Ionic liquid supported metal-organic framework composite dehumidifier and method of making same

Abstract

The application discloses an ionic liquid loaded metal framework organic compound composite dehumidifier and a preparation method thereof. The ionic liquid loaded metal framework organic compound composite dehumidifier comprises a metal framework organic compound and ionic liquid loaded on the metal framework organic compound, the metal framework organic compound is MIL-101, the ionic liquid is 1-ethyl acetate group-3-methyl imidazole tetrafluoroborate, and the mass ratio of the ionic liquid to the metal framework organic compound is 1:1-3:1. The ionic liquid loaded metal framework organic compound composite dehumidifier provided by the application has small corrosion and high efficient dehumidification function, the reagent used in the preparation method is easy to obtain, is non-toxic and harmless, the process is simple, and the ionic liquid loaded metal framework organic compound composite dehumidifier is easy to mass produce and realize industrialization.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of ionic liquid load metal framework organic compound composite dehumidifier and its preparation method. BACKGROUND

[0002] The energy consumption of air conditioning system is increasing day by day. In order to reduce energy consumption, many scholars have studied the temperature and humidity independent control system, in which the solid dehumidification air conditioning system is a kind of temperature and humidity independent control air conditioning system. The solid dehumidification air conditioning system combines the solid desiccant dehumidification device with the traditional refrigeration system (such as vapor compression refrigeration system, vapor absorption refrigeration system), and the dehumidification device realizes humidity control and the refrigeration system realizes temperature control. The solid dehumidification device usually uses low-grade energy (solar energy, waste heat, waste heat, etc.) as the driving energy, which greatly reduces the energy consumption and reduces environmental pollution. The solid dehumidification device can be divided into fixed bed type and rotary type, which uses the water absorption characteristics of solid desiccant to realize efficient control of humidity, and the physical properties of solid desiccant have an important influence on the dehumidification performance and regeneration performance of the system. Solid desiccant can be divided into physical desiccant (silica gel, activated carbon, zeolite, activated alumina, etc.) and chemical desiccant (LiCl, CaCl2, etc.), the former has a higher regeneration temperature and lower moisture absorption capacity; the latter has a strong moisture absorption capacity, but can cause equipment corrosion, thereby reducing the dehumidification capacity of the system. Therefore, scholars usually compound physical and chemical desiccants to prepare a composite that has the advantages of both: low regeneration temperature, high dehumidification capacity, and no corrosion of equipment, so as to ensure the normal operation of the dehumidification system. Therefore, it has become a research hotspot to develop a composite desiccant material with high moisture absorption capacity and low regeneration temperature to improve the efficiency of the dehumidification system.

[0003] The composite desiccant is generally a hygroscopic salt (such as LiCl, CaCl2, MgCl2, LiBr, etc.) impregnated into the pore structure of a porous desiccant. The hygroscopic salt usually has strong water absorption capacity, but it is easily soluble in water and unstable in nature, so a stable porous desiccant such as silica gel, activated carbon, molecular sieve, etc. is used as the matrix, which can greatly enhance the stability of the adsorbent. A new type of coordination polymer, metal organic framework material (MOFs), has gradually become a research hotspot, which has a large specific surface area and strong moisture absorption capacity.

[0004] Addition of hygroscopic salts in solid desiccants is an effective way to improve the adsorption performance of traditional porous adsorbents. Various composite adsorbents using modified silica-based matrices have been developed for dehumidification and have demonstrated significantly improved adsorption capacity. But the potential strong corrosive risk of these salts to metal components such as pipes and heat exchangers limits their practical application. Subsequently, organic weak acid salts such as potassium formate and sodium acetate are used to prepare composite adsorbents, but at the expense of adsorption capacity to some extent. Therefore, finding a material with high hydrophilicity and no corrosion is a necessary condition to achieve the goal of improving adsorption capacity and at the same time maintaining safety and stability. SUMMARY

[0005] In order to solve the problem of efficient and green dehumidification in current life and industry, the application provides a composite dehumidifier of ionic liquid loaded metal framework organic compound with low corrosion and efficient dehumidification function and a preparation method thereof.

[0006] In order to achieve the above application purposes, the application adopts the following technical solutions:

[0007] In the first aspect, the application provides a composite dehumidifier of ionic liquid loaded metal framework organic compound, which comprises a metal framework organic compound and ionic liquid loaded on the metal framework organic compound, the metal framework organic compound is MIL-101, and the ionic liquid is 1-ethyl acetate group-3-methyl imidazole tetrafluoroborate ([EOOEMIm][BF4]), wherein the mass ratio of the ionic liquid to the metal framework organic compound is 1:1-3:1.

