Device for preparing metal organic framework material by solvent method

Abstract

The utility model relates to a device for preparing a metal organic framework material by a solvent method, which comprises a reaction kettle, the reaction kettle is provided with a feed port for feeding reaction materials containing metal salt, organic ligand, solvent and carbon dioxide, the reaction condition is controlled to convert the carbon dioxide into a supercritical state, and the reaction materials react in the reaction kettle to obtain the metal organic framework material. Reaction liquid containing the metal organic framework material and a solvent is obtained; the device further comprises a first separator, a filter, a second separator, a solvent recovery tank for recovering a solvent and a carbon dioxide recovery tank for recovering carbon dioxide gas. According to the utility model, the metal organic framework material is prepared by adopting a solvent method, supercritical carbon dioxide is combined and used, the support of a porous carrier is not needed, the metal organic framework material can be produced in batches, and carbon dioxide gas and a solvent are recovered for cyclic utilization after the reaction is finished, so that the consumption of a large amount of the solvent is avoided, and the production cost is greatly reduced.

Description

Technical Field

[0001] The utility model specifically relates to a device for preparing metal organic framework materials by a solvent method. Background Art

[0002] Metal-organic framework materials (MOFs), also known as porous coordination polymers, can be used as adsorption materials. They are crystalline porous materials composed of self-assembly of organic ligands and metal ions or metal clusters (also known as secondary building units, SBUs). They have high porosity and large specific surface area, diverse structures, and have a wide range of potential uses in many fields, including gas storage, gas adsorption and separation. At present, the most studied method is to directly synthesize MOFs in organic solvents by conventional heating or microwave irradiation at high temperatures. However, this method requires a large amount of organic solvents, is energy-consuming and time-consuming, and has low yields. Therefore, it is crucial to develop a green, efficient, and controllable batch preparation method.

[0003] Supercritical fluids (SCFs) have the advantages of both liquids and gases. Their density and solubility are close to those of liquids, and their viscosity and diffusion properties are close to those of gases. Among them, supercritical carbon dioxide (scCO2) has attracted widespread attention due to its mild critical conditions, stable properties, good safety, easy availability of raw materials, low cost, easy recycling, and green environmental protection. Its potential solubility makes it an attractive medium for the synthesis of porous materials. First, the use of scCO2 is a time-saving and material-saving method for MOFs synthesis. The unique properties of scCO2 can significantly shorten the reaction time. Second, chemical reactions under supercritical conditions can highly control the crystallization process to adjust the properties of the material. Third, compared with traditional organic solvents, CO2 can be easily removed by pressure relief. At present, there are some studies on the synthesis of MOFs materials using scCO2, including continuous flow reactor synthesis, which consumes a large amount of solvent. The reaction process is synthesized through solvent heat transfer. The reaction insulation time is short due to the influence of solvent mass transfer, and the product crystallization is poor. Summary of the invention

[0004] The technical problem to be solved by the utility model is to provide a device capable of batch preparing metal organic framework materials in view of the deficiencies of the prior art, and to avoid the problem of large amount of organic solvent consumed in the reaction, high energy consumption, time consumption and cost.

[0005] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0006] A device for preparing a metal organic framework material by a solvent method, comprising a reactor with a stirrer, the reactor having a feed port for feeding a reaction material comprising a metal salt, an organic ligand, a solvent and carbon dioxide into the reactor, controlling the reaction conditions so that the carbon dioxide is converted into a supercritical state, and allowing the reaction material to react in the reactor to obtain a reaction liquid comprising a metal organic framework material and a solvent;

[0007] The reactor is also provided with a gas outlet and a material outlet;

[0008] The device also includes a first separator, a filter, a second separator, a solvent recovery tank for recovering the solvent, and a carbon dioxide recovery tank for recovering the carbon dioxide gas;

[0009] The first separator is connected to the discharge port and the solvent recovery tank through pipelines, respectively, and the first separator is used to separate the metal organic framework material and the solvent, and the separated solvent enters the solvent recovery tank;

[0010] The filter is connected to the gas outlet and the second separator through pipelines respectively. The second separator is used to separate the solvent and the carbon dioxide gas. The second separator is also connected to the carbon dioxide recovery tank through a pipeline.

