Hydrophobic flat plate type low-temperature solid adsorption material and preparation method thereof
By preparing a low-temperature solid adsorbent material with a sparse horizontal plate structure, the problem of low adsorption capacity and selectivity of existing low-temperature adsorbent materials in high humidity environments is solved, achieving efficient CO2 capture and mechanical stability, which is suitable for industrial flue gas treatment devices.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HUANENG CHONGQING LUOWEN POWER CO LTD
- Filing Date
- 2026-01-29
- Publication Date
- 2026-05-05
AI Technical Summary
Existing low-temperature solid adsorbents have low adsorption capacity and selectivity in high humidity environments, low mass transfer efficiency, and traditional potassium-based adsorbents have high bed resistance and poor formability, making them difficult to adapt to industrial equipment.
Using potassium carbonate, alumina, or titanium dioxide as aggregate carriers, alkaline aluminum sol as binder, and polytetrafluoroethylene microspheres as hydrophobic materials, hydrophobic horizontal plate-type low-temperature solid adsorbent materials are prepared by compression molding. Combined with segmented drying and gradient calcination processes, a stable hydrophobic layer and mechanical strength are formed.
It achieves high CO2 adsorption capacity, excellent hydrophobicity and mechanical stability, reduces energy consumption, is compatible with industrial equipment, solves the adsorption capacity and mechanical stability problems of traditional adsorption materials, and is suitable for modular devices in thermal power, steel, chemical and other fields.
Smart Images
Figure CN121972138A_ABST
Abstract
Description
Technical Field
[0001] The embodiments disclosed herein belong to the field of CO2 capture material technology, specifically relating to a sparse horizontal plate-type low-temperature solid adsorbent material and its preparation method. Background Technology
[0002] The continued growth in global energy demand has led to the massive burning of fossil fuels, causing atmospheric CO2 concentrations to rise continuously. This exacerbates a series of environmental problems, including global warming and sea-level rise, posing a serious threat to ecosystems and human societal development. To achieve the "dual carbon" goal, CO2 capture, utilization, and storage (CCUS) technology has become a key pathway for reducing carbon emissions. Among these technologies, adsorption is considered a highly promising CO2 capture technology due to its advantages such as a wide operating temperature range, low equipment corrosivity, and low waste emissions.
[0003] Flue gas from industries such as thermal power, steel, and chemicals is a major source of CO2 emissions. This type of flue gas is typically characterized by high humidity and complex composition, placing stringent demands on the performance of adsorption materials. Low-temperature solid adsorbents have attracted widespread attention in industrial flue gas carbon capture due to their mild operating conditions and low energy consumption. However, current low-temperature solid adsorbent materials still face several technical bottlenecks: First, most adsorbents are highly hydrophilic. In high-humidity flue gas environments, water molecules easily compete with CO2 for adsorption active sites, and may also cause pore blockage within the adsorbent, significantly reducing CO2 adsorption capacity and selectivity. Second, while potassium-based adsorbents have advantages such as high carbonation reactivity and low deactivation rate, traditional potassium-based adsorbents are mostly granular, resulting in high bed resistance, low mass transfer efficiency, and poor formability, making them difficult to adapt to the modular and large-scale equipment requirements for industrial flue gas treatment. Third, the stability of the bond between the carrier and active material in existing adsorption materials is insufficient. During repeated adsorption-regeneration cycles, problems such as loss of active components and structural collapse easily occur, affecting the material's service life and the economic viability of industrial applications.
[0004] To address these issues, the development of low-temperature solid adsorbent materials that combine excellent hydrophobic properties, high adsorption capacity, good mechanical stability, and suitability for industrial applications has become a current research hotspot. Flat-plate adsorbent materials, due to their advantages such as large specific surface area, good gas flow, and ease of modular installation, are gradually becoming the preferred form in industrial adsorption. However, the preparation of existing flat-plate adsorbent materials often suffers from complex processes, high costs, and difficulties in balancing hydrophobic modification with adsorption activity. Summary of the Invention
[0005] The embodiments disclosed herein aim to at least solve one of the technical problems existing in the prior art, and provide a sparse horizontal plate-type low-temperature solid adsorbent material and its preparation method.
