Preparation method of indium-based metal organic framework material and application in separating ethane and ethylene
By preparing an indium-based metal-organic framework material with the chemical formula C39H39BN8O17In3, the problems of insufficient adsorption capacity and selectivity in ethylene-ethane separation in the existing technology were solved, and efficient and low-cost ethylene purification effects were achieved.
Patent Information
- Application Number
- CN202510048626.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-13
- Publication Date
- 2025-10-17
- Estimated Expiration
- 2045-01-13
AI Technical Summary
Existing MOFs materials have limited adsorption capacity and insufficient selectivity in ethylene and ethane separation, resulting in high energy consumption and high investment.
An indium-based metal-organic framework material with the chemical formula C39H39BN8O17In3 was prepared by solvent thermal reaction, combined with sodium tri(1H-imidazole-1-yl)borohydride and terephthalic acid as ligands to form an In-BH(im)3-BDC material with a three-dimensional framework structure for the selective separation of ethane and ethylene.
It achieves separation of ethane and ethylene with high selectivity and high adsorption capacity, reduces energy consumption and investment, and is suitable for industrial applications.
Smart Images
Figure CN119823411B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of gas adsorption separation, and particularly relates to an indium-based metal organic framework material, a preparation method thereof and application thereof in separating ethane and ethylene. BACKGROUND
[0002] Ethylene, as an important industrial raw material, is widely used in the fields of chemical industry, petrochemical industry and polymer, etc., and its production capacity marks the development level of a country's petrochemical industry. The main production processes of ethylene include steam cracking of naphtha and steam cracking of ethane. However, in the steam cracking process, ethane byproduct with high similarity in physical properties and molecular size to ethylene is inevitably mixed, which has a great negative impact on the polymerization and downstream processing of ethylene in the later stage. At present, the method for separating ethane and ethylene in industry has defects such as high energy consumption and high investment, and therefore it is urgent to develop a green, energy-saving and economical method for replacement.
[0003] The adsorption separation technology of porous materials has potential advantages of low energy consumption and low investment, and compared with other porous materials, metal organic framework materials (MOFs) are widely concerned in the field of gas separation due to their unique structural designability and easily adjustable pore function. In the field of ethylene and ethane separation, ethane selective MOFs can reduce the energy consumption of desorption and realize one-step purification of ethylene. However, the reported MOF materials currently have problems such as limited adsorption capacity and insufficient selectivity. SUMMARY
[0004] The purpose of the present application is to provide an indium-based metal organic framework material, a preparation method thereof and application thereof in separating ethane and ethylene. The indium-based metal organic framework material provided by the present application can selectively separate ethane and ethylene and has high adsorption capacity.
[0005] In order to achieve the above purpose, the present application provides the following technical scheme:
[0006] The present application provides an indium-based metal organic framework material, which has a chemical formula of C 39 H 39 BN8O 17 In3, a molecular formula of [In3O(BH(im)3)(BDC)3](DMF)2(H2O); the coordination metal of the indium-based metal organic framework material is In 3+ , and the organic ligand is tris(1H-imidazol-1-yl) sodium borohydride and terephthalic acid.
[0007] Preferably, the molar ratio of the tris(1H-imidazol-1-yl) sodium borohydride and the terephthalic acid is 1-3:1.
[0008] Preferably, the specific surface area of the indium-based metal organic framework material is 700-1200 m2 / g, pore volume is 0.2~0.5cm 2 / g, and the porosity is 70-95%.
[0009] The present invention also provides a method for preparing the indium-based metal-organic framework material described in the above scheme, comprising the following steps:
[0010] An indium salt, an organic ligand and a solvent are mixed to carry out a solvothermal reaction, wherein the organic ligand comprises sodium tris(1H-imidazol-1-yl)borohydride and terephthalic acid, so as to obtain an indium-based metal organic framework material.
[0011] Preferably, the molar ratio of the indium salt to sodium tri(1H-imidazol-1-yl)borohydride is 1:1-5; the molar ratio of the indium salt to terephthalic acid is 1-3:1; the volume ratio of the amide solvent to the low-boiling point solvent is 1-4:1; and the ratio of the amount of the indium salt to the volume of the solvent is (0.01-0.1) mmol:(1-4) mL.