[0008] As a preferred, the composite dehumidifier of ionic liquid loaded metal framework organic compound is composed of a metal framework organic compound and ionic liquid loaded on the metal framework organic compound.

[0009] In the second aspect, the application provides a preparation method of the composite dehumidifier of ionic liquid loaded metal framework organic compound, and the preparation method is implemented as follows:

[0010] Step one: dissolve the ionic liquid in deionized water, stir uniformly, and obtain an ionic liquid solution;

[0011] Step two: add the metal framework organic compound MIL-101 in the ionic liquid solution obtained in step one, and put it into an ultrasonic device for ultrasonic treatment to make it homogeneous;

[0012] Step three: transfer the fully dispersed mixture into a vacuum oven to completely evaporate the remaining water, and obtain the composite dehumidifier of ionic liquid loaded metal framework organic compound.

[0013] The metal framework organic matter MIL-101 described in the application can be prepared by the method reported in the prior art. Preferably, the metal framework organic matter is washed with N,N-dimethylformamide (DMF) and ethanol solvent respectively before loading the ionic liquid, and then dried after washing.

[0014] Preferably, in step one, the mass ratio of [EOOEMIm][BF4] to deionized water is 1:0.8-1.5, more preferably 1:1.

[0015] Preferably, in step one, the stirring condition is that the stirring speed of magnetic stirring is 300 r / min, the temperature is room temperature, and the time is 20 min.

[0016] Preferably, in step two, the temperature of the ultrasonic device is room temperature, and the ultrasonic time is 1-5 h. Within the time range, prolonging the ultrasonic time helps to improve the performance of the dehumidifier.

[0017] Preferably, in step three, the temperature of vacuum drying is 100-140℃, and the drying time is 10-15 h; more preferably, the temperature is 120℃, and the time is 12 h.

[0018] Compared with the prior art, the application has the following innovations and technical advantages:

[0019] (1) The preparation method of the ionic liquid loaded metal framework organic compound composite dehumidifier adopted in the application uses wet impregnation method to prepare the composite dehumidifier, which is simple to operate, low in cost, and convenient for industrial production; and the use of ultrasonic method can make the ionic liquid more uniformly loaded on the metal framework organic matter. In general, the method of the application uses reagents that are easy to obtain, non-toxic and harmless, simple in process, and easy to mass produce and realize industrialization.

[0020] (2) The specific ester-functionalized imidazole ionic liquid adopted in the application has great dehumidification potential, but its melting point is low, viscosity is high, and mass transfer is poor. The application of the application overcomes the above limitations by impregnating the ionic liquid into the metal framework organic matter MIL-101 which has porous properties, large specific surface area, high porosity, controllable pore structure and adjustable pore surface to prepare a supported ionic liquid, greatly enhancing the water absorption capacity and successfully applying it to the field of water absorption related fields. The ionic liquid loaded activated carbon fiber composite dehumidifier prepared by the application has strong water absorption capacity, is green and non-corrosive when applied to dehumidification. DETAILED DESCRIPTION

[0021] The application will be described in detail below with specific examples. It is necessary to point out that the examples are only used to further illustrate the application, but cannot be understood as limiting the protection scope of the application, and the application is not limited in any way. Those skilled in the art can make some non-essential improvements and adjustments according to the content of the above application.

[0022] Unless otherwise indicated, the embodiments described herein were conducted under conventional conditions or manufacturer's recommended conditions. Unless otherwise indicated, the reagents or instruments used were conventional products available through routine techniques or commercially available.

[0023] Example 1

[0024] (1) Preparation of metal-organic framework

[0025] Synthesis of MIL-101 support, 3 mmol (0.5 g) of terephthalic acid (H2BDC) and 3 mmol (1.2 g) of Cr(NO3)3·9H2O were dissolved in 25 mL of deionized water, and 3 mmol of hydrofluoric acid (0.6 mL) was added, and stirred at room temperature for 2 h. Subsequently, the resulting green mixed solution was transferred to a 50 mL high-pressure reaction kettle, and a hydrothermal reaction was performed at 493 K in an oven for 8 h. After the reaction was completed and the reaction kettle was slowly cooled to room temperature, the resulting green solution was filtered with a large-pore sand core funnel and repeatedly washed with ethanol and deionized water. Then the filtrate obtained in the previous step was filtered again with a small-pore sand core funnel to obtain a green MIL-101 solid. The green MIL-101 solid powder prepared as described above was uniformly dispersed in 40 mL of DMF solvent and refluxed for 48 h to sufficiently remove the residual H2BDC in the pores. After the reflux was completed, the solid was filtered and washed with N,N-dimethylformamide (DMF) and ethanol solvents, respectively, and finally the obtained solid was dried in an oven at 430 K overnight to obtain a green powder solid which was placed in a desiccator for use.

