Composite hygroscopic material and preparation method, composite hygroscopic agent and preparation method, and application

Abstract

The present application relates to the technical field of hygroscopic materials, and specifically to a composite hygroscopic material and preparation method, a composite hygroscopic agent and preparation method, and applications. The composite hygroscopic material comprises a substrate and an organic substance loaded on the substrate; wherein the organic substance is an organic substance containing amino or sulfonic acid groups; the substrate comprises a molecular sieve; the hygroscopic material is a composite of organic and inorganic materials, which adsorbs water molecules to form bound water, thereby effectively preventing water molecules from condensing into liquid water in the pores, thereby achieving desorption of the hygroscopic material at 70°C, an adsorption depth below 40°C, and an adsorption capacity of more than 300g / kg.

Description

Technical Field

[0001] The present application relates to the technical field of hygroscopic materials, and in particular to a composite hygroscopic material and a preparation method thereof, a composite hygroscopic agent and a preparation method and application thereof. Background Art

[0002] Hygroscopic materials are materials that absorb water or moisture. They are widely used in many fields, such as in the construction industry to regulate indoor humidity to prevent mold and corrosion, in medical devices to absorb blood and other body fluids, and in food packaging to maintain food freshness.

[0003] Existing hygroscopic materials absorb water through either physical or chemical adsorption. Physical adsorption utilizes pores for adsorption, which presents a conflicting balance between the adsorption and desorption capacities of a particular substance. During the dehumidification process, water molecules condense and accumulate in the pores, resulting in a high pore adsorption potential. Consequently, conventional physical adsorption materials require a high desorption temperature. Chemical adsorption involves the reaction of hygroscopic materials with water to form corresponding salts or salts containing crystalline water. While this has high adsorption properties, it requires high desorption energy consumption. Chemical hygroscopic materials can typically only absorb a certain amount of water or moisture. Once saturated, they need to be replaced or regenerated. Regeneration requires a chemical reaction to break chemical bonds. This chemical bond breaking process requires very high reaction temperatures, increasing the cost of regenerating the material. Summary of the Invention

[0004] To address the above issues, this application proposes a hygroscopic material and preparation method, as well as a composite hygroscopic agent and its preparation method and application. The hygroscopic material utilizes hydrogen bonds to adsorb water molecules. Desorption requires only the energy required to break the hydrogen bonds to achieve desorption and dendritic connections. Therefore, the minimum desorption temperature of the hygroscopic material is 70°C.

[0005] This application is achieved through the following technical solutions:

[0006] One of the purposes of the present application is to provide a composite hygroscopic material, comprising a substrate and an organic matter supported on the substrate;

[0007] Wherein, the organic matter is an organic matter containing an amino group or a sulfonic acid group;

[0008] The mass ratio of the organic matter to the substrate is 1:(0.2-20).

[0009] The composite hygroscopic material provided by the present application comprises a molecular sieve as a substrate and an organic matter as a main material for absorbing water molecules. The organic matter is firmly connected to the substrate in a hydrogen bond dendrite-like manner, so that when the composite hygroscopic material adsorbs water molecules, the water molecules are adsorbed on the main chain and side chains of the organic matter in a bound water state. The form of bound adsorption mainly includes hydrogen bonds or van der Waals forces between the amino functional groups and / or sulfonic acid functional groups in the organic matter and the water molecules, and the organic matter is staggered in the pores of the substrate, so that the bound water molecules cannot condense and accumulate in the composite hygroscopic material. The dehumidification depth of the composite hygroscopic material is -80°C to -40°C, and the desorption temperature is above 70°C. The saturated adsorption capacity of the composite hygroscopic material for water is 300g / kg to 700g / kg.

[0010] In some possible implementations, the substrate includes one or more of mesoporous silica, nano-silica, mesoporous alumina, nano-alumina, MOFs, activated carbon, and resin.

[0011] The second object of this application is to provide a method for preparing the composite hygroscopic material provided in this application, comprising the following steps:

[0012] Drying the mixed slurry to obtain the composite hygroscopic material;

[0013] Wherein, the mixed slurry contains an organic solution and a substrate.

[0014] The preparation method of the composite hygroscopic material provided by the present application comprises the following steps: the organic matter and the substrate in the mixed slurry are fully mixed and then dried to remove the solvent in the mixed slurry to obtain the dried composite hygroscopic material.

[0015] In some possible implementations, the mass fraction of organic matter in the organic solution is 30% to 80%.

[0016] In some possible implementations, the mass ratio of the organic solution to the substrate is (1-10):3.

[0017] In some possible implementations, the viscosity of the mixed slurry is 10 mPa·s to 1000 mPa·s.

[0018] In some possible implementations, the drying step includes at least two drying steps.

[0019] The third object of the present application is to provide a composite moisture absorbent, which comprises a carrier and a composite moisture absorbent material provided by an embodiment of the present application and loaded on the carrier;

[0020] The load capacity of the composite hygroscopic material is 20 kg / m 3~350kg / m 3 .

[0021] The composite desiccant provided herein, comprising the composite desiccant material provided in the examples of the present invention, has a dehumidification depth of -80°C to -40°C and a desorption temperature of 70°C or higher. The composite desiccant material is supported on a carrier and can be directly formed for adsorption or used in a packed bed for adsorption, providing convenience for engineering applications.

[0022] In some possible implementations, the carrier includes: one or more of glass fiber, cordierite, and honeycomb ceramics.

[0023] In some possible implementations, the particle size of the composite moisture absorbent is 50 nm to 200 nm.

[0024] The fourth object of the present application is to provide a method for preparing a composite moisture absorbent, comprising the following steps:

[0025] The mixed slurry and the carrier are subjected to loading treatment and then drying treatment to obtain the composite moisture absorbent;

[0026] The components of the mixed slurry include the composite hygroscopic material, solvent, binder and additives provided in this application.

[0027] The preparation method of the composite desiccant provided in the present application comprises loading the mixed slurry and the carrier so that the composite desiccant material in the mixed slurry is evenly loaded on the carrier; and drying to remove excess water and other impurities.

[0028] In some possible implementations, the mass ratio of the composite hygroscopic material, the solvent, the binder and the additive is (1-4): (10-20): (3-7): 0.01.

[0029] In some possible implementations, the viscosity of the mixed slurry is 10 mPa·s to 400 mPa·s. The composite moisture absorbent prepared within this viscosity range has a high loading capacity and is less likely to experience pore blocking.

[0030] In some possible implementations, the solid-liquid ratio of the carrier to the mixed slurry is 10 g:(400 ml to 1000 ml). Within this solid-liquid ratio range, the adsorbent loading can meet the requirements, thereby avoiding the pore blocking phenomenon that is easily caused by a large amount of liquid.

