Humidifying adsorption film with high raw material load, dry preparation method and application

Abstract

The invention discloses a high-raw-material-loading humidifying adsorption film, a dry preparation method and application, and belongs to the field of air carbon dioxide capture adsorbents. The preparation method comprises the following steps: uniformly mixing an adsorption material which is pretreated to be neutral with a fibrillation binder, and fibrillating the binder through shearing force to form a bulk fibrillated mixed material; rolling the fibrillated mixed material for multiple times to obtain a formed film material; and finally, soaking the formed membrane material in a carbonate base solution or a hydroxyl base solution for ion exchange to obtain the wetting adsorption membrane. According to the present invention, the dry method membrane preparation is achieved by using the binder fibrillation, the operation is simple, the raw material loading amount is high, the cost is low, the industrial production is convenient, and the prepared humidifying adsorption membrane has high adsorption performance and high adsorption rate on carbon dioxide under the air concentration, and has great direct air capture industrial application potential.

Description

Technical Field

[0001] The present invention belongs to the field of carbon dioxide capture adsorbents, and particularly relates to a variable humidity adsorption membrane with high raw material loading, a dry preparation method and applications thereof. Background Art

[0002] The global warming problem caused by excessive anthropogenic carbon dioxide emissions has attracted wide social attention. Carbon dioxide capture, utilization and storage technology (CCUS) is an important means to significantly reduce carbon emissions. At present, the direct air capture technology (DAC) is aimed at low-concentration carbon dioxide in the air, can be flexibly deployed and has a large volume, and is one of the important technologies to achieve carbon dioxide negative emissions.

[0003] At present, the adsorption method is mainly used for the direct air capture technology to separate carbon dioxide. Compared with the problems of large liquid phase loss and high regeneration heat consumption brought by the traditional solution absorption method, the use of solid adsorbents has significant advantages in energy conservation and consumption reduction. Common solid adsorbents include supported amines, molecular sieves, metal-organic frameworks, etc. Although these materials have continuously made breakthroughs in aspects such as adsorption capacity and adsorption rate in recent years, their adsorption performance is easily affected by interfacial water and the influence law is difficult to control. At the same time, the adsorption of excessive water will also lead to an increase in the energy consumption of thermal regeneration. Therefore, the variable humidity adsorption technology provides a new idea for the application of low-energy direct air capture technology. The variable humidity adsorption technology takes quaternary ammonium-based ionic polymer materials as the core, and realizes the adsorption-desorption of carbon dioxide by changing the water vapor pressure in the environment, that is, adsorbing in a low-humidity environment and desorbing in a high-humidity environment. The regeneration process of the material does not depend on a heat source, greatly reducing the capture energy consumption.

[0004] In recent years, people have begun to pay attention to the forming process of adsorbents, especially the membrane forming technology. The variable humidity adsorption forming materials usually exist in the form of thin films, and are mainly processed and formed by processes such as hot pressing, casting, dip coating, etc. However, the content of its adsorption components is relatively low, which greatly limits the adsorption capacity and adsorption rate. Therefore, it is urgent to develop a membrane forming design method with a high content of active adsorption components to improve the carbon dioxide adsorption performance of variable humidity adsorption membrane materials. Summary of the Invention

[0005] The purpose of the present invention is to solve the deficiencies of the prior art and provide a variable humidity adsorption membrane with high raw material loading, a dry preparation method and applications thereof. The adsorption membrane material in the present invention can realize roll-to-roll batch production, has a low cost, has high carbon dioxide adsorption performance under air concentration, and has good application prospects.

[0006] The specific technical solutions adopted by the present invention are as follows:

[0007] In the first aspect, the present invention provides a dry preparation method for a variable humidity adsorption membrane with high raw material loading, and the specific steps are as follows:

[0008] S1: Mix the adsorption material pretreated to neutrality with the fibrillated binder evenly to form a lumpy fibrillated hybrid material by shear force;

[0009] S2: Use a roller press to roll the fibrillated hybrid material obtained in step S1 several times, and then cut it to obtain a formed film material;

[0010] S3: Immerse the formed film material obtained in step S2 in a carbonate-based alkali solution or a hydroxide-based alkali solution until the ion exchange reaction is completed, and finally obtain a humidity-responsive adsorption film.