[0006] On one hand, embodiments of this disclosure provide a method for preparing a hydrophobic horizontal plate-type low-temperature solid adsorbent material, the preparation method comprising: Weigh out a first predetermined mass of potassium carbonate and add it to deionized water until it is completely dissolved to obtain a saturated aqueous solution of potassium carbonate. The second preset mass of aggregate carrier, the third preset mass of alkaline aluminum sol, and the fourth preset mass of polytetrafluoroethylene microspheres are sequentially added to the potassium carbonate saturated aqueous solution, and stirred continuously at the first preset temperature until all components are mixed evenly to form a fluid mud. The mud material is evenly spread on the surface of the metal mesh and pressed under a preset pressure to form a flat blank. The flat plate embryo is first dried at a low temperature with a second preset temperature, and then dried at a high temperature with a third preset temperature until the mass of the flat plate embryo is constant. The flat plate preform with constant mass is calcined and solidified to obtain a low-temperature solid adsorbent material with a porous horizontal plate structure.
[0007] Optionally, the mass ratio of the first preset mass to the second preset mass is 1:1 to 1.2; the mass ratio of the first preset mass to the third preset mass is 1:0.05 to 0.1; and the mass ratio of the first preset mass to the fourth preset mass is 1:0.1 to 0.2.
[0008] Optionally, the aggregate carrier is alumina or titanium dioxide, and the polytetrafluoroethylene microspheres have a particle size of 200 micrometers.
[0009] Optionally, the step of continuously stirring at a first preset temperature until all components are mixed evenly to form a fluid mud includes: continuously stirring at a temperature of 25℃~35℃ for 30min~60min to ensure that all components are fully mixed evenly to form a mud with suitable fluidity.
[0010] Optionally, the pressing under a preset pressure includes: pressing the material under a pressure of 5MPa to 10MPa for 3 to 5 minutes using a tablet press to ensure that the mud is tightly bonded to the metal mesh.
[0011] Optionally, the metal mesh is a stainless steel mesh with an aperture of 50 micrometers to 100 micrometers.
[0012] Optionally, the step of first drying the flat plate preform at a second preset low temperature and then drying it at a third preset high temperature includes: placing the flat plate preform in a drying oven, first drying it at a low temperature of 60℃~80℃ for 2 hours to 4 hours, and then raising the temperature to 100℃~120℃ for high temperature drying for 4 hours to 6 hours.
[0013] Optionally, the calcination and solidification of the flat plate preform with constant mass includes: placing the flat plate preform with constant mass into a muffle furnace, heating it to 300℃~400℃ at a heating rate of 5℃ / min~10℃ / min, holding it at that temperature for 2 hours~3 hours, and then naturally cooling it to room temperature.
[0014] On the other hand, embodiments of this disclosure also provide a sparse horizontal plate-type low-temperature solid adsorbent material, which is prepared using the preparation method described above.
[0015] The hydrophobic horizontal plate-type low-temperature solid adsorbent material and its preparation method disclosed herein have the advantages of high CO2 adsorption capacity, excellent hydrophobicity and mechanical stability. Its low-temperature applicability significantly reduces the energy consumption of industrial carbon capture, and its plate-type design is compatible with modular devices, which solves the problems of high bed resistance and poor formability of traditional particulate adsorbents, and has the potential for industrial application. Attached Figure Description
[0016] Figure 1 This is a schematic flowchart of a method for preparing a hydrophobic horizontal plate-type low-temperature solid adsorbent material according to an embodiment of the present disclosure; Figure 2 This is a schematic diagram of a sample of a hydrophobic horizontal plate-type low-temperature solid adsorbent material according to an embodiment of the present disclosure; Figure 3 for Figure 2 A schematic diagram illustrating the hydrophobic properties of the sample. Detailed Implementation
[0017] To enable those skilled in the art to better understand the technical solutions of this disclosure, the disclosure will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0018] like Figure 1 As shown, a method for preparing a hydrophobic horizontal plate-type low-temperature solid adsorbent material is provided. The preparation method includes S1, weighing a first preset mass of potassium carbonate and adding it to deionized water to completely dissolve it and obtain a saturated aqueous solution of potassium carbonate.
