Metal organic framework material-based dehumidification rotary wheel, preparation method and dehumidifier

Abstract

The application provides a metal organic framework material-based dehumidification runner, a preparation method and a dehumidifier, and relates to the technical field of air dehumidification. The dehumidification runner comprises a base material and a MOF adsorption layer loaded on the base material; in the MOF adsorption layer, the loading amount of MOF is 30 kg / m3 to 150 kg / m3 in terms of the total volume of the runner, and the primary particle size of MOF particles is 0.1 to 5 microns; and the MOF adsorption layer is formed by coating slurry with a viscosity of 100 to 2000 cps. The dehumidification runner of the application can stably achieve a dew point of less than or equal to -10 DEG C under low-temperature regeneration conditions of less than or equal to 70 DEG C, and has excellent mechanical strength and long service life.

Description

Technical Field

[0001] This invention relates to the field of air dehumidification technology, specifically to a dehumidification impeller based on metal-organic framework material, its preparation method, and a dehumidifier. Background Technology

[0002] Dehumidifying rotors are core equipment in the field of industrial air drying, widely used in applications with stringent humidity requirements such as lithium battery manufacturing, food and pharmaceuticals, and aerospace. Traditional silica gel rotors and molecular sieve rotors suffer from high regeneration temperatures (typically 100℃-140℃) and high energy consumption, and are difficult to achieve dew points of -10℃ or lower under low-temperature regeneration conditions.

[0003] Metal-organic frameworks (MOFs) are considered to have enormous application potential in adsorption dehumidification due to their unique structural properties. Theoretically, thanks to their tunable pore structure and excellent adsorption performance, MOF materials are expected to simultaneously achieve low dew point dehumidification and low-temperature regeneration—that is, using industrial waste heat (≤70℃) to drive regeneration while obtaining air with a dew point below -10℃. However, the current technological status quo is that these theoretical advantages have not yet been synergistically realized in practical MOF dehumidification rotor products. Existing research and reports on MOF-based dehumidification rotors either focus on low-temperature regeneration (e.g., 50-70℃ regeneration) but fail to achieve an industrial-grade dew point of -10℃, or require increasing the regeneration temperature to achieve deep dehumidification, and generally suffer from the fatal flaw of insufficient long-term operational life.

[0004] When attempting to fabricate dehumidifying rotors from MOF materials, those skilled in the art face a series of deep-rooted technical biases and cognitive misconceptions, which are mainly reflected in the neglect of the essential differences between MOFs and traditional inorganic materials such as silica gel and molecular sieves.

[0005] The intrinsic differences between MOFs and traditional inorganic adsorbent materials. Silica gel and molecular sieves are inorganic materials, inherently resistant to high temperatures. Their rotors can be sintered at high temperatures after coating and drying, completely removing the organic binders introduced during preparation and ensuring pore permeability. However, MOFs, as organic-inorganic hybrid materials, have a clear upper limit to their temperature resistance and cannot withstand high-temperature sintering. If a purely inorganic binder (such as silica sol or alumina sol) is used, the insufficient affinity between MOFs and inorganic binders requires a large amount to ensure adhesion, which severely reduces the effective proportion of MOFs. To reduce the amount of inorganic binder and increase the proportion of MOFs, a small amount of organic binder must be introduced. However, organic binders are flexible and can coat the MOF pores, causing a series of problems such as decreased adsorption capacity, insufficient adsorption depth, and impaired mass and heat transfer. Therefore, the preparation of MOF rotors must find a stringent balance between the binder system, dosage, and MOF performance—a challenge never encountered in the preparation of silica gel and molecular sieve rotors.

[0006] Furthermore, the mass and heat transfer characteristics of MOFs differ significantly from those of silica gel and molecular sieves. MOFs possess ultra-high porosity (specific surface area up to 6000 m² / g) and contain organic ligands, which hinders phonon transport and results in a thermal conductivity far lower than that of inorganic materials such as silica gel. Simultaneously, MOFs are predominantly microporous (<2 nm), while silica gel is predominantly mesoporous. This structural difference means that, under the same coating thickness and loading, the mass and heat transfer resistance of the MOF adsorption layer is greater, the diffusion path of water molecules during adsorption and desorption is longer, and internal heat transfer is slower. Therefore, simply applying the rotor preparation process developed for silica gel and molecular sieves will inevitably lead to the inability of MOF rotors to achieve deep desorption under low-temperature regeneration conditions, thus failing to reach the target dew point.