[0031] The fifth object of this application is to provide an application of the composite hygroscopic material provided by this application or the composite hygroscopic agent provided by this application in at least one field of lithium battery preparation, crude oil purification, fuel utilization, chemical synthesis, air water capture, flue gas dehydration, blast furnace dehumidification, warehousing and logistics, food processing, automobile aviation, building environment, electronic product processing, HVAC, and indoor dehumidification.

[0032] The application of the composite hygroscopic material or composite hygroscopic agent provided in the present application can achieve room temperature adsorption under the dew point temperature requirement of -80°C to -40°C (i.e., dehumidification depth) and low-temperature regeneration (i.e., desorption) of the composite hygroscopic material or the composite hygroscopic agent at a minimum of 70°C. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic flow chart of a method for preparing a composite hygroscopic material according to an embodiment of the present application;

[0034] Figure 2 This is a schematic diagram of the structure of the composite hygroscopic material after absorbing water according to an embodiment of the present application;

[0035] Figure 3 This is a schematic structural diagram of the composite moisture absorbent according to an embodiment of the present application;

[0036] Figure 4 This is a schematic flow chart of the preparation method of the composite moisture absorbent according to an embodiment of the present application;

[0037] Figure 5 The water vapor isothermal hygroscopic lines of the composite hygroscopic materials of Examples 1 to 5 of the present application, the composite hygroscopic agent of Example 6, and the hygroscopic materials of Comparative Examples 1 to 4;

[0038] Figure 6 Desorption curves of the composite hygroscopic materials of Examples 1 to 5 of the present application, the composite hygroscopic agent of Example 6, and the hygroscopic materials of Comparative Examples 1 to 4;

[0039] Figure 7 This is a schematic diagram of the condensation state of water when the hygroscopic material of the comparative example of this application absorbs water;

[0040] Figure 8 This is a schematic diagram of the penetration adsorption curve of the composite desiccant of Example 6 of the present application. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solutions and advantages of this application clearer, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0042] On the contrary, this application covers any alternatives, modifications, equivalents, and solutions made within the spirit and scope of this application as defined by the claims. Furthermore, to facilitate a better understanding of this application, certain specific details are described in detail below in the detailed description of this application. A person skilled in the art will be able to fully understand this application without these details.

[0043] The following examples serve to illustrate the present application. In the examples, unless otherwise indicated, parts are by weight, percentages are by weight, and temperatures are in degrees Celsius. The relationship between parts by weight and parts by volume is the same as the relationship between grams and cubic centimeters.

[0044] In this application, the term "and / or" describes the relationship between associated objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. A and B can be singular or plural. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0045] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, "at least one of a, b, or c", or "at least one of a, b, and c" can all mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0046] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. Some or all of the steps can be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0047] The terms used in the embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. The singular forms "a", "an", "the" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise.

[0048] The weights of the relevant components mentioned in the examples of this application may not only refer to the specific content of each component, but also represent the weight ratio between the components. Therefore, as long as the content of the relevant components is proportionally enlarged or reduced according to the examples of this application, it is within the scope disclosed in the examples of this application. Specifically, the mass described in the examples of this application may be a mass unit known in the chemical industry, such as μg, mg, g, kg, etc.

[0049] The terms "first" and "second" are used solely for descriptive purposes to distinguish objects, such as substances, from one another and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the technical features being referred to. For example, a first XX could also be referred to as a second XX, and similarly, a second XX could also be referred to as a first XX, without departing from the scope of the embodiments of this application. Thus, features defined as "first" or "second" may explicitly or implicitly include one or more of such features.

[0050] Hygroscopic materials are widely used in many fields. For example, in the preparation of lithium batteries, if the moisture content exceeds 0.06kPa, the lithium salt will decompose, so the required dehumidification depth must be below -25°C. For another example, the mixed C4 used as a raw material for alkylation reactions requires the water vapor partial pressure in the environment to be reduced from 0.075kPa to 0.0484kPa to 0.0499kPa, which means the required dehumidification depth must be below -28°C. Similar industries have requirements for environmental humidity. If materials such as molecular sieves, silica gel, MOFs, lithium chloride, and alumina are used, even if the adsorption depth can reach below -30°C, the desorption temperature during regeneration is high, which will result in increased energy consumption and economic losses. For example, the desorption temperature of silica gel is between 90°C and 120°C, and the desorption temperature of molecular sieves is between 120°C and 150°C.

[0051] The adsorption process of materials like molecular sieves and silica gel generally utilizes their microporous structure to adsorb and screen water molecules. During the adsorption process, the water molecules form liquid free water and form aggregates. The desorption process utilizes the fact that as temperature rises, molecular motion becomes more intense, increasing the chance of intermolecular collisions and making it easier for the adsorbed water molecules to be released from the pores. However, the desorption process cannot avoid the adsorption potential problem, requiring higher desorption temperatures and times, resulting in increased energy consumption.

[0052] In order to effectively take into account the adsorption and desorption problems of hygroscopic materials. The embodiments of the present application propose a composite hygroscopic material and a composite hygroscopic agent. The composite hygroscopic material uses an inorganic oxide as a base material and combines organic matter containing amino or sulfonic acid functional groups to make the dehumidification depth of the composite hygroscopic material -80°C to -40°C and the desorption temperature above 70°C. The composite hygroscopic material is combined with a carrier to form a composite hygroscopic agent, which not only increases the surface area of ​​the composite hygroscopic material, but also avoids the agglomeration of the hygroscopic material during the adsorption process of the composite hygroscopic material.

[0053] For the convenience of description, the following embodiments of the present application are described by taking composite hygroscopic materials and preparation methods, composite hygroscopic agents and preparation methods, and applications as examples.

[0054]

Composite hygroscopic material

[0055] One of the purposes of the embodiments of the present application is to provide a composite hygroscopic material, such as Figure 1 As shown, it includes a substrate and an organic matter loaded on the substrate;

[0056] Wherein, the organic matter is an organic matter containing an amino group or a sulfonic acid group;

[0057] The mass ratio of the organic matter to the substrate is 1:(0.2-20).

[0058] The composite hygroscopic material provided in the embodiment of the present application has a molecular sieve as a substrate and an organic matter as the main material for absorbing water molecules. The organic matter and the substrate are connected in a dendrite-like manner by hydrogen bonds, so that the substrate and the organic matter are firmly connected. When the composite hygroscopic material absorbs water molecules, the amino functional groups and / or sulfonic acid functional groups in the organic matter are hydrogen-bonded with the water molecules for adsorption, so that the water molecules will not condense and accumulate in the composite hygroscopic material. The dehumidification depth of the composite hygroscopic material is -80°C to -40°C, and the desorption temperature is above 70°C. The penetration adsorption capacity of the composite hygroscopic material is 50g / kg to 300g / kg, and the saturated adsorption capacity is 300g / kg to 700g / kg.