[0019] Specifically, in this step, a first predetermined mass of potassium carbonate is weighed, added to deionized water, and stirred at room temperature until completely dissolved to obtain a saturated aqueous solution of potassium carbonate. Using a saturated solution ensures sufficient dispersion of the active potassium carbonate, improving subsequent adsorption performance.
[0020] S2. The second preset mass of aggregate carrier, the third preset mass of alkaline aluminum sol, and the fourth preset mass of polytetrafluoroethylene microspheres are sequentially added to the potassium carbonate saturated aqueous solution, and stirred continuously at the first preset temperature until all components are mixed evenly to form a fluid slurry.
[0021] Specifically, in this step, the mass ratio of the first preset mass to the second preset mass is 1:1 to 1.2. The mass ratio of the first preset mass to the third preset mass is 1:0.05 to 0.1. The mass ratio of the first preset mass to the fourth preset mass is 1:0.1 to 0.2. That is, the mass ratio of potassium carbonate to aggregate carrier is 1:1 to 1.2. Selecting this ratio range ensures that the active material and aggregate carrier form a stable composite structure, ensuring that the aggregate carrier can provide sufficient loading sites for potassium carbonate, while avoiding excessive aggregate carrier leading to a decrease in adsorption capacity. The mass ratio of potassium carbonate to alkaline aluminum sol is 1:0.05 to 0.1. This ratio allows the alkaline aluminum sol binder to fully encapsulate the active material and aggregate carrier particles, ensuring the mechanical strength of the molded material, while avoiding excessive blockage of pores by the alkaline aluminum sol binder. The mass ratio of potassium carbonate to polytetrafluoroethylene microspheres is 1:0.1~0.2. This ratio can uniformly disperse the hydrophobic polytetrafluoroethylene microspheres in the adsorbent material without affecting the CO2 adsorption activity, thus giving the adsorbent material excellent hydrophobic properties.
[0022] The aggregate carrier is alumina or titanium dioxide, and the polytetrafluoroethylene (PTFE) microspheres have a particle size of 200 micrometers. In embodiments of this disclosure, potassium carbonate is used as the active material, alumina or titanium dioxide as the aggregate carrier, alkaline aluminum sol as the binder, and PTFE microspheres with a particle size of 200 micrometers as the hydrophobic material.
[0023] Specifically, according to the above mass ratio, alumina or titanium dioxide aggregate carrier, alkaline aluminum sol binder, and 200-micron polytetrafluoroethylene (PTFE) microspheres are sequentially added to a saturated potassium carbonate aqueous solution. The mixture is stirred continuously at 25°C to 35°C for 30 to 60 minutes to ensure thorough and uniform mixing of all components, forming a slurry with suitable flowability. Controlling the stirring temperature and time prevents raw material agglomeration and ensures consistent dispersion of all components.
[0024] S3. The mud material is evenly spread on the surface of the metal mesh and pressed under a preset pressure to form a flat blank.
[0025] Specifically, in this step, the aforementioned mud material is evenly spread on the surface of a stainless steel mesh with a pore size of 50 to 100 micrometers. The mud-covered metal mesh is then placed in a tablet press and pressed for 3 to 5 minutes under a pressure of 5 to 10 MPa to ensure a tight bond between the mud material and the metal mesh, forming a flat plate. The introduction of the metal mesh enhances the mechanical strength and structural stability of the adsorbent material, adapting it to the needs of industrial flue gas circulation.
[0026] S4. The flat plate embryo is first dried at a second preset temperature at a low temperature, and then dried at a third preset temperature at a high temperature, until the quality of the flat plate embryo is constant.
[0027] Specifically, in this step, the flat plate blank is placed in a drying oven and first dried at a low temperature of 60℃~80℃ for 2 to 4 hours, then the temperature is raised to 100℃~120℃ for 4 to 6 hours, until the quality of the flat plate blank is constant. Segmented drying can prevent cracks from forming in the flat plate blank due to rapid evaporation of moisture.
