Ce-MOF@cmc aerogel adsorbent, and preparation method and application thereof

Abstract

The application discloses a kind of Ce-MOF@CMC aerogel adsorbents and its preparation method and application, belong to functional materials and wastewater treatment technical field.The application first with tannic acid, cerium chloride hexahydrate as ligand carries out coordination self-assembly reaction, and Ce-MOF is obtained;After then, Ce-MOF is loaded on carboxymethyl cellulose, and Ce-MOF@CMC aerogel adsorption material is prepared.The Ce-MOF@CMC aerogel adsorption material prepared by the application can treat high concentration, high alkalinity printing and dyeing wastewater, and the dosage of adsorption material is less.

Description

Technical Field

[0001] This invention relates to a Ce-MOF@CMC aerogel adsorbent, its preparation method, and its application, belonging to the field of functional materials and wastewater treatment technology. Background Technology

[0002] Dyeing and printing wastewater refers to the general term for various wastewaters discharged during the pretreatment, dyeing, printing, and finishing processes of textile products. Dyeing and printing wastewater is characterized by high color, complex chemical composition, and high dye concentration. Conventional methods for treating dyeing and printing wastewater include biological treatment, chemical flocculation, chemical oxidation, adsorption, electrochemical methods, and membrane separation; however, methods such as biological treatment, chemical flocculation, chemical oxidation, and electrochemical methods are costly and difficult to implement. Therefore, adsorption is currently the most common method.

[0003] Wastewater purification utilizes porous adsorbents to adsorb certain components onto its surface, and then separates these adsorbents from the wastewater through separation methods, thereby achieving the effect of wastewater purification. Commonly used adsorbents include activated carbon (Cao, Y., Yang, L., Liu, F., et al. (2024) Adsorption Experiments and Mechanisms of Methylene Blue on Activated Carbon from Garden Waste via Deep Eutectic Solvents Coupling KOH Activation. Biomass and Bioenergy, 182, Article 107074. https: / / doi.org / 10.1016 / j.biombioe.2024.107074), ion exchange resins (Barman, MK, Bhattarai, A. and Saha, B. (2023) Applications of Ion Exchange Resins in Environmental Remediation. Vietnam Journal of Chemistry, 61, 533-550. https: / / doi.org / 10.1002 / vjch.202300027), modified bio-based materials (CN108658160A, CN104984742B), nanomaterials (nano Fe3O4 adsorbent (Zhang Xiaoshan, Wen Chunxiao, He Ning, et al. Research progress of adsorbent nano Fe3O4 in dye wastewater treatment [J]. Guangdong Chemical Industry, 2020, 047(024):80-81.), MOF materials (Zhou Y, Wang D, Feng QA facile synthesis of a Ce-based MOF at room temperature for effective adsorption of methylene blue [J]. CrystEngComm, 2024, 26(14):2009-2017.), etc.; however, these methods have the problem of being difficult to adsorb high-concentration, high-alkaline dyeing and printing wastewater and requiring a large amount of adsorbent.

[0004] Moreover, different dyes have very different properties, which makes it impossible to use the same adsorbent for dyes. It is also impossible to simply judge what kind of dye an adsorbent can be used to adsorb based on the properties of the raw materials. In other words, the selection of adsorbents for adsorbing dyes is also very difficult.

[0005] Furthermore, aerogels possess a three-dimensional porous structure, high porosity, and low density, properties that make them highly promising for applications in the treatment of dyeing and printing wastewater. Currently, literature (CN 117358216 A) discloses a MOF / coconut jelly composite aerogel, its preparation method, and its applications. In this composite aerogel, coconut jelly aerogel is used as the matrix, loaded with MOFs-808 (Zr). 4+ The material can be used to adsorb Rhodamine B in an acidic system with a pH of 3.0. Summary of the Invention

[0006] [Technical Issues]

[0007] Conventional methods for treating dyeing and printing wastewater have the problem of being unable to adsorb high-concentration, highly alkaline dye wastewater and requiring large amounts of adsorbent.

