrid porous material is prepared by using a metal ion inorganic salt, a sulfonic acid anion compound and an organic ligand compound in a molar ratio of 1:(0.5-3):(1-5), including:

[0020] Using metal ion inorganic salt, sulfonic acid anion compound and organic ligand compound in a molar ratio of 1: (0.5-3): (1-5) to prepare a sulfonic acid anion hybrid porous material liquid product;

[0021] Vacuum-filtering the sulfonic acid anion hybrid porous material liquid product at 25° C. to obtain a sulfonic acid anion hybrid porous material solid product;

[0022] The solid sulfonic acid anion hybrid porous material is activated under vacuum conditions at 100° C. or by inert gas purging to remove guest solvent molecules in the pores, thereby obtaining the sulfonic acid anion hybrid porous material.

[0023] In some optional embodiments, the use of metal ion inorganic salt, sulfonic acid anion compound and organic ligand compound in a molar ratio of 1: (0.5-3): (1-5) to prepare a sulfonic acid anion hybrid porous material liquid product includes:

[0024] Dissolving a metal ion inorganic salt, a sulfonic acid anion compound and an organic ligand compound in water at a molar ratio of 1:(0.5-3):(1-5), stirring at room temperature until the reaction is completed or maintaining a specified heating temperature until the reaction is completed, to obtain a sulfonic acid anion hybrid porous material liquid product;

[0025] A metal ion inorganic salt and a sulfonic acid anion compound are dissolved in water or an organic solvent to obtain a solution 1, and an organic ligand compound is dissolved in water or an organic solvent to obtain a solution 2, wherein the metal ion inorganic salt, the sulfonic acid anion compound and the organic ligand compound are in a molar ratio of 1:(0.5-3):(1-5); the solution 2 is added dropwise to the solution 1 and allowed to stand and diffuse until the reaction is completed, or the solution 1 and the solution 2 are mixed and stirred at room temperature until the reaction is completed or maintained at a specified heating temperature until the reaction is completed, to obtain a sulfonic acid anion hybrid porous material liquid product.

[0026] In some optional embodiments, the stirring at room temperature until the reaction is completed includes: stirring at room temperature for no less than 12 hours.

[0027] In some optional embodiments, maintaining the specified heating temperature until the reaction is completed includes: heating to 80° C. and maintaining it for 3 days.

[0028] In some optional embodiments, after obtaining the sulfonic acid anion hybrid porous material solid product and before activating it, the process further comprises: washing with water or methanol for multiple times and soaking for 8 to 50 hours.

[0029] In some optional embodiments, the metal ion inorganic salt is a metal ion chloride or nitrate compound;

[0030] The sulfonic acid anion compound is one of sodium ethanedisulfonate and sodium butanedisulfonate;

[0031] The organic ligand compound is one of 4,4'-bipyridine, 1,2,4-triazole and 4,4'-bipyridine disulfide.

[0032] In some optional embodiments, the metal ion chloride is cobalt chloride, and the nitric acid compound is one of copper nitrate, zinc nitrate, and cobalt nitrate.

[0033] An embodiment of the present invention provides an ethylene ethane separation method, comprising: using the above-mentioned sulfonic acid anion hybrid porous material to achieve ethylene ethane separation.

[0034] In some optional embodiments, the above method includes:

[0035] A mixed gas containing ethylene and ethane is brought into contact with the sulfonic acid anion hybrid porous material, and the sulfonic acid anion hybrid porous material adsorbs the ethylene to separate the ethane.

[0036] In some optional embodiments, the above method further includes:

[0037] The sulfonic acid anion hybrid porous material adsorbing ethylene is subjected to a desorption treatment to obtain ethylene.

[0038] In some optional embodiments, the step of contacting the mixed gas containing ethylene and ethane with the sulfonic acid anion hybrid porous material comprises:

[0039] The mixed gas containing ethylene and ethane is brought into contact with the sulfonic acid anion hybrid porous material through at least one of fixed bed adsorption and moving bed adsorption.

[0040] In some optional embodiments, a mixed gas containing ethylene and ethane is brought into contact with a sulfonic acid anion hybrid porous material by fixed bed adsorption to separate ethane, comprising:

[0041] A mixed gas containing ethylene and ethane enters a fixed bed at a set flow rate under a set adsorption temperature and adsorption pressure, and contacts with a sulfonic acid anion hybrid porous material in a fixed bed adsorption column to adsorb ethylene, and obtains a gas containing ethane at the outlet of the adsorption column;

[0042] When ethylene appears at the outlet of the adsorption column, or the concentration gradient front of ethylene in the bed is not lower than the set proportion of the bed, stop the mixed gas input.

