Mononuclear Ag (I) complex crystal, preparation method, load, device and application
By using mononuclear Ag(I) complex crystals as adsorbents, the problem of high energy consumption in the separation of ethylene and ethane was solved, achieving efficient and low-cost ethylene/ethane separation. The material exhibits good selectivity and stability.
Patent Information
- Application Number
- CN202511969448.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-24
- Publication Date
- 2026-04-07
AI Technical Summary
Existing technologies for separating ethylene and ethane are energy-intensive, time-consuming, and require large equipment investments. Traditional separation methods are difficult to efficiently separate ethylene and ethane mixtures.
Using mononuclear Ag(I) complex crystals as adsorbents, and employing the π-complex adsorption separation method, Ag(I) forms a composite material with a suitable support to achieve efficient separation of ethylene and ethane.
A highly selective and stable ethylene adsorbent material was obtained, which can efficiently separate ethylene/ethane mixed gases. The production process is simple, has a high yield, and is well controllable.
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Figure CN121800830A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of gas phase separation technology, specifically relating to a mononuclear Ag(I) complex crystal, its preparation method, loading material, apparatus, and application. Background Technology
[0002] Ethylene (C2H4) is one of the world's largest chemical products, widely used in the manufacture of polymers such as polyethylene, polyvinyl chloride, and polystyrene, as well as other organic chemicals. Steam cracking and ethane dehydrogenation are the main methods for producing ethylene, and these processes inevitably introduce ethane (C2H6) impurities. Therefore, the separation and purification of ethylene is of great significance in the petrochemical industry. However, due to the extremely similar physicochemical properties of ethylene and ethane, separation is quite difficult. Traditional gas separation methods such as cryogenic distillation and solvent absorption often suffer from drawbacks such as high energy consumption, long processing times, and large equipment investments. To reduce the energy consumption required for separation and lower costs, there is an urgent need to develop more efficient, energy-saving, and environmentally friendly separation technologies. Adsorption separation technology has advantages such as low energy consumption, simple operation, and relatively low cost, and is gradually replacing traditional distillation separation technology. The core of adsorption separation technology lies in the selection of the adsorbent.
[0003] π-complex adsorption separation, as a novel adsorption separation technology between physical adsorption and chemisorption, has promising prospects for industrial applications. Research in this field has long focused on loading Ag(I) and Cu(I) onto suitable supports to form composite materials for the separation of ethylene and ethane.
[0004] Therefore, in order to address the above-mentioned technical problems, it is necessary to provide a mononuclear Ag(I) complex crystal, its preparation method, its loading material, its apparatus, and its application. Summary of the Invention
[0005] The purpose of this invention is to provide a mononuclear Ag(I) complex crystal, its preparation method, its loading material, its apparatus, and its application. This invention yields a high-performance, highly selective ethylene adsorption crystal material with excellent stability and selective ethylene adsorption, capable of efficiently separating ethylene / ethane mixed gases. The production process of this material is simple, with high yield and good controllability.
[0006] To achieve the above objectives, a specific embodiment of the present invention provides the following technical solution:
[0007] The mononuclear Ag(I) complex crystal has the molecular formula [Ag(PPh3)2(CH3CN)][BF4]·0.5CH2Cl2, and is a monoclinic crystal system, wherein PPh3 is triphenylphosphine and Ag is monovalent silver. Preferably, the mononuclear Ag(I) complex crystal of the present invention has the chemical formula C 38.5 H 34AgBClF4NP2.
[0008] In one or more embodiments of the present invention, the crystal has a space group of C2 / c and satisfies the following cell parameters: a = 23.115(2) Å, b = 12.7753(13) Å, c = 25.276(3) Å, α = 90.00 o ,β=97.2420(10)°, =90.00 o .
[0009] In one or more embodiments of the present invention, the monovalent silver is derived from a soluble Ag salt. Preferably, the soluble Ag salt is selected from silver nitrate or silver acetate.
[0010] In one or more embodiments of the present invention, a method for preparing mononuclear Ag(I) complex crystals includes: under a protective atmosphere, a pre-reacted soluble Ag salt and a ligand undergo a coordination reaction in a first solvent, the first solvent is removed to obtain a solid, the solid is then dissolved in dichloromethane solvent, a poor solvent is added to perform two-phase diffusion, and the target crystal is obtained by separation.