[0008] Choosing the right adsorbent for dye adsorption is also very difficult;

[0009] Currently, the method of combining MOF and aerogel for treating dyeing and printing wastewater cannot adsorb dyes under alkaline conditions.

[0010] [Technical Solution]

[0011] To address the aforementioned issues, this invention first uses ellagic acid and cerium chloride hexahydrate as ligands to perform a coordination self-assembly reaction, yielding Ce-MOF. Then, Ce-MOF is loaded onto carboxymethyl cellulose to prepare Ce-MOF@CMC aerogel adsorbent material. The Ce-MOF@CMC aerogel adsorbent material prepared by this invention can treat high-concentration, highly alkaline dyeing and printing wastewater, and requires a small amount of adsorbent material.

[0012] The first objective of this invention is to provide a method for preparing Ce-MOF, comprising the following steps:

[0013] (1) Add ellagic acid and cerium chloride hexahydrate to a solvent and mix evenly to obtain a mixture; wherein the molar ratio of ellagic acid and cerium chloride hexahydrate is 1:0.4-0.6;

[0014] (2) Add acetic acid to the mixture and carry out coordination self-assembly reaction at 110-125℃ for 1-3 h; after the reaction is completed, cool, wash and dry to obtain Ce-MOF.

[0015] In one embodiment of the present invention, the solvent in step (1) is a mixed solution of water and N,N-dimethylformamide, wherein the volume ratio of water to N,N-dimethylformamide is 1:1 to 3, and more preferably 1:2.

[0016] In one embodiment of the present invention, the ratio of ellagic acid, cerium chloride hexahydrate, solvent, and acetic acid in steps (1) and (2) is 1 mmol: 0.4-0.6 mmol: 10-20 mL: 7-8 mL.

[0017] In one embodiment of the present invention, after adding acetic acid in step (2), the mixture can be stirred and mixed evenly before the reaction is carried out.

[0018] In one embodiment of the present invention, the washing in step (2) is performed by washing with DMF, ethanol and deionized water in sequence.

[0019] In one embodiment of the present invention, the drying in step (2) is performed at 75-85°C for 10-20 hours.

[0020] In one embodiment of the present invention, the water used in steps (1) and (2) is preferably deionized water.

[0021] The second objective of this invention is to prepare Ce-MOF using the method described herein.

[0022] A third objective of this invention is to provide a method for preparing Ce-MOF@CMC aerogel adsorbent materials, comprising the following steps:

[0023] Ce-MOF was dispersed in a carboxymethyl cellulose solution to form a mixed solution. The mixed solution was then injected into an aluminum nitrate solution to crosslink and form microspheres. The microspheres were removed, washed, and then freeze-dried to obtain Ce-MOF@CMC aerogel adsorbent material.

[0024] In one embodiment of the present invention, the carboxymethyl cellulose solution is an aqueous solution of carboxymethyl cellulose, wherein the mass ratio of carboxymethyl cellulose to water is 1:25 to 35, more preferably 1:30.

[0025] In one embodiment of the present invention, the mass ratio of Ce-MOF to carboxymethyl cellulose solution is 5-30 mg: 1 g.

[0026] In one embodiment of the present invention, the aluminum nitrate solution is an aqueous solution of aluminum nitrate with a concentration of 2-4%, where % is a mass percentage.

[0027] In one embodiment of the present invention, the injection rate of the mixed solution is 0.3-1 mL / min.

[0028] In one embodiment of the present invention, crosslinking is performed at 20-30°C for 20-30 hours.

[0029] In one embodiment of the present invention, the microspheres can be removed by filtration.

[0030] In one embodiment of the present invention, washing is performed using water.

[0031] In one embodiment of the present invention, freeze drying is performed at -60 to -40°C for 10 to 30 hours.

[0032] The fourth objective of this invention is to prepare Ce-MOF@CMC aerogel adsorbent material using the method described herein.

[0033] The fifth objective of this invention is the application of the Ce-MOF@CMC aerogel adsorbent material described herein in the field of wastewater treatment.

[0034] In one embodiment of the present invention, the wastewater is dyeing and printing wastewater.