[0012] Preferably, the temperature of the solvent thermal reaction is 80-160° C., and the insulation reaction time is 8-24 hours; and the solvent thermal reaction is carried out under closed conditions.
[0013] The present invention also provides the use of the indium-based metal-organic framework material described in the above scheme or the indium-based metal-organic framework material obtained by the preparation method described in the above scheme in the field of separation and purification of ethylene.
[0014] Preferably, the indium-based metal-organic framework material is activated before use; the activation comprises the following steps: degassing and activating the indium-based metal-organic framework material after solvent exchange.
[0015] Preferably, the solvent for solvent exchange is dichloromethane; the frequency of solvent exchange is once every 1 to 3 hours, and the total exchange time is 3 to 5 days.
[0016] Preferably, the temperature of the degassing activation is 80-150° C., and the activation time is 8-12 hours; and the degassing activation is carried out in dry conditions.
[0017] The application provides an indium-based metal organic framework material. The indium-based metal organic framework material (named In-BH(im)3-BDC) provided by the application has a molecular formula of [In3O(BH(im)3)(BDC)3](DMF)2(H2O), good stability and high separation selectivity of ethane and ethylene. The indium-based metal organic framework material provided by the application has a classic pacs-MOFs structure, the structure platform is composed of a 9-connected three-nuclear indium cluster [In3O(COO)6], six linear dicarboxylic acid ligands and three tri-imidazole ligands (3,9)-connected three-dimensional framework structure. The application cuts the metal organic framework main framework into a triangular bipyramidal cage and a cylindrical cage by introducing sodium tri(1H-imidazole-1-yl)borohydride, so that the indium-based metal organic framework material has good selectivity in separating ethane and ethylene. In addition, the indium-based metal organic framework material provided by the application has high crystallinity, large specific surface area and high ethane adsorption capacity, and can effectively separate and purify ethylene in one step.
[0018] The application further provides a preparation method of the indium-based metal organic framework material. 3+ The preparation method provided by the application uses In as a coordination metal, sodium tri(1H-imidazole-1-yl)borohydride and terephthalic acid as organic ligands, and prepares the indium-based metal organic framework material through a solvothermal reaction in an organic solvent, so that the preparation method is simple and low in cost.
[0019] The application further provides application of the indium-based metal organic framework material in the field of separating and purifying ethylene. The indium-based metal organic framework material provided by the application is suitable for selectively separating and purifying ethylene, especially separating ethane and ethylene mixed gas, has low adsorbent dosage and cost, has a simple separation process, and has a wide application prospect. BRIEF DESCRIPTION OF DRAWINGS
[0020] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings described below are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of these drawings.
[0021] Figure 1 It is an electron microscope photo of the indium-based metal organic framework material of Example 1.
[0022] Figure 2 It is a structure diagram of the indium-based metal organic framework material of Example 1.
[0023] Figure 3 It is an X-ray diffraction spectrum and a structure simulation PXRD spectrum of the indium-based metal organic framework material of Example 1.
[0024] Figure 4 77K nitrogen adsorption curve of the indium-based metal-organic framework material of the present invention;
[0025] Figure 5 The single-component adsorption isotherm curve of ethane / ethylene of the indium-based metal-organic framework material of the present invention;
[0026] Figure 6 This is the IAST separation coefficient curve of the indium-based metal organic framework material of the present invention for ethane / ethylene at 298K. DETAILED DESCRIPTION
[0027] The present invention provides an indium-based metal organic framework material, the chemical formula of which is C 39 H 39 BN8O 17 In3, the molecular formula is [In3O(BH(im)3)(BDC)3](DMF)2(H2O); the coordination metal of the indium-based metal organic framework material is In 3+ , the organic ligands are sodium tri(1H-imidazol-1-yl)borohydride and terephthalic acid.
[0028] In the present invention, the molar ratio of sodium tris(1H-imidazol-1-yl)borohydride to terephthalic acid is preferably 1 to 3:1, specifically 1:1, 1.5:1, 2:1, 2.5:1 or 3:1.
[0029] In the present invention, the specific surface area of the indium-based metal organic framework material is preferably 700 to 1200 m 2 / g, specifically 910m 2 / g, and the pore volume is preferably 0.2 to 0.5 cm 2 / g, specifically 0.35cm 2 / g, and the porosity is preferably 70 to 95%, and specifically 90%.