[0011] The filter is used to filter the metal organic framework material in the carbon dioxide gas, the second separator is used to intercept or adsorb the solvent in the carbon dioxide gas, and the separated carbon dioxide gas enters the carbon dioxide recovery tank.

[0012] In some specific embodiments, the reaction conditions are: temperature of 60-200° C. and pressure of 12-30 MPa.

[0013] In some specific embodiments, the second separator is a packed separator, and the packing is a molecular sieve or activated carbon. The molecular sieve used is, for example, 4A zeolite. The carbon dioxide gas is adsorbed by the second separator to separate the solvent in the gas.

[0014] In some embodiments, the device also includes a first storage tank for storing carbon dioxide gas, a second storage tank for storing a metal salt solution, and a third storage tank for storing an organic ligand solution, wherein the metal salt solution comprises a metal salt and a solvent, and the organic ligand solution comprises an organic ligand and a solvent, and the first storage tank, the second storage tank, and the third storage tank are respectively connected to the feed port through pipelines.

[0015] In some specific embodiments, the organic ligand is one or more organic compounds containing carboxylic acids and imidazole derivatives (terephthalic acid, 2,5-dihydroxyterephthalic acid, 1,3,5-benzenetricarboxylic acid, etc., 2-methylimidazole, tri-(4-imidazolylphenyl)amine, etc.), the metal salt is one or more salts containing cations such as copper ions, zinc ions, magnesium ions, cobalt ions, nickel ions, zirconium ions, chromium ions, etc., and the solvent is one or more combinations of methanol, ethanol, and deionized water.

[0016] In some specific embodiments, the first storage tank is connected to the feed port via a first pipeline, and a first delivery pump is disposed on the first pipeline.

[0017] In some specific embodiments, the first delivery pump is a pneumatic booster pump or an electric booster pump.

[0018] In some specific embodiments, the second storage tank is connected to the feed port via a second pipeline, the third storage tank is connected to the feed port via a third pipeline, and second delivery pumps are respectively provided on the second pipeline and the third pipeline;

[0019] Alternatively, the feed port is also connected to a liquid main pipeline for conveying liquid, the second storage tank is connected to the liquid main pipeline via a second pipeline, the third storage tank is connected to the liquid main pipeline via a third pipeline, and a second delivery pump is arranged on the liquid main pipeline.

[0020] In some specific embodiments, the second delivery pump is a high-pressure constant-flow pump.

[0021] In some specific embodiments, the device further comprises a temperature sensor for detecting the temperature in the reactor and a pressure sensor for detecting the pressure in the reactor.

[0022] In some embodiments, the first separator is a centrifuge.

[0023] In some specific embodiments, the device further comprises a fourth storage tank for storing the ionic liquid, the fourth storage tank being connected to the feed port via a fourth pipeline, and the first separator being a heating separation device having heating and condensing functions. The heating separation device is commercially available, and the reaction liquid containing the ionic liquid and the solvent is heated in the first separator, and the solvent is converted into a gaseous state by utilizing the boiling point difference between the solvent and the ionic liquid, and then condensed into a liquid state, so as to separate the solvent from the ionic liquid and the metal organic framework material, and the separated solvent is recycled and reused, and the separated composite of the ionic liquid and the metal organic framework material can be directly used as an adsorption material.

[0024] The fourth pipeline is provided with a third delivery pump, and the third delivery pump is a high-pressure constant-flow pump.

[0025] The ionic liquid is one or a combination of imidazole ionic liquid, pyridine ionic liquid, quaternary ammonium salt ionic liquid, quaternary phosphonium salt ionic liquid, etc.