[0007] The fundamental difference lies in the viscosity window of the slurry. In the preparation of traditional silica gel and molecular sieve rotors, the viscosity of the coating slurry is usually no more than 50 cps because the inorganic materials themselves have good affinity with inorganic binders, and organic impurities can be removed by high-temperature sintering. However, the preparation of MOF rotors faces completely different technical constraints: in low-viscosity slurries (≤50 cps), the settling velocity of MOF particles is too fast, resulting in excessive bulk density and uneven coating during coating, and the target loading cannot be achieved in a single coating; if multiple coatings are used, it will lead to complex processes, poor adhesion between coatings, and increased powder shedding rate. The inventors have found that the viscosity of MOF slurry must be increased to the specific range of 100-2000 cps in order to achieve the target loading of 30-150 kg / m³ in a single coating while ensuring coating uniformity, and at the same time ensuring that the adhesion between the coating and the substrate meets the requirements for long-term service life. This high-viscosity process window is fundamentally different from the conventional process (≤50 cps) for silica gel and molecular sieve rotors, and cannot be easily deduced by those skilled in the art.

[0008] The synergistic mechanism of particle size, viscosity, and settling velocity. There is a precise synergistic relationship between MOF particle size, slurry viscosity, and particle settling velocity: if the particle size is too small or the viscosity is too high, the settling velocity is too slow, and the particles cannot form a dense packing during the coating and drying process, resulting in low packing density and insufficient loading; if the particle size is too large or the viscosity is too low, the settling velocity is too fast, and the particles settle rapidly at the drying front of the coating liquid, resulting in excessive packing density, blockage of mass transfer channels within the coating, and a sharp increase in resistance to water molecule diffusion. Only when particle size, viscosity, and settling velocity are precisely matched can a MOF adsorption layer with both high loading capacity and excellent mass transfer performance be formed, thereby achieving a dew point ≤-10℃ under low-temperature regeneration conditions of 70℃.

[0009] Regarding particle size, there is a dual technical bias in this field, a "too much of a good thing" attitude. On the one hand, it is generally believed that larger MOF crystals are more perfect and have a higher specific surface area, thus exhibiting stronger adsorption performance. However, our research has found that large-particle MOFs have excessively long mass transfer paths in the rotor, increasing the resistance to water molecule diffusion and preventing deep desorption under 70°C low-temperature regeneration conditions. On the other hand, some argue that smaller particle sizes result in higher specific surface areas and better adsorption performance. However, we have found that excessively small particle sizes (e.g., nanoscale) lead to an excessive number of crystal defect sites. Although the specific surface area is high, the structural stability is poor, making it prone to structural collapse during repeated adsorption and desorption processes, resulting in a sharp decrease in cycle life. For example, we conducted a comparative experiment using 66 nm MOF-801 reported in the literature "Enhanced atmospheric water harvesting efficiency through green-synthesized MOF-801: a comparative study with solvothermal synthesis." We found that after being loaded onto the rotor, it exhibited extremely poor cycle life and could not reach a dew point of -10°C under 70°C regeneration conditions. This directly proves that there is an optimal window for particle size; it is neither better to be as large as possible nor as small as possible.

[0010] The decisive influence of coating process and roller forming sequence. In existing technologies, such as patent application CN202411205936A, a "form-then-coat" process route is used. This involves first forming a honeycomb preform of the substrate, then dipping it in MOF slurry. It explicitly states that "multiple dip coatings" are required to achieve the desired load capacity. However, a single dip coating cannot achieve the desired effect because a single dip requires a sufficiently high solids content in the slurry to reach the required load capacity. Excessive solids content often results in high slurry viscosity, which can clog the roller's pores during coating, preventing humid gas from efficiently passing through the roller holes. Our research has revealed a fundamental flaw in this process route: the complex internal flow channels of the formed honeycomb preform lead to uneven distribution of the MOF slurry during dipping. After drying, the coating tends to accumulate at the edges and corners, causing stress concentration on the flow channel walls, resulting in a significantly increased powder shedding rate. Furthermore, multiple dip coatings lead to poor adhesion between coatings, further exacerbating performance degradation. More importantly, the inventors attempted to use the "bare rotor immersion method" (i.e., directly immersing the honeycomb rotor skeleton into the MOF slurry). No matter how the slurry formula, number of immersions, and drying conditions were adjusted, it was impossible to simultaneously achieve a dew point of ≤-10℃ and a long service life. The fundamental reason is that the formed rotor cannot form sufficient mechanical anchoring between the MOF coating and the substrate, and the coating thickness cannot be precisely controlled, resulting in uncontrollable mass and heat transfer performance and a large number of rotor honeycomb pore blockage phenomena.