[0028] S5. The flat plate preform with constant mass is calcined and solidified to obtain a low-temperature solid adsorbent material with a porous horizontal plate structure.
[0029] Specifically, in this step, the flat plate preform with constant mass is placed in a muffle furnace and heated to 300℃~400℃ at a heating rate of 5℃ / min~10℃ / min, held at that temperature for 2 hours~3 hours, and then naturally cooled to room temperature, thus obtaining the hydrophobic plate-type low-temperature solid adsorbent material. Calcination and solidification can enhance the binding strength between the components, while ensuring the adsorption activity of the active substance and the performance stability of the hydrophobic material.
[0030] The method for preparing the hydrophobic horizontal plate-type low-temperature solid adsorbent material of the present disclosure has the following beneficial effects: (1) Synergistic optimization of hydrophobic properties and adsorption activity: 200-micron polytetrafluoroethylene microspheres are used as hydrophobic materials. By precisely controlling the mass ratio of the hydrophobic material to potassium carbonate (1:0.1~0.2), the hydrophobic material is uniformly dispersed in the adsorbent material, forming a stable hydrophobic layer on the material surface. This can effectively suppress the competition of water molecules in high-humidity flue gas for CO2 adsorption active sites, while avoiding excessive coverage of active sites by the hydrophobic material, which would lead to a decrease in adsorption capacity. This achieves a synergistic improvement of hydrophobic properties and adsorption activity.
[0031] (2) Flat plate structure design to meet industrial needs: In view of the defects of traditional granular adsorbent bed with high resistance and low mass transfer efficiency, flat plate adsorbent material is prepared by combining adsorbent material with metal mesh through a pressing process. This not only improves the mechanical strength and structural stability of adsorbent material, but also has the advantages of good gas flow and easy modular installation. It can be directly adapted to large flue gas carbon capture devices in thermal power, steel, chemical and other fields, and solves the problem of poor compatibility between existing adsorbent materials and industrial equipment.
[0032] (3) Raw material ratio and preparation process optimization: By optimizing the mass ratio of potassium carbonate to aggregate carrier (1:1~1.2) and alkaline aluminum sol binder (1:0.05~0.1), and combining the preparation process of "saturated solution mixing-segmented drying-gradient calcination", the active material is fully dispersed and the components are tightly bound. This not only improves the adsorption capacity and mechanical stability of the adsorbent material, but also simplifies the preparation process and reduces production costs. At the same time, alumina or titanium oxide is selected as aggregate carrier. Its high specific surface area, excellent thermal stability and chemical stability provide a stable loading platform for the active material, further improving the recycling performance of the material.
[0033] (4) Wide range of low temperature applications: The prepared adsorbent material can efficiently capture CO2 at low temperatures of 25℃~50℃ without high temperature operation, which significantly reduces the energy consumption of industrial carbon capture process. Compared with traditional high temperature adsorbents, it is more economical and practical, and broadens the application scenarios of low temperature solid adsorbent material in industrial flue gas carbon capture.
[0034] On the other hand, this disclosure also provides a sparse horizontal plate-type low-temperature solid adsorbent material, which is prepared by the preparation method described above. The specific steps of the preparation method can be referred to the relevant description above, and will not be elaborated here.
[0035] As a specific example, the following is a detailed illustration: Example 1 Raw material ratio: 100g potassium carbonate, 100g alumina (potassium carbonate to alumina mass ratio 1:1), 5g alkaline aluminum sol (potassium carbonate to alkaline aluminum sol mass ratio 1:0.05), 10g 200μm polytetrafluoroethylene microspheres (potassium carbonate to polytetrafluoroethylene microspheres mass ratio 1:0.1).
[0036] Preparation process: The preparation method described above is followed, wherein the calcination and solidification temperature is 300℃, the heating rate is 5℃ / min, and the holding time is 2h.
[0037] Performance test results: At a low temperature of 25℃, the CO2 adsorption capacity is 2.8 mmol / g and the water contact angle is 132°.
