Metal organic framework composite moisture absorbing body, moisture absorbing system and control method

Abstract

This invention relates to a metal-organic framework (MOF) composite hygroscopic body, a hygroscopic system, and a control method, comprising: a fiberglass mat matrix; a MOF material loaded on the surface and within the pores of the fiberglass mat matrix; and a microwave-responsive enhancement layer distributed within and / or on the surface of the MOF material. Compared with existing technologies, the MOF composite hygroscopic body of this invention has a high hygroscopic capacity. Combined with a hygroscopic system and control method adapted to this MOF composite hygroscopic body, rapid, uniform, and low-energy-consumption desorption and regeneration are achieved, and good cycle stability is also observed.

Description

Technical Field

[0001] This invention relates to the field of metal-organic framework materials, and more particularly to a metal-organic framework composite moisture absorber, a moisture absorption system, and a control method. Background Technology

[0002] Air desiccation technology has wide applications in agricultural greenhouses, pharmaceutical storage, electronic component manufacturing, and compressed air drying. Traditional desiccation methods mainly use desiccant materials such as silica gel, molecular sieves, or lithium chloride, but these materials generally suffer from problems such as low desiccant capacity, high regeneration temperature, and high regeneration energy consumption.

[0003] Metal-organic frameworks (MOFs) are a new type of porous material characterized by high specific surface area, tunable pore structure, and large water vapor adsorption capacity. Among them, materials such as MOF-808 can achieve efficient moisture absorption at low relative humidity and have a regeneration temperature as low as 70℃, which is a significant advantage over traditional silica gel (regeneration temperature 120-150℃).

[0004] However, MOF materials are usually in powder form, which leads to problems such as poor flowability, easy agglomeration, and low heat and mass transfer efficiency in practical applications. Although there have been attempts to load MOFs onto substrates in existing technologies, these generally suffer from low loading, poor bonding strength, and insufficient regeneration efficiency. Summary of the Invention

[0005] The first technical problem to be solved by the present invention is to provide a metal-organic framework composite moisture absorber with a large MOF loading, in light of the current state of the technology.

[0006] The second technical problem to be solved by the present invention is to provide a metal-organic framework composite moisture absorber with large MOF loading and large moisture absorption capacity, in view of the current state of the technology.

[0007] The third technical problem to be solved by the present invention is to provide a metal-organic framework composite moisture absorber with high MOF bonding strength and stable structure, in light of the current state of the technology.

[0008] The fourth technical problem to be solved by the present invention is to provide a metal-organic framework composite moisture absorber with good cycle stability, in light of the current state of the technology.

[0009] The fifth technical problem to be solved by the present invention is to provide a metal-organic framework composite moisture absorber with high regeneration efficiency, in light of the current state of the technology.

[0010] The sixth technical problem to be solved by the present invention is to provide a metal-organic framework composite moisture absorber with low regeneration energy consumption, in light of the current state of the technology.

[0011] The seventh technical problem to be solved by the present invention is to provide a moisture absorption system including the above-mentioned metal-organic framework composite moisture absorber, in view of the current state of the prior art.

[0012] The eighth technical problem to be solved by the present invention is to provide a control method for the above-mentioned moisture absorption system in light of the current state of the technology.

[0013] The technical solution adopted by the present invention to solve at least one of the above-mentioned technical problems is: a metal-organic framework composite moisture absorber, characterized in that it comprises:

[0014] Fiberglass mat matrix;

[0015] Metal-organic framework material is loaded onto the surface and internal pores of the fiberglass felt matrix;

[0016] A microwave response enhancement layer is distributed within and / or on the surface of the metal-organic framework material.

[0017] Furthermore, the porosity of the fiberglass mat matrix is ​​60%~90%, and the fiber diameter is 5μm~20μm. The high porosity provides sufficient internal space for in-situ growth of MOF crystals and water vapor diffusion channels, avoiding insufficient MOF loading due to excessively low porosity.

[0018] Furthermore, the loading of the metal-organic framework material is 30% to 80% of the mass of the fiberglass felt matrix. When the loading is less than 30 wt%, the adsorption capacity per unit volume is insufficient, resulting in poor dehumidification efficiency; when it is greater than 80 wt%, the MOF crystals are prone to clogging the pores of the fiberglass felt or peeling off, increasing airflow resistance and reducing mechanical stability.