[0011] Preferably, in step S1, the adsorption material is a strong base type I resin or a strong base type II resin; the fibrillated binder is polytetrafluoroethylene.

[0012] Preferably, the pretreatment process of the adsorption material in step S1 is as follows: soak and wash the adsorption material successively with absolute ethanol, hydrochloric acid solution, and sodium hydroxide solution, then wash the soaked adsorption material with deionized water until it is neutral, dry it and grind it into powder, and screen the particle size with a sieve; the drying temperature is set at 70 °C, and the drying time is 24 - 48 h.

[0013] Preferably, the particle size of the adsorption material in step S1 is 0.03 - 0.1 mm.

[0014] Preferably, the mass ratio of the adsorption material in the fibrillated hybrid material in step S1 is 85 - 99%.

[0015] Preferably, the temperature of the roller press in step S2 is set at 25 - 80 °C, and the feeding speed is set at 2 - 6 mm / s.

[0016] Preferably, the thickness of the formed film material is 0.05 - 0.8 mm.

[0017] Preferably, the carbonate-based alkali solution in step S3 is a sodium carbonate solution or a potassium carbonate solution with a concentration of 0.5 - 2.0 mol / L, and the hydroxide-based alkali solution is a sodium hydroxide solution or a potassium hydroxide solution with a concentration of 0.5 - 2.0 mol / L; the time for soaking and carrying out the ion exchange reaction is 24 h.

[0018] In a second aspect, the present invention provides a humidity-responsive adsorption film obtained by the dry preparation method described in the first aspect.

[0019] In a third aspect, the present invention provides a method for applying the humidity-responsive adsorption film described in the second aspect to capture carbon dioxide in the air.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The dry process for preparing the humidity-variable adsorption membrane provided by the present invention is simple and easy to operate, with low material costs, and has very broad commercial application prospects. In this method, the active component content of the adsorption material is high, up to 99% at most, and the adsorption performance of the original functional material can be maximally exerted.

[0022] The humidity-variable adsorption membrane prepared by the method provided by the present invention can achieve a carbon dioxide adsorption capacity of 1.45 mol / kg under the environmental conditions of 400 ppm, 20 °C, and 10% relative humidity (RH), and the semi-adsorption time is only 4.5 min. It takes both the adsorption capacity and the adsorption rate into account, and is the humidity-variable adsorption molding material with the best comprehensive performance reported at present. Description of the Drawings

[0023] Figure 1 It is a comparison chart of the adsorption performance of the humidity-variable adsorption membranes prepared in Example 1 and Example 2;

[0024] Figure 2 It is a comparison chart of the carbon dioxide adsorption performance of the humidity-variable adsorption membranes prepared in Example 1 and Examples 3-6;

[0025] Figure 3 It is a comparison chart of the carbon dioxide adsorption performance of the humidity-variable adsorption membranes prepared in Example 1 and Examples 7-9;

[0026] Figure 4 It is a comparison chart of the carbon dioxide adsorption performance of the humidity-variable adsorption membranes prepared in Example 1 and Examples 10 and 11. Detailed Embodiments

[0027] The present invention will be further described and illustrated below in conjunction with the drawings and specific embodiments. The technical features of each embodiment in the present invention can be combined correspondingly without conflict.

[0028] Example 1

[0029] This example provides a dry method for preparing a humidity-variable adsorption membrane with a high raw material load, and the specific steps are as follows:

[0030] (1) The strong base type I resin is successively washed with absolute ethanol, hydrochloric acid solution and sodium hydroxide solution to remove impurities in the raw materials, and washed with deionized water for multiple times until the pH is approximately 7.0; after drying, it is ground into powder, and the particle size is sieved with a sieve.

[0031] (2) Select the adsorption material powder with a particle size of 0.08-0.1 mm, and mix the adsorption material powder and polytetrafluoroethylene (PTFE) evenly in a ball mill according to a mass ratio of 90:10; then mix and press in a mortar to form a lumpy fibrillated hybrid material through shear force.