[0043] In some optional embodiments, the sulfonic acid anion hybrid porous material adsorbing ethylene is subjected to a desorption treatment to obtain ethylene, comprising:

[0044] At a set desorption temperature and desorption pressure, the ethylene adsorbed by the sulfonic acid anion hybrid porous material in the fixed bed adsorption column is desorbed to obtain ethylene at the outlet of the adsorption column; or

[0045] At the set desorption temperature and desorption pressure, the ethylene adsorbed by the sulfonic acid anion hybrid porous material in the fixed bed adsorption column is desorbed, and pure ethylene is introduced for reverse replacement to obtain ethylene at the outlet of the adsorption column.

[0046] In some optional embodiments, the adsorption temperature is -30~100°C, the adsorption pressure is 1~10 bar, the desorption temperature is 0~120°C, and the desorption pressure is 0.01~1 bar.

[0047] In some optional embodiments, the adsorption temperature is 25-40° C., the adsorption pressure is 1-5 bar, the desorption temperature is 60-100° C., and the desorption pressure is 0.01-0.1 bar.

[0048] In some optional embodiments, the set flow rate is 0.5~10.0mL / min.

[0049] In some optional embodiments, the mixed gas contains 10% to 90% ethylene, 10% to 90% ethane, and 0% to 20% impurity gas.

[0050] The embodiment of the present invention also provides an application of a sulfonic acid anion hybrid porous material in an ethylene ethane separation method.

[0051] The beneficial effects of the above technical solution provided by the embodiment of the present invention include at least:

[0052] The sulfonic acid anion hybrid porous material provided by the embodiment of the present invention is composed of different sulfonic acid anions S, organic ligands L and metal cations M through coordination bonds, and its structural unit can be expanded in space. The sulfonic acid anion hybrid porous material obtained by combining different metal cations, organic ligands and sulfonic acid anions has both suitable pore size and flexibility. When in contact with gas, the pores can be deformed to allow gas molecules to pass through. For ethylene with a smaller kinetic size, the diffusion rate of ethylene in the sulfonic acid anion hybrid porous material is significantly faster than that of ethane, thereby achieving efficient separation of ethylene / ethane mixed gas; and compared with the existing materials for ethylene and ethane separation, the material has a milder interaction with gas molecules, and the material is easier to regenerate after the adsorbed gas is desorbed, and can be reused many times; the material introduces sulfonic acid anions as anion action sites and pillaring ligands, has stronger recognition ability, and better ability to adjust the pore structure and size.

[0053] Sulfonic acid anion hybrid porous materials are made of widely available and inexpensive raw materials, with mild synthesis conditions, simple methods, good reproducibility, good water and thermal stability, and long service life. At the same time, the separation performance is less affected by moisture, sulfide, etc.

[0054] This material is used for ethylene and ethane separation, and can achieve efficient separation of ethylene and ethane at room temperature and pressure. Compared with the low-temperature distillation method widely used in current industrial production, it has mild operating conditions and significantly reduced energy consumption, which is more in line with the concept of sustainable development. At the same time, it has outstanding advantages such as small equipment investment and has good prospects for industrial application.

[0055] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings.

[0056] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0058] Figure 1This is a flow chart of the ethylene ethane separation method according to an embodiment of the present invention;

[0059] Figure 2 The flowchart of the method for preparing the sulfonic acid anion hybrid porous material in an embodiment of the present invention is shown in FIG. DETAILED DESCRIPTION

[0060] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0061] The embodiment of the present invention provides a sulfonic acid anion hybrid porous material, which is composed of a sulfonic acid anion S, an organic ligand L and a metal cation M through a coordination bond, and its chemical formula is [MSL2] n , wherein n is a positive integer, indicating that the material is formed by a plurality of structural units composed of MSL2 extending in space;

[0062] The sulfonate anion is an ethanedisulfonate anion or a butanedisulfonate anion;

[0063] The metal cation is Cu 2+ 、Zn 2+ 、Co 2+ One of;

[0064] The organic ligand is one of 4,4'-bipyridine, 1,2,4-triazole and 4,4'-bipyridine disulfide.

[0065] Among them, the organic ligands are coordinated with the metal cations through nitrogen atoms, and the organic ligands are all di-coordinated; the sulfonate anions are coordinated with the metal cations through oxygen atoms, and each sulfonate anion is connected to two different metal cations; each metal cation is connected to four different organic ligands and coordinated with two oxygen atoms.

[0066] The present invention also provides a method for separating ethylene and ethane, using the above-mentioned sulfonic acid anion hybrid porous material to achieve the separation of ethylene and ethane. The process is as follows Figure 1 As shown, the following steps are included:

[0067] Step S101: a mixed gas containing ethylene and ethane is brought into contact with a sulfonic acid anion hybrid porous material, and the sulfonic acid anion hybrid porous material adsorbs ethylene to separate ethane.