[0011] In summary, overcoming the aforementioned technical biases, correctly understanding the intrinsic properties of MOFs and their essential differences from silica gel and molecular sieves, revealing the synergistic mechanism between particle size, slurry viscosity, settling velocity, and loading, selecting the correct process sequence (coating before winding rather than impregnation), transforming the theoretical advantages of MOF materials into practical product advantages, and developing a MOF dehumidification rotor that can stably achieve a dew point of ≤-10℃ under low-temperature regeneration conditions of ≤70℃, and possesses excellent mechanical strength and long service life, remains a pressing technical challenge in this field. Summary of the Invention

[0012] This invention aims to solve the technical problems of existing MOF dehumidification rotors, such as the difficulty in simultaneously achieving low-temperature regeneration and low dew point, and the short lifespan caused by easy MOF coating peeling. Therefore, it provides a dehumidification rotor based on metal-organic framework materials, its preparation method, and a dehumidifier. This invention first forms a uniform MOF coating on a planar substrate through a single coating process, followed by drying, pressing, and winding. This process sequence allows the MOF adsorption layer to form in situ on the substrate and further bond tightly with the substrate fibers during subsequent pressing, forming a mechanically interlocked structure. The coating adhesion is far superior to that of the dip coating method. Simultaneously, the load can be precisely controlled with a single coating, avoiding the complexity and performance instability of multiple dip coating processes.

[0013] This invention first provides a dehumidification rotor based on a metal-organic framework material. The dehumidification rotor includes a substrate and a MOF adsorption layer loaded on the substrate. In the MOF adsorption layer, the MOF loading is 30 kg / m³ to 150 kg / m³ based on the total volume of the rotor, and the primary particle size of the MOF particles is 0.1 μm to 5 μm. The MOF adsorption layer is formed by a coating slurry with a viscosity of 100 cps to 2000 cps.

[0014] Preferably, the dehumidifying impeller operates at a regeneration temperature ≤70℃, and its outlet dew point after dehumidifying the air is ≤-10℃.

[0015] Preferably, the MOF is an aluminum-based, iron-based, zirconium-based, or chromium-based metal-organic framework material with a specific surface area of ​​500-4000 m² / g.

[0016] Preferably, the MOF is selected from MIL-101(Cr), MIL-101(Fe), MIL-100(Fe), MIL-100(Al), MIL-53(Al), MIL-53(Cr), UiO-66(Zr), UiO-66-NH2(Zr), MOF-801(Zr), MOF-808(Zr), CAU-1(Al), CAU-10(Al), NU-1000(Zr), Al-fumarate, MIL-96(Al), MIL-120(Al), MIL-160(Al), Cr-soc-MOF-1, MOF-303(Al) or MOF-841(Zr).

[0017] Preferably, the substrate is glass fiber cloth.

[0018] This invention also provides a method for preparing a dehumidifying rotor based on a metal-organic framework material, comprising the following steps: Step 1: Coating and Molding A coating slurry is applied to a planar substrate in one step, and after drying, a MOF-substrate composite sheet with a MOF adsorption layer is formed; the viscosity of the coating slurry is 100 cps to 2000 cps. Step 2: Pressing and Shaping The MOF-substrate composite sheet obtained in step one is pressed into a corrugated shape; Step 3: Composite Molding The corrugated composite sheet obtained in step two is combined with the MOF-substrate composite sheet obtained in step one to form a dehumidifying rotor based on metal-organic framework material.

[0019] Preferably, the coating slurry is made by mixing MOF particles, binder and solvent.

[0020] Preferably, the adhesive is selected from one or more of silica sol, alumina sol, and water-based organic adhesives.

[0021] Preferably, the amount of binder added is 3% to 50% of the mass of the MOF particles.

[0022] A dehumidifier includes the aforementioned dehumidifying impeller based on a metal-organic framework material.