[0032] (3) Adjust the temperature and rotation speed of the roll press to 80 °C and 3 cm / s respectively. Use the roll press to roll the fibrillated mixed material several times, and then cut it to obtain a formed film material with a thickness of 0.4 mm.

[0033] (4) Immerse the formed film material in a 1 mol / L sodium carbonate solution for 24 h until the ion exchange reaction is completed, and finally obtain a variable humidity adsorption film.

[0034] The variable humidity adsorption films prepared in all examples and the materials obtained in the comparative examples were all tested for carbon dioxide adsorption performance using a German NETZSCH STA449F3 synchronous thermal analyzer. The film after ion exchange with the alkaline solution was washed several times with deionized water and then placed in a crucible for testing. First, purge with nitrogen at 20 °C and 60% RH for 0.5 h to remove residual CO2, then purge with dry nitrogen at 20 °C for 1.5 h to dry the adsorption film, and finally purge with a mixed gas of 20 °C, 10% RH, and 400 ppm CO2@N2 for 4.0 h to complete the adsorption process test.

[0035] Example 2

[0036] (1) Wash the strong base type II resin successively with absolute ethanol, hydrochloric acid solution, and sodium hydroxide solution to remove impurities in the raw materials, and wash it several times with deionized water until the pH is approximately 7.0; after drying, grind it into powder and screen the particle size with a sieve.

[0037] (2) Select the adsorption material powder with a particle size of 0.08 - 0.1 mm. Mix the adsorption material powder and polytetrafluoroethylene (PTFE) evenly in a ball mill according to a mass ratio of 90:10; then mix and press in a mortar to form a mass of fibrillated mixed material through shear force.

[0038] (3) Adjust the temperature and rotation speed of the roll press to 80 °C and 3 cm / s respectively. Use the roll press to roll the fibrillated mixed material several times, and then cut it to obtain a formed film material with a thickness of 0.4 mm.

[0039] (4) Immerse the formed film material in a 1 mol / L sodium carbonate solution for 24 h until the ion exchange reaction is completed, and finally obtain a variable humidity adsorption film.

[0040] Figure 1 It is a comparison chart of the carbon dioxide adsorption performance of the variable humidity adsorption films prepared with different adsorption materials in Example 1 and Example 2. The results show that the adsorption performance of the variable humidity adsorption film prepared with strong base type I resin has a greater carbon dioxide adsorption amount and a faster adsorption rate in air concentration compared to the variable humidity adsorption film prepared with strong base type II resin.

[0041] Example 3

[0042] (1) The strong base type I resin is successively cleaned with absolute ethanol, hydrochloric acid solution and sodium hydroxide solution to remove impurities in the raw materials, and washed with deionized water for several times until the pH≈7.0; after drying, it is ground into powder and sieved by a sieve for particle size screening.

[0043] (2) Select the adsorbent material powder with a particle size of 0.08 - 0.1 mm, and mix the adsorbent material powder and polytetrafluoroethylene (PTFE) evenly in a ball mill according to the mass ratio of 85:15; then mix and press in a mortar to form a lump-like fibrillated hybrid material through shear force.

[0044] (3) Adjust the temperature and rotation speed of the roll press to 80°C and 3 cm / s respectively, use the roll press to roll the fibrillated hybrid material several times, and then cut it to obtain a formed film material with a thickness of 0.4 mm;

[0045] (4) Immerse the formed film material in 1 mol / L sodium carbonate solution for 24 h until the ion exchange reaction is completed, and finally obtain a wet adsorbent film.

[0046] Example 4

[0047] (1) The strong base type I resin is successively cleaned with absolute ethanol, hydrochloric acid solution and sodium hydroxide solution to remove impurities in the raw materials, and washed with deionized water for several times until the pH≈7.0; after drying, it is ground into powder and sieved by a sieve for particle size screening.

[0048] (2) Select the adsorbent material powder with a particle size of 0.08 - 0.1 mm, and mix the adsorbent material powder and polytetrafluoroethylene (PTFE) evenly in a ball mill according to the mass ratio of 95:5; then mix and press in a mortar to form a lump-like fibrillated hybrid material through shear force.