[0068] The mixed gas of ethylene and ethane may contain one or more impurity gases such as methane, oxygen, nitrogen, hydrogen, carbon monoxide, etc. The volume ratio of impurity gas to ethylene and ethane is: ethylene component is 10%~90%, ethane component is 10%~90%, and impurity gas is 0~20%. For example, ethylene: ethane: methane = 50:40:10. Within this ratio range, the impurity gas has little effect on the ethylene / ethane separation performance of the sulfonic acid anion hybrid porous material. Of course, separation can also be performed within other ratio ranges.

[0069] Step S102: Desorbing the sulfonic acid anion hybrid porous material that has adsorbed ethylene to obtain ethylene.

[0070] In the above step S101, the mixed gas containing ethylene and ethane is brought into contact with the sulfonic acid anion hybrid porous material by at least one of fixed bed adsorption and moving bed adsorption, and the sulfonic acid anion hybrid porous material adsorbs ethylene to separate ethane.

[0071] Fixed bed adsorption can be achieved through a fixed bed adsorber. A fixed bed adsorber refers to an adsorption device in which the adsorbent is fixed at certain parts of the adsorber. When the airflow passes through the adsorbent bed, the adsorbent remains stationary. It has a simple structure and is easy to operate, and is widely used.

[0072] In some optional embodiments, a mixed gas containing ethylene and ethane is brought into contact with a sulfonic acid anion hybrid porous material by fixed bed adsorption to separate ethane, comprising: allowing the mixed gas containing ethylene and ethane to enter a fixed bed at a set flow rate under a set adsorption temperature and pressure, and bringing the mixed gas into contact with the sulfonic acid anion hybrid porous material in a fixed bed adsorption column to adsorb ethylene, and obtaining a gas containing ethane at an outlet of the adsorption column; when ethylene appears at the outlet of the adsorption column, or when the concentration gradient front of ethylene in the bed is not lower than a set proportion of the bed, stopping the input of the mixed gas.

[0073] When the contact mode between the mixed gas and the sulfonic acid anion hybrid porous material is a fixed bed adsorption mode:

[0074] A mixed gas containing ethylene and ethane is passed into a fixed bed adsorption column filled with a sulfonic acid anion hybrid porous material at a constant adsorption pressure and temperature to contact the sulfonic acid anion hybrid porous material. The diffusion rate of the ethane component is slow and the adsorption amount is lower than that of the ethylene component. The ethane component preferentially penetrates the fixed bed adsorption column to obtain ethane gas at the outlet of the adsorption column. After the ethane component penetrates, the mixed gas is continuously introduced for adsorption. The adsorption lasts for a certain period of time so that the concentration gradient front of ethylene in the bed is not less than 2 / 3 of the bed. When the ethylene component penetrates, the introduction of the mixed gas is stopped. The temperature and pressure are adjusted to a preset desorption temperature and desorption pressure by one of the methods of heating and reducing pressure or a combination of multiple methods to perform desorption. The ethylene is further concentrated by purging and replacement with high-purity ethylene to obtain ethylene gas. The ethylene used for purging and replacement can be high-purity ethylene obtained by desorption or ethylene obtained by other means.

[0075] By using the sulfonic acid anion hybrid porous material and the fixed bed adsorption process, ethylene gas with a purity of 85-99% can be separated from a mixed gas containing ethylene and ethane.

[0076] In order to improve the purity of ethylene, it is also possible to consider using a multi-bed pressure swing adsorption process or a multiple fixed bed adsorption method. In the multi-bed pressure swing adsorption, ethylene is more fully adsorbed by using multiple fixed beds, using different adsorption and desorption pressures, or using multiple fixed beds for sequential adsorption, so as to separate ethylene and ethane with better purity. Multiple fixed bed adsorption uses a fixed bed and cycles through it for multiple adsorptions.

[0077] Moving bed adsorption can be achieved through a moving bed adsorber. A moving bed adsorber refers to a device in which the adsorbent follows the flow of the airflow during the adsorption process to complete the adsorption. In this type of adsorber, fresh adsorbent is added from the top of the tower, and the adding rate is based on the principle of maintaining a certain contact height between the gas and solid phases. There is a device at the bottom of the tower to continuously remove the saturated adsorbent and send it to another container for regeneration, and then return it to the top of the tower after regeneration.

[0078] In the above step S102, an optional process of desorption treatment may include: desorbing ethylene adsorbed by the sulfonic acid anion hybrid porous material in the fixed bed adsorption column at a set desorption temperature and desorption pressure, and obtaining ethylene at the outlet of the adsorption column.

[0079] Another optional process of desorption treatment may include: desorbing ethylene adsorbed by the sulfonic acid anion hybrid porous material in the fixed bed adsorption column at a set desorption temperature and desorption pressure, and introducing pure ethylene for reverse replacement to obtain ethylene at the outlet of the adsorption column.

[0080] Optionally, the adsorption temperature is -30~100°C, the adsorption pressure is 1~10 bar, the desorption temperature is 0~120°C, and the desorption pressure is 0.01~1 bar. Preferably, the adsorption temperature is 25~40°C, the adsorption pressure is 1~5 bar, the desorption temperature is 60~100°C, and the desorption pressure is 0.01~0.1 bar.