[0059] In the embodiment, the desorption temperature of the hygroscopic material is above 70°C. Since the composite hygroscopic material has a low desorption temperature (minimum 70°C), industrial medium-temperature waste heat can be used for heating and desorption during desorption, and there is no need to introduce a heat source for heating. For example, in the process of boiler exhaust, harmful flue gas needs to be separated and treated. The presence of moisture in this separation process will seriously affect the separation effect. Therefore, before the flue gas treatment process, a composite hygroscopic material needs to be used to absorb water. After that, the low-grade waste heat in the boiler flue gas can be used to desorb and regenerate the hygroscopic material after absorbing water. In this way, there is no need to introduce an external heat source for heating and desorption, and the low-grade waste heat is effectively utilized. In addition to boiler flue gas, the waste gas emitted by high-temperature furnaces in the steel, glass, ceramics and other industries is also low-grade waste heat. While the hygroscopic material of the embodiment of the present application is used to effectively absorb water, the low-grade waste heat of these waste gases can also be effectively utilized.

[0060] In some embodiments, the substrate comprises one or more of mesoporous silica, nanosilica, mesoporous alumina, nanoalumina, MOFs, activated carbon, and resin. In this case, these substrates have abundant pores that can not only accommodate the organic matter, but also the hydroxyl groups on the surface of the substrate form stable hydrogen bonds with the organic matter, strengthening the bonding between the organic matter and the substrate. In addition, the substrate's unique pore structure regularly confines the organic matter within the substrate. During moisture absorption, the substrate provides a high-concentration water molecule environment for the organic matter, promoting the adsorption and bonding of the organic matter to water molecules to form bound water. Under the synergistic effect of the abundant pores in the substrate and the organic matter, the dehumidification depth of the hygroscopic material is increased.

[0061] In some embodiments, the particle size of the mesoporous silica is 50 nm to 200 nm. In the exemplary embodiment, it can be a typical but non-restrictive particle size such as 50 nm, 100 nm, 150 nm, 200 nm, or a range between any two particle sizes. Within this particle size range, the mesoporous silica has a larger specific surface area and more pores, which helps to increase the amount of organic matter attached to the mesoporous silica and its adsorption capacity for water molecules, providing more moisture environment for the organic matter to absorb water. The comprehensive comparison of the dispersibility and stability of the mesoporous silica at this particle size is relatively high. In the subsequent molding process, the mesoporous silica at this particle size is not prone to agglomeration, is easier to disperse in the solvent, and is easier to mold.

[0062] In some embodiments, the pore size of the mesoporous silica is between 2 nm and 50 nm. Examples include typical but non-limiting pore sizes such as 2 nm, 10 nm, 20 nm, 30 nm, 40 nm, and 50 nm, or any range between two pore sizes. Within this pore size range, high-molecular organic matter can more easily enter the pores and effectively achieve a regular arrangement of the organic matter within the pores, avoiding the problem of organic matter accumulation within the pores caused by excessively large pores. Furthermore, within this pore size range, after the organic matter enters the pores, there is still space left, ensuring the movement of water molecules within the pores and avoiding adsorption kinetics issues.

[0063] In some embodiments, the pore volume of the mesoporous silica is 0.3 cm 3 / g~4cm 3 / g, in the example, it can be 0.3cm 3 / g, 1cm 3 / g, 2cm 3 / g, 3cm 3 / g, 4cm 3 / g, or any range between two pore volumes. Within this pore volume range, the substrate is fully and effectively loaded with organic matter, improving the dehumidification capacity of the composite material; secondly, this pore volume also increases the transport and release rate of water molecules in the pores.

[0064] Pore ​​volume unit cm 3 / g refers to the total volume of pores contained in each gram of substrate.

[0065] In some embodiments, the specific surface area of ​​the mesoporous silica is 100 m 2 / g~500m 2 / g, in this example, it can be 100m 2 / g, 200m 2 / g、300m 2 / g, 400m 2 / g、500m 2 Typical but non-restrictive specific surface areas such as 1000 nm / g or any range between two specific surface areas are provided. Within this specific surface area range, mesoporous silica has more binding sites, which directly increases the amount of organic matter attached and improves the moisture absorption capacity of the composite material.

[0066] In some embodiments, the particle size of nano-silica is 7nm to 40nm. In the exemplary embodiment, it can be a typical but non-restrictive particle size such as 7nm, 10nm, 20nm, 30nm, 40nm, or a range between any two particle sizes. Within this particle size range, nano-silica has a larger specific surface area and more pores, which helps to increase the amount of organic matter attached to nano-silica and its adsorption capacity for water molecules, providing more moisture environment for the organic matter to absorb water. At this particle size, the comprehensive comparison of the dispersibility and stability of nano-silica is relatively high. In the subsequent molding process, nano-silica under this particle size is not prone to agglomeration, is more easily dispersed in the solvent, and is easier to mold.

[0067] In some embodiments, the pore size of the nano-silica is less than 2 nm. In exemplary embodiments, the pore size can be 0.1 nm, 0.5 nm, 0.8 nm, 1 nm, 1.5 nm, 1.9 nm, or any range between two typical but non-limiting pore sizes. Within this pore size range, the specific surface area of ​​the material is increased, and the pore volume of the nano-silica is increased, providing contact sites and space for the subsequent entry of organic matter.

[0068] In some embodiments, the specific surface area of ​​nano-silica is 300 m 2 / g~600m 2 / g, in this example, it can be 300m 2 / g, 400m 2 / g、500m 2 / g、600m 2 Typical but non-limiting specific surface areas such as 1000 nm / g or a range between any two specific surface areas are provided. Within this specific surface area range, more contact sites can be provided for the composite of organic matter and substrate.

[0069] In some embodiments, the pore volume of nano-silica is 0.8 cm 3 / g~5cm 3 / g, in this example, it can be 0.8cm 3 / g, 1cm 3 / g, 2cm 3 / g, 3cm 3 / g, 4cm 3 / g, 5cm 3 Typical but non-limiting pore volumes such as 1000 Å / g or a range between any two pore volumes can provide more space for organic matter to enter the substrate within this pore volume range.

[0070] In some embodiments, the particle size of the mesoporous alumina is 50 nm to 200 nm. In the exemplary embodiment, it can be a typical but non-limiting particle size such as 50 nm, 150 nm, 200 nm, or a range between any two particle sizes. Within this particle size range, the mesoporous alumina has a larger specific surface area and more pores, which helps to increase the amount of organic matter attached to the mesoporous alumina and its adsorption capacity for water molecules, providing more moisture environment for the organic matter to absorb water. At this particle size, the dispersibility and stability of the mesoporous alumina are relatively high. In the subsequent molding process, the mesoporous alumina at this particle size is not easy to agglomerate, is easier to disperse in the solvent, and is easier to mold.