[0030] The indium-based metal-organic framework material provided by the present invention has a trinuclear indium cluster structural unit (trinuclear indium cluster [In3O(COO)6]), and each trinuclear indium cluster [In3O(COO)6] forms a (3,9)-connected three-dimensional framework structure with 6 linear dicarboxylic acid ligands and 3 triimidazole ligands.
[0031] The present invention also provides a method for preparing the indium-based metal-organic framework material described in the above scheme, comprising the following steps:
[0032] An indium salt, an organic ligand, nitric acid and a solvent are mixed (referred to as the first mixture) for a solvothermal reaction, wherein the organic ligand includes sodium tris(1H-imidazol-1-yl)borohydride and terephthalic acid to obtain an indium-based metal organic framework material.
[0033] In the present application, the indium salt is preferably a soluble indium salt; the soluble indium salt preferably comprises one or more of indium chloride, indium bromide, indium acetate and indium nitrate; the indium nitrate is preferably hydrated indium nitrate; the hydrated indium nitrate is preferably indium nitrate tetrahydrate.
[0034] In the present application, the molar ratio of the indium salt to sodium tris(1H-imidazol-1-yl)borohydride is preferably 1:1-5, and can be 1:3 or 1:4 in particular; the molar ratio of the indium salt to terephthalic acid is preferably 1-3:1, and can be 2:1 in particular.
[0035] In the present application, the ratio of the amount of substance of the indium salt to the volume of nitric acid is preferably (0.01-0.1) mmol:(0.03-0.3) mL, and can be 0.05 mmol:0.1 mL in particular. By adding nitric acid, the present application adjusts the pH value of the reaction system on the one hand, ensuring the optimal conditions for the synthesis of metal organic framework materials, and an appropriate pH value helps to form a uniform and stable metal organic framework structure; on the other hand, it changes the solvent polarity, thereby affecting the synthesis process of the metal organic framework material. By adjusting the solvent polarity, the crystal growth and morphology of the metal organic framework can be controlled.
[0036] In the present application, the solvent preferably comprises an amide solvent and a low-boiling-point solvent; the amide solvent preferably comprises one or more of N,N-dimethylformamide, N,N-dimethylacetamide and N,N-diethylformamide, and is more preferably N,N-dimethylformamide; the low-boiling-point solvent preferably comprises one or more of water, acetonitrile, methanol and ethanol, and is more preferably acetonitrile; the volume ratio of the amide solvent to the low-boiling-point solvent is preferably 1-4:1, and can be 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1 or 4:1 in particular.
[0037] In the present application, the ratio of the amount of substance of the indium salt to the volume of the solvent is preferably (0.01-0.1) mmol:(1-4) mL, and can be 0.05 mmol:1 mL in particular.
[0038] In the present application, the first mixing is preferably mixing of the indium salt, the organic ligand and the amide solvent (denoted as mixing A) to obtain a mixed solution, and mixing of the mixed solution and the low-boiling-point solvent with nitric acid.
[0039] In the present application, the mixing A is preferably ultrasonic mixing.
[0040] In the present application, the temperature of the solvothermal reaction is preferably 80-160℃, and can be 110℃ or 120℃ in particular; the holding reaction time is preferably 8-24h, and can be 12h, 14h or 16h in particular; and the solvothermal reaction is preferably carried out in a closed condition.
[0041] In the present application, the solvothermal reaction is preferably followed by washing and drying the obtained reaction product; the washing reagent is preferably N,N-dimethylformamide.
[0042] The present application also provides the application of the indium-based metal organic framework material prepared by the above preparation method in the field of separation and purification of ethylene.
[0043] The indium-based metal organic framework material provided by the present application is used for separation and purification of ethylene, especially separation of ethane / ethylene mixed gas; the volume ratio of ethane to ethylene in the ethane / ethylene mixed gas is preferably 0.5:0.5 or 0.9:0.1.
[0044] In the present application, the indium-based metal organic framework material is preferably activated before use; the activation preferably comprises the following steps: degassing activation after solvent exchange of the indium-based metal organic framework material.