[0026] (2) Preparation of composite dehumidifier

[0027] [EOOEMIm][BF4] was dissolved in deionized water (mass ratio 1:1), and stirred at room temperature with a magnetic stirrer (speed 300 r / min) for 20 min. The metal-organic framework MIL-101 was added to the solution (mass ratio of ionic liquid to MIL-101 was 1:1), and placed in an ultrasonic device for 1 h to make it homogeneous. Then the well-dispersed mixture was transferred to a vacuum oven at a temperature of 120°C and dried for 12 h to completely evaporate the remaining water. The synthesized white solid was obtained, and then ground into powder.

[0028] (3) The water absorption capacity of the composite dehumidifier was determined by a water absorption analyzer.

[0029] The water absorption rate of the composite dehumidifier is 0.80 g / g under the reaction condition of temperature 20℃, 60% RH, and adsorption time 6h. The water absorption rate of the composite dehumidifier is 1.23 g / g under the reaction condition of temperature 20℃, 80% RH, and adsorption time 24h.

[0030] Example 2

[0031] Example 2 is used to illustrate the importance of using ultrasonic preparation method to prepare the composite dehumidifier by comparing with Example 1.

[0032] (1) Preparation of metal framework organic matter

[0033] Synthesis of MIL-101 carrier: 3 mmol (0.5 g) of terephthalic acid (H2BDC) and 3 mmol (1.2 g) of Cr(NO3)3·9H2O were dissolved in 25 mL of deionized water, and 3 mmol of hydrofluoric acid (0.6 mL) was added, and stirred at room temperature for 2 h. Subsequently, the obtained green mixed solution was transferred to a 50 mL high-pressure reaction kettle, and a hydrothermal reaction was carried out in a 493 K oven for 8 h. After the reaction was completed and the reaction kettle was slowly cooled to room temperature, the obtained green solution was filtered with a large aperture sand core funnel, and repeatedly washed with ethanol and deionized water. Then the filtrate obtained in the previous step was filtered again with a small aperture sand core funnel, thereby obtaining a green MIL-101 solid. The green MIL-101 solid powder prepared above was uniformly dispersed in 40 mL of DMF solvent, and was refluxed for 48 h to fully remove the residual H2BDC in the pores. After the reflux was completed, the solid was filtered and was fully washed with N,N-dimethylformamide (DMF) and ethanol solvents, respectively, and finally the obtained solid was placed in a 430 K oven to dry overnight, to obtain a green powder solid which was placed in a desiccator for standby.

[0034] (2) Preparation of composite dehumidifier

[0035] [EOOEMIm][BF4] was dissolved in deionized water (mass ratio 1:1), and was stirred at room temperature by a magnetic stirrer (rotation speed 300 r / min) for 20 min. The metal framework organic compound MIL-101 was added into the solution (mass ratio of ionic liquid to MIL-101 was 1:1), and was placed in an ultrasonic device to be homogenized for 3 h. Then the fully dispersed mixture was transferred into a vacuum oven to be dried at a temperature of 120℃ for 12 h to completely evaporate the remaining water. The synthesized white solid was obtained, and was then ground into powder.

[0036] (3) The water absorption capacity of the composite dehumidifier was determined by a water absorption analyzer.

[0037] The water absorption rate of the composite dehumidifier was 0.90 g / g under the reaction conditions of temperature 20°C, 60% RH, and adsorption time 6 h. The water absorption rate of the composite dehumidifier was 1.37 g / g under the reaction conditions of temperature 20°C, 80% RH, and adsorption time 24 h.