[0071] In some embodiments, the pore size of the mesoporous alumina is between 2 nm and 20 nm. Examples include typical but non-limiting pore sizes such as 2 nm, 10 nm, 15 nm, and 20 nm, or any range between two pore sizes. Within this pore size range, high-molecular organic matter can more easily enter the pores and effectively achieve a regular arrangement within the pores, avoiding the accumulation of organic matter within the pores caused by excessively large pore sizes. Furthermore, within this pore size range, after the organic matter enters the pores, there is still space left, ensuring the movement of water molecules within the pores and avoiding adsorption kinetics issues.

[0072] In some embodiments, the specific surface area of ​​the mesoporous alumina is 100 m 2 / g~500m 2 / g, in this example, it can be 100m 2 / g, 200m 2 / g、300m 2 / g, 400m 2 / g、500m 2 Typical but non-limiting specific surface areas such as 1000 nm / g or any range between two specific surface areas can be used. Within this specific surface area range, the loading of organic matter on the substrate can be increased, thereby improving the dehumidification capacity of the composite material. Secondly, this pore volume also increases the transmission and release rate of water molecules in the pores.

[0073] In some embodiments, the pore volume of the mesoporous alumina is 0.3 cm 3 / g~5cm 3 / g, in the example, it can be 0.3cm 3 / g, 1cm 3 / g, 2cm 3 / g, 3cm 3 / g, 4cm 3 / g, 5cm 3 / g, or any range between two pore volumes. Within this pore volume range, the loading of organic matter on the substrate can be increased, thereby improving the dehumidification capacity of the composite material; secondly, this pore volume also increases the transmission and release rate of water molecules in the pores.

[0074] In some embodiments, the nano-alumina particle size is between 5 nm and 100 nm. In exemplary embodiments, the nano-alumina can be selected from typical but non-limiting particle sizes such as 5 nm, 10 nm, 40 nm, 80 nm, and 100 nm, or any range between two particle sizes. Within this particle size range, the nano-alumina has a larger specific surface area and more pores, which helps increase its ability to adhere to organic matter and adsorb water molecules, providing a more hydrated environment for the organic matter to absorb water. At this particle size, the nano-alumina exhibits a relatively high overall dispersibility and stability. During the subsequent molding process, the nano-alumina at this particle size is less likely to agglomerate, is more easily dispersed in the solvent, and is easier to mold.

[0075] In some embodiments, the pore size of the nano-alumina is between 0.3 nm and 2 nm. In exemplary embodiments, the pore size can be 0.3 nm, 0.6 nm, 0.8 nm, 1 nm, 1.5 nm, 2 nm, or any range between any two pore sizes. Within this pore size range, the specific surface area of ​​the material is increased, and the pore volume of the nano-alumina is increased, providing contact sites and space for the subsequent entry of organic matter.

[0076] In some embodiments, the specific surface area of ​​nano-alumina is 300 m 2 / g~700m 2 / g, in this example, it can be 300m 2 / g, 400m 2 / g、500m 2 / g、600m 2 / g、700m 2 / g, or a range between any two specific surface areas. Within this specific surface area range, not only can more contact sites be provided for the composite of organic matter and substrate, but the number of hydroxyl groups on the surface of mesoporous alumina is less than that of nano-silica, which will reduce the organic matter loading capacity and thus affect the moisture absorption effect of the composite hygroscopic material.

[0077] In some embodiments, the pore volume of nano-alumina is 0.6 cm 3 / g~5cm 3 / g. Within this pore volume range, more space can be provided for organic matter to enter the substrate.

[0078] In some embodiments, the organic matter comprises polyethylenediamine, monoethanolamine, diethanolamine, tetraethylenepentamine, polyethyleneimine, polyaminopropyltrimethoxysilane, polyethyleneimine-trimethoxysilane, polyamide, polytetraethylenepentamine, polydiethylenetriamine, polyphenylsulfonic acid, polymethanesulfonic acid, polyp-toluenesulfonic acid, polyethylenediaminesulfonyl halide derivatives, polyethylenediaminesulfonate derivatives, polymonoethanolaminesulfonyl halide derivatives, polymonoethanolaminesulfonate derivatives, polydiethanolaminesulfonyl halide derivatives, polydiethanolaminesulfonate derivatives, polyethyleneiminesulfonyl halide derivatives, polyethyleneiminesulfonate derivatives, polyaminopropyltrimethoxysilanesulfonyl halide derivatives. One or more of the group consisting of biological, polyaminopropyltrimethoxysilane sulfonate derivatives, polyethyleneimine-trimethoxysilane sulfonyl halide derivatives, polyethyleneimine-trimethoxysilane sulfonate derivatives, polyamide sulfonyl halide derivatives, polyamide sulfonate derivatives, tetraethylenepentamine sulfonyl halide derivatives, polytetraethylenepentamine sulfonate derivatives, polydiethylenetriamine sulfonyl halide derivatives, polydiethylenetriamine sulfonate derivatives, polyphenylenesulfonic acid sulfonyl halide derivatives, polyphenylenesulfonic acid sulfonate derivatives, polymethanesulfonic acid sulfonyl halide derivatives, polymethanesulfonic acid sulfonate derivatives, poly-p-toluenesulfonic acid sulfonyl halide derivatives, and poly-p-toluenesulfonic acid sulfonate derivatives. These organic substances have at least one amino functional group and / or sulfonic acid functional group, which can form strong hydrogen bonding with the substrate, making the prepared complex more stable. In the process of combining with water molecules, such organic substances can form strong chemical affinity with water molecules. The pore structure confines water molecules in the pores, increasing the contact space between the organic substances and water molecules. The van der Waals force on the pore surface provides the initial driving force for the initial adsorption of water molecules. The highly electronegative molecules on the surface of the organic substances then provide traction, and polar molecules are dipole-bonded with each other. Some molecules will form hydrogen bonding. With the joint promotion of multiple connection methods and multiple interaction forces, the adsorption amount of water molecules is increased.

[0079] In some embodiments, the relative molecular weight of the organic compound is between 100 and 25,000. Examples include typical but non-limiting relative molecular weights such as 100, 600, 1,000, 1,800, 8,000, 10,000, 20,000, and 25,000, or any range between any two relative molecular weights. Within this molecular weight range, the organic compound can effectively complex with the substrate without clogging the pores of the substrate.

[0080] Preparation method of composite hygroscopic material

[0081] The second purpose of the embodiment of the present application is to provide a method for preparing the composite hygroscopic material provided in the embodiment of the present application, such as Figure 1 As shown, the following steps are included:

[0082] S1. The mixed slurry is dried to obtain a composite hygroscopic material;

[0083] The mixed slurry contains an organic solution and a substrate.