[0019] Furthermore, the metal-organic framework material is , , , At least one of the above four MOF materials. All four MOF materials have abundant metal open sites and high specific surface area, enabling them to efficiently capture water molecules at room temperature, and are suitable for the moisture absorption system of this invention.

[0020] Furthermore, the microwave response enhancement layer is composed of a microwave response enhancement additive, which is... Nanoparticles and / or ionic liquids, wherein the ionic liquid is selected from at least one of 1-butyl-3-methylimidazolium tetrafluoroborate and 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide.

[0021] Furthermore, the aforementioned The particle size of the nanoparticles ranges from 10 nm to 50 nm.

[0022] Furthermore, the metal-organic framework composite moisture absorber is prepared through the following steps:

[0023] (1) Pretreatment: Dry the glass fiber mat at 80℃~120℃ for 2h~4h to remove surface moisture, and then place it in a plasma treatment device and treat it in an oxygen atmosphere for 3min~10min to introduce hydroxyl functional groups on the glass fiber surface.

[0024] (2) Seed impregnation: The pretreated glass fiber mat is immersed in a precursor solution containing a metal source, an organic ligand and a microwave response enhancement agent. The precursor solution is ultrasonically treated for 10 min to 30 min to fully wet the internal pores of the glass fiber.

[0025] (3) In-situ synthesis: The impregnated glass fiber mat is placed in a microwave reactor and reacted at 100℃~150℃ for 15min~60min, so that the metal-organic framework material grows in situ on the surface and in the internal pores of the glass fiber mat and forms a composite structure containing microwave response enhancer.

[0026] (4) Activation treatment: The synthesized composite material is washed with organic solvent and vacuum dried at 80℃~130℃ for 12h~24h to obtain the desired metal-organic framework composite hygroscopic body.

[0027] Furthermore, the precursor solution comprises: 1mmol / L~15mmol / L 1mmol / L~15mmol / L The nanoparticles are 0.1wt%~1wt%, the ionic liquid is 1wt%~10wt%, and the solvent is a mixture of N,N-dimethylformamide and formic acid.

[0028] The technical solution adopted to further solve the seventh technical problem mentioned above is: a moisture absorption system, characterized in that it includes a magnetron, a waveguide assembly, a resonant container, and a metal-organic framework composite moisture absorber as described above;

[0029] The waveguide assembly is connected between the output end of the magnetron and the resonant container, used to guide the microwave energy generated by the magnetron into the resonant container; the resonant container is a hollow container with conductive inner walls, and the metal-organic framework composite hygroscopic body is housed within the cavity of the resonant container; and the internal dimensions of the resonant container ( It is adapted to microwave wavelengths, thus enabling the establishment of a stable microwave resonant field within the resonant container, allowing microwave energy to be concentrated and coupled to the microwave response enhancement layer in the metal-organic framework composite hygroscopic body. (and / or ionic liquids) to achieve selective, volumetric heating rather than solely relying on heat conduction, avoiding overheating and charring of the fiberglass felt matrix. The resonant container is equipped with a first vent that can be opened and closed to allow humid air to enter, and a second vent that can be opened and closed to allow dry air to exit. Thus, during the adsorption phase, the first vent is open while the second vent is closed, allowing the humid air to be treated to enter the resonant container through the first vent; during the desorption and regeneration phase, the first vent is closed while the second vent is open, allowing dry air to exit through the second vent. By opening and closing the first and second vents, the adsorption-regeneration cycle is switched.

[0030] Furthermore, a rotating platform is provided in the resonant container, and the metal-organic framework composite hygroscopic body is placed on the rotating platform and can rotate synchronously with the rotating platform. The rotating platform drives the metal-organic framework composite hygroscopic body to rotate, so that it periodically sweeps through regions with different field strengths, resulting in more uniform average absorption power, more thorough desorption, and less local charring.

[0031] Furthermore, a mode stirrer is configured in the resonant container. Microwaves form standing waves inside the resonant container, with high field strength at some locations (hot spots) and near-zero field strength at others (cold spots). The mode stirrer can agitate the microwave field distribution, reduce standing wave nodes, and improve the uniformity of the microwave field distribution within the resonant container.