[0081] The optional set flow rate is 0.5~10.0mL / min.

[0082] The method for separating ethylene and ethane provided in an embodiment of the present invention is an adsorption separation method, which can achieve efficient separation of ethylene and ethane under mild operating conditions. The mixed gas of ethylene and ethane is contacted with a sulfonic acid anion hybrid porous material, and the sulfonic acid anion hybrid porous material preferentially adsorbs ethylene in the mixed gas to achieve separation of ethylene and ethane. The present invention introduces sulfonic acid anions and accurately controls the pore size and pore surface properties of the ion hybrid porous material, so that ethylene is highly selectively adsorbed in the pores, thereby achieving efficient separation of ethylene and ethane. The method has outstanding advantages such as good material stability and high adsorption selectivity, and has good industrial application prospects.

[0083] The embodiment of the present invention also provides a method for preparing a sulfonic acid anion hybrid porous material, comprising: using a metal ion inorganic salt, a sulfonic acid anion compound and an organic ligand compound in a molar ratio of 1:(0.5-3):(1-5) to prepare a sulfonic acid anion hybrid porous material.

[0084] In some optional embodiments, the process of the above preparation method is as follows Figure 1 As shown, the following steps are included:

[0085] Step S201: using metal ion inorganic salt, sulfonic acid anion compound and organic ligand compound in a molar ratio of 1:(0.5-3):(1-5) to prepare a sulfonic acid anion hybrid porous material liquid product.

[0086] Optionally, the metal ion inorganic salt is a metal ion chloride or a nitrate compound; the metal ion chloride is cobalt chloride, and the nitrate compound is one of copper nitrate, zinc nitrate and cobalt nitrate.

[0087] Optionally, the sulfonic acid anion compound is one of sodium ethanedisulfonate and sodium butanedisulfonate;

[0088] Optionally, the organic ligand compound is one of 4,4'-bipyridine, 1,2,4-triazole, and 4,4'-bipyridine disulfide.

[0089] Step S202: vacuum filter the sulfonic acid anion hybrid porous material liquid product at 25° C. to obtain a sulfonic acid anion hybrid porous material solid product.

[0090] Step S203: activating the solid sulfonic acid anion hybrid porous material under vacuum conditions at 100° C. or by purging with an inert gas to remove guest solvent molecules in the pores, thereby obtaining the sulfonic acid anion hybrid porous material.

[0091] The inert gas may be any one or a combination of N2, He, and Ar.

[0092] The process of preparing the sulfonic acid anion hybrid porous material liquid product in step S201 can be achieved by using different methods such as normal temperature stirring method, solvent heating method, solution dropping method, etc. The following are some optional methods:

[0093] Method 1:

[0094] The metal ion inorganic salt, the sulfonic acid anion compound and the organic ligand compound are dissolved in water in a molar ratio of 1:(0.5-3):(1-5), and stirred at room temperature until the reaction is completed to obtain a sulfonic acid anion hybrid porous material liquid product.

[0095] Method 2:

[0096] Dissolve a metal ion inorganic salt and a sulfonic acid anion compound in water or an organic solvent to obtain solution 1, and dissolve an organic ligand compound in water to obtain solution 2, wherein the metal ion inorganic salt, the sulfonic acid anion compound and the organic ligand compound are in a molar ratio of 1:(0.5-3):(1-5); mix solution 1 and solution 2, and stir at room temperature until the reaction is completed to obtain a sulfonic acid anion hybrid porous material liquid product. Wherein, solution 1 is a metal salt-sulfonic acid anion solution, and solution 2 is an organic ligand compound solution.

[0097] Method 3:

[0098] Dissolving the metal ion inorganic salt, the sulfonic acid anion compound and the organic ligand compound in water at a molar ratio of 1:(0.5-3):(1-5), maintaining a specified heating temperature until the reaction is completed, and obtaining a sulfonic acid anion hybrid porous material liquid product;

[0099] Method 4

[0100] Dissolve the metal ion inorganic salt and the sulfonic acid anion compound in water or an organic solvent to obtain solution 1, and dissolve the organic ligand compound in water to obtain solution 2, wherein the metal ion inorganic salt, the sulfonic acid anion compound and the organic ligand compound are in a molar ratio of 1:(0.5-3):(1-5); mix solution 1 and solution 2, maintain a specified heating temperature until the reaction is completed, and obtain a sulfonic acid anion hybrid porous material liquid product. Wherein, solution 1 is a metal salt-sulfonic acid anion solution, and solution 2 is an organic ligand compound solution. When dropping, the organic ligand compound solution is dropped on the metal salt-sulfonic acid anion solution, and the sulfonic acid anion hybrid porous material is prepared by an interfacial diffusion method.