[0038] Example 3

[0039] (1) Preparation of metal framework organic matter

[0040] Synthesis of MIL-101 carrier: 3 mmol (0.5 g) of terephthalic acid (H2BDC) and 3 mmol (1.2 g) of Cr(NO3)3·9H2O were dissolved in 25 mL of deionized water, and 3 mmol of hydrofluoric acid (0.6 mL) was added, and stirred at room temperature for 2 h. Subsequently, the obtained green mixed solution was transferred to a 50 mL high-pressure reaction kettle, and a hydrothermal reaction was carried out at 493 K in an oven for 8 h. After the reaction was completed and the reaction kettle was slowly cooled to room temperature, the obtained green solution was filtered with a large-pore sand core funnel, and repeatedly washed with ethanol and deionized water. Then, the filtrate obtained in the above step was filtered again with a small-pore sand core funnel, to obtain a green MIL-101 solid. The green MIL-101 solid powder prepared above was uniformly dispersed in 40 mL of DMF solvent, and refluxed for 48 h, so as to fully remove the residual H2BDC in the pores. After the reflux was completed, the solid was filtered, and was fully washed with N,N-dimethylformamide (DMF) and ethanol solvents respectively, and finally the obtained solid was placed in an oven at 430 K for overnight drying, to obtain a green powder solid which was placed in a desiccator for standby use.

[0041] (2) Preparation of composite dehumidifier

[0042] [EOOEMIm][BF4] was dissolved in deionized water (mass ratio 1:1), and stirred at room temperature by a magnetic stirrer (rotation speed 300 r / min) for 20 min. The metal framework organic compound MIL-101 was added in the solution (mass ratio of ionic liquid to MIL-101 2:1), and was placed in an ultrasonic device for 3 h, so as to make it homogeneous. Then, the fully dispersed mixture was transferred to a vacuum oven for drying at a temperature of 120°C for 12 h, so as to completely evaporate the remaining water. The synthesized white solid was obtained, and was then ground into powder.

[0043] (3) The water absorption capacity of the composite dehumidifier was determined by a water absorption analyzer.

[0044] The water absorption rate of the composite dehumidifier was 0.98 g / g under the reaction conditions of temperature 20°C, 60% RH, and adsorption time 6 h. The water absorption rate of the composite dehumidifier was 1.53 g / g under the reaction conditions of temperature 20°C, 80% RH, and adsorption time 24 h.

[0045] Example 4

[0046] (1) Preparation of metal-organic framework

[0047] Synthesis of MIL-101 support, 3 mmol (0.5 g) of terephthalic acid (H2BDC) and 3 mmol (1.2 g) of Cr(N03)3-9H20 were dissolved in 25 mL of deionized water, and 3 mmol of hydrofluoric acid (0.6 mL) was added, and stirred at room temperature for 2 h. Subsequently, the resulting green mixed solution was transferred to a 50 mL high-pressure reaction kettle, and a hydrothermal reaction was performed at 493 K in an oven for 8 h. After the reaction was completed and the reaction kettle was slowly cooled to room temperature, the resulting green solution was filtered with a large-pore sand core funnel and repeatedly washed with ethanol and deionized water. Then, the filtrate obtained in the previous step was filtered again with a small-pore sand core funnel, thereby obtaining a green MIL-101 solid. The green MIL-101 solid powder prepared as described above was uniformly dispersed in 40 mL of a DMF solvent and refluxed for 48 h, thereby sufficiently removing residual H2BDC in the pores. After the reflux was completed, the solid was filtered and sufficiently washed with N,N-dimethylformamide (DMF) and ethanol solvents, respectively, and finally the obtained solid was dried in an oven at 430 K overnight to obtain a green powder solid which was stored in a desiccator.

[0048] (2) Preparation of composite desiccant

[0049] [EOOEMIm][BF4] was dissolved in deionized water (mass ratio of 1:1), and stirred at room temperature with a magnetic stirrer (rotation speed of 300 r / min) for 20 min. The metal-organic framework MIL-101 was added to the solution (mass ratio of ionic liquid to MIL-101 of 3:1), and placed in an ultrasonic device, and ultrasonically homogenized for 3 h. After that, the well-dispersed mixture was transferred to a vacuum oven and dried at a temperature of 120°C for 12 h to completely evaporate the remaining water. The synthesized white solid was obtained, and then ground into a powder.

[0050] (3) The water absorption capacity of the composite desiccant was determined by a water absorption analyzer.

[0051] Under the reaction conditions of a temperature of 20°C, 60% RH, and an adsorption time of 6 h, the water absorption rate of the composite desiccant was 1.25 g / g. Under the reaction conditions of a temperature of 20°C, 80% RH, and an adsorption time of 24 h, the water absorption rate of the composite desiccant was 1.76 g / g.