[0084] The preparation method of the composite hygroscopic material provided in the present application comprises the following steps: the organic matter and the substrate in the mixed slurry are fully mixed and then dried to remove the solvent in the mixed slurry to obtain the dried composite hygroscopic material.

[0085] In some embodiments, in step S1, the organic solution includes an organic material and a solvent. The mass fraction of the organic material is 30% to 80%. In exemplary embodiments, the mass fraction can be 30%, 40%, 50%, 60%, 70%, 80%, or any other typical but non-limiting mass fraction, or a range between any two mass fractions. In this case, the organic material can be fully and effectively loaded onto the substrate.

[0086] In some embodiments, the solvent includes one or more of water, methanol, ethanol, propanol, and n-butanol. In this case, these solvents are easy to remove by drying and will not introduce new impurities.

[0087] In some embodiments, in the above step S1, the step of preparing the organic solution includes:

[0088] S10. Obtain the masses of the organic matter and the solvent respectively.

[0089] S11. Perform a first mixing of the organic matter and the solvent to obtain an organic solution.

[0090] In some embodiments, in step S11, the first mixing includes mechanical mixing or ultrasonic mixing. The mechanical mixing conditions are: stirring at a temperature of 20°C to 30°C, a rotation speed of 200 rpm to 500 rpm, and a stirring time of 30 to 300 minutes. The ultrasonic mixing conditions are: stirring at a temperature of 20°C to 30°C, an ultrasonic frequency of 10 kHz to 60 kHz, and a power of 50 W to 500 W, and a stirring time of 10 to 60 minutes. Under these first mixing conditions, the organic matter can be evenly dispersed in the solvent.

[0091] In some embodiments, mechanical mixing includes centrifugal stirring, turbine stirring, or magnetic stirring.

[0092] In some embodiments, in step S1 above, the substrate undergoes a pretreatment prior to a first mixing treatment with the organic solution; the pretreatment step includes vacuum drying the substrate at a temperature of 50°C to 110°C for 1 to 5 hours. After the pretreatment, water bound to the substrate can be further removed. Furthermore, vacuum drying at an appropriate temperature can prevent pore collapse and damage in the substrate due to rapid water loss.

[0093] In some embodiments, the vacuum degree during the vacuum drying in the pretreatment step is less than 1 mmHg. In this case, vacuum drying helps remove free water and bound water in the substrate and avoids the damage to the material caused by relying solely on temperature drying.

[0094] In some embodiments, in step S1, the mass ratio of the organic solution to the substrate is (1-10): 3. In this case, the organic solution can fully immerse the substrate, allowing the organic matter to fully enter the internal pores of the substrate and be loaded.

[0095] In some embodiments, in step S1 above, the step of preparing the mixed slurry includes adding the substrate to the organic solution, then adding 20 to 80 parts by volume of a solvent, and stirring until viscous to obtain the mixed slurry. In this case, the solvent can help the organic matter enter the pores of the substrate, and the solution is removed during the subsequent drying process, which can open up the pores and provide conditions for subsequent water molecules to enter the pores for adsorption without affecting the adsorption performance of the original organic matter.

[0096] In some embodiments, the solvent includes one or more of water, methanol, ethanol, propanol, and n-butanol. In this case, these solvents are easy to remove by drying and will not introduce new impurities.

[0097] In other embodiments, in step S1, the step of preparing the mixed slurry includes: mixing the substrate and the solvent to obtain a substrate mixed solution; and mixing the substrate mixed solution with the organic solution and stirring until viscous to obtain a mixed slurry. In this case, the composite stability and loading capacity of the organic matter can be enhanced.

[0098] In other specific embodiments, the mass fraction of the substrate in the substrate mixture is 40% to 80%. In exemplary embodiments, the mass fraction can be 40%, 50%, 60%, 70%, 80%, or any range between any two mass fractions. Within this mass fraction range, the viscosity of the prepared mixed slurry meets the requirements.

[0099] In some embodiments, in step S1, the viscosity of the mixed slurry is between 10 mPa·s and 1000 mPa·s. In exemplary embodiments, the viscosity may be 10 mPa·s, 100 mPa·s, 400 mPa·s, 800 mPa·s, 1000 mPa·s, or any range between any two viscosities, which are typical but non-limiting examples. Within this viscosity range, the organic matter is evenly dispersed in the substrate while also providing the mixed slurry with enhanced dispersibility and stability.

[0100] In some embodiments, in step S1, the drying step includes at least two drying steps. In this case, the first drying step removes free water and alcoholic solvent from the mixed slurry, and the second drying step removes bound water and solvent within the mixed slurry, thereby obtaining a completely dried and internally transparent composite hygroscopic material.

[0101] In some embodiments, in the above step S1, the drying step includes:

[0102] S12. Dry the mixed slurry at a temperature of 40°C to 100°C for 2h to 24h to obtain a first dried product.

[0103] S13. The first dried product is vacuum dried at a temperature of 80° C. to 110° C. for 1 h to 5 h to obtain a composite hygroscopic material.

[0104] In the above-mentioned drying treatment step, the mixed slurry is first dried at a temperature of 40°C to 100°C for 2h to 24h to remove free water and alcohol solvents in the mixed slurry; then vacuum drying is performed to remove bound water and solvent inside the first dried product; and finally a completely dried composite hygroscopic material is obtained.

[0105] In some embodiments, in step S12, the mixed slurry is dried using a drying oven, an oven, a hot plate, a heating mantle, a muffle furnace, or a tube furnace to obtain a first dried product. In this case, the drying equipment used is a conventional device to dry and remove free water and alcohol solution from the mixed slurry.

[0106] In some embodiments, in step S13, the vacuum degree of the first dried product during vacuum drying is less than 1 mmHg. In this case, bound water in the material can be completely removed without damaging the pore structure of the material.

[0107] In some embodiments, in step S13, the first dried product is vacuum dried using a box-type vacuum drying oven or a microwave vacuum drying oven. In this case, the box-type vacuum drying oven or the microwave vacuum drying oven provides a vacuum condition to the drying environment to remove bound water and alcohol in the first dried product.

[0108] In other embodiments, in the above step S1, the drying step includes:

[0109] S14. Dry the mixed slurry by microwave drying at a power of 100W to 1000W for 30s to 30min to obtain a first dried product.

[0110] S15. The first dried product is vacuum dried at a temperature of 50°C to 110°C for 1 hour to 5 hours to obtain a composite hygroscopic material.

[0111] In some embodiments, in step S14, the mixed slurry is dried in a microwave drying oven to obtain a first dried product. In this case, the drying equipment used is a conventional device to dry and remove free water and alcohol in the mixed slurry.