[0101] Method 5

[0102] A metal ion inorganic salt and a sulfonic acid anion compound are dissolved in water or an organic solvent to obtain a solution 1, and an organic ligand compound is dissolved in water to obtain a solution 2, wherein the metal ion inorganic salt, the sulfonic acid anion compound and the organic ligand compound are in a molar ratio of 1:(0.5-3):(1-5); solution 2 is added dropwise to solution 1 and allowed to stand and diffuse until the reaction is completed, thereby obtaining a sulfonic acid anion hybrid porous material liquid product.

[0103] In some optional embodiments, after step S202 and before step S203, the method further includes: washing the sulfonic acid anion hybrid porous material solid product with water or methanol for multiple times and soaking for 8 to 50 hours.

[0104] The embodiment of the present invention also provides an application of a sulfonic acid anion hybrid porous material in an ethylene ethane separation method.

[0105] The present invention prepares several new sulfonic acid anion hybrid porous materials by combining different metal cations, organic ligands and organic anions, and realizes the precise control of the pore size of the sulfonic acid anion hybrid porous materials. Since the pore size of the sulfonic acid anion hybrid porous material is smaller than the kinetic diameter of ethylene and ethane, when ethylene and ethane molecules contact the sulfonic acid anion hybrid porous material, they need to rely on the flexibility of the material and can diffuse into the material pores under the condition that the organic ligand rotates a certain angle. Since ethylene has a smaller molecular size than ethane, it only needs a smaller degree of ligand / anion rotation to enter the pores, and its diffusion process energy barrier is significantly lower than that of ethane. Therefore, the diffusion rate of ethylene in the sulfonic acid anion hybrid porous material is faster than that of ethane, showing good kinetic separation characteristics. At the same time, the pores of the sulfonic acid anion hybrid porous material have high-density oxygen-containing electronegative sulfonic acid action sites, which can form stable hydrogen bond interactions with gas molecules, thereby effectively and selectively capturing ethylene from the mixed gas and realizing efficient thermodynamic separation of ethylene and ethane.

[0106] Compared with the transition metal ion-loaded adsorption material which is the most widely used in the field of ethylene and ethane adsorption separation, the sulfonic acid anion hybrid porous material used in the embodiment of the present invention has a milder interaction with gas molecules, and can achieve efficient separation of ethylene / ethane mixed gas through physical adsorption. The static adsorption isotherm under low pressure is relatively flat, and the material is easier to desorb and regenerate.

[0107] Compared with other porous materials, the sulfonic acid anion hybrid porous material used in the embodiment of the present invention introduces sulfonic acid anions as anion action sites and pillaring ligands, has stronger recognition ability, and better ability to adjust the pore structure and size;

[0108] The sulfonic acid anion hybrid porous material used in the embodiment of the present invention is prepared using raw materials with wide sources and low prices, with mild synthesis conditions, simple methods, good repeatability, good water and thermal stability, and long service life. At the same time, the separation performance is less affected by moisture, sulfide, etc.

[0109] The ethylene-ethane separation method provided in the embodiment of the present invention is a new method for separating ethylene and ethane by adsorption based on sulfonic acid anion hybrid porous material. The sulfonic acid anion hybrid porous material has both suitable pore size and flexibility. When in contact with gas, the pores can deform to allow guest molecules to pass through. Since ethylene has a smaller kinetic size, its diffusion rate in the sulfonic acid anion hybrid porous material is significantly faster than that of ethane, thereby achieving efficient separation of ethylene / ethane mixed gas; and ethylene gas with a purity of more than 96% can be obtained.

[0110] The ethylene-ethane separation method provided in the embodiment of the present invention can realize the efficient separation of ethylene and ethane at normal temperature and pressure. Compared with the low-temperature distillation method widely used in current industrial production, the operating conditions are mild, the energy consumption is significantly reduced, and it is more in line with the concept of sustainable development. At the same time, it has outstanding advantages such as small equipment investment and has good prospects for industrial application.

[0111] The sulfonic acid anion hybrid porous material and its preparation method, and the ethylene ethane separation method using the material provided in the embodiments of the present invention, wherein the prepared sulfonic acid anion hybrid porous material can be purchased from the market, and the relevant experimental data are as follows:

[0112] Example 1

[0113] The above 1 mol of copper nitrate, 1 mol of sodium 1,2'-ethanedisulfonate and 1 mol of 4,4'-bipyridine disulfide were added to 40L of pure water and stirred at room temperature for 12 hours. After the reaction, the solid product was collected by vacuum filtration at 25°C, and the sample was activated under vacuum conditions at 100°C to remove the guest solvent molecules in the pores to obtain the sulfonic acid anion hybrid porous material EDS-SS-Cu, wherein EDS is ethanedisulfonic acid anion, SS is 4,4'-bipyridine disulfide, and Cu is a copper metal node.