[0026] In addition to scCO2, ionic liquids (ILs) are also a new type of green medium. Due to their extremely low vapor pressure, non-flammable and non-explosive properties, and adjustable structural design, they have been fully developed and applied in the fields of gas separation in recent years. However, the fluidity of IL itself and its high viscosity have hindered its further development.

[0027] In some embodiments of the present invention, IL is combined with MOFs material, and IL is used to regulate the pore structure and performance of MOFs material, that is, IL is introduced into the pores of MOFs material or dispersed on the surface of MOFs material; or IL is fully dispersed by using the large specific surface area of ​​MOFs material, which can greatly increase the contact area between IL and gas and improve the mass transfer rate. At the same time, the fluidity of IL itself can be improved under the action of scCO2.

[0028] In some specific embodiments, the reactor is a stainless steel high-pressure reactor.

[0029] The metal organic framework material prepared by the device of the utility model is applied to the capture of CO2, in order to obtain a more efficient CO2 adsorbent.

[0030] Due to the application of the above technical solution, the utility model has the following advantages compared with the prior art:

[0031] The device of the utility model adopts a solvent method to prepare a metal organic framework material, and at the same time, supercritical carbon dioxide is used in the preparation process, and the high fluidity of supercritical carbon dioxide for mass transfer and good solubility in raw materials are utilized to significantly shorten the reaction time and highly control the crystallization process, and no porous carrier support is required, so that the metal organic framework material can be mass-produced. At the same time, after the reaction is completed, the carbon dioxide can be easily removed and the carbon dioxide gas can be recovered by depressurizing, and the solvent can be recovered by separating the metal organic framework material and the solvent. The recovered carbon dioxide gas and solvent can be recycled, so a large amount of solvent consumption is avoided, and the production cost is greatly reduced.

[0032] The device of the utility model can realize mass production, reduce the use of solvents and improve the crystallinity of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic diagram of the structure of the device for preparing metal organic framework materials by the solvent method in Example 1;

[0034] Figure 2 This is a scanning electron microscope image of a metal organic framework material sample prepared using the device of Example 1;

[0035] Figure 3 is an X-ray diffraction pattern of a metal organic framework material sample prepared by the device of Example 1;

[0036] Figure 4 This is a schematic diagram of the structure of the device for preparing metal organic framework materials by solvent method in Example 2;

[0037] In the figure: 1, first storage tank; 2, second storage tank; 3, third storage tank; 4, first delivery pump; 5, second delivery pump; 6, reactor; 7, first separator; 8, filter; 9, second separator; 10, solvent recovery tank; 11, carbon dioxide recovery tank; 12, temperature sensor; 13, pressure sensor; 14, agitator; 15, fourth storage tank; 16, third delivery pump;

[0038] 1a, first pipeline; 1b, second pipeline; 1c, third pipeline; 1d, liquid main pipeline; 1e, fourth pipeline. DETAILED DESCRIPTION

[0039] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments:

[0040] Example 1

[0041] See also Figure 1 The device for preparing metal organic framework materials by solvent method provided in this embodiment includes a reactor 6 with a stirrer 14, and the reactor 6 has a feed port for feeding reaction materials containing metal salts, organic ligands, solvents and carbon dioxide into the reactor 6. The reaction conditions are controlled to convert the carbon dioxide into a supercritical state, and the reaction materials are reacted in the reactor 6 to obtain a reaction liquid containing metal organic framework materials and solvents.

[0042] The reactor 6 is also provided with an air outlet and a material outlet, wherein the material inlet and the air outlet are located at the top of the reactor 6, and the material outlet is located at the bottom of the reactor 6. The reactor 6 is a stainless steel high-pressure reactor.