[0038] Example 2 Raw material ratio: 100g potassium carbonate, 110g alumina (potassium carbonate to alumina mass ratio 1:1.1), 7g alkaline aluminum sol (potassium carbonate to alkaline aluminum sol mass ratio 1:0.07), 15g 200μm polytetrafluoroethylene microspheres (potassium carbonate to polytetrafluoroethylene microspheres mass ratio 1:0.15).
[0039] Preparation process: The preparation method described above is followed, wherein the calcination and solidification temperature is 320℃, the heating rate is 6℃ / min, and the holding time is 2.5h.
[0040] Performance test results: At a low temperature of 30℃, the CO2 adsorption capacity is 3.0 mmol / g and the water contact angle is 138°.
[0041] Example 3 Raw material ratio: 100g potassium carbonate, 120g alumina (potassium carbonate to alumina mass ratio 1:1.2), 10g alkaline aluminum sol (potassium carbonate to alkaline aluminum sol mass ratio 1:0.1), 20g 200μm polytetrafluoroethylene microspheres (potassium carbonate to polytetrafluoroethylene microspheres mass ratio 1:0.2).
[0042] Preparation process: The preparation method described above is followed, wherein the calcination and curing temperature is 350℃, the heating rate is 8℃ / min, and the holding time is 3h.
[0043] Performance test results: At a low temperature of 35℃, the CO2 adsorption capacity is 2.9 mmol / g and the water contact angle is 145°.
[0044] Example 4 Raw material ratio: 100g potassium carbonate, 100g titanium dioxide (potassium carbonate to titanium dioxide mass ratio 1:1), 6g alkaline aluminum sol (potassium carbonate to alkaline aluminum sol mass ratio 1:0.06), 12g 200μm polytetrafluoroethylene microspheres (potassium carbonate to polytetrafluoroethylene microspheres mass ratio 1:0.12).
[0045] Preparation process: The preparation method described above is followed, wherein the calcination and solidification temperature is 330℃, the heating rate is 7℃ / min, and the holding time is 2.5h.
[0046] Performance test results: At a low temperature of 40℃, the CO2 adsorption capacity is 3.1 mmol / g and the water contact angle is 135°.
[0047] Example 5 Raw material ratio: 100g potassium carbonate, 115g titanium dioxide (potassium carbonate to titanium dioxide mass ratio 1:1.15), 8g alkaline aluminum sol (potassium carbonate to alkaline aluminum sol mass ratio 1:0.08), 18g 200μm polytetrafluoroethylene microspheres (potassium carbonate to polytetrafluoroethylene microspheres mass ratio 1:0.18).
[0048] Preparation process: The preparation method described above is followed, wherein the calcination temperature is 380℃, the heating rate is 9℃ / min, and the holding time is 2.5h.
[0049] Performance test results: At a low temperature of 45℃, the CO2 adsorption capacity is 2.7 mmol / g and the water contact angle is 142°.
[0050] Example 6 Raw material ratio: 100g potassium carbonate, 120g titanium dioxide (potassium carbonate to titanium dioxide mass ratio 1:1.2), 9g alkaline aluminum sol (potassium carbonate to alkaline aluminum sol mass ratio 1:0.09), 20g 200μm polytetrafluoroethylene microspheres (potassium carbonate to polytetrafluoroethylene microspheres mass ratio 1:0.2).
[0051] Preparation process: The preparation method described above is followed, wherein the calcination and curing temperature is 400℃, the heating rate is 10℃ / min, and the holding time is 3h.
[0052] Performance test results: At a low temperature of 50℃, the CO2 adsorption capacity is 2.6 mmol / g and the water contact angle is 148°.
[0053] Comparative Example Raw material ratio: 100g potassium carbonate, 100g aluminum oxide (potassium carbonate to aluminum oxide mass ratio 1:1), 5g alkaline aluminum sol (potassium carbonate to alkaline aluminum sol mass ratio 1:0.05), without adding 200μm polytetrafluoroethylene microspheres.
[0054] Preparation process: completely consistent with Example 1, calcination and curing temperature 300℃, heating rate 5℃ / min, holding time 2h.
[0055] Performance test results: At a low temperature of 25℃, the CO2 adsorption capacity is 2.5 mmol / g and the water contact angle is 78°.