[0112]

Compound desiccant

[0113] The third object of the embodiment of the present application is to provide a composite moisture absorbent, such as Figure 3 As shown, the composite moisture absorbent includes a carrier and a composite moisture absorbent material provided by an embodiment of the present application loaded on the carrier;

[0114] The loading capacity of the composite hygroscopic material is 20kg / m 3 ~350kg / m 3 .

[0115] The composite desiccant provided in the embodiments of the present application, comprising the composite desiccant material provided in the embodiments of the present application, has a dehumidification depth of -80°C to -40°C and a desorption temperature of 70°C or above. The composite desiccant material is supported on a carrier and can be directly formed for adsorption or used in a packed bed for adsorption, providing convenience for engineering applications.

[0116] In some embodiments, the carrier comprises one or more of glass fiber, cordierite, and honeycomb ceramics. These carriers contain abundant pores and a large specific surface area, which can accommodate sufficient composite hygroscopic material. This increases the loading capacity of the composite hygroscopic material in the carrier, thereby improving the moisture absorption capacity of the composite hygroscopic material.

[0117] In some embodiments, the composite desiccant has a particle size of 50 nm to 200 nm. In exemplary embodiments, the particle size can be 50 nm, 150 nm, 200 nm, or any other typical but non-limiting particle size range. Within this particle size range, the dispersibility and stability of the slurry can be improved, the strength of the carrier can be enhanced, and the powder loss rate can be reduced.

[0118] Preparation method of composite moisture absorbent

[0119] The fourth purpose of the embodiment of the present application is to provide a method for preparing a composite moisture absorbent, such as Figure 4 As shown, the following steps are included:

[0120] X1. The mixed slurry and the carrier are loaded and dried to obtain a composite moisture absorbent;

[0121] The components of the mixed slurry include the composite hygroscopic material, solvent, binder and additives provided in the embodiments of the present application.

[0122] The preparation method of the composite desiccant provided in the embodiment of the present application is to load the mixed slurry and the carrier so that the composite desiccant material in the mixed slurry is evenly loaded on the carrier; drying can remove excess water and other impurities.

[0123] In some embodiments, in step X1, the mass ratio of the composite hygroscopic material, solvent, binder, and additive is (1-4):(10-20):(3-7):0.01. For example, the mass ratio can be 2:12:5:0.01, or any range between any two mass ratios. Within this mass ratio range, the composite hygroscopic material, solvent, binder, and additive are mixed to form a mixed slurry having a viscosity of 10 mPa·s to 400 mPa·s. The composite hygroscopic material prepared within this mass ratio range exhibits high loading capacity, high loading strength, low powder loss rate after loading, and overall good loading performance.

[0124] In some embodiments, in step X1, the solvent is one or more of water, methanol, ethanol, propanol, and n-butanol. In this case, the solvent adjusts the viscosity of the mixed slurry to meet the requirements.

[0125] In some embodiments, in step X1 above, the binder includes one or more of silica sol, polyethylene, polypropylene, acrylic acid, acrylamide, and 2-acrylamide-2-methylpropanesulfonic acid. These binders can enhance the adhesion between different materials and between the raw powder and the carrier. The binder can also improve the overall mechanical strength and stability of the loaded material.

[0126] In some embodiments, the auxiliary agent includes at least one of a dispersant and a defoaming agent.

[0127] In some embodiments, the dispersant includes one or more of acrylic acid copolymer and polyvinyl alcohol. These dispersants are mainly used to adjust the interaction between molecules to avoid agglomeration and sedimentation caused by mutual attraction between molecules.

[0128] In some embodiments, in step X1, preparing a mixed slurry includes mixing and stirring raw materials including a composite hygroscopic material, a solvent, a binder, and an additive at a temperature of 20° C. to 30° C. and a rotation speed of 200 rpm to 500 rpm for 5 to 24 hours to obtain a mixed slurry. In this case, the composite hygroscopic material in the mixed slurry is uniformly mixed and has a viscosity of 10 mPa·s to 400 mPa·s.

[0129] In some embodiments, in step X1, the viscosity of the mixed slurry is between 100 mPa·s and 400 mPa·s. For example, the viscosity can be 10 mPa·s, 100 mPa·s, 200 mPa·s, 300 mPa·s, 400 mPa·s, or any other typical but non-limiting viscosity range. The composite desiccant prepared within this viscosity range has a high loading capacity and is less susceptible to pore clogging.

[0130] In some embodiments, in step X1, the carrier is calcined before being mixed with the mixed slurry for loading. In some specific embodiments, the calcination step includes calcining at a temperature of 200°C to 600°C for 2 to 4 hours. Under these calcination conditions, impurities such as binders and crosslinkers in the carrier can be fully removed.

[0131] In some embodiments, the carrier is calcined using a drying oven, an oven, a hot plate, a heating mantle, a muffle furnace, or a tube furnace. These calcination equipments are commonly used and can meet the requirements for carrier calcination.

[0132] In some embodiments, in step X1, the solid-to-liquid ratio of the carrier to the mixed slurry is 10 g:(400 ml to 1000 ml). In exemplary embodiments, the solid-to-liquid ratio may be 10 g:400 ml, 10 g:500 ml, 10 g:600 ml, 10 g:700 ml, 10 g:800 ml, 10 g:900 ml, 10 g:1000 ml, or any range between any two solid-to-liquid ratios. Within this solid-to-liquid ratio range, the required adsorbent loading can be achieved, thereby avoiding pore plugging that may occur with a large amount of liquid.

[0133] In some embodiments, in step X1 above, the loading treatment includes the step of immersing the carrier in the mixed slurry to obtain a wet composite hygroscopic agent. In some embodiments, the immersion time is 5 to 30 minutes. Exemplary, typical but non-limiting times such as 5 minutes, 10 minutes, 15 minutes, 20 minutes, 25 minutes, and 30 minutes, or any range between two times, can be used. Within this immersion time range, the composite hygroscopic material is fully loaded, avoiding problems such as decreased solution dispersibility, reduced wettability, and accumulation within the pores due to prolonged stagnant conditions.

[0134] In some embodiments, the number of dipping is 1 to 3 times.

[0135] In some embodiments, in step X1 above, after the mixed slurry and the carrier are loaded, a static treatment is performed before drying, including the step of removing the composite desiccant obtained after impregnation from the mixed slurry and hanging it to stand. In this case, the static treatment can prevent uneven distribution of the desiccant, which may cause the solution to solidify and clog the pores after subsequent drying.

[0136] In some embodiments, the quiescent treatment time is 2 to 10 hours. Exemplary, typical but non-limiting times such as 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, and 10 hours, or any range between two times, can be used. Within this quiescent treatment time range, the pores can be fully unblocked, the uniformity of the moisture absorbent distribution can be enhanced, and subsequent drying and pore clogging can be avoided.