[0114] The sulfonic acid anion hybrid porous material EDS-SS-Cu was filled in a 5 cm long fixed bed adsorption column, and ethylene / ethane mixed gas (volume ratio 60:40) was introduced into the bed at a flow rate of 1.0 ml / min at -30°C and 1 bar for fixed bed adsorption. After adsorption for a certain period of time, when the ethylene adsorption front reached about 2 / 3 of the bed, the introduction of the mixed gas was stopped, the adsorption column was depressurized until ethylene just penetrated, and an appropriate amount of high-purity ethylene was introduced for reverse displacement. The ethylene component enriched in the column was desorbed by decompression at 0°C to 0.01 bar to obtain ethylene gas with a purity greater than 97%, and the regeneration of the adsorption column was completed.

[0115] Comparative Example 1

[0116] 5A molecular sieve was filled in a 5 cm long fixed bed adsorption column, and ethylene / ethane mixed gas (volume ratio 60:40) was introduced into the bed at a flow rate of 1.0 ml / min at 25 °C and 2 bar for fixed bed adsorption. After adsorption for a certain period of time, when the ethylene adsorption front reached about 2 / 3 of the bed, the introduction of the mixed gas was stopped, the adsorption column was depressurized until ethylene just penetrated, and an appropriate amount of high-purity ethylene was introduced for reverse displacement. The ethylene component enriched in the column was desorbed by decompression at 25 °C to 0.05 bar to obtain ethylene gas with a purity of 75%.

[0117] Example 2

[0118] 1 mol of copper nitrate, 2 mol of sodium 1,4'-butane disulfonate and 1 mol of 4,4'-bipyridine were added to pure water, placed in a stainless steel reactor with a Teflon liner, and heated to 80 °C for 3 days. After the reaction, the solid product was collected by vacuum filtration at 25 °C and washed with water several times. After that, the guest solvent molecules in the pores were activated and removed under vacuum conditions at 100 °C to obtain the sulfonic acid anion hybrid porous material BDS-1-Cu (BDS: butane disulfonic acid anion; SS: 4,4'-bipyridine; Cu: copper metal node).

[0119] The sulfonic acid anion hybrid porous material BDS-1-Cu product was filled in a 5 cm fixed bed adsorption column, and ethylene / ethane mixed gas (volume ratio 50:50) was introduced into the bed at a flow rate of 0.5 ml / min at 40 °C and 5 bar for fixed bed adsorption. After a certain period of adsorption, the introduction of the mixed gas was stopped after the ethylene component penetrated. The ethylene gas component enriched in the fixed bed was desorbed by heating to 60 °C and reducing the pressure to 1 bar to obtain ethylene gas with a purity of 85%.

[0120] Example 3

[0121] 5 mol 1,2,4-triazole was added to 20 L pure water to form solution 1, and then 1 mol cobalt chloride and 3 mol sodium 1,2'-ethanedisulfonate were added to 20 L pure water to form solution 2 and placed in a test tube. Solution 1 was added dropwise to the test tube and then allowed to stand for reaction. After the reaction was completed, the solid product was collected by vacuum filtration at 25 °C, and then activated and removed the guest solvent molecules in the pores under vacuum conditions at 100 °C to obtain the sulfonic acid anion hybrid porous material EDS-Atz-Co (EDS: ethanedisulfonic acid anion; ATZ: 1,2,4-triazole; Co: cobalt metal node).

[0122] The sulfonic acid anion hybrid porous material EDS-Atz-Co material is made into particles and loaded into a fixed bed adsorption column. At 100°C and 10 bar, ethylene / ethane mixed gas (volume ratio 70:30) is passed into the bed at 5 ml / min for fixed bed adsorption, and fully contacts with the adsorbent particles. After adsorption for a certain period of time and the penetration of the ethylene component, the introduction of the mixed gas is stopped, and the gas enriched in the adsorbent particles is desorbed by heating to 120°C and reducing the pressure to 0.1 bar for desorption. The desorbed gas is then circulated into the fixed bed for adsorption, and desorbed after ethylene adsorption is saturated, and ethylene gas with a purity greater than 95% is obtained by desorption.

[0123] Example 4

[0124] 1 mol zinc nitrate, 2 mol sodium 1,4'-butane disulfonate and 2 mol 4,4'-bipyridine disulfide were added to 40L pure water and stirred at room temperature for reaction. After the reaction was completed, the solid product was collected by vacuum filtration at 25 °C and washed with water several times. The obtained product was activated under vacuum conditions at 100 °C to remove the guest solvent molecules in the pores to obtain the sulfonic acid anion hybrid porous material BDS-SS-Zn (BDS: butane disulfonic acid anion; SS: 4,4'-bipyridine disulfide; Zn: zinc metal node).