[0032] Furthermore, it also includes a carrier gas supply unit for introducing carrier gas into the resonant container during the regeneration stage. By introducing carrier gas into the resonant container, the desorbed water vapor is carried away immediately, thereby accelerating regeneration and preventing re-adsorption and condensation backflow.

[0033] The technical solution adopted to further solve the eighth technical problem mentioned above is: a control method for the moisture absorption system as described above, characterized by comprising the following steps:

[0034] Step S1, Adsorption stage: Open the first air port and close the second air port to allow humid air to enter the resonant container and flow through the metal-organic framework composite absorbent, and use the metal-organic framework composite absorbent to adsorb water vapor in the humid air.

[0035] Step S2, Desorption Stage: When the metal-organic framework composite hygroscopic body is saturated with adsorption, the first air port is closed and the second air port is opened. Dry air is discharged from the second air port, and then carrier gas is introduced into the resonant container through the second air port. The magnetron is activated, and microwaves act on the metal-organic framework composite hygroscopic body through the resonant container, causing the adsorbed water molecules to vaporize and desorb.

[0036] Step S3, Cooling Stage: When the temperature of the metal-organic framework composite hygroscopic body reaches 60℃~100℃ and is maintained for 2min~10min, the magnetron is turned off, and the carrier gas continues to flow until the metal-organic framework composite hygroscopic body cools down to room temperature, thus completing the regeneration.

[0037] Furthermore, the carrier gas is dry air or nitrogen, with a flow rate of 0.1 L / min to 1.0 L / min. During the desorption stage, the carrier gas continuously flows over the surface of the metal-organic framework composite absorbent, promptly carrying the desorbed water vapor out of the resonant container, breaking the adsorption equilibrium, thereby accelerating the desorption rate and shortening the regeneration time.

[0038] The magnetron operates at a frequency of 2.45GHz±25MHz and has an output power of 100W~2000W.

[0039] Compared with existing technologies, the advantages of this invention are as follows: The metal-organic framework (MOF) composite hygroscopic body of this invention comprises a fiberglass mat matrix, a metal-organic framework material, and a microwave-responsive enhancement layer. The fiberglass mat matrix provides a large internal cavity and specific surface area, enabling in-situ growth of MOF crystals within the pores. This results in high MOF bonding strength and significantly increases the MOF loading (up to 30%~80%). The moisture absorption capacity per unit mass / volume (saturated water absorption capacity of 0.5-1.2 g / g) is significantly higher than that of simple particle filling or coating in existing technologies. Furthermore, the metal-organic framework composite hygroscopic body of this invention exhibits good mechanical stability, retaining more than 90% of its moisture absorption capacity after more than 10,000 adsorption-desorption cycles.

[0040] Meanwhile, it avoids the problems of pulverization and large pressure drop caused by MOF powder compression molding. Gas can flow through the three-dimensional network of glass fibers, greatly reducing mass transfer resistance and helping to improve adsorption efficiency and effect. Furthermore, the microwave-responsive enhancement layer can selectively absorb microwave energy and volumetrically heat the metal-organic framework material, achieving rapid heating of the metal-organic framework material itself, shortening the desorption time to 2-10 minutes. Simultaneously, the glass fiber mat matrix absorbs almost no microwaves, avoiding thermal damage and charring of the glass fiber mat matrix during regeneration. Moreover, the regeneration energy consumption is low, with a desorption temperature of only 60℃-100℃ and a unit energy consumption of 0.5. ~1.5k Water consumption is reduced by 30% to 50% compared to traditional hot air regeneration.

[0041] The metal-organic framework composite hygroscopic body of the present invention has a high moisture absorption capacity. Combined with a moisture absorption system and control method adapted to the metal-organic framework composite hygroscopic body, it achieves rapid, uniform, and low-energy-consumption desorption and regeneration, and has good cycle stability. Attached Figure Description

[0042] Figure 1This is a photograph of the metal-organic framework composite hygroscopic body in Embodiment 1 of the present invention;

[0043] Figure 2 This is a schematic diagram of the moisture absorption system in Embodiment 2 of the present invention;

[0044] Figure 3 This is a schematic diagram of the resonant container in Embodiment 2 of the present invention. Detailed Implementation

[0045] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0046] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Since the embodiments disclosed in this invention can be arranged in different directions, these terms indicating direction are only for illustration and should not be regarded as limitations. For example, "upper" and "lower" are not necessarily limited to directions opposite to or consistent with the direction of gravity. In addition, features defined with "first" and "second" may explicitly or implicitly include one or more of such features.