[0023] Compared with the prior art, the present invention has the following beneficial effects: 1. Achieved synergy between low-temperature regeneration and low dew point: This invention is the first to transform the theoretical advantages of MOF materials into a practical product breakthrough, realizing that the dehumidification impeller based on MOF can stably output air with a dew point of ≤-10℃ at a regeneration temperature of ≤70℃.

[0024] 2. This invention reveals the synergistic mechanism of particle size, viscosity, and settling velocity, breaking multiple technical biases: For the first time, this invention systematically reveals the synergistic relationship between MOF particle size, slurry viscosity, and particle settling velocity, proving that only when the three are precisely matched (primary particle size 0.1-5 μm, viscosity 100-2000 cps) can an adsorption layer with both high loading capacity and excellent mass transfer performance be formed. Simultaneously, comparative experiments demonstrate that neither excessively large (14 μm) nor excessively small (66 nm) particle sizes can achieve the target performance, breaking the dual technical biases of "larger particle size is better" and "smaller particle size is better."

[0025] 3. A unique slurry process window was established for MOFs, distinct from silica / molecular sieves: This invention reveals that MOF rotors require a slurry viscosity of 100-2000 cps to achieve the target loading capacity and ensure long-term lifespan in a single coating operation, while traditional silica / molecular sieve rotors only require a slurry viscosity of ≤50 cps. This fundamental difference proves that the preparation process of MOF rotors is not a simple application of existing technologies, but rather requires a completely new process design.

[0026] 4. This invention demonstrates the irreplaceable nature of the "coating before winding" process: Through comparative experiments, this invention proves that regardless of parameter adjustments, it is impossible to simultaneously achieve low dew point and long lifespan using the "bare roller dipping method" or the "forming before coating" process (such as CN202411205936A). Only the process sequence of this invention can ensure sufficient mechanical anchoring between the MOF coating and the substrate, guaranteeing the controllability of coating adhesion, uniformity, and mass and heat transfer performance.

[0027] 5. Achieving the target load with a single coating, and a simple process: Existing technologies (such as CN202411205936A) clearly state that "multiple dip coatings" are required to achieve the desired load, resulting in complex processes and poor consistency. This invention achieves a load of 30-150 kg / m³ with only one coating, a short process flow, strong controllability, and suitability for large-scale industrial production.

[0028] 6. Breaking the technical prejudice that "the higher the coating amount, the better": This invention has screened out the optimal loading window of 30 kg / m³ to 150 kg / m³ through a large number of experiments. Within this range, the best balance between adsorption capacity and mass and heat transfer performance can be achieved.

[0029] 7. Overcoming the technical challenge of incompatibility between MOF and binder system: This invention recognizes the inherent limitations of MOF's poor affinity with inorganic binders and its inability to remove organic matter through high-temperature sintering. By precisely controlling the slurry viscosity and the one-time coating process, the permeability of MOF channels is preserved to the maximum extent while ensuring coating adhesion, thus avoiding problems such as binder clogging and coating peeling.

[0030] 8. Excellent mechanical strength and long-term stability: The process used in this invention allows the MOF adsorption layer to be formed in situ on the substrate and to be further tightly bonded to the substrate fibers during the subsequent pressing process, effectively solving the industry pain point of insufficient long-term life of MOF rollers. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of the dehumidifying rotor core prepared in Embodiment 1 of the present invention.

[0032] Figure 2 This is a scene diagram of the workshop coating and pressing of the dehumidifying rotor core prepared in Example 1 of the present invention.

[0033] Figure 3 This is a physical image of the dehumidifying rotor core prepared in Example 1 of the present invention.

[0034] Figure 4 This is a physical image of the dehumidifying rotor core prepared in Embodiment 2 of the present invention.

[0035] Figure 5 This is a physical image of the dehumidifying rotor core prepared in Example 3 of the present invention.

[0036] Figure 6 This is a physical image of the dehumidifying rotor core prepared in Example 4 of the present invention.

[0037] Figure 7 This is a physical image of the dehumidifying rotor core prepared in Comparative Example 5 of the present invention.

[0038] Figure 8 This is a SEM image of the dehumidifying rotor core prepared in Example 1 of the present invention.

[0039] Figure 9 This is a comparison chart of the cycle lifetime of Example 1 and Comparative Example 2 (66 nm MOF) of the present invention.

[0040] Figure 10 This is a comparison chart of the cycle life of Example 1 and Comparative Example 5 (bare wheel immersion) of the present invention.