[0056] like Figure 2 and Figure 3 As shown, a higher water contact angle indicates that the adsorbent material has good hydrophobic properties, which can reduce the performance degradation caused by moisture in flue gas carrying away active components during practical applications. Compared with existing unmodified potassium-based adsorbent materials, hydrophobic modification can also improve the durability of the adsorbent material.
[0057] It is understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of this disclosure, and this disclosure is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and substance of this disclosure, and these modifications and improvements are also considered to be within the scope of protection of this disclosure.
Claims
1. A method for preparing a hydrophobic horizontal plate-type low-temperature solid adsorbent material, characterized in that, The preparation method includes: Weigh out a first predetermined mass of potassium carbonate and add it to deionized water until it is completely dissolved to obtain a saturated aqueous solution of potassium carbonate. The second preset mass of aggregate carrier, the third preset mass of alkaline aluminum sol, and the fourth preset mass of polytetrafluoroethylene microspheres are sequentially added to the potassium carbonate saturated aqueous solution, and stirred continuously at the first preset temperature until all components are mixed evenly to form a fluid mud. The mud material is evenly spread on the surface of the metal mesh and pressed under a preset pressure to form a flat blank. The flat plate embryo is first dried at a low temperature with a second preset temperature, and then dried at a high temperature with a third preset temperature until the mass of the flat plate embryo is constant. The flat plate preform with constant mass is calcined and solidified to obtain a low-temperature solid adsorbent material with a porous horizontal plate structure.
2. The preparation method of the hydrophobic horizontal plate-type low-temperature solid adsorbent material according to claim 1, characterized in that, The mass ratio of the first preset mass to the second preset mass is 1:1 to 1.2; the mass ratio of the first preset mass to the third preset mass is 1:0.05 to 0.1; and the mass ratio of the first preset mass to the fourth preset mass is 1:0.1 to 0.
2.
3. The preparation method of the hydrophobic horizontal plate-type low-temperature solid adsorbent material according to claim 2, characterized in that, The aggregate carrier is alumina or titanium dioxide, and the polytetrafluoroethylene microspheres have a particle size of 200 micrometers.
4. The method for preparing the hydrophobic horizontal plate-type low-temperature solid adsorbent material according to any one of claims 1 to 3, characterized in that, The step of continuously stirring at a first preset temperature until all components are evenly mixed to form a fluid mud includes: continuously stirring at a temperature of 25℃~35℃ for 30min~60min to ensure that all components are fully and evenly mixed to form a mud with suitable fluidity.
5. The method for preparing the hydrophobic horizontal plate-type low-temperature solid adsorbent material according to any one of claims 1 to 3, characterized in that, The pressing under a preset pressure includes pressing the material for 3 to 5 minutes at a pressure of 5 MPa to 10 MPa using a tablet press, so that the mud material is tightly bonded to the metal mesh.
6. The preparation method of the hydrophobic horizontal plate-type low-temperature solid adsorbent material according to claim 5, characterized in that, The metal mesh is made of stainless steel with a pore size of 50 micrometers to 100 micrometers.
7. The method for preparing the hydrophobic horizontal plate-type low-temperature solid adsorbent material according to any one of claims 1 to 3, characterized in that, The step of drying the flat plate preform at a second preset low temperature and then at a third preset high temperature includes: placing the flat plate preform in a drying oven, first drying it at a low temperature of 60℃~80℃ for 2 hours to 4 hours, and then raising the temperature to 100℃~120℃ for high temperature drying for 4 hours to 6 hours.
8. The method for preparing the hydrophobic horizontal plate-type low-temperature solid adsorbent material according to any one of claims 1 to 3, characterized in that, The calcination and solidification of the flat plate preform with constant mass includes: placing the flat plate preform with constant mass into a muffle furnace, heating it to 300℃~400℃ at a heating rate of 5℃ / min~10℃ / min, holding it at that temperature for 2 hours~3 hours, and then allowing it to cool naturally to room temperature.
9. A low-temperature solid adsorbent material with a porous horizontal plate structure, characterized in that, The sparse horizontal plate-type low-temperature solid adsorbent material is prepared by the preparation method described in any one of claims 1 to 8.