[0049] (3) Adjust the temperature and rotation speed of the roll press to 80°C and 3 cm / s respectively, use the roll press to roll the fibrillated hybrid material several times, and then cut it to obtain a formed film material with a thickness of 0.4 mm;

[0050] (4) Immerse the formed film material in 1 mol / L sodium carbonate solution for 24 h until the ion exchange reaction is completed, and finally obtain a wet adsorbent film.

[0051] Example 5

[0052] (1) The strong base type I resin is successively cleaned with absolute ethanol, hydrochloric acid solution and sodium hydroxide solution to remove impurities in the raw materials, and washed with deionized water for several times until the pH≈7.0; after drying, it is ground into powder and sieved by a sieve for particle size screening.

[0053] (2) Select the adsorption material powder with a particle size of 0.08 - 0.1 mm, and uniformly mix the adsorption material powder and polytetrafluoroethylene (PTFE) in a ball mill at a mass ratio of 97:3; then mix and press in a mortar to form a lump-like fibrillated hybrid material through shear force.

[0054] (3) Adjust the temperature and rotation speed of the roll press to 80 °C and 3 cm / s respectively. Use the roll press to roll the fibrillated hybrid material several times, and then cut it to obtain a formed film material with a thickness of 0.4 mm.

[0055] (4) Immerse the formed film material in a 1 mol / L sodium carbonate solution for 24 h until the ion exchange reaction is completed, and finally obtain a humidity-responsive adsorption film.

[0056] Example 6

[0057] (1) Clean the strong base type I resin successively with absolute ethanol, hydrochloric acid solution and sodium hydroxide solution to remove impurities in the raw materials, and wash it with deionized water multiple times until pH ≈ 7.0; grind it into powder after drying, and screen the particle size with a sieve.

[0058] (2) Select the adsorption material powder with a particle size of 0.08 - 0.1 mm, and uniformly mix the adsorption material powder and polytetrafluoroethylene (PTFE) in a ball mill at a mass ratio of 99:1; then mix and press in a mortar to form a lump-like fibrillated hybrid material through shear force.

[0059] (3) Adjust the temperature and rotation speed of the roll press to 80 °C and 3 cm / s respectively. Use the roll press to roll the fibrillated hybrid material several times, and then cut it to obtain a formed film material with a thickness of 0.4 mm.

[0060] (4) Immerse the formed film material in a 1 mol / L sodium carbonate solution for 24 h until the ion exchange reaction is completed, and finally obtain a humidity-responsive adsorption film.

[0061] Figure 2 It is a comparison chart of the carbon dioxide adsorption performance of the humidity-responsive adsorption films prepared in Example 1 and Examples 3 - 6. The results show that: with the increase in the addition amount of the strong base type I resin as the adsorption material, the carbon dioxide adsorption amount of the obtained humidity-responsive adsorption film at air concentration also increases significantly.

[0062] Example 7

[0063] (1) Clean the strong base type I resin successively with absolute ethanol, hydrochloric acid solution and sodium hydroxide solution to remove impurities in the raw materials, and wash it with deionized water multiple times until pH ≈ 7.0; grind it into powder after drying, and screen the particle size with a sieve.

[0064] (2) Select the adsorption material powder with a particle size of 0.08 - 0.1 mm, and uniformly mix the adsorption material powder and polytetrafluoroethylene (PTFE) in a ball mill at a mass ratio of 90:10; then mix and press in a mortar to form a lump-shaped fibrillated hybrid material through shear force.

[0065] (3) Adjust the temperature and rotation speed of the roll press to 80 °C and 3 cm / s respectively. Use the roll press to roll the fibrillated hybrid material several times, and then cut it to obtain a formed film material with a thickness of 0.05 mm.

[0066] (4) Immerse the formed film material in a 1 mol / L sodium carbonate solution for 24 h until the ion exchange reaction is completed, and finally obtain a humidity-responsive adsorption film.

[0067] The humidity-responsive adsorption film obtained in this example can achieve a carbon dioxide adsorption capacity of 1.45 mol / kg under the environmental conditions of 400 ppm, 20 °C, and 10% RH, and the half-adsorption time is only 4.5 min, taking into account both the adsorption capacity and the adsorption rate.