[0041] Figure 11 This is a comparison chart of the cycle life of Example 1 of the present invention with Comparative Examples 6 and 7 (molecular sieve and silica gel using MOF coating process). Detailed Implementation

[0042] This invention first provides a dehumidifying rotor based on a metal-organic framework material. The dehumidifying rotor includes a substrate and a MOF adsorption layer loaded on the substrate. In the MOF adsorption layer, the MOF loading, based on the total volume of the rotor, is 30 kg / m³ to 150 kg / m³, preferably 40 kg / m³ to 120 kg / m³, more preferably 50 kg / m³ to 100 kg / m³. The primary particle size of the MOF particles is 0.1 μm to 5 μm, preferably 0.3 μm to 4 μm, more preferably 0.4 μm to 3 μm. The MOF adsorption layer is formed from a coating slurry with a viscosity of 100 cps to 2000 cps.

[0043] According to the present invention, the dehumidifying impeller operates at a regeneration temperature ≤70℃, and its outlet dew point after dehumidifying the air is ≤-10℃.

[0044] According to the present invention, the MOF is preferably an aluminum-based, iron-based, zirconium-based, or chromium-based metal-organic framework material with a specific surface area of ​​500-4000 m² / g, and more preferably selected from MIL-101(Cr), MIL-101(Fe), MIL-100(Fe), MIL-100(Al), MIL-53(Al), MIL-53(Cr), UiO-66(Zr), UiO-66-NH2(Zr), MOF-801(Zr), MOF-808(Zr), CAU-1(Al), CAU-10(Al), NU-1000(Zr), Al-fumarate, MIL-96(Al), MIL-120(Al), MIL-160(Al), Cr-soc-MOF-1, MOF-303(Al), or MOF-841(Zr).

[0045] According to the present invention, the substrate is preferably glass fiber cloth.

[0046] This invention also provides a method for preparing a dehumidifying rotor based on a metal-organic framework material, comprising the following steps: Step 1: Coating and Molding A coating slurry is applied to a planar substrate in a single pass, and after drying, a MOF-substrate composite sheet with a MOF adsorption layer is formed. The viscosity of the coating slurry is 100 cps to 2000 cps, preferably 200 cps to 1200 cps, and more preferably 200 cps to 1000 cps. The coating slurry is prepared by mixing MOF particles, a binder, and a solvent. The binder is preferably selected from one or more of silica sol, alumina sol, and water-based organic binders. The amount of binder added is preferably 3% to 50% of the mass of the MOF particles. The dry weight of the MOF on the substrate after coating corresponds to a load of 30 kg / m³ to 150 kg / m³ on the total volume of the roller. The planar substrate is preferably glass fiber cloth.

[0047] Step 2: Pressing and Shaping The MOF-substrate composite sheet obtained in step one is pressed into a corrugated shape; the height of the corrugation is preferably 1.2-2.4 mm; Step 3: Composite Molding The corrugated composite sheet obtained in step two and the MOF-substrate composite sheet obtained in step one are preferably combined into a dehumidifying rotor core by alternating stacking and winding or bonding. The rotor core is honeycomb-shaped, thus obtaining a dehumidifying rotor based on metal-organic framework material.

[0048] A dehumidifier includes the aforementioned dehumidifying impeller based on a metal-organic framework material.

[0049] The above-mentioned dehumidifying impeller was tested using the following specific testing method: Powder shedding rate test: The rotor sample was placed in an airflow with a wind speed of 2 m / s and continuously blown for 30 minutes. The weight difference before and after the test was the percentage of the initial MOF load.

[0050] Outlet dew point test: Under standard test conditions (inlet temperature 25℃, relative humidity 60%, processing air velocity 2 m / s, regeneration temperature 70℃, regeneration air velocity 0.5 m / s), the outlet air dew point is continuously monitored using a dew point meter.

[0051] MOF primary particle size test: The morphology of MOF particles was observed using a scanning electron microscope (SEM), and the primary particle size (non-aggregate particle size) of at least 100 particles was counted, and the volume average particle size was taken.

[0052] Slurry viscosity test: The viscosity was tested at 25°C using a rotational viscometer.

[0053] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with embodiments. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0054] Example 1 1. Material preparation: MOF material: MOF-801 type MOF (Zr-based) was selected, with a primary particle size of 1 μm (SEM observation) and a specific surface area of ​​approximately 800 m² / g.