[0043] The device also includes a first storage tank 1 for storing carbon dioxide gas, a second storage tank 2 for storing a metal salt solution, and a third storage tank 3 for storing an organic ligand solution. The metal salt solution contains a metal salt and a solvent, and the organic ligand solution contains an organic ligand and a solvent. The first storage tank 1, the second storage tank 2, and the third storage tank 3 are respectively connected to the feed port through pipelines, and the materials in the first storage tank 1, the second storage tank 2, and the third storage tank 3 enter the reactor 6 through the feed port.

[0044] The device further comprises a first separator 7, a filter 8, a second separator 9, a solvent recovery tank 10 for recovering the solvent and a carbon dioxide recovery tank 11 for recovering the carbon dioxide gas, wherein:

[0045] The first separator 7 is connected to the feed port and the solvent recovery tank 10 through pipelines. The first separator 7 is used to separate the metal organic framework material and the solvent. The separated solvent enters the solvent recovery tank 10. The solvent in the solvent recovery tank 10 can be recycled; the separated metal organic framework material is taken out from the first separator 7. The first separator 7 can be a centrifuge, for example.

[0046] The filter 8 is connected to the gas outlet and the second separator 9 through a pipeline, and the second separator 9 is used to separate the solvent and the carbon dioxide gas. The second separator 9 is also connected to the carbon dioxide recovery tank 11 through a pipeline; the filter 8 is used to filter the metal organic framework material in the carbon dioxide gas, and the second separator 9 is used to intercept or adsorb the solvent in the carbon dioxide gas. The separated carbon dioxide gas enters the carbon dioxide recovery tank 11, and the carbon dioxide gas in the carbon dioxide recovery tank 11 can be recycled. The second separator 9 can be a packed separator, and the packing can be 4A zeolite, for example.

[0047] The first storage tank 1 is connected to the feed port through a first pipeline 1a. A first delivery pump 4 is arranged on the first pipeline 1a. The first delivery pump 4 is a pneumatic booster pump driven by an air compressor. The driving pressure is 0.3-0.8 MPa and the maximum output pressure is 32 MPa.

[0048] The feed port is also connected to a liquid main pipeline 1d for conveying liquid. The second storage tank 2 is connected to the liquid main pipeline 1d through a second pipeline 1b. The third storage tank 3 is connected to the liquid main pipeline 1d through a third pipeline 1c. A second delivery pump 5 is arranged on the liquid main pipeline 1d. The second delivery pump 5 is a high-pressure constant-flow pump.

[0049] Valves are installed on all pipelines. The device also includes a temperature sensor 12 for detecting the temperature in the reactor 6 and a pressure sensor 13 for detecting the pressure in the reactor 6. The temperature in the reactor 6 is controlled to be 60-200°C, the pressure to be 12-30MPa, and the reaction time to be 1-24h, so that the carbon dioxide gas enters the reactor 6 and is converted into a supercritical fluid state.

[0050] Control the stirring speed to 300-1500rpm.

[0051] In the actual production process, after the carbon dioxide gas in the first storage tank 1 enters the reactor 6, it is converted into a supercritical fluid state under the reaction temperature and pressure, so that the reaction is carried out under supercritical conditions. After the reaction is completed, the reactor 6 is depressurized, and the carbon dioxide in the supercritical state is converted into gas and discharged from the reactor 6 from the gas outlet. The discharged carbon dioxide gas may carry a small amount of metal organic framework materials and solvents. After being filtered by the filter 8, the metal organic framework materials are intercepted by the filter 8, and the solvent is intercepted or adsorbed by the second separator 9 to separate the carbon dioxide gas. Finally, the carbon dioxide gas is recovered for easy recycling.

[0052] The reaction liquid containing the metal organic framework material in the reaction kettle 6 enters the centrifuge for centrifugal separation, and the separated solvent is recovered for recycling.

[0053] Both carbon dioxide gas and solvents can be recycled without causing secondary pollution, which is green and environmentally friendly.