[0035] The sixth objective of this invention is to provide a method for treating dyeing and printing wastewater, which employs the Ce-MOF@CMC aerogel adsorbent material described in this invention.

[0036] In one embodiment of the present invention, the dyeing and printing wastewater contains cationic dyes, which are one or more of methylene blue, crystal violet, and acid chrome blue K.

[0037] In one embodiment of the present invention, the concentration range of various dyes in the dyeing and printing wastewater is 0.005-0.5 mmol / mL.

[0038] The seventh objective of this invention is to provide a methylene blue dye adsorbent that employs the Ce-MOF@CMC aerogel adsorbent material described in this invention.

[0039] [Beneficial Effects]

[0040] (1) The synthesis route of Ce-MOF and Ce-MOF@CMC aerogel adsorbent materials in this invention is short, the preparation method is simple, and the preparation conditions are mild.

[0041] (2) The Ce-MOF prepared by this invention has excellent acid and base stability.

[0042] (3) The present invention loads Ce-MOF onto cellulose aerogel, which is beneficial for secondary recycling.

[0043] (4) The raw materials used in this invention are all green and environmentally friendly materials, which are environmentally friendly and will not cause secondary pollution.

[0044] (5) The Ce-MOF@CMC aerogel adsorbent material used in this invention can treat high-concentration, high-alkaline dye wastewater, and the amount of adsorbent material used is small. Attached Figure Description

[0045] Figure 1 The image shows a SEM image of the Ce-MOF prepared in Example 1.

[0046] Figure 2 This is an XRD pattern of the Ce-MOF prepared in Example 1.

[0047] Figure 3 The image shows the acid-base stability analysis of the Ce-MOF prepared in Example 1.

[0048] Figure 4 This is a schematic diagram of the BET and pore size distribution of the Ce-MOF prepared in Example 1.

[0049] Figure 5 SEM image of Ce-MOF prepared for Comparative Example 1.

[0050] Figure 6 SEM image of Ce-MOF prepared for Comparative Example 2.

[0051] Figure 7 SEM image of Ce-MOF prepared in Comparative Example 3.

[0052] Figure 8 This is a photograph of the Ce-MOF@CMC aerogel adsorbent material prepared in Example 2.

[0053] Figure 9 The image shows the adsorption effect of the Ce-MOF@CMC aerogel adsorbent material prepared in Example 2.

[0054] Figure 10 The image shows the adsorption effect of the Ce-MOF@CMC aerogel adsorbent material prepared in Example 2 on dye wastewater at different pH levels. Detailed Implementation

[0055] The preferred embodiments of the present invention are described below. It should be understood that the embodiments are for better explanation of the present invention and are not intended to limit the present invention.

[0056] Test method:

[0057] 1. Test methods for acid-base stability:

[0058] The synthesized MOF material was immersed in solutions with different pH values ​​(pH = 3.0, 7.0, 11.0) for 24 hours, and then its XRD was tested to determine whether its structure had changed.

[0059] 2. Testing of BET and pore size distribution:

[0060] The BET test (Brunauer-Emmett-Teller test) is an analytical method used to measure the specific surface area and pore size distribution of a substance.

[0061] It is based on the principle of physical adsorption, and calculates the specific surface area of ​​the sample by measuring the relationship between the amount of gas (usually nitrogen) adsorbed on the sample surface and the relative pressure.

[0062] Raw materials used in the examples:

[0063] Ellagic acid: purity 99%, CAS: 476-66-4, purchased from Shanghai Titan Technology Co., Ltd.

[0064] Cerium chloride hexahydrate: purity 99%, purchased from Shanghai Titan Technology Co., Ltd.

[0065] Acetic acid: purity 99.5%.

[0066] Carboxymethyl cellulose: Molecular weight: 10 5 -10 6， Viscosity: 600-1000 mPa·s.

[0067] Water: Deionized water.