[0011] In one or more embodiments of the present invention, the protective gas atmosphere is selected from: nitrogen atmosphere, argon atmosphere, helium atmosphere, and neon atmosphere.
[0012] In one or more embodiments of the present invention, the first solvent is selected from acetonitrile.
[0013] In one or more embodiments of the present invention, the unsuitable solvent is selected from solvents with low polarity, a density not greater than that of dichloromethane, and miscibility with dichloromethane. Preferably, n-hexane.
[0014] In one or more embodiments of the present invention, the pre-reaction is a reaction between a soluble Ag salt and a tetrafluoroborate in a first solvent. Preferably, the tetrafluoroborate is selected from sodium tetrafluoroborate, potassium tetrafluoroborate, and other salts that can be dispersed in the reaction system.
[0015] In one or more embodiments of the present invention, the amount of soluble Ag salt used satisfies the following condition: each 1 mmol of soluble Ag salt corresponds to the use of 20-40 mL of the first solvent.
[0016] In one or more embodiments of the present invention, the molar ratio of soluble Ag salt to ligand, calculated as Ag, is 1:(1-2).
[0017] In one or more embodiments of the present invention, the molar ratio of soluble Ag salt to tetrafluoroborate, calculated as Ag, is 1:(1-2). Preferably, the molar ratio of AgNO3 to NaBF4 is 1:(1-2), meaning that 1 mmol of AgNO3 corresponds to 1-2 mmol of NaBF4 in the reaction step.
[0018] In one or more embodiments of the present invention, each 1 mmol of soluble Ag salt corresponds to 5-10 mL of dichloromethane in the steps.
[0019] In one or more embodiments of the present invention, each 1 mmol of soluble Ag salt corresponds to 15-30 mL of n-hexane in the steps.
[0020] In one or more embodiments of the present invention, the loading includes a carrier and a mononuclear Ag(I) complex crystal loaded onto the carrier.
[0021] In one or more embodiments of the present invention, the apparatus includes a body for providing a load cavity containing a crystal or load.
[0022] In one or more embodiments of the present invention, the application of mononuclear Ag(I) complex crystals or supports or devices in the separation of ethylene / ethane.
[0023] Compared with the prior art, the mononuclear Ag(I) complex crystal material, preparation method, loading material, apparatus and application of the present invention have efficiently obtained a high-quality crystal material with good stability and selective ethylene adsorption, which can efficiently separate ethylene / ethane mixed gas. The production and preparation process of this material is simple, with high yield and good controllability. Attached Figure Description
[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0025] Figure 1 The diagram shows the coordination structure of [Ag(PPh3)2(CH3CN)][BF4]·0.5CH2Cl2 according to one embodiment of the present invention, where P1 and P2 refer to phosphorus atoms, N1 refers to nitrogen atoms, and Ag1 refers to the central silver (I) ion.
[0026] Figure 2 This is a thermogravimetric curve of [Ag(PPh3)2(CH3CN)][BF4]·0.5CH2Cl2 according to one embodiment of the present invention;
[0027] Figure 3 This is a single-component ethylene adsorption curve of [Ag(PPh3)2(CH3CN)][BF4]·0.5CH2Cl2 according to one embodiment of the present invention;
[0028] Figure 4 This is a single-component adsorption curve of ethane [Ag(PPh3)2(CH3CN)][BF4]·0.5CH2Cl2 according to one embodiment of the present invention. Detailed Implementation
[0029] To enable those skilled in the art to better understand the technical solutions in this disclosure, the technical solutions of this invention will be clearly and completely described below in conjunction with the embodiments disclosed herein. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this disclosure.
[0030] Before being used for adsorption, the crystals shown in the examples below can be pretreated. The principle of pretreatment is to further remove the coordinated acetonitrile molecules by heating under reduced pressure, thereby freeing up more adsorption sites to achieve a higher adsorption effect.
[0031] In the examples shown below, including but not limited to those described below, the reactions were carried out under a protective atmosphere such as nitrogen or argon. In the examples shown below, the reactions were carried out under a nitrogen atmosphere. If the sample required pretreatment, the acetonitrile molecules were completely removed under vacuum and 100°C to obtain the [Ag(PPh3)2][BF4] material (state 1) for testing. State 1 refers to the chemical formula [Ag(PPh3)2][BF4] formed after the coordinated acetonitrile was removed under vacuum and 100°C.