[0047] Example 1: Metal-Organic Framework Composite Hygroscopic Body

[0048] A metal-organic framework (MOF) composite moisture absorber includes a fiberglass mat matrix, a MOF material, and a microwave-responsive enhancement layer. The MOF material is loaded on the surface and in the internal pores of the fiberglass mat matrix; the microwave-responsive enhancement layer is distributed inside and / or on the surface of the MOF material.

[0049] As described above, the metal-organic framework composite moisture absorber of the present invention includes a glass fiber felt matrix, a metal-organic framework material, and a microwave response enhancement layer. The glass fiber felt matrix can provide a large internal cavity and specific surface area, enabling MOF crystals to grow in situ within the pores, greatly increasing the MOF loading (up to 30%~80%). The moisture absorption per unit mass / volume (saturated water absorption of 0.5-1.2 g / g) is significantly higher than that of simple particle filling or coating in the prior art.

[0050] Meanwhile, it avoids the problems of pulverization and large pressure drop caused by MOF powder compression molding. Gas can flow through the three-dimensional network of glass fibers, greatly reducing mass transfer resistance and helping to improve adsorption efficiency and effect. In addition, the microwave response enhancement layer can selectively absorb microwave energy and volumetrically heat the metal-organic framework material, enabling the metal-organic framework material to heat up rapidly, while the glass fiber mat matrix hardly absorbs microwaves, which can avoid thermal damage and charring of the glass fiber mat matrix during regeneration.

[0051] Furthermore, the porosity of the fiberglass felt matrix is ​​60%~90%, and the fiber diameter is 5μm~20μm. High porosity provides ample internal space for in-situ growth of MOF crystals and water vapor diffusion channels, avoiding insufficient MOF loading due to excessively low porosity. The fiber diameter enables the metal-organic framework composite hygroscopic body of this invention to achieve excellent mechanical stability.

[0052] Furthermore, the loading of the metal-organic framework material is 30% to 80% of the mass of the fiberglass felt matrix. When the loading is less than 30 wt%, the adsorption capacity per unit volume is insufficient, resulting in poor dehumidification efficiency; when it is greater than 80 wt%, the MOF crystals are prone to clogging the pores of the fiberglass felt or peeling off, increasing airflow resistance and reducing mechanical stability.

[0053] Furthermore, the metal-organic framework material is , , , At least one of the above four MOF materials. All four MOF materials possess abundant open metal sites and high specific surface area, enabling them to efficiently capture water molecules at room temperature, making them suitable for the moisture absorption system of this invention. In this embodiment, the MOF material specifically selected is... .

[0054] Furthermore, the microwave response enhancement layer is composed of a microwave response enhancement additive, which is... Nanoparticles and / or ionic liquids, wherein the ionic liquid is selected from at least one of 1-butyl-3-methylimidazolium tetrafluoroborate and 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide. Further, the... The particle size of the nanoparticles ranges from 10 nm to 50 nm.

[0055] Furthermore, in this embodiment, the metal-organic framework composite moisture absorber is prepared through the following steps:

[0056] (1) Pretreatment: The fiberglass mat was dried at 100℃ for 3 hours to remove surface moisture; then it was placed in a plasma treatment device and treated for 5 minutes in an oxygen atmosphere (power 200W, pressure 50Pa) to introduce hydroxyl functional groups onto the surface of the fiberglass; the dimensions of the fiberglass mat used were as follows: It has a porosity of 80% and a fiber diameter of 10μm.

[0057] (2) Seed impregnation: The pretreated glass fiber mat is immersed in a precursor solution containing a metal source, an organic ligand and a microwave response enhancement agent. The solution is ultrasonically treated for 20 minutes to allow the precursor solution to fully wet the internal pores of the glass fiber.

[0058] (3) In-situ synthesis: The impregnated glass fiber mat is placed in a microwave reactor (power 300W) and reacted at 120℃ for 30min, so that the metal-organic framework material grows in situ on the surface and in the internal pores of the glass fiber mat and forms a composite structure containing microwave response enhancer.