[0054] In some specific applications, the metal salt may be one or a combination of magnesium nitrate hexahydrate, cobalt acetylacetonate, copper nitrate trihydrate, zinc nitrate hexahydrate, etc., the organic ligand may be one or more of 2-methylimidazole, 1,3,5-benzenetricarboxylic acid, 2,5-dihydroxyterephthalic acid, etc., and the solvent may be one or a combination of methanol, ethanol and deionized water.

[0055] The device is further described below through a specific application example.

[0056] use Figure 1 HKUST-1 was prepared by the device, and the specific method is as follows:

[0057] A copper nitrate trihydrate ethanol solution with a concentration of 0.18 g / ml is stored in the second storage tank 2, and a 1,3,5-benzenetricarboxylic acid ethanol solution with a concentration of 0.12 g / ml is stored in the third storage tank 3. The second delivery pump 5 is turned on to feed the metal salt solution and the organic ligand solution into the reactor 6 in sequence, and the molar ratio of the metal salt to the organic ligand is controlled to be 1:2. Stirring is turned on and the stirring rate is controlled to be 1000 rpm.

[0058] The first delivery pump 4 was turned on to introduce carbon dioxide gas into the reactor 6, and the temperature in the reactor 6 was controlled to be 80° C. and the pressure to be 15 MPa. The reaction was kept warm for 12 hours to prepare HKUST-1.

[0059] After the insulation reaction is completed, the reactor 6 is naturally cooled to room temperature and the exhaust valve is opened, and the carbon dioxide gas is recovered through the filter 8 and the second separator 9 through the outlet; after the gas is exhausted, the discharge port is opened to allow the reaction liquid to enter the first separator 7 for solid-liquid separation, the solvent liquid is recovered, and the solid product is collected after drying.

[0060] The prepared metal organic framework material samples were scanned by electron microscope, such as Figure 2 . And X-ray diffraction analysis was performed on the metal organic framework material samples, such as Figure 3 As shown, the quasi-cards come from the Cambridge Structural Database (CSD). Figure 2 and Figure 3 It can be seen that nano-scale crystal particles are generated and the crystal surface has a porous structure; the peak position is consistent with the standard card, the structure is consistent, and the product is HKUST-1.

[0061] The reactor 6 carries out the next batch of reactions, and the metal organic framework material can be produced in batches. The obtained metal organic framework material is used in the CO2 capture process, has high adsorption efficiency, can be recycled, and has good industrial application prospects.

[0062] Example 2

[0063] See also Figure 4 The device for preparing metal organic framework materials by solvent method provided in this embodiment has a structure basically the same as that of embodiment 1, except that: the device further includes a fourth storage tank 15 for storing ionic liquid, the fourth storage tank 15 is connected to the feed port of the reactor 6 through a fourth pipeline 1e, and a third delivery pump 16 is arranged on the fourth pipeline 1e, and the third delivery pump 16 is a high-pressure constant flow pump. The first separator 7 adopts a heating separation device, which has its own heating and condensing functions.

[0064] In practical application, on the basis of Example 1, the feeding of ionic liquid is increased, the ionic liquid is 1-ethyl-3-methylimidazolium bistrifluorocarbonimide salt, the feeding amount is 0.4ml / ml ethanol solution, and the reaction solution finally prepared contains metal organic framework material, ionic liquid and solvent. The solvent is separated by the first separator 7, and the solvent is recovered to obtain a composite material of ionic liquid and metal organic framework material (ILs@MOFs). The obtained composite material of ionic liquid and metal organic framework material can be directly used in the CO2 capture process, has high adsorption efficiency, and can be recycled.

[0065] It can be seen from the above examples that the pure MOF material powder is prepared in Example 1. The composite is prepared in Example 2, and the composite of Example 2 also has the following advantages: First, both IL and MOF can be used for CO2 adsorption. In practical applications, the powder needs to be fixed, and it can be directly dispersed in IL for direct use; second, IL is combined with MOFs material, and IL is used to regulate the pore structure and performance of MOFs material, that is, IL is introduced into the pores of MOFs material or dispersed on the surface of MOFs material; or the large specific surface area of ​​MOFs material is used to fully disperse IL, which can increase the adsorption amount on pure MOF / pure IL.