[0137] In some embodiments, in step X1, the drying step includes vacuum drying the impregnated composite moisture absorbent at a temperature of 50° C. to 110° C. for 5 to 10 hours to obtain a dried composite moisture absorbent. Under these vacuum drying conditions, the dried composite moisture absorbent has a water content of 1 mg / g to 10 mg / g.

[0138] In some embodiments, the composite moisture absorbent after impregnation is dried in a box-type vacuum drying oven or a microwave vacuum drying oven with a vacuum degree of less than 1 mmHg. In this case, the free and bound water in the composite moisture absorbent can be removed by using a vacuum degree of less than 1 mmHg.

[0139] In other embodiments, in step X1, the drying step includes placing the impregnated composite desiccant in a tube furnace or muffle furnace, and then introducing an inert gas at a flow rate of 200 ml / min to 5000 ml / min at 50° C. to 110° C. for 5 to 10 hours. In this case, drying the impregnated composite desiccant under an inert atmosphere can remove free water and bound water from the impregnated composite desiccant.

[0140] In some embodiments, the inert gas is one or more of nitrogen, neon, and argon.

[0141]

application

[0142] The fifth purpose of the embodiments of the present application is to provide applications of the composite hygroscopic material provided in the embodiments of the present application or the composite hygroscopic agent provided in the embodiments of the present application in the fields of lithium battery preparation, crude oil purification, fuel utilization, and chemical synthesis.

[0143] The composite hygroscopic material or composite hygroscopic agent provided in the embodiments of the present application is used in the fields of lithium battery preparation, crude oil purification, fuel utilization, and chemical synthesis. The composite hygroscopic material or composite hygroscopic agent can achieve room temperature adsorption under the dew point temperature requirement of -80°C to -40°C (i.e., dehumidification depth) and low-temperature regeneration (i.e., desorption) of the composite hygroscopic material or composite hygroscopic agent at a minimum of 70°C.

[0144] The following describes the details in conjunction with specific embodiments.

[0145] Example 1

[0146] This embodiment provides a composite hygroscopic material, including mesoporous alumina and polyethyleneimine;

[0147] The mass fraction of the mesoporous alumina is 38.5%, and the mass fraction of the polyethyleneimine is 61.5%.

[0148] The particle size of mesoporous alumina is 80nm, the pore size is 11nm, and the specific surface area is 375m 2 / g, pore volume is 1.5cm 3 / g.

[0149] The relative molecular weight of polyethyleneimine is 1800.

[0150] This embodiment also provides a method for preparing a composite hygroscopic material, comprising the steps of:

[0151] (1) Preparation of organic solution: 40 g of polyethyleneimine was dissolved in 50 ml of anhydrous methanol, and the mixture was stirred at room temperature (25° C.) and a speed of 300 rpm for 60 min using a magnetic stirrer to obtain a polyethyleneimine solution.

[0152] (2) Dry mesoporous AL2O3 under vacuum of less than 1 mmHg for 2 h.

[0153] (3) The polyethyleneimine solution, 25 g of mesoporous Al2O3, and 20 ml of anhydrous methanol were mixed and stirred with a magnetic stirrer at 25°C and 300 rpm for 12 h to obtain a mixed slurry with a viscosity of 153 mPa·s.

[0154] (4) The mixed slurry was placed in a muffle furnace, kept at a constant temperature of 50°C for 5 hours, and then placed in a box-type vacuum drying oven, and dried at a temperature of 80°C for 2 hours under a vacuum degree of less than 1 mmHg to obtain a composite hygroscopic material.

[0155] Example 2

[0156] This embodiment provides a composite hygroscopic material, including mesoporous silica and polyethyleneimine;

[0157] The mass fraction of the mesoporous silica is 38.5%, and the mass fraction of the polyethyleneimine is 61.5%.

[0158] The particle size of mesoporous silica is 70, the pore size is 5nm, and the specific surface area is 412m 2 / g, pore volume is 1.3cm 3 / g.

[0159] The relative molecular weight of polyethyleneimine is 1800.

[0160] The present application also provides a method for preparing a composite hygroscopic material. The steps are basically the same as those in Example 1, except that the substrate is mesoporous silica.

[0161] Example 3

[0162] This embodiment provides a composite hygroscopic material, including mesoporous alumina and polyphenylene sulfonic acid;

[0163] The mass fraction of the mesoporous alumina is 38.5%, and the mass fraction of the polyphenylene sulfonic acid is 61.5%.

[0164] The particle size of mesoporous alumina is 80nm, the pore size is 11nm, and the specific surface area is 375m 2 / g, pore volume is 1.5cm 3 / g.

[0165] The relative molecular weight of polyphenylene sulfonic acid is 8000.

[0166] The present application also provides a method for preparing a composite hygroscopic material. The steps are basically the same as those in Example 1, except that the organic matter is polyphenylene sulfonic acid with a relative molecular weight of 8000.

[0167] Example 4

[0168] This embodiment provides a composite hygroscopic material, including mesoporous alumina and tetraethylenepentamine;

[0169] The mass fraction of the mesoporous alumina is 38.5%, and the mass fraction of the tetraethylenepentamine is 61.5%.

[0170] The particle size of mesoporous alumina is 80nm, the pore size is 11nm, and the specific surface area is 375m 2 / g, pore volume is 1.5cm 3 / g.

[0171] The relative molecular weight of tetraethylenepentamine is 189.3.

[0172] The present application also provides a method for preparing a composite hygroscopic material. The steps are basically the same as those in Example 1, except that the organic matter is tetraethylenepentamine with a relative molecular weight of 189.3.

[0173] Example 5

[0174] This embodiment provides a composite hygroscopic material and a preparation method thereof. The material and preparation method thereof are substantially the same as those in Example 1, except that:

[0175] In the preparation method, the mixed slurry is not dried in a muffle furnace, that is, the content of step (4) is: placing the mixed slurry in a box-type vacuum drying oven, and drying it at a constant temperature of 80°C for 2 hours under a vacuum degree of less than 1 mmHg to obtain a composite hygroscopic material.

[0176] Example 6

[0177] This embodiment proposes a composite moisture absorbent, comprising glass fiber and the composite moisture absorbent material of embodiment 1. The loading amount of the composite moisture absorbent material on the glass fiber is 158 kg / m 3 .

[0178] This embodiment also provides a method for preparing a composite moisture absorbent, comprising the following steps:

[0179] 1) A composite hygroscopic material was prepared according to the preparation method of the composite hygroscopic material in Example 1.

[0180] 2) 60 g of the composite hygroscopic material, 360 g of water, 150 g of silica sol, and 0.3 g of polyvinyl alcohol were obtained, and mechanically stirred at 25° C. and 300 rpm for 10 h to obtain a mixed slurry with a viscosity of 183 mPa·s.

[0181] 3) calcining the glass fiber at 550° C. for 2 h to obtain pretreated glass fiber.