[0059] (4) Activation treatment: The synthesized composite material was washed three times with N,N-dimethylformamide, 100 mL each time, and then washed three times with ethanol, 100 mL each time. It was then vacuum dried at 120℃ for 24 h to obtain the desired metal-organic framework composite hygroscopic body.

[0060] The precursor solution was prepared as follows in this embodiment: Weigh 2.33g (10mmol) and 2.10g (10mmol) pyromellitic acid ( Dissolve the compound in a mixture of 50 mL N,N-dimethylformamide (DMF) and 50 mL formic acid, and stir for 30 min until completely dissolved. Add the following to the solution: 0.5 g of nanoparticles (20 nm in diameter) and 5 mL of 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid were ultrasonically dispersed for 15 min.

[0061] The metal-organic framework composite hygroscopic material prepared in this embodiment is as follows: Figure 1 As shown, the metal-organic framework material constitutes 52% of the mass of the fiberglass mat matrix, as determined by weighing. Scanning electron microscopy was used for observation. The crystals are uniformly distributed on the glass fiber surface, with a crystal size of approximately 200 nm to 500 nm. Nitrogen adsorption tests show that the specific surface area of ​​the composite material is 623 m² / g. Under conditions of 25℃ and 80% relative humidity, the saturated water absorption is 0.78 g / g.

[0062] Example 2: Moisture Absorption System

[0063] like Figure 2 and Figure 3 As shown, a moisture absorption system includes a magnetron 3 (operating frequency 2.45 GHz, output power 1000 W), a waveguide assembly 4 (WR340 rectangular waveguide, size 86.36 mm × 43.18 mm), a resonant container 2, and a metal-organic framework composite moisture absorber 1 prepared in Example 1.

[0064] The waveguide assembly 4 is connected between the output end of the magnetron 3 and the resonant container 2, and is used to guide the microwave energy generated by the magnetron 3 into the resonant container 2. Specifically, the resonant container 2 is provided with a feed port 21, through which the waveguide assembly 4 is connected.

[0065] The resonant container 2 is a hollow container with an conductive inner wall, and the metal-organic framework composite absorbent 1 is housed within the inner cavity of the resonant container 2. In this embodiment, the resonant container 2 is made of copper (or other metal materials such as aluminum or stainless steel), and its inner wall is coated with a high-conductivity metal layer.

[0066] The internal cavity dimensions of the resonant container 2 ( It is adapted to microwave wavelength, so that a stable microwave resonant field can be established in the resonant container 2, so that microwave energy is concentrated and coupled to the microwave response enhancement layer (Fe3O4 and / or ionic liquid) in the metal-organic framework composite hygroscopic body 1, so as to achieve selective, volumetric heating rather than relying solely on heat conduction, and avoid overheating and charring of the glass fiber felt matrix.

[0067] The resonant container 2 is provided with a first air inlet 22 that can be opened and closed to allow humid air to enter, and a second air inlet 23 that can be opened and closed to allow dry air to exit. In this way, during the adsorption stage, the first air inlet 22 is open and the second air inlet 23 is closed, and the humid air to be treated enters the resonant container 2 through the first air inlet 22; during the desorption and regeneration stage, the first air inlet 22 is closed and the second air inlet 23 is open, and the dry air is discharged through the second air inlet 23. The adsorption-regeneration cycle is switched by opening and closing the first air inlet 22 and the second air inlet 23.

[0068] Furthermore, the resonant container 2 is equipped with a rotating platform 7 (rotating at 15 rpm, driven by a motor). The metal-organic framework composite hygroscopic body 1 is placed on the rotating platform 7 and can rotate synchronously with the rotating platform 7. The rotating platform 7 drives the metal-organic framework composite hygroscopic body 1 to rotate, so that it periodically sweeps across regions with different field strengths, resulting in more uniform average absorption power, more thorough desorption, and less local charring.

[0069] Furthermore, the resonant container 2 is equipped with a mode stirrer 6, which in this embodiment is specifically a four-bladed metal structure with a rotation speed of 30 rpm. Microwaves will form standing waves inside the resonant container 2, with high field strength at some locations (hot spots) and near zero field strength at others (cold spots). The mode stirrer 6 can agitate the microwave field distribution, reduce standing wave nodes, and improve the uniformity of the microwave field distribution inside the resonant container 2.