[0055] Substrate: Alkali-free fiberglass cloth.

[0056] Adhesive: A mixture of silica sol (SiO2 content 30%) and water-based acrylic adhesive in a mass ratio of 8:2.

[0057] Solvent: Deionized water.

[0058] 2. Preparation process: Step 1: Mix 100 parts by weight of MOF-801, 20 parts by weight of binder (total), and 100 parts by weight of deionized water to prepare a coating slurry. The viscosity of the slurry is tested to be 800 cps. Apply the coating slurry evenly onto the fiberglass cloth in one pass using a scraping method. Control the coating thickness so that the dry weight of MOF corresponds to a load of approximately 100 kg / m³ on the roller volume. Obtain the MOF-fiberglass cloth composite sheet.

[0059] Step 2: Press the composite sheet obtained in Step 1 into a corrugated shape using a corrugated roller, with a corrugation height of 1.8 mm.

[0060] Step 3: Alternately stack the corrugated sheet obtained in Step 2 with the MOF-fiberglass composite sheet, roll them into a cylindrical shape, and fix them with a high-temperature resistant adhesive (epoxy resin glue or silicone-epoxy hybrid glue) to form a honeycomb-shaped rotor core, thus obtaining a dehumidifying rotor.

[0061] The rotor prepared in Example 1 was tested according to the above testing method, and the results are shown in Table 1. A schematic diagram of the prepared rotor core is shown below. Figure 1 As shown in the diagram, the workshop coating and pressing process is as follows: Figure 2 As shown in the picture, the actual product is as follows. Figure 3 As shown, the SEM image is as follows: Figure 8 As shown.

[0062] Example 2 The steps and conditions were the same as in Example 1, except that: UiO-66 type MOF (Zr-based) was used, with a primary particle size of 1 μm and a specific surface area of ​​approximately 1000 m² / g; the slurry viscosity was adjusted to 500 cps; and the target loading was adjusted to 80 kg / m³. Test results are shown in Table 1. A photograph of the actual product is shown below. Figure 4 As shown.

[0063] Example 3 The steps and conditions were the same as in Example 1, except that: MIL-101(Cr) type MOF was used, with a primary particle size of 4 μm (SEM observation) and a specific surface area of ​​approximately 2500 m² / g; aluminum sol was used as the binder; the slurry viscosity was adjusted to 1500 cps; and the target loading was adjusted to 120 kg / m³. Test results are shown in Table 1. A photograph of the actual product is shown below. Figure 5 As shown.

[0064] Example 4 The steps and conditions were the same as in Example 1, except that: MIL-100(Fe) type MOF (Fe-based) was used, with a primary particle size of 0.5 μm and a specific surface area of ​​approximately 1800 m² / g; a water-based acrylic binder was used; the slurry viscosity was adjusted to 300 cps; and the target loading was adjusted to 50 kg / m³. Test results are shown in Table 1. A photograph of the actual product is shown below. Figure 6 As shown.

[0065] Example 5 The steps and conditions were the same as in Example 1, except that: MIL-53(Al) type MOF (Al-based) was used, with a primary particle size of 3 μm and a specific surface area of ​​approximately 1000 m² / g; the binder was a mixture of silica sol and alumina sol (mass ratio 5:5); the slurry viscosity was adjusted to 1000 cps; and the target loading was adjusted to 120 kg / m³. The test results are shown in Table 1.

[0066] Example 6 The steps and conditions were the same as in Example 1, except that: MIL-101(Cr) type MOF (Cr-based) was used, with a primary particle size of 1.5 μm and a specific surface area of ​​approximately 2900 m² / g; a water-based polyurethane binder was used; the slurry viscosity was adjusted to 1200 cps; and the target loading was adjusted to 150 kg / m³. The test results are shown in Table 1.

[0067] Example 7 The steps and conditions were the same as in Example 1, except that: UiO-66-NH2 type MOF (Zr-based) was used, with a primary particle size of 1.5 μm and a specific surface area of ​​approximately 1300 m² / g; the slurry viscosity was adjusted to 600 cps; and the target loading was adjusted to 90 kg / m³. The test results are shown in Table 1.

[0068] Example 8 The steps and conditions were the same as in Example 1, except that: MIL-101(Fe) type MOF (Fe-based) was used, with a primary particle size of 0.3 μm and a specific surface area of ​​approximately 2200 m² / g; the binder was a mixture of silica sol and water-based acrylate (mass ratio 6:4); the slurry viscosity was adjusted to 400 cps; and the target loading was adjusted to 60 kg / m³. The test results are shown in Table 1.