[0068] Example 8

[0069] (1) Wash the strong base type I resin successively with absolute ethanol, hydrochloric acid solution, and sodium hydroxide solution to remove impurities in the raw materials, and wash it with deionized water multiple times until pH ≈ 7.0; after drying, grind it into powder and screen the particle size with a sieve.

[0070] (2) Select the adsorption material powder with a particle size of 0.08 - 0.1 mm, and uniformly mix the adsorption material powder and polytetrafluoroethylene (PTFE) in a ball mill at a mass ratio of 90:10; then mix and press in a mortar to form a lump-shaped fibrillated hybrid material through shear force.

[0071] (3) Adjust the temperature and rotation speed of the roll press to 80 °C and 3 cm / s respectively. Use the roll press to roll the fibrillated hybrid material several times, and then cut it to obtain a formed film material with a thickness of 0.2 mm.

[0072] (4) Immerse the formed film material in a 1 mol / L sodium carbonate solution for 24 h until the ion exchange reaction is completed, and finally obtain a humidity-responsive adsorption film.

[0073] Example 9

[0074] (1) Wash the strong base type I resin successively with absolute ethanol, hydrochloric acid solution, and sodium hydroxide solution to remove impurities in the raw materials, and wash it with deionized water multiple times until pH ≈ 7.0; after drying, grind it into powder and screen the particle size with a sieve.

[0075] (2) Select the adsorption material powder with a particle size of 0.08 - 0.1 mm, and uniformly mix the adsorption material powder and polytetrafluoroethylene (PTFE) in a ball mill at a mass ratio of 90:10; then mix and press in a mortar to form a lump-like fibrillated hybrid material through shear force.

[0076] (3) Adjust the temperature and rotation speed of the roller press to 80 °C and 3 cm / s respectively, use the roller press to roll the fibrillated hybrid material several times, and then cut it to obtain a formed film material with a thickness of 0.8 mm.

[0077] (4) Immerse the formed film material in a 1 mol / L sodium carbonate solution for 24 h until the ion exchange reaction is completed, and finally obtain a humidity-responsive adsorption film.

[0078] Figure 3 It is a comparison chart of the carbon dioxide adsorption performance of the humidity-responsive adsorption films prepared in Example 1 and Examples 7 - 9. The results show that: at the same addition amount of the adsorption raw material (strong base type I resin), as the thickness of the formed film material decreases, the carbon dioxide adsorption amount of the finally prepared humidity-responsive adsorption film at air concentration also increases significantly.

[0079] Example 10

[0080] (1) Wash the strong base type I resin successively with absolute ethanol, hydrochloric acid solution and sodium hydroxide solution to remove impurities in the raw material, and wash it with deionized water multiple times until pH ≈ 7.0; dry it and grind it into powder, and then screen the particle size with a sieve.

[0081] (2) Select the adsorption material powder with a particle size of 0.03 - 0.054 mm, and uniformly mix the adsorption material powder and polytetrafluoroethylene (PTFE) in a ball mill at a mass ratio of 90:10; then mix and press in a mortar to form a lump-like fibrillated hybrid material through shear force.

[0082] (3) Adjust the temperature and rotation speed of the roller press to 80 °C and 3 cm / s respectively, use the roller press to roll the fibrillated hybrid material several times, and then cut it to obtain a formed film material with a thickness of 0.4 mm.

[0083] (4) Immerse the formed film material in a 1 mol / L sodium carbonate solution for 24 h until the ion exchange reaction is completed, and finally obtain a humidity-responsive adsorption film.

[0084] Example 11

[0085] (1) Wash the strong base type I resin successively with absolute ethanol, hydrochloric acid solution and sodium hydroxide solution to remove impurities in the raw material, and wash it with deionized water multiple times until pH ≈ 7.0; dry it and grind it into powder, and then screen the particle size with a sieve.

[0086] (2) Select adsorbent material powder with a particle size of 0.054 - 0.08 mm, and uniformly mix the adsorbent material powder and polytetrafluoroethylene (PTFE) in a ball mill at a mass ratio of 90:10; then mix and press in a mortar to form a lumpy fibrillated hybrid material through shear force.