[0068] Example 1

[0069] A method for preparing Ce-MOF includes the following steps:

[0070] (1) Add 1 mmol ellagic acid and 0.5 mmol cerium chloride hexahydrate to 5 mL water and 10 mL N,N-dimethylformamide and mix well to obtain a mixture;

[0071] (2) Add 7.5 mL of acetic acid to the mixture, stir at 500 rpm for 30 min to mix evenly, then pour into a reaction vessel and carry out coordination self-assembly reaction at 120 °C for 2 h; after the reaction is completed, cool naturally to room temperature, wash with DMF, ethanol and deionized water in sequence, and dry at 80 °C for 12 h in a constant temperature oven to obtain Ce-MOF.

[0072] The Ce-MOF performance was tested, and the results are as follows:

[0073] Figure 1 SEM images of the Ce-MOF prepared in Example 1. Figure 1 It can be seen that the MOF material has a regular and uniform structure.

[0074] Figure 2 This is an XRD pattern of the Ce-MOF prepared in Example 1. Figure 2 It can be seen that there are no obvious impurity peaks, indicating that the sample is relatively pure and has a high degree of crystallinity.

[0075] Figure 3 The image shows the acid-base stability analysis of the Ce-MOF prepared in Example 1. Figure 3 It can be seen that MOF materials can still maintain their structural integrity under strong acid (pH=3) and strong base (pH=11) conditions.

[0076] Figure 4 This is a schematic diagram of the BET and pore size distribution of the Ce-MOF prepared in Example 1. From... Figure 4 It can be seen that Ce-MOF material has a large specific surface area, reaching 44.063 m². 2 / g, and the pore sizes are all mesopores and micropores.

[0077] Comparative Example 1

[0078] The coordination self-assembly reaction in step (2) of Example 1 was adjusted to be carried out at 120°C for 12 hours; all other steps remained the same as in Example 1, resulting in Ce-MOF (SEM image as shown). Figure 5 ).

[0079] Comparative Example 2

[0080] The coordination self-assembly reaction in step (2) of Example 1 was adjusted to be carried out at 80°C for 12 hours; all other steps remained the same as in Example 1, resulting in Ce-MOF (SEM image as shown). Figure 6 ).

[0081] Comparative Example 3

[0082] The coordination self-assembly reaction in step (2) of Example 1 was adjusted to be carried out at 25°C (room temperature) for 48 hours; all other steps remained the same as in Example 1, resulting in Ce-MOF (SEM image as shown). Figure 7 ).

[0083] The obtained Ce-MOF was subjected to performance testing, and the test results are as follows:

[0084] Table 1

[0085]

[0086]

[0087] As can be seen from Table 1, the Ce-MOF prepared in Example 1 has the largest surface area.

[0088] Example 2

[0089] A method for preparing Ce-MOF@CMC aerogel adsorbent material includes the following steps:

[0090] 15 mg of Ce-MOF prepared in Example 1 was dispersed in 1 g of carboxymethyl cellulose aqueous solution (mass ratio of carboxymethyl cellulose to water was 1:30) to form a mixed solution;

[0091] The mixed solution was then injected into a 3% aluminum nitrate aqueous solution at an injection rate of 0.5 mL / min, and cross-linked at 25°C (room temperature) for 24 h to form microspheres.

[0092] The microspheres were filtered out, washed with water, and then freeze-dried at -40℃ for 20 hours to obtain Ce-MOF@CMC aerogel adsorbent material (see image below). Figure 8 ).

[0093] Comparative Example 4

[0094] In Example 2, the carboxymethyl cellulose was replaced with polyimide;

[0095] Specifically as follows:

[0096] (1) Under nitrogen protection, diaminodiphenyl ether (ODA) (10.2 mmol, 2.041 g), biphenyl dianhydride (BPDA) (10.5 mmol, 3.089 g), and 37.620 g of N-methylpyrrolidone (NMP) were first added to a beaker. The mixture was magnetically stirred for 5 hours in an ice-water bath under nitrogen sealing to form a transparent solution, thus obtaining an anhydride-terminated PAA solution. Then, 1,3,5-tris(4-aminophenoxy)benzene (TAB) (0.2267 mmol, 0.0905 g) was added and stirred for 15 minutes to obtain a polyamic acid (PAA) solution with a certain viscosity.