[0032] Example 1
[0033] The preparation process of the crystal material in this embodiment is as follows:
[0034] Under a nitrogen atmosphere, silver nitrate (1 mmol) and NaBF4 (1 mmol) were dissolved in acetonitrile (30 mL), heated to 85 °C, and stirred under reflux for 1 h. Then, the organic ligand triphenylphosphine (2 mmol) was added, and the mixture was stirred under reflux for another 2 h. After rotary evaporation, the solid was dissolved in 5 mL of dichloromethane, and 15 mL of n-hexane was added dropwise to the upper layer for diffusion. The mixture was sealed and left to stand for 3 days, and colorless crystals precipitated.
[0035] The yield of the mononuclear Ag(I) complex crystal material prepared in this embodiment was 67.2%.
[0036] The characterization of the binuclear Ag(I) complex crystal material prepared in this embodiment is as follows:
[0037] (1) Determination of crystal structure
[0038] A single crystal of appropriate size was selected under a microscope, and its structure was measured at room temperature using a graphite-monochromatic molybdenum target (MoKα, λ = 0.71073 Å) on a Bruker SMART Apex II ICCD single crystallometer. Data were collected and the unit cell determined using the APEXII program. Structural data were normalized and absorption corrected using the SAINT and SADABS programs. The structure was analyzed using the SHENXTL-97 program. The coordinates of all non-hydrogen atoms were obtained by difference Fourier synthesis, and the atomic coordinates and anisotropic temperature factor were corrected using the full matrix least squares method. All hydrogen atoms were theoretically hydrogenated. Crystallographic data are shown in Table 1, and the structure diagram is shown in [Table 1]. Figure 1 The coordinate bond lengths and bond angles are shown in Table 2.
[0039] Table 1 Crystallographic data of the coordination compounds
[0040]
[0041] Table 2 Coordination bond lengths and bond angles of coordination compounds
[0042]
[0043] Figure 1 The structural diagram shows that Ag(I) coordinates with two phosphorus atoms on triphenylphosphine and one nitrogen atom on acetonitrile, forming a three-coordinate planar triangular configuration. The relevant bond lengths and bond angles are shown in Table 2, all within the normal range.
[0044] (2) Thermogravimetric analysis
[0045] The obtained complex crystals were subjected to thermogravimetric analysis (TGA) using a Pyris Diamond TG-DTA instrument. The thermal stability of the complex was determined by the weight loss and thermal changes of the crystals. The stability of this crystalline material was investigated using TGA. Figure 2 The results show significant weight loss around 100℃, attributed to the loss of acetonitrile and CH2Cl2 from the complex [Ag(PPh3)2(CH3CN)][BF4]·0.5CH2Cl2. Further weight loss begins at 250℃, indicating decomposition of the main structure of the complex. Therefore, this crystalline material exhibits high stability.
[0046] (3) Adsorption performance test
[0047] In this embodiment, the crystal material, after being pretreated under vacuum and at 100°C, is used in State 1 for performance testing of selective separation of ethylene / ethane mixed gas.
[0048] The adsorption performance of the obtained complex crystal material on ethylene and ethane was studied using an IGA-100 gravimetric adsorption analyzer. Figure 3The single-component adsorption curves of ethylene in the study show that [Ag(PPh3)2][BF4] has a good adsorption capacity for ethylene gas. However, Figure 4 The [Ag(PPh3)2][BF4] exhibits almost no adsorption capacity for ethane. Therefore, the crystalline material of the present invention has a high selective adsorption capacity for ethylene, thereby enabling the separation of ethylene / ethane mixtures.
[0049] Example 2
[0050] The preparation process of the crystal material in this embodiment is as follows:
[0051] Under a nitrogen atmosphere, silver acetate (1 mmol) and NaBF4 (1 mmol) were dissolved in acetonitrile (30 mL), heated to 85 °C, and stirred under reflux for 1 h. Then, the organic ligand triphenylphosphine (2 mmol) was added, and the mixture was stirred under reflux for another 2 h. After rotary evaporation, the solid was dissolved in 5 mL of dichloromethane, and 15 mL of n-hexane was added dropwise to the upper layer for diffusion. The mixture was sealed and left to stand for 3 days, and colorless crystals precipitated.