[0087] (3) Adjust the temperature and rotation speed of the roller press to 80 °C and 3 cm / s respectively, and use the roller press to roll the fibrillated hybrid material several times, and then cut it to obtain a formed film material with a thickness of 0.4 mm.

[0088] (4) Immerse the formed film material in a 1 mol / L sodium carbonate solution for 24 h until the ion exchange reaction is completed, and finally obtain a humidity-responsive adsorption film.

[0089] Figure 4 It is a comparison chart of the carbon dioxide adsorption performance of the humidity-responsive adsorption films prepared in Example 1, Example 10, and Example 11. The results show that there are differences in the carbon dioxide adsorption performance of the humidity-responsive adsorption films prepared with strong base type I resins of different particle sizes. As the particle size of the adsorbent material increases, the carbon dioxide adsorption amount of the finally obtained humidity-responsive adsorption film at air concentration also slightly decreases.

[0090] Comparative Example 1

[0091] Compared with Example 1, in this comparative example, the fibrillated binder is changed from polytetrafluoroethylene to sericin, and the rest of the operations are the same as those in Example 1. However, during the mixing process, the shear force fails to form a lumpy fibrillated hybrid material.

[0092] The above-described embodiments are only a preferred solution of the present invention, but they are not intended to limit the present invention. Those of ordinary skill in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all technical solutions obtained by adopting equivalent substitution or equivalent transformation fall within the protection scope of the present invention.

Claims

1. A dry preparation method of a variable humidity adsorption membrane with high raw material loading, characterized in that, The specific steps are as follows: S1: Mix the adsorption material pretreated to neutrality with the fibrillated binder evenly, and form a mass of fibrillated hybrid material through shear force; S2: Use a roll press to roll the fibrillated hybrid material obtained in step S1 several times, and then cut it to obtain a formed membrane material; S3: Immerse the formed membrane material obtained in step S2 in a carbonate-based alkali solution or a hydroxide-based alkali solution until the ion exchange reaction is completed, and finally obtain a humidity-variable adsorption membrane.

2. The dry preparation method of the variable humidity adsorption membrane with high raw material loading according to claim 1, characterized in that, In step S1, the adsorption material uses a strong base type I resin or a strong base type II resin; the fibrillated binder uses polytetrafluoroethylene.

3. The dry preparation method of the variable humidity adsorption membrane with high raw material loading according to claim 1, wherein The pretreatment process of the adsorption material in step S1 is as follows: successively soak and wash the adsorption material with anhydrous ethanol, hydrochloric acid solution, and sodium hydroxide solution, then wash the soaked adsorption material with deionized water to neutrality, dry it and grind it into powder, and screen the particle size with a sieve; the drying temperature is set at 70°C, and the drying time is 24 - 48h.

4. The dry preparation method of the variable humidity adsorption membrane with high raw material loading according to claim 1, characterized in that, The particle size of the adsorption material in step S1 is 0.03 - 0.1mm.

5. The dry preparation method of the variable humidity adsorption membrane with high raw material loading according to claim 1, characterized in that, In the fibrillated hybrid material in step S1, the mass ratio of the adsorption material is 85 - 99%.

6. The dry preparation method of the variable humidity adsorption membrane with high raw material loading according to claim 1, characterized in that, In step S2, the temperature of the roll press is set at 25 - 80°C, and the feeding speed is set at 2 - 6mm / s.

7. The dry preparation method of the variable humidity adsorption membrane with high raw material loading according to claim 1, characterized in that, The thickness of the formed membrane material is 0.05 - 0.8mm.

8. The dry preparation method of the variable humidity adsorption membrane with high raw material loading according to claim 1, characterized in that, The carbonate-based alkali solution in step S3 uses a sodium carbonate solution or a potassium carbonate solution with a concentration of 0.5 - 2.0mol / L, and the hydroxide-based alkali solution uses a sodium hydroxide solution or a potassium hydroxide solution with a concentration of 0.5 - 2.0mol / L; the time for soaking and carrying out the ion exchange reaction is 24h.

9. A humidity-variable adsorption membrane obtained by using the dry preparation method according to any one of claims 1 - 8.

10. A method for applying the humidity-variable adsorption membrane according to claim 9 in capturing carbon dioxide in the air.

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