[0182] 4) The pretreated glass fiber and the mixed slurry were mixed and coated for 10 minutes, and then the wet material was taken out and allowed to stand for 5 hours to obtain an impregnated composite moisture absorbent.

[0183] 5) Drying the impregnated composite moisture absorbent at a vacuum degree of less than 1 mmHg and a temperature of 50° C. to 110° C. for 8 hours to obtain a composite moisture absorbent.

[0184] Comparative Example 1

[0185] This comparative example provides 65 g of mesoporous AL2O3 as a hygroscopic material.

[0186] Comparative Example 2

[0187] This comparative example provides 65 g of mesoporous silica gel as a hygroscopic material.

[0188] Comparative Example 3

[0189] This comparative example provides 65 g of molecular sieve as a hygroscopic material.

[0190] Comparative Example 4

[0191] This comparative example provides 65g of activated carbon as the moisture absorbing material.

[0192] In order to verify the progress of the embodiments of the present application, the composite hygroscopic materials and composite hygroscopic agents provided in Examples 1 to 6 and the hygroscopic materials provided in Comparative Examples 1 to 4 were subjected to penetration adsorption capacity, saturation adsorption capacity, and desorption regeneration experiments. The experimental steps include:

[0193] The steps for determining the penetration adsorption amount and saturated adsorption amount are as follows: the same mass of experimental materials are loaded into the penetration adsorption column, and the penetration adsorption column and the bypass are connected in parallel. Humidity probes are installed in front and behind the two, for a total of four probes. The corresponding humidity conditions are measured, and N2 is used to bring out the moisture through the water vapor generator and enter the penetration adsorption table and the bypass. The penetration adsorption table is used for adsorption, and the bypass is used as a comparison. The nitrogen flow rate is 200 ml / min. The humidity changes of the humidity probe are recorded, and the penetration adsorption amount and saturated adsorption amount are calculated. The dehumidification depth is calculated based on the humidity that can be achieved after the adsorption.

[0194] Desorption regeneration experiment: Weigh 0.2 mg of the sample after adsorption of water vapor and place it in a thermogravimetric crucible. Set the temperature from 0°C to 120°C at a rate of 2°C / min. The temperature at which the weight reaches a constant value is the desorption regeneration temperature of the sample.

[0195] The penetration adsorption capacity, saturated adsorption capacity and material agglomeration of the composite hygroscopic materials, composite hygroscopic agents provided in Examples 1 to 6 and the hygroscopic materials provided in Comparative Examples 1 to 4 obtained from the above experiments are shown in Table 1 below; the water vapor isothermal hygroscopic curves of the hygroscopic materials in Examples 1 to 5, the composite hygroscopic agent in Example 6 and the hygroscopic materials in Comparative Examples 1 to 4 are shown in Table 1 below. Figure 5 As shown ( Figure 5 The horizontal axis P / P0, P represents the current pressure of the environment, P0 represents the atmospheric pressure, and P / P0 is the relative pressure). The desorption curve is as follows Figure 6 As shown; Figure 7 Schematic diagram of the condensed state of water in the pores when the hygroscopic material provided in Comparative Examples 1 to 4 absorbs water; Figure 8 This is the adsorption penetration curve of the composite desiccant of Example 6.

[0196] Table 1

[0197]

[0198] From Table 1 above and Figures 5 to 8 It can be seen that:

[0199] ① Compared with a single inorganic hygroscopic material or an organic hygroscopic material, the composite hygroscopic material of the embodiment of the present application has a low dehumidification depth and can capture moisture with a lower water content in the environment.

[0200] ② Compared with Example 5, Example 1 has the following characteristics: since Example 5 is directly vacuum dried without muffle furnace drying, the adsorption penetration and saturated adsorption capacity of the obtained composite hygroscopic material are 188.74 / kg and 401.56g / kg, respectively, which are significantly lower than those of the composite hygroscopic material in Example 1. This is because the spatial structure collapses due to direct primary drying without secondary drying, which reduces the content of organic matter entering the substrate and affects the adsorption effect.

[0201] ③ In Example 6, glass fiber was added as a carrier of the composite hygroscopic material, and no particle agglomeration phenomenon was evident in the experiment.

[0202] ④ The composite hygroscopic materials and composite hygroscopic agents of Examples 1 to 6 of the present application can achieve room temperature adsorption under the dew point temperature requirement of -80°C to -40°C and low temperature regeneration at around 70°C.

[0203] ⑤ By the attached Figure 8 It can be seen that the moisture absorption depth of the composite desiccant of the embodiment of the present application can reach -70°C.

[0204] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A method for preparing a composite moisture absorbent, characterized in that: The steps include: The mixed slurry and the carrier are subjected to loading treatment and then drying treatment to obtain the composite moisture absorbent; The components of the mixed slurry include composite hygroscopic material, solvent, binder and additives; The preparation of the composite hygroscopic material comprises the following steps: Drying the mixed slurry to obtain the composite hygroscopic material; the mixed slurry contains an organic solution and a substrate; In the preparation of the composite hygroscopic material, the drying step includes at least two drying steps; The composite moisture absorbent comprises a carrier and the composite moisture absorbent material loaded on the carrier; The load capacity of the composite hygroscopic material is 20 kg / m 3 ~350kg / m 3 ; The composite hygroscopic material comprises a substrate and an organic matter loaded on the substrate; Wherein, the organic matter is an organic matter containing an amino group or a sulfonic acid group; The mass ratio of the organic matter to the substrate is 1:0.2-20; The carrier includes: at least one of glass fiber, cordierite, and honeycomb ceramics.

2. The method for preparing the composite moisture absorbent according to claim 1, wherein The substrate includes one or more of nano-silicon dioxide, nano-aluminum oxide, MOFs, activated carbon, and resin.

3. The preparation method of the composite moisture absorbent according to claim 1, characterized in that The particle size of the composite moisture absorbent is 50nm~200nm.

4. The method for preparing the composite moisture absorbent according to claim 1, wherein The organic solution includes organic matter and a solvent, and the solvent includes one or more of water, methanol, ethanol, propanol, and n-butanol.

5. The method for preparing the composite moisture absorbent according to claim 1, wherein The mass fraction of organic matter in the organic solution is 20% to 80%; And / or, the mass ratio of the organic solution to the substrate is 1-10:3; And / or, the viscosity of the mixed slurry is 10 mPa·s to 1000 mPa·s.

6. The method for preparing the composite moisture absorbent according to claim 1, wherein The mass ratio of the composite hygroscopic material, solvent, binder and additive is 1-4:10-20:3-7:0.01; and / or, the viscosity of the mixed slurry is 10 mPa·s to 400 mPa·s; And / or, the solid-liquid ratio of the carrier to the mixed slurry is 10g:400ml~1000ml.

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