[0070] Furthermore, it also includes a carrier gas supply unit 9, used to introduce carrier gas into the resonant container 2 during the regeneration stage. By introducing carrier gas into the resonant container 2, the desorbed water vapor is immediately carried away by the carrier gas, thereby accelerating regeneration and preventing re-adsorption and condensation backflow. Furthermore, the carrier gas is dry air or nitrogen, and the flow rate is [not specified]. During the desorption stage, the carrier gas continuously flows over the surface of the metal-organic framework composite absorbent 1, carrying the desorbed water vapor out of the resonant container 2 in a timely manner, breaking the adsorption equilibrium, thereby accelerating the desorption rate and shortening the regeneration time.

[0071] In this embodiment, as Figure 2 As shown, the resonant container 2 has a square shape. The first air port 22 and the second air port 23 are respectively opened on the resonant container 2. The first air port 22 is controlled to open and close by a first control valve 51, and the second air port 23 is controlled to open and close by a second control valve 52. In addition, a condensate recovery device 8 for collecting condensate water is also included.

[0072] The outlet of the carrier gas supply unit 9 is connected to a carrier gas pipe 102, which is equipped with a third control valve 91 for controlling the on / off state of the carrier gas pipe 102. The recovery end of the condensate recovery device 8 is connected to a recovery pipe 103, which is equipped with a fourth control valve 81 for controlling the on / off state of the recovery pipe 103. The second control valve 52 is a three-way switching valve, with its first port 521 in fluid communication with the second gas port 23, a guide pipe 101 connected to the second port 522, and an exhaust pipe 24 connected to the third port 523. The free ends of the carrier gas pipe 102, the recovery pipe 103, and the guide pipe 101 are connected by a three-way connector 11.

[0073] During the adsorption stage, the first control valve 51 controls the opening of the first air port 22, and the second control valve 52 controls the closing of the second air port 23. Moist air in the space to be dehumidified enters the resonant container 2 through the first air port 22 and flows through the metal-organic framework composite absorbent 1, where the vapor in the moist air is adsorbed. When the metal-organic framework composite absorbent 1 is saturated, the first control valve 51 controls the closing of the first air port 22, and the first port 521 and the third port 523 of the second control valve 52 are connected. Dry air is discharged from the second air port 23 through the exhaust pipe 24 to the space to be dehumidified. After the dry air is exhausted, the first port 52 and the second port 522 of the second control valve 52 are connected, the third control valve 91 controls the connection of the carrier gas pipe 102, and the fourth control valve 81 controls the connection of the recovery pipe 103. The carrier gas supply unit 9 inputs carrier gas into the resonant container 2 through the second air port 23, carrying the desorbed water vapor out of the resonant container 2 and collecting it in the condensation recovery device 8.

[0074] As described above, the inner cavity size of the resonant container 2 in the moisture absorption system of the present invention is adapted to the microwave wavelength, thereby enabling the establishment of a stable microwave resonant field within the resonant container 2. The field distribution is geometrically matched with the metal-organic framework composite moisture absorber 1, which is beneficial for uniform volume excitation.

[0075] Example 3: Control method of moisture absorption system

[0076] The control method for the moisture absorption system as described in Example 2 includes the following steps:

[0077] Step S1, Adsorption stage: Open the first air port 21 and close the second air port 22 to allow humid air (air with a relative humidity of 80%, a temperature of 25°C, and a flow rate of 0.1L / min) to enter the resonant container 2 and flow through the metal-organic framework composite absorbent 1, using the metal-organic framework composite absorbent 1 to adsorb water vapor in the humid air.

[0078] Step S2, Desorption Stage: When the metal-organic framework composite hygroscopic body 1 is saturated with adsorption (after continuous operation for 10 minutes, the humidity in the resonant container 2 rises to 50% of the humidity at the first air port 22, indicating adsorption saturation), the first air port 21 is closed and the second air port 22 is opened. Dry air is discharged from the second air port 22. Then, carrier gas (N2, flow rate 0.3L / min, 3min) is introduced into the resonant container 2 through the second air port 2. The magnetron 3 (power 800W, continuous wave mode) is activated, and microwaves pass through the resonant container 2 to act on the metal-organic framework composite hygroscopic body 1, causing the adsorbed water molecules to vaporize and desorb.