[0069] Example 9 The steps and conditions were the same as in Example 1, except that: MOF-303 type MOF (Al-based) was used, with a primary particle size of 3.5 μm and a specific surface area of ​​approximately 1200 m² / g; the slurry viscosity was adjusted to 1200 cps; and the target loading was adjusted to 110 kg / m³. The test results are shown in Table 1.

[0070] Example 10 The steps and conditions were the same as in Example 1, except that: MOF-808 type MOF (Zr-based) was used, with a primary particle size of 0.2 μm and a specific surface area of ​​approximately 1300 m² / g; the slurry viscosity was adjusted to 1300 cps; and the target loading was adjusted to 50 kg / m³. The test results are shown in Table 1.

[0071] Example 11 The steps and conditions were the same as in Example 1, except that: CAU-10 type MOF (Al-based) was used, with a primary particle size of 1.2 μm and a specific surface area of ​​approximately 700 m² / g; the slurry viscosity was adjusted to 600 cps; and the target loading was adjusted to 90 kg / m³. The test results are shown in Table 1.

[0072] Example 12 The steps and conditions were the same as in Example 1, except that: Al-fumarate type MOF (Al-based) was selected, with a primary particle size of 1.8 μm and a specific surface area of ​​approximately 500 m² / g; the slurry viscosity was adjusted to 800 cps; and the target loading was adjusted to 80 kg / m³. The test results are shown in Table 1.

[0073] Example 13 The steps and conditions were the same as in Example 1, except that: MIL-160-(Al) type MOF (Al-based) was selected, with a primary particle size of 2.2 μm and a specific surface area of ​​approximately 1000 m² / g; the slurry viscosity was adjusted to 700 cps; and the target loading was adjusted to 120 kg / m³. The test results are shown in Table 1.

[0074] Example 14 The steps and conditions were the same as in Example 1, except that: Cr-soc-MOF-1 type MOF (Cr-based) was selected, with a primary particle size of 1 μm and a specific surface area of ​​approximately 1600 m² / g; the slurry viscosity was adjusted to 400 cps; and the target loading was adjusted to 110 kg / m³. The test results are shown in Table 1.

[0075] Comparative Example 1 (14μm large particle size MOF) The same MOF-801 type MOF (Zr-based) material and process as in Example 1 were used, the only difference being that large-particle-size MOF-801 was selected, with a primary particle size of 14 μm. All other conditions were exactly the same as in Example 1. The test results are shown in Table 1.

[0076] Comparative Example 2 (Nanoscale MOF) The same materials and processes as in Example 1 were used, with the only difference being the selection of MOF-801 nanoparticles obtained through a green synthesis method. The primary particle size of these nanoparticles was 66 nm (observed by SEM, see "Enhanced atmospheric water harvesting efficiency through green-synthesized MOF-801: a comparative study with solvothermal synthesis"). All other conditions were identical to those in Example 1. The test results are shown in Table 1. A comparison of the cycle life of Example 1 and Comparative Example 2 (66 nm MOF) is shown in the figure below. Figure 9 As shown.

[0077] Comparative Example 3 Using the same materials and processes as in Example 1, but through multiple coatings (2 times), the MOF loading of the final rotor reached as high as 200 kg / m³. The test results are shown in Table 1.

[0078] Comparative Example 4 The same materials and processes as in Example 1 were used, but the coating amount was controlled so that the MOF load on the final rotor was only 20 kg / m³. The test results are shown in Table 1.

[0079] Comparative Example 5 (Bare Rotary Immersion Method) A commercially available honeycomb ceramic rotor skeleton (without an adsorption layer) was immersed in the same MOF slurry as in Example 1. After soaking for 30 minutes, it was removed, excess slurry was blown off, and it was dried at 80°C. The immersion-drying process was repeated three times to achieve a loading capacity similar to that of Example 1 (approximately 100 kg / m³). The test results are shown in Table 1. A picture of the actual product is shown below. Figure 7 As shown in the figure. The cycle life comparison chart between Embodiment 1 and Comparative Example 5 of the present invention is shown in the figure. Figure 10 As shown.