[0097] (2) Add the dehydrating agent acetic anhydride (84 mmol, 7.95 mL) and the catalyst pyridine (84 mmol, 6.75 mL) to the polyamic acid (PAA) solution in sequence. After stirring for 5 minutes, add 220 mg Ce-MOF and stir until homogeneous to obtain a bright yellow viscous PI@MOF solution.

[0098] (3) The PI@MOF solution was aged in a sealed container for 24 hours, then removed and placed in acetone to replace the internal solvent. Each replacement lasted 24 hours and was repeated 3 times. Then it was soaked in 10 times the amount of tert-butanol to continue solvent replacement. Each replacement lasted 24 hours and was repeated 3 times to obtain a wet gel.

[0099] (4) The wet gel was placed directly in the cold trap of the freeze dryer and frozen at -70°C for 4 hours to ensure that the internal solvent was completely converted into a solid state. Then it was taken out and placed in the upper layer for vacuum freeze drying for 48 hours to obtain the aerogel adsorbent material.

[0100] Comparative Example 5

[0101] In Example 2, the carboxymethyl cellulose was replaced with silicon dioxide, while other aspects remained the same as in Example 2, to obtain an aerogel adsorbent material.

[0102] Specifically as follows:

[0103] (1) Mix anhydrous ethanol (EtOH), ethyl silicate (TEOS) and an appropriate amount of hydrochloric acid solution in a volume ratio of 30:1 (so that the pH value of the mixed solution is 3-4), and stir at room temperature for 90 min to obtain the precursor solution.

[0104] (2) Disperse 1g Ce-MOF in 9g ethanol to obtain a Ce-MOF dispersion; take 0.01g of Ce-MOF dispersion and add it to 1g of precursor solution to obtain Ce-MOF doped sol.

[0105] (3) After the Ce-MOF doped sol is magnetically stirred for 12 hours, it is dispersed evenly while being fully hydrolyzed. Then, 1 mol / L ammonia solution is added to 1 g of MOFs / SiO2 sol until the pH value reaches 6-7. To avoid precipitation of Ce-MOF powder, the amount of ammonia is controlled to keep the gelation time within 10 minutes.

[0106] (4) Pour the sol into the mold, age at room temperature, place the wet gel in a room temperature ethanol bath to remove any remaining impurities or moisture, and finally freeze-dry to obtain MOFs / SiO2 aerogel adsorbent material.

[0107] Example 3

[0108] A method for treating dyeing and printing wastewater, which uses the aerogel adsorbent materials prepared in Example 2 and Comparative Examples 4 and 5;

[0109] Specifically as follows:

[0110] The aerogel adsorbent was thoroughly dried, and then 10 mg of aerogel adsorbent and 10 mL of 0.5 mmol methylene blue aqueous dye solution were added to a sealable 25 mL glass bottle. Adsorption was carried out in a shaking water bath at room temperature, and the concentration of the remaining dye was measured at intervals until equilibrium was reached.

[0111] The test results are as follows:

[0112] Figure 9 This is an adsorption effect diagram of the Ce-MOF@CMC aerogel adsorbent material prepared in Example 2. From... Figure 9 It can be seen that Ce-MOF@CMC has a good adsorption capacity for the simulated pollutant methylene blue.

[0113] Table 2

[0114] Example 2 Carboxymethyl cellulose 300 Comparative Example 4 silicon dioxide 49.2 Comparative Example 5 polyimide 244

[0115] As can be seen from Table 2, the Ce-MOF@CMC aerogel adsorbent material prepared in Example 2 has a much greater adsorption capacity for methylene blue than the aerogel adsorbent materials in Comparative Examples 4 and 5.

[0116] Example 4

[0117] The mass of Ce-MOF in Example 2 was adjusted to 5 mg, 10 mg, 15 mg, 25 mg, and 30 mg, while other parameters remained the same as in Example 2, to obtain Ce-MOF@CMC aerogel adsorbent materials with different MOF loadings.