[0079] Step S3, Cooling Stage: When the temperature of the metal-organic framework composite hygroscopic body 1 reaches 80℃ (by adjusting the power of the magnetron 3 to maintain the temperature at 80±5℃) and is maintained for 2 minutes, the magnetron 3 is turned off, and the carrier gas continues to flow until the metal-organic framework composite hygroscopic body 1 cools down to room temperature, thus completing the regeneration.

[0080] Loop testing:

[0081] The adsorption-desorption cycle (steps S1-S2-S3) was repeated 50 times. The saturated water absorption in the 50th cycle was 0.72 g / g, which was 92.3% of the water absorption in the first cycle (0.78 g / g), showing good cycle stability.

[0082] Comparative Example

[0083] To verify the technical effect of the present invention, the following comparative examples were set up, and the results are shown in Table 1:

[0084] Comparative Example 1: Pure glass fiber felt (without MOF loading) was used as the absorbent. The gravimetric characterization results showed that the saturated water absorption was only 0.05 g / g, which was much lower than that of Example 1 (0.78 g / g).

[0085] Comparative Example 2: Pure fiberglass felt (loaded only with MOF, without microwave response enhancement layer) was used as the absorbent, and the rest was the same as in Example 3. The results showed that an output power of 1300W was required to achieve the same desorption effect as in Example 1.

[0086] Comparative Example 3: The metal-organic framework composite hygroscopic body of Example 1 was used, but the mode stirrer and rotating platform were not installed in the resonant container; otherwise, it was the same as Example 3. The results showed that the internal temperature difference of the metal-organic framework composite hygroscopic body reached 25°C, and the local temperature exceeded 120°C. The MOF structure partially collapsed, and the hygroscopic capacity decreased to 65% of the initial value after 50 cycles.

[0087] Comparative Example 4: Traditional hot air regeneration (120℃ hot air, regeneration time 30 min) was used, with the rest being the same as in Example 3. The results showed that the unit regeneration energy consumption was 4.3 kWh / kg water, which was 4.5 times that of Example 3 (0.95 kWh / kg water).

[0088] The above test results show that the metal-organic framework composite hygroscopic body of the present invention has a high moisture absorption capacity. Combined with the moisture absorption system and control method, it achieves rapid, uniform, and low-energy desorption and regeneration, and has good cycle stability.

[0089] Table 1. Performance test results of Examples 1, 3, and comparative examples.

[0090]

[0091] In another embodiment, the moisture absorption system of the present invention can be controlled by a voice module, which is equipped with a controller, a voice receiving module, and a voice parsing module. The voice receiving module receives user commands, and the voice parsing module parses the commands. Based on the parsed commands, the controller controls the moisture absorption system to perform corresponding operations, thereby realizing intelligent regulation of the moisture absorption system and improving the user experience.

[0092] The term "fluid connectivity" as used in this invention refers to the spatial relationship between two components or parts (hereinafter referred to as the first part and the second part, respectively), that is, a fluid (gas, liquid, or a mixture of both) can flow from the first part along a flow path and / or be transported to the second part. This can be a direct connection between the first part and the second part, or an indirect connection between the first part and the second part through at least one third party. This third party can be a fluid channel such as a pipe, channel, conduit, guide, hole, or groove, or a chamber that allows fluid to flow through, or a combination of the above.

Claims

1. A metal-organic framework composite moisture absorber, characterized in that, include: Fiberglass mat matrix; Metal-organic framework material is loaded onto the surface and internal pores of the fiberglass felt matrix; A microwave response enhancement layer is distributed within and / or on the surface of the metal-organic framework material.

2. The metal-organic framework composite moisture absorber as described in claim 1, characterized in that, The porosity of the fiberglass felt matrix is ​​60%~90%, and the fiber diameter is 5μm~20μm.

3. The metal-organic framework composite moisture absorber as described in claim 1, characterized in that, The loading of the metal-organic framework material is 30% to 80% of the mass of the fiberglass felt matrix.

4. The metal-organic framework composite moisture absorber as described in claim 1, characterized in that, The metal-organic framework material is , , , At least one of them.