[0080] Comparative Example 6 The process, slurry formulation, and parameters were exactly the same as in Example 1, with the only difference being that the MOF particles were replaced with commercially available molecular sieve particles (specific surface area 800 m² / g, primary particle size 2 μm), and the slurry viscosity was maintained at 800 cps (within the 100-2000 cps range of this invention). All other conditions were exactly the same as in Example 1. The test results are shown in Table 1.

[0081] Comparative Example 7 The process was exactly the same as in Example 1, except that the MOF particles were replaced with commercially available ordinary silica gel particles (not nanoparticle dispersion), sodium carboxymethyl cellulose was added as a thickener, and the slurry viscosity was adjusted to 800 cps (within the 100-2000 cps range of this invention). All other conditions were exactly the same as in Example 1. The test results are shown in Table 1. A comparison of the cycle life of Example 1 of this invention with Comparative Examples 6 and 7 is shown in the figure below. Figure 11 As shown.

[0082] Comparative Example 8 The process was exactly the same as in Example 1, except that: ZIF-8 type MOF (Zn-based) was selected, with a primary particle size of 0.8 μm and a specific surface area of ​​approximately 1600 m² / g; the slurry viscosity was adjusted to 700 cps; and the target loading was adjusted to 80 kg / m³. The test results are shown in Table 1.

[0083] Table 1: Performance Comparison of Various Examples and Comparative Examples

[0084]

[0085] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A dehumidifying impeller based on a metal-organic framework material, characterized in that, The dehumidification impeller includes: a substrate and a MOF adsorption layer loaded on the substrate; in the MOF adsorption layer, the MOF loading is 30 kg / m³ to 150 kg / m³ based on the total volume of the impeller, and the primary particle size of the MOF particles is 0.1 μm to 5 μm; the MOF adsorption layer is formed by a coating slurry with a viscosity of 100 cps to 2000 cps.

2. The dehumidifying impeller based on a metal-organic framework material according to claim 1, characterized in that, The dehumidifying impeller operates at a regeneration temperature ≤70℃, and its outlet dew point after dehumidifying the air is ≤-10℃.

3. The dehumidifying impeller based on a metal-organic framework material according to claim 1, characterized in that, In the MOF adsorption layer, the MOF material is an aluminum-based, iron-based, zirconium-based, or chromium-based metal-organic framework material with a specific surface area of ​​500-4000 m² / g.

4. The dehumidifying impeller based on a metal-organic framework material according to claim 3, characterized in that, The MOF is selected from MIL-101(Cr), MIL-101(Fe), MIL-100(Fe), MIL-100(Al), MIL-53(Al), MIL-53(Cr), UiO-66(Zr), UiO-66-NH2(Zr), MOF-801(Zr), MOF-808 (Zr), CAU-1(Al), CAU-10(Al), NU-1000(Zr), Al-fumarate, MIL-96(Al), MIL-120(Al), MIL-160(Al), Cr-soc-MOF-1, MOF-303(Al) or MOF-841(Zr).

5. A dehumidifying impeller based on a metal-organic framework material according to claim 1, characterized in that, The substrate is fiberglass cloth.

6. The method for preparing a dehumidifying rotor based on a metal-organic framework material according to claim 1, characterized in that, Includes the following steps: Step 1: Coating and Molding A coating slurry is applied to a planar substrate in one step, and after drying, a MOF-substrate composite sheet with a MOF adsorption layer is formed; the viscosity of the coating slurry is 100 cps to 2000 cps. Step 2: Pressing and Shaping The MOF-substrate composite sheet obtained in step one is pressed into a corrugated shape; Step 3: Composite Molding The corrugated composite sheet obtained in step two is combined with the MOF-substrate composite sheet obtained in step one to form a dehumidifying rotor based on metal-organic framework material.

7. The method for preparing a dehumidifying rotor based on a metal-organic framework material according to claim 6, characterized in that, The coating slurry is made by mixing MOF particles, binder and solvent.

8. The method for preparing a dehumidifying rotor based on a metal-organic framework material according to claim 1, characterized in that, The adhesive is selected from one or more of silica sol, alumina sol, and water-based organic adhesives.

9. The method for preparing a dehumidifying rotor based on a metal-organic framework material according to claim 1, characterized in that, The amount of binder added is 3% to 50% of the mass of the MOF particles.

10. A dehumidifier, characterized in that, Includes the dehumidifying impeller based on metal-organic framework material as described in claim 1.

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