[0118] The performance of the obtained Ce-MOF@CMC aerogel adsorbent material was tested using the following methods:

[0119] The aerogel adsorbent was thoroughly dried, and then 10 mg of aerogel adsorbent and 10 mL of 0.5 mmol methylene blue aqueous dye solution were added to a sealable 25 mL glass bottle. Adsorption was carried out in a shaking water bath at room temperature, and the concentration of the remaining dye was measured at intervals until equilibrium was reached.

[0120] The test results are as follows:

[0121] Table 3

[0122] 5 150 47 10 200 62 15 (Example 2) 300 94 25 287 89 30 253 79

[0123] Note: Adsorption rate = (concentration of substance before adsorption - concentration of substance after adsorption) / concentration of substance before adsorption.

[0124] As can be seen from Table 3, the Ce-MOF@CMC aerogel adsorbent material can adsorb up to 300 mg / g of a 0.5 mmol / L methylene blue solution.

[0125] Example 5

[0126] A method for treating dyeing and printing wastewater of different pH values, which uses the aerogel adsorbent material prepared in Example 2;

[0127] Specifically as follows:

[0128] The aerogel adsorbent was thoroughly dried, and then 10 mg of aerogel adsorbent and 10 mL of 0.5 mmol methylene blue aqueous dye solution were added to a sealable 25 mL glass bottle. The pH was adjusted to 5.0, 6.0, 7.0, 8.0, 9.0, and 10.0 by adding 1 mol / L hydrochloric acid aqueous solution or 1 mol / L sodium hydroxide aqueous solution. Adsorption was carried out in a shaking water bath at room temperature, and the concentration of the remaining dye was measured at intervals until equilibrium was reached.

[0129] The test results are as follows:

[0130] Figure 10 The image shows the adsorption effect of the Ce-MOF@CMC aerogel adsorbent material prepared in Example 2 on dye wastewater at different pH levels. Figure 10 It can be seen that Ce-MOF@CMC aerogel adsorbent material has the best adsorption effect under alkaline conditions, reaching 99%.

[0131] Example 6

[0132] A method for treating dyeing and printing wastewater, which uses the aerogel adsorbent material prepared in Example 2;

[0133] Specifically as follows:

[0134] The aerogel adsorbent material was thoroughly dried, and then 10 mg of aerogel adsorbent material and 10 mL of dye solution with a concentration of 0.25 mmol were added to a sealable 25 mL glass bottle. Adsorption was carried out in a shaking water bath at room temperature, and the concentration of the remaining dye was measured at intervals until equilibrium was reached.

[0135] The dyes are methylene blue, crystal violet, acid chrome blue K, and methyl orange.

[0136] The test results are as follows:

[0137] Table 4

[0138] Methylene blue ＞99 Crystal Violet 40 Acid Chrome Blue K 35 Methyl orange 36

[0139] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the claims.

Claims

1. A method for preparing Ce-MOF@CMC aerogel adsorbent material, characterized in that, Includes the following steps: Ce-MOF was dispersed in a carboxymethyl cellulose solution to form a mixed solution. The mixed solution was then injected into an aluminum nitrate solution to crosslink and form microspheres. The microspheres were removed, washed, and then freeze-dried to obtain Ce-MOF@CMC aerogel adsorbent material. The preparation method of Ce-MOF includes the following steps: (1) Add ellagic acid and cerium chloride hexahydrate to a solvent and mix evenly to obtain a mixture; wherein the molar ratio of ellagic acid and cerium chloride hexahydrate is 1:0.4~0.6; (2) Add acetic acid to the mixture and carry out coordination self-assembly reaction at 110~125℃ for 1~3 h; after the reaction is completed, cool, wash and dry to obtain Ce-MOF.

2. The method according to claim 1, characterized in that, In steps (1) and (2), the ratio of ellagic acid, cerium chloride hexahydrate, solvent, and acetic acid is 1 mmol: 0.4~0.6 mmol: 10~20 mL: 7~8 mL.

3. The method according to claim 1, characterized in that, In step (1), the solvent is a mixed solution of water and N,N-dimethylformamide, wherein the volume ratio of water to N,N-dimethylformamide is 1:1~3.

4. The method according