[0066] The above embodiments are only for illustrating the technical concept and features of the utility model, and their purpose is to enable people familiar with this technology to understand the content of the utility model and implement it accordingly. They cannot be used to limit the protection scope of the utility model. All equivalent changes or modifications made according to the spirit of the utility model should be included in the protection scope of the utility model.

Claims

1. A device for preparing metal organic framework materials by solvent method, comprising a reaction kettle with a stirrer, characterized in that: The reactor is provided with a feed port for introducing reaction materials including metal salt, organic ligand, solvent and carbon dioxide into the reactor, and the reaction conditions are controlled to convert the carbon dioxide into a supercritical state, and the reaction materials are reacted in the reactor to obtain a reaction solution including a metal organic framework material and a solvent; The reactor is also provided with a gas outlet and a material outlet; The device also includes a first separator, a filter, a second separator, a solvent recovery tank for recovering the solvent, and a carbon dioxide recovery tank for recovering the carbon dioxide gas; The first separator is connected to the discharge port and the solvent recovery tank through pipelines, respectively, and the first separator is used to separate the metal organic framework material and the solvent, and the separated solvent enters the solvent recovery tank; The filter is connected to the gas outlet and the second separator through pipelines respectively. The second separator is used to separate the solvent and the carbon dioxide gas. The second separator is also connected to the carbon dioxide recovery tank through a pipeline.

2. The device for preparing metal organic framework materials by solvent method according to claim 1, characterized in that: The reaction conditions are: temperature of 60-200° C. and pressure of 12-30 MPa.

3. The device for preparing metal organic framework materials by solvent method according to claim 1, characterized in that: The second separator is a filler-type separator, and the filler is a molecular sieve or activated carbon.

4. The device for preparing metal organic framework materials by solvent method according to claim 1, characterized in that: The device also includes a first storage tank for storing carbon dioxide gas, a second storage tank for storing a metal salt solution, and a third storage tank for storing an organic ligand solution. The metal salt solution contains a metal salt and a solvent, and the organic ligand solution contains an organic ligand and a solvent. The first storage tank, the second storage tank, and the third storage tank are respectively connected to the feed port through pipelines.

5. The device for preparing metal organic framework materials by solvent method according to claim 4, characterized in that: The first storage tank is connected to the feed port through a first pipeline, and a first delivery pump is arranged on the first pipeline.

6. The device for preparing metal organic framework materials by solvent method according to claim 5, characterized in that: The first delivery pump is a pneumatic booster pump or an electric booster pump.

7. The device for preparing metal organic framework materials by solvent method according to claim 5, characterized in that: The second storage tank is connected to the feed port via a second pipeline, the third storage tank is connected to the feed port via a third pipeline, and second delivery pumps are respectively provided on the second pipeline and the third pipeline; Alternatively, the feed port is also connected to a liquid main pipeline for conveying liquid, the second storage tank is connected to the liquid main pipeline via a second pipeline, the third storage tank is connected to the liquid main pipeline via a third pipeline, and a second delivery pump is arranged on the liquid main pipeline.

8. The device for preparing metal organic framework materials by solvent method according to claim 7, characterized in that: The second delivery pump is a high-pressure constant-flow pump.

9. The device for preparing metal organic framework materials by solvent method according to any one of claims 1 to 8, characterized in that: The device further comprises a fourth storage tank for storing ionic liquid, wherein the fourth storage tank is connected to the feed port via a fourth pipeline, and the first separator is a heating separation device.

10. The device for preparing metal organic framework materials by solvent method according to claim 1, characterized in that: The device further comprises a temperature sensor for detecting the temperature in the reactor and a pressure sensor for detecting the pressure in the reactor; and / or the first separator is a centrifuge.

Images