[0052] The yield of the mononuclear Ag(I) complex crystal material prepared in this embodiment was 63.9%, and the crystal structure of the product was found to be consistent with... Figure 1 The crystal structure is consistent with that shown in Table 1, and the purity and thermal stability of the sample in this example meet the application requirements. Furthermore, the sample in this example, after undergoing the same pretreatment as above in state 1, exhibits high selective adsorption capacity for ethylene, while showing almost no adsorption for ethane, essentially matching the... Figure 3-4 The consistency shown.
[0053] Example 3
[0054] The preparation process of the crystal material in this embodiment is as follows:
[0055] Under a nitrogen atmosphere, silver nitrate (1 mmol) and KBF4 (1 mmol) were dissolved in acetonitrile (30 mL), heated to 85 °C, and stirred under reflux for 1 h. Then, the organic ligand triphenylphosphine (2 mmol) was added, and the mixture was stirred under reflux for another 2 h. After rotary evaporation, the solid was dissolved in 5 mL of dichloromethane, and 15 mL of n-hexane was added dropwise to the upper layer for diffusion. The mixture was sealed and left to stand for 3 days, and colorless crystals precipitated.
[0056] The yield of the mononuclear Ag(I) complex crystal material prepared in this embodiment was 64.2%, and the crystal structure of the product was found to be consistent with... Figure 1 The crystal structure is consistent with that shown in Table 1, and the purity and thermal stability of the sample in this example meet the application requirements. Furthermore, the sample in this example, after undergoing the same pretreatment as above in state 1, exhibits high selective adsorption capacity for ethylene, while showing almost no adsorption for ethane, essentially matching the... Figure 3-4 The consistency shown.
[0057] Including but not limited to the crystal materials obtained in the above embodiments, all satisfy the following conditions. Figure 1 The configuration shown indicates that Ag(I) coordinates with the phosphorus atoms on the two triphenylphosphine atoms and the nitrogen atom on the acetonitrile, forming a tricoordinate planar triangular configuration. Furthermore, like the sample obtained in Example 1, the samples obtained in each example exhibit good thermal stability and high selective adsorption capacity for ethylene, thus enabling the separation of ethylene / ethane mixtures.
[0058] It will be apparent to those skilled in the art that this disclosure is not limited to the details of the exemplary embodiments described above, and that this disclosure can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of this disclosure is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this disclosure. No reference numerals in the claims should be construed as limiting the scope of the claims.
[0059] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.
Claims
1. A mononuclear Ag(I) complex crystal with the molecular formula [Ag(PPh3)2(CH3CN)][BF4]·0.5CH2Cl2, belonging to the monoclinic crystal system, wherein: PPh3 is triphenylphosphine, and Ag is monovalent silver.
2. The mononuclear Ag(I) complex crystal according to claim 1, characterized in that, The crystal has space group C2 / c and satisfies the following cell parameters: a = 23.115(2) Å, b = 12.7753(13) Å, c = 25.276(3) Å, α = 90.00 o ,β=97.2420(10)°, =90.00 o .
3. The mononuclear Ag(I) complex crystal according to claim 1, characterized in that, The monovalent silver is derived from soluble Ag salts.
4. A method for preparing mononuclear Ag(I) complex crystals according to any one of claims 1-3, comprising: Under a protective atmosphere, the pre-reacted soluble Ag salt and ligand undergo a coordination reaction in the first solvent. After removing the first solvent, a solid is obtained. The solid is then dissolved in dichloromethane solvent, and a poor solvent is added to carry out two-phase diffusion. The target crystal is then obtained by separation.
5. The method for preparing mononuclear Ag(I) complex crystals according to claim 4, characterized in that, The first solvent is selected from acetonitrile.
6. The method for preparing mononuclear Ag(I) complex crystals according to claim 4, characterized in that, The unsuitable solvent is selected from solvents with low polarity, a density not greater than that of dichloromethane, and miscibility with dichloromethane.
7. The method for preparing mononuclear Ag(I) complex crystals according to claim 4, characterized in that, The pre-reaction involves the reaction of a soluble Ag salt with a tetrafluoroborate in a first solvent.
8. A loading material, including a carrier and a mononuclear Ag(I) complex crystal as described in any one of claims 1-3 loaded onto the carrier.
9. An apparatus comprising a body for providing a load cavity, the load cavity containing a crystal as claimed in any one of claims 1-3 or a load as claimed in claim 8.
10. The use of the mononuclear Ag(I) complex crystal as described in any one of claims 1-3, or the supported material as described in claim 8, or the apparatus as described in claim 9, in the separation of ethylene / ethane.