[0125] The sulfonic acid anion hybrid porous material BDS-SS-Zn was filled in a 5 cm long fixed bed adsorption column, and an ethylene / ethane mixed gas containing a small amount of methane (volume ratio of ethylene: ethane: methane = 70:30) was introduced at 5 ℃ and 4 bar at a flow rate of 1.0 ml / min for fixed bed adsorption. Ethylene was adsorbed preferentially. When the ethylene adsorption front reached about 2 / 3 of the bed, the introduction of the mixed gas was stopped, the adsorption column was depressurized until ethylene just penetrated, and an appropriate amount of high-purity ethylene was introduced for reverse displacement. The gas in the adsorption column was desorbed by heating to 100 ℃ and then reducing the pressure to 0.5 bar to obtain ethylene gas with a purity of 98%, and the regeneration of the adsorption material was completed.

[0126] Example 5

[0127] 1 mol of cobalt nitrate, 0.5 mol of sodium 1,4'-butane disulfonate and 2 mol of 4,4'-bipyridine disulfide were added to 20L of pure water and stirred at room temperature for reaction. After the reaction was completed, the solid product was collected by vacuum filtration at 25 °C and washed with water several times. The obtained product was activated under vacuum conditions at 100 °C to remove the guest solvent molecules in the pores to obtain the sulfonic acid anion hybrid porous material BDS-SS-Co (BDS: butane disulfonic acid anion; SS: 4,4'-bipyridine disulfide; Co: cobalt metal node).

[0128] The sulfonic acid anion hybrid porous material BDS-SS- Co was filled in two 100 mL fixed bed adsorption columns. At 15°C and 6 bar, a mixture of ethylene / ethane (volume ratio of ethylene: ethane: methane = 80:15:5) containing a small amount of methane was introduced into column 1 at a flow rate of 10.0 mL / min for fixed bed adsorption. Ethylene was preferentially adsorbed. When the ethylene adsorption front reached about 2 / 3 of the bed layer, the introduction of the mixed gas was stopped. After the impurity gas that was not adsorbed in column 1 was discharged, column 1 was evacuated to 0.05 bar with a vacuum pump to obtain the preliminary product gas and complete the regeneration of column 1. The preliminary product gas was introduced into column 2 for adsorption. When the ethylene adsorption front reached about 2 / 3 of the bed layer, the introduction of the mixed gas was stopped. After the impurity gas that was not adsorbed in column 2 was discharged, column 2 was evacuated to 0.05 bar with a vacuum pump to obtain the product gas and complete the regeneration of column 2. Ethylene gas with a purity of 98% was obtained through two adsorption and desorption processes.

[0129] Table 1 below shows the experimental data for the preparation of sulfonic acid anion hybrid porous materials. Table 2 shows the experimental data for the adsorption separation of ethylene and ethane.

[0130] Table 1

[0131]

[0132] It can be seen from Table 1 that the sulfonic acid anion hybrid porous material can be prepared using the sulfonic acid anion hybrid porous material provided by the embodiment of the present invention.

[0133] Table 2

[0134]

[0135] It can be seen from Table 2 that the purity of ethylene obtained by the ethylene-ethane separation method provided in the embodiment of the present invention is higher than 85%, while the purity of ethylene separated by using the 5A molecular sieve is obviously lower than that of the method provided in the embodiment of the present invention.

[0136] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of protection of the present disclosure. The attached method claims present the elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0137] In the above detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than are clearly stated in each claim. On the contrary, as reflected in the appended claims, the invention is in a state of having less than all the features of the disclosed individual embodiments. Therefore, the appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0138] The above description includes examples of one or more embodiments. Of course, it is impossible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it should be recognized by those skilled in the art that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the word is covered in a manner similar to the term "including", just as "including," is explained as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to mean "non-exclusive or".

Claims

1. A method for separating ethylene and ethane, characterized in that: Separation of ethylene and ethane using sulfonic acid anion hybrid porous materials; The sulfonic acid anion hybrid porous material is composed of sulfonic acid anions S, organic ligands L and metal cations M through coordination bonds, and its chemical formula is: , where n is a positive integer, indicating that the material is composed of a number of The structural units are expanded in space; The sulfonate anion is an ethanedisulfonate anion or a butanedisulfonate anion; The metal cation is Cu 2+ 、Zn 2+ 、Co 2+ One of; The organic ligand is 1,2,4-triazole; the organic ligand is coordinated with the metal cation through the nitrogen atom, and the organic ligand is di-coordinated; the sulfonate anion is coordinated with the metal cation through the oxygen atom, and each sulfonate anion is connected to two different metal cations; each metal cation is connected to four organic ligands and coordinated with two oxygen atoms.

2. A separation method according to claim 1, characterized in that: The preparation process of the sulfonic acid anion hybrid porous material comprises: Using metal ion inorganic salt, sulfonic acid anion compound and organic ligand compound in a molar ratio of 1: (0.5-3): (1-5) to prepare a sulfonic acid anion hybrid porous material liquid product; Vacuum-filtering the sulfonic acid anion hybrid porous material liquid product at 25° C. to obtain a sulfonic acid anion hybrid porous material solid product; The solid product of the sulfonic acid anion hybrid porous material is activated under vacuum conditions at 100° C. or by purging with an inert gas, and the guest solvent molecules in the pores are removed to obtain the sulfonic acid anion hybrid porous material.