[0052] Comparative Example 1

[0053] Comparative Example 1 is to illustrate the importance of the selection of the metal- framework organic compound on the dehumidifying capacity of the dehumidifier by comparing with Example 1.

[0054] (1) Preparation of the composite dehumidifier

[0055] [EOOEMIm][BF4] was dissolved in deionized water (mass ratio 1:1) and stirred by a magnetic stirrer (300 r / min) at room temperature for 20 min. The metal- framework organic compound MCM-41 was added into the solution (mass ratio of the ionic liquid to MCM-41 was 1:1) and put into an ultrasonic device for 1 h to make it homogeneous. Then the well-dispersed mixture was transferred into a vacuum oven to dry at 120 °C for 12 h to make the residual water completely evaporate. The synthesized white solid was obtained and then ground into powder.

[0056] (2) The water absorption capacity of the composite dehumidifier was determined by the water absorption analyzer

[0057] The water absorption rate of the composite dehumidifier was 0.43 g / g under the reaction condition of temperature 20 °C, 60% RH and adsorption time 6 h. The water absorption rate of the composite dehumidifier was 0.61 g / g under the reaction condition of temperature 20 °C, 80% RH and adsorption time 24 h.

[0058] Comparative Example 2

[0059] Comparative Example 2 is to illustrate the importance of the selection of the ester- functionalized imidazolium-based ionic liquid on its dehumidifying capacity by comparing with Example 1.

[0060] (1) Preparation of the metal- framework organic compound

[0061] Synthesis of MIL-101 support, 3 mmol (0.5 g) of terephthalic acid (H2BDC) and 3 mmol (1.2 g) of Cr(N03)3.9H20 were dissolved in 25 mL of deionized water and 3 mmol of hydrofluoric acid (0.6 mL) was added and stirred for 2 h at room temperature. Subsequently, the resulting green mixed solution was transferred to a 50 mL high-pressure reactor and subjected to a hydrothermal reaction at 493 K for 8 h in an oven. After the reaction was completed and the reactor was slowly cooled to room temperature, the resulting green solution was filtered using a large-pore sand core funnel and repeatedly washed with ethanol and deionized water. Then, the filtrate obtained in the previous step was filtered again using a small-pore sand core funnel, thereby obtaining a green MIL-101 solid. The green MIL-101 solid powder prepared as described above was uniformly dispersed in 40 mL of a DMF solvent and subjected to reflux for 48 h, thereby sufficiently removing H2BDC remaining in the pores. After the reflux was completed, the solid was filtered and sufficiently washed with N,N-dimethylformamide (DMF) and an ethanol solvent, respectively, and the resulting solid was dried in an oven at 430 K overnight to obtain a green powder solid which was stored in a desiccator.

[0062] (2) Preparation of composite desiccant

[0063] CaCl2was dissolved in deionized water (mass ratio of 1:1) and stirred at room temperature using a magnetic stirrer (rotation speed of 300 r / min) for 20 min. MIL-101, a metal framework organic compound, was added to the solution in a mass ratio of 1:1 of CaCl2to MIL-101, and the mixture was homogenized by ultrasonic treatment for 1 h. The well-dispersed mixture was then transferred to a vacuum oven and dried at a temperature of 120 °C for 12 h to completely evaporate the remaining water. A synthesized white solid was obtained, which was then ground into a powder.

[0064] (3) The water absorption capacity of the composite desiccant was measured using a water absorption analyzer.

[0065] The water absorption rate of the composite desiccant was 0.61 g / g under the reaction conditions of a temperature of 20 °C, 60% RH, and an adsorption time of 6 h. The water absorption rate of the composite desiccant was 0.83 g / g under the reaction conditions of a temperature of 20 °C, 80% RH, and an adsorption time of 24 h.

[0066] Comparative Example 3

[0067] Comparative Example 3 illustrates the importance of selecting an ester-functionalized imidazolium ionic liquid for the desiccant capacity of the desiccant by comparison with Example 1.