[0045] In the present application, the solvent used for solvent exchange is preferably dichloromethane; the frequency of solvent exchange is preferably 1 time per 1-3h, and can be 1 time per 2h in particular; and the total exchange time is preferably 3-5 days, and can be 4 days in particular.
[0046] In the present application, the temperature of degassing activation is preferably 80-150℃, and can be 80℃, 100℃, 120℃, 135℃ or 150℃ in particular; and the activation time is preferably 8-12h, and can be 10h in particular; and the degassing activation is preferably carried out in a dry condition. Through activation, the present application removes free solvent molecules in the pores of the material.
[0047] In order to further illustrate the present application, the schemes of the present application are described in detail below in combination with the drawings and examples, but they should not be understood as limiting the scope of protection of the present application.
[0048] Example 1
[0049] Under room temperature, 15 mg of indium nitrate tetrahydrate and 9 mg of terephthalic acid were dissolved in 0.5 mL of N,N-dimethylformamide, 30 mg of tris(1H-imidazol-1-yl) sodium borohydride was dissolved in 0.5 mL of N,N-dimethylformamide, then the two were mixed and added into 0.5 mL of acetonitrile and 0.1 mL of nitric acid, after ultrasonic mixing for 40 s, the obtained mixture was transferred into a 10 mL glass vial, which was capped and stored in a 120℃ oven, and the solvent thermal reaction was carried out under the pressure generated by the glass vial for 12 h, after taking out and cooling, the product was collected, washed with DMF and dried, to obtain an indium-based metal organic framework material, which was a colorless hexagonal prism crystal.
[0050] Example 2
[0051] Under room temperature, 10 mg of indium nitrate tetrahydrate, 7 mg of terephthalic acid and 20 mg of tris(1H-imidazol-1-yl) sodium borohydride were dissolved in 1 mL of N,N-dimethylformamide, then 0.8 mL of acetonitrile and 0.2 mL of nitric acid were added into the obtained mixture, after ultrasonic mixing for 40 s, the obtained mixture was transferred into a 10 mL glass vial, which was capped and stored in a 110℃ oven, and the solvent thermal reaction was carried out under the pressure generated by the glass vial for 16 h, after taking out and cooling, the product was collected, washed with DMF and dried, to obtain an indium-based metal organic framework material, which was a colorless hexagonal prism crystal.
[0052] The electron microscope photo of the indium-based metal organic framework material prepared in this example is shown in Figure 1 , the crystal structure is shown in Figure 2 , the powder X-ray diffraction pattern and the single crystal structure simulation PXRD pattern are shown in Figure 3 . According to Figure 1 , it can be seen that the indium-based metal organic framework material prepared in this example is a colorless hexagonal prism crystal. According to Figure 2 , it can be seen that the indium-based metal organic framework material prepared in this example has two kinds of cage structures. According to Figure 3 , it can be seen that the indium-based metal organic framework material prepared in this example has characteristic diffraction peaks of simulated single crystal structure, which indicates that the indium-based metal organic framework material prepared in this example has a crystal structure consistent with that obtained by actual single crystal X-ray diffraction, and has high crystallinity.
[0053] Test Example 1
[0054] Firstly, the indium-based metal organic framework material was activated, and dichloromethane was exchanged for 3 days, with an interval of 2 hours each time. The activated product was subjected to a 10 h degassing treatment under vacuum at 150℃, and the specific surface area performance test was carried out, which was a 77K nitrogen isothermal adsorption test, and the results are shown in Figure 4 . According to Figure 4It can be seen that the nitrogen adsorption curve is a typical type I curve, and the BET specific surface area is 910 m 2 / g.
[0055] Test Example 2
[0056] Using the activated product of Test Example 1, the ethane and ethylene adsorption capacity of the indium-based metal-organic framework material was tested: the single-component adsorption isotherms of ethane and ethylene of the indium-based metal-organic framework material were tested at 298 K, and the results are shown in Figure 5 According to Figure 5 It can be seen that, at 298 K and 1 bar, the adsorption capacity of the indium-based metal-organic framework material of the present application for ethane is 60 cm 3 g -1 , and the adsorption capacity for ethylene is 53.7 cm 3 g -1 .