3. The separation method according to claim 2, characterized in that The method uses a metal ion inorganic salt, a sulfonic acid anion compound and an organic ligand compound in a molar ratio of 1:(0.5-3):(1-5) to prepare a sulfonic acid anion hybrid porous material liquid product, including: Dissolving a metal ion inorganic salt, a sulfonic acid anion compound and an organic ligand compound in water at a molar ratio of 1:(0.5-3):(1-5), stirring at room temperature until the reaction is completed or maintaining a specified heating temperature until the reaction is completed, to obtain a sulfonic acid anion hybrid porous material liquid product; or; A metal ion inorganic salt and a sulfonic acid anion compound are dissolved in water to obtain a solution 1, and an organic ligand compound is dissolved in water or an organic solvent to obtain a solution 2, wherein the metal ion inorganic salt, the sulfonic acid anion compound and the organic ligand compound are in a molar ratio of 1:(0.5-3):(1-5), and the solution 2 is added dropwise to the solution 1 and allowed to stand and diffuse until the reaction is completed, or the solution 1 and the solution 2 are mixed and stirred at room temperature until the reaction is completed or maintained at a specified heating temperature until the reaction is completed, to obtain a sulfonic acid anion hybrid porous material liquid product.

4. The separation method according to claim 3, characterized in that The stirring at room temperature until the reaction is completed includes: stirring at room temperature for no less than 12 hours.

5. The separation method according to claim 3, characterized in that The maintaining the designated heating temperature until the reaction is completed includes: heating to 80° C. and maintaining it for 3 days.

6. The separation method according to claim 2, characterized in that After obtaining the sulfonic acid anion hybrid porous material solid product and before activating it, the method further comprises: washing with water or methanol for multiple times and soaking for 8 to 50 hours.

7. The separation method according to any one of claims 2 to 6, characterized in that: The metal ion inorganic salt is a metal ion chloride or nitric acid compound; The sulfonic acid anion compound is one of sodium ethanedisulfonate and sodium butyldisulfonate.

8. The separation method according to claim 7, characterized in that The metal ion chloride is cobalt chloride, and the nitric acid compound is one of copper nitrate, zinc nitrate and cobalt nitrate.

9. The separation method according to claim 1, characterized in that The separation method comprises: A mixed gas containing ethylene and ethane is brought into contact with the sulfonic acid anion hybrid porous material, and the sulfonic acid anion hybrid porous material adsorbs the ethylene to separate the ethane.

10. The separation method according to claim 9, characterized in that Also includes: The sulfonic acid anion hybrid porous material adsorbing ethylene is subjected to a desorption treatment to obtain ethylene.

11. The separation method according to claim 9, characterized in that The step of bringing the mixed gas containing ethylene and ethane into contact with the sulfonic acid anion hybrid porous material comprises: The mixed gas containing ethylene and ethane is brought into contact with the sulfonic acid anion hybrid porous material through at least one of fixed bed adsorption and moving bed adsorption.

12. The separation method according to claim 11, characterized in that The mixed gas containing ethylene and ethane is brought into contact with the sulfonic acid anion hybrid porous material by fixed bed adsorption to separate ethane, including: A mixed gas containing ethylene and ethane enters a fixed bed at a set flow rate under a set adsorption temperature and pressure, and contacts with a sulfonic acid anion hybrid porous material in a fixed bed adsorption column to adsorb ethylene, and obtains a gas containing ethane at the outlet of the adsorption column; When ethylene appears at the outlet of the adsorption column, or the concentration gradient front of ethylene in the bed is not lower than the set proportion of the bed, stop the mixed gas input.

13. The separation method according to claim 10, characterized in that The sulfonic acid anion hybrid porous material adsorbing ethylene is subjected to a desorption treatment to obtain ethylene, comprising: At a set desorption temperature and desorption pressure, the ethylene adsorbed by the sulfonic acid anion hybrid porous material in the fixed bed adsorption column is desorbed to obtain ethylene at the outlet of the adsorption column; or At the set desorption temperature and desorption pressure, the ethylene adsorbed by the sulfonic acid anion hybrid porous material in the fixed bed adsorption column is desorbed, and pure ethylene is introduced for reverse replacement to obtain ethylene at the outlet of the adsorption column.

14. The separation method according to claim 13, characterized in that The adsorption temperature is 25-40° C., the adsorption pressure is 1-5 bar, the desorption temperature is 60-100° C., and the desorption pressure is 0.01-0.1 bar.

15. The separation method according to claim 12, characterized in that The set flow rate is 0.5~10.0mL / min.

16. The separation method according to any one of claims 9 to 15, characterized in that: The mixed gas contains 10% to 90% ethylene, 10% to 90% ethane, and 0% to 20% impurity gas.

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