[0068] (1) Preparation of metal framework organic compound

[0069] Synthesis of MIL-101 support, 3 mmol (0.5 g) of terephthalic acid (H2BDC) and 3 mmol (1.2 g) of Cr(N03)3.9H20 were dissolved in 25 mL of deionized water and 3 mmol of hydrofluoric acid (0.6 mL) was added and stirred for 2 h at room temperature. Subsequently, the resulting green mixed solution was transferred to a 50 mL high-pressure reactor and subjected to a hydrothermal reaction at 493 K for 8 h in an oven. After the reaction was completed and the reactor was slowly cooled to room temperature, the resulting green solution was filtered using a large-pore sand core funnel and repeatedly washed with ethanol and deionized water. Then, the filtrate obtained in the previous step was filtered again using a small-pore sand core funnel, thereby obtaining a green MIL-101 solid. The green MIL-101 solid powder prepared as described above was uniformly dispersed in 40 mL of a DMF solvent and subjected to reflux for 48 h, thereby sufficiently removing H2BDC remaining in the pores. After the reflux was completed, the solid was filtered and sufficiently washed with N,N-dimethylformamide (DMF) and an ethanol solvent, respectively, and the resulting solid was dried in an oven at 430 K overnight, thereby obtaining a green powder solid which was stored in a desiccator.

[0070] (2) Preparation of the composite desiccant

[0071] [Bmim][BF4] was dissolved in deionized water (mass ratio of 1:1) and stirred at room temperature using a magnetic stirrer (rotation speed of 300 r / min) for 20 min. MIL-101, a metal framework organic compound, was added to the solution (mass ratio of 1:1 of ionic liquid to MIL-101), and the mixture was homogenized by ultrasonication for 1 h. The well-dispersed mixture was then transferred to a vacuum oven and dried at a temperature of 120 °C for 12 h to completely evaporate the remaining water. The synthesized white solid was then ground into a powder.

[0072] (3) The water absorption capacity of the composite desiccant was measured using a water absorption analyzer.

[0073] The water absorption rate of the composite desiccant was 0.66 g / g under the reaction conditions of a temperature of 20 °C, 60% RH, and an adsorption time of 6 h. The water absorption rate of the composite desiccant was 0.89 g / g under the reaction conditions of a temperature of 20 °C, 80% RH, and an adsorption time of 24 h.

[0074] Comparative Example 4

[0075] Comparative Example 4 illustrates the importance of selecting an ester-functionalized imidazolium-based ionic liquid for the desiccant capacity by comparing it with Example 1.

[0076] (1) Preparation of the metal framework organic compound

[0077] Synthesis of MIL-101 support, 3 mmol (0.5 g) of terephthalic acid (H2BDC) and 3 mmol (1.2 g) of Cr(NO3)3.9H2O were dissolved in 25 mL of deionized water, and 3 mmol of hydrofluoric acid (0.6 mL) was added, and stirred at room temperature for 2 h. Subsequently, the resulting green mixed solution was transferred to a 50 mL high-pressure reactor, and a hydrothermal reaction was performed at 493 K in an oven for 8 h. After the reaction was completed and the reactor was slowly cooled to room temperature, the resulting green solution was filtered with a large-pore sand core funnel and repeatedly washed with ethanol and deionized water. Then, the filtrate obtained in the previous step was filtered again with a small-pore sand core funnel, thereby obtaining a green MIL-101 solid. The green MIL-101 solid powder prepared as described above was uniformly dispersed in 40 mL of a DMF solvent and refluxed for 48 h, thereby sufficiently removing H2BDC remaining in the pores. After the reflux was completed, the solid was filtered and sufficiently washed with N,N-dimethylformamide (DMF) and ethanol solvents, respectively, and finally the obtained solid was dried in an oven at 430 K overnight to obtain a green powder solid which was stored in a desiccator.

[0078] (2) Preparation of the composite desiccant

[0079] [Bdmim][BF4] was dissolved in deionized water (mass ratio 1:1), and stirred at room temperature with a magnetic stirrer (rotation speed 300 r / min) for 20 min. MIL-101, a metal framework organic compound, was added to the solution (mass ratio of ionic liquid to MIL-101 1:1), and placed in an ultrasonic device, and ultrasonically homogenized for 1 h. The well-dispersed mixture was then transferred to a vacuum oven and dried at a temperature of 120°C for 12 h to completely evaporate the remaining water. The synthesized white solid was then ground into a powder.

[0080] (3) The water absorption capacity of the composite desiccant was measured using a water absorption analyzer.

[0081] Under the reaction conditions of a temperature of 20°C, 60% RH, and an adsorption time of 6 h, the water absorption rate of the composite desiccant was 0.68 g / g. Under the reaction conditions of a temperature of 20°C, 80% RH, and an adsorption time of 24 h, the water absorption rate of the composite desiccant was 0.90 g / g.

[0082] Comparative Example 5

[0083] Comparative Example 5 illustrates the importance of selecting an imidazolium-based ionic liquid of tetrafluorosilicate salt for the dehumidification capacity of the desiccant by comparison with Example 1.

[0084] (1) Preparation of metal framework organic compound

[0085] Synthesis of MIL-101 support, 3 mmol (0.5 g) of terephthalic acid (H2BDC) and 3 mmol (1.2 g) of Cr(N03)3.9H20 were dissolved in 25 mL of deionized water and 3 mmol of hydrofluoric acid (0.6 mL) was added, stirring at room temperature for 2 h. Subsequently, the resulting green mixed solution was transferred to a 50 mL high-pressure reactor, and a hydrothermal reaction was carried out at 493 K for 8 h in an oven. After the reaction was completed and the reactor was slowly cooled to room temperature, the resulting green solution was filtered with a large-pore sand core funnel and repeatedly washed with ethanol and deionized water. Then the filtrate obtained in the previous step was re-filtered with a small-pore sand core funnel to obtain a green MIL-101 solid. The green MIL-101 solid powder prepared above was uniformly dispersed in 40 mL of DMF solvent and refluxed for 48 h to sufficiently remove the residual H2BDC in the pores. After the reflux was completed, the solid was filtered and washed with N,N-dimethylformamide (DMF) and ethanol solvents, respectively, and finally the obtained solid was dried in an oven at 430 K overnight to obtain a green powder solid which was placed in a desiccator for use.

[0086] (2) Preparation of composite desiccant

[0087] [EOOEMIm][CI] was dissolved in deionized water (mass ratio 1:1), and stirred at room temperature with a magnetic stirrer (speed 300 r / min) for 20 min. MIL-101, a metal framework organic compound, was added to the solution (mass ratio of ionic liquid to MIL-101 was 1:1), and placed in an ultrasonic device for 1 h to make it homogeneous. The well-dispersed mixture was then transferred to a vacuum oven and dried at a temperature of 120°C for 12 h to completely evaporate the remaining water. The synthesized white solid was obtained and then ground into powder.

[0088] (3) The water absorption capacity of the composite desiccant was determined by a water absorption analyzer.

[0089] Under the reaction conditions of temperature 20°C, 60% RH, and adsorption time 6 h, the water absorption rate of the composite desiccant was 0.64 g / g. Under the reaction conditions of temperature 20°C, 80% RH, and adsorption time 24 h, the water absorption rate of the composite desiccant was 0.85 g / g.

Claims

1. An ionic liquid supported metal framework organic compound composite dehumidifier, characterized in that: The ionic liquid loaded metal framework organic compound composite dehumidifier comprises a metal framework organic compound and an ionic liquid loaded on the metal framework organic compound, the metal framework organic compound is MIL-101, and the ionic liquid is 1-ethyl acetate-3-methyl imidazole tetrafluoroborate, wherein the mass ratio of the ionic liquid to the metal framework organic compound is 1:1-3:

1.

2. The ionic liquid-loaded metal framework organic compound composite dehumidifier according to claim 1, characterized in that: The ionic liquid loaded metal framework organic compound composite dehumidifier is composed of a metal framework organic compound and an ionic liquid loaded on the metal framework organic compound.

3. A method for the preparation of an ionic liquid supported metal framework organic compound composite dehumidifier as claimed in claim 1 or 2, characterized by: The preparation method is implemented as follows: Step one: dissolve the ionic liquid in deionized water, stir uniformly, and obtain an ionic liquid solution; Step two: add the metal framework organic compound MIL-101 into the ionic liquid solution obtained in step one, and place into an ultrasonic device to make it homogeneous; Step three: transfer the fully dispersed mixture into a vacuum oven, make the remaining water completely evaporate, and obtain the ionic liquid loaded metal framework organic compound composite dehumidifier.

4. The production method according to claim 3, characterized by: In step one, the mass ratio of the ionic liquid to the deionized water is 1:0.8-1.

5.

5. The production method according to claim 3, characterized by: In step two, the temperature of the ultrasonic device is room temperature, and the ultrasonic time is 1-5 h.

6. The production method according to claim 3, wherein: In step three, the temperature of the vacuum drying is 100-140 DEG C, and the drying time is 10-15 h.