[0057] Figure 6 The adsorption selectivity curve of the indium-based metal-organic framework material prepared in Example 1 for the two gases when the ethane / ethylene volume ratio is 50:50 was calculated by IAST. According to Figure 6 It can be seen that, at 298 K and 1 bar, the selectivity of ethane / ethylene (C2H6 / C2H4, v / v, 50:50) is 1.7, which is good.
[0058] From the above examples, it can be seen that the indium-based metal-organic framework material provided by the present application has high crystallinity, large specific surface area, good ability to selectively separate ethane and ethylene, high adsorption capacity, small adsorbent dosage, low cost, and realizes effective purification of ethylene.
[0059] Although the above examples have made a detailed description of the present application, it is only a part of the embodiments of the present application, not all the embodiments, and other embodiments can be obtained according to the present embodiments without creativity, and these embodiments all belong to the protection scope of the present application.
Claims
1. An indium-based metal-organic framework material, characterized in that: The preparation method comprises the following steps: An indium salt, an organic ligand, nitric acid and a solvent are mixed to undergo a solvothermal reaction to obtain an indium-based metal-organic framework material; The organic ligands are sodium tris(1H-imidazol-1-yl)borohydride and terephthalic acid; The indium salt is a soluble indium salt; the soluble indium salt is one or more of indium chloride, indium bromide, indium acetate and indium nitrate; The molar ratio of the indium salt to sodium tri(1H-imidazol-1-yl)borohydride is 1:1-5; the molar ratio of the indium salt to terephthalic acid is 1-3:1; The solvent thermal reaction temperature is 80-160°C; the heat preservation reaction time is 8-24h; The solvent includes an amide solvent and a low-boiling-point solvent; the volume ratio of the amide solvent to the low-boiling-point solvent is 1-4:1; and the low-boiling-point solvent is one or more of water, acetonitrile, methanol and ethanol.
2. The indium-based metal-organic framework material according to claim 1, characterized in that The molar ratio of the sodium tris(1H-imidazol-1-yl)borohydride to terephthalic acid is 1-3:
1.
3. The indium-based metal-organic framework material according to claim 1, characterized in that The specific surface area of the indium-based metal organic framework material is 700-1200 m 2 / g, pore volume is 0.2~0.5cm 2 / g, porosity is 70~95%.
4. The method for preparing the indium-based metal-organic framework material according to any one of claims 1 to 3, characterized in that: The following steps are involved: An indium salt, an organic ligand, nitric acid and a solvent are mixed to undergo a solvothermal reaction to obtain an indium-based metal-organic framework material; The organic ligands are sodium tris(1H-imidazol-1-yl)borohydride and terephthalic acid; The indium salt is a soluble indium salt; the soluble indium salt is one or more of indium chloride, indium bromide, indium acetate and indium nitrate; The molar ratio of the indium salt to sodium tri(1H-imidazol-1-yl)borohydride is 1:1-5; the molar ratio of the indium salt to terephthalic acid is 1-3:1; the temperature of the solvent thermal reaction is 80-160° C.; and the heat preservation reaction time is 8-24 hours; The solvent includes an amide solvent and a low-boiling-point solvent; the volume ratio of the amide solvent to the low-boiling-point solvent is 1-4:1; and the low-boiling-point solvent is one or more of water, acetonitrile, methanol and ethanol.
5. The preparation method according to claim 4, characterized in that The ratio of the amount of the indium salt to the volume of the solvent is (0.01-0.1) mmol: (1-4) mL.
6. The preparation method according to claim 4, characterized in that The solvothermal reaction is carried out under closed conditions.
7. Use of the indium-based metal-organic framework material according to any one of claims 1 to 3 or the indium-based metal-organic framework material obtained by the preparation method according to any one of claims 4 to 6 in the field of separation and purification of ethylene.
8. The use according to claim 7, characterized in that The indium-based metal organic framework material is activated before use; the activation comprises the following steps: The indium-based metal organic framework material is solvent exchanged and then degassed and activated.
9. The use according to claim 8, characterized in that The solvent for the solvent exchange is dichloromethane; the frequency of the solvent exchange is once every 1 to 3 hours, and the total exchange time is 3 to 5 days.
10. The use according to claim 8, characterized in that The degassing activation temperature is 80-150° C., and the activation time is 8-12 hours; the degassing activation is carried out in dry conditions.