5. The metal-organic framework composite moisture absorber as described in claim 1, characterized in that, The microwave response enhancement layer is composed of a microwave response enhancement additive, which is... Nanoparticles and / or ionic liquids, wherein the ionic liquid is selected from at least one of 1-butyl-3-methylimidazolium tetrafluoroborate and 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide.

6. The metal-organic framework composite moisture absorber as described in claim 5, characterized in that, The The particle size of the nanoparticles ranges from 10 nm to 50 nm.

7. The metal-organic framework composite hygroscopic material according to any one of claims 1 to 6, characterized in that, Prepared by the following steps: (1) Pretreatment: Dry the glass fiber mat at 80℃~120℃ for 2h~4h, then place it in a plasma treatment device and treat it in an oxygen atmosphere for 3min~10min to introduce hydroxyl functional groups on the surface of the glass fiber. (2) Seed impregnation: The pretreated glass fiber mat is immersed in a precursor solution containing a metal source, an organic ligand and a microwave response enhancement agent, and ultrasonically treated for 10 min to 30 min. (3) In-situ synthesis: The impregnated glass fiber mat is placed in a microwave reactor and reacted at 100℃~150℃ for 15min~60min; (4) Activation treatment: The synthesized composite material is washed with organic solvent and vacuum dried at 80℃~130℃ for 12h~24h to obtain the desired metal-organic framework composite hygroscopic body.

8. The metal-organic framework composite moisture absorber as described in claim 7, characterized in that, The precursor solution comprises: 1mmol / L~15mmol / L 1mmol / L~15mmol / L The nanoparticles are 0.1wt%~1wt%, the ionic liquid is 1wt%~10wt%, and the solvent is a mixture of N,N-dimethylformamide and formic acid.

9. A moisture absorption system, characterized in that, Including magnetrons, waveguide components, resonant containers, and metal-organic framework composite moisture absorbers as described in any one of claims 1 to 8; The waveguide assembly is connected between the output end of the magnetron and the resonant container to guide the microwave energy generated by the magnetron into the resonant container; the resonant container is a hollow metal container with conductive inner walls, and the metal-organic framework composite hygroscopic body is housed in the inner cavity of the resonant container. Furthermore, the internal cavity size of the resonant container is adapted to the microwave wavelength to form a microwave resonant field in the internal cavity, and the resonant container is respectively provided with a first air port that can be opened and closed to allow humid air to enter and a second air port that can be opened and closed to allow dry air to exit.

10. The moisture absorption system as described in claim 9, characterized in that, The resonant container is provided with a rotating platform, and the metal-organic framework composite hygroscopic body is placed on the rotating platform and can rotate synchronously with the rotating platform.

11. The moisture absorption system as described in claim 9, characterized in that, The resonant container is equipped with a mode stirrer.

12. The moisture absorption system as described in claim 9, characterized in that, It also includes a carrier gas supply unit for introducing carrier gas into the resonant container during the regeneration phase.

13. A control method for a moisture absorption system as described in any one of claims 9 to 12, characterized in that, Includes the following steps: Step S1, Adsorption stage: Open the first air port and close the second air port to allow humid air to enter the resonant container and flow through the metal-organic framework composite moisture absorber; Step S2, Desorption Stage: When the metal-organic framework composite hygroscopic body is saturated with adsorption, the first air port is closed and the second air port is opened. Dry air is discharged from the second air port, and then carrier gas is introduced into the resonant container through the second air port. The magnetron is activated, and microwaves act on the metal-organic framework composite hygroscopic body through the resonant container, causing the adsorbed water molecules to vaporize and desorb. Step S3, Cooling Stage: When the temperature of the metal-organic framework composite hygroscopic body reaches 60℃~100℃ and is maintained for 2min~10min, the magnetron is turned off, and the carrier gas continues to flow until the metal-organic framework composite hygroscopic body cools down to room temperature, thus completing the regeneration.

14. The control method for the moisture absorption system as described in claim 13, characterized in that, The carrier gas is dry air or nitrogen, and the flow rate is 0.1 L / min to 1.0 L / min.

15. The control method for the moisture absorption system as described in claim 13, characterized in that, The magnetron operates at a frequency of 2.45GHz±25MHz and has an output power of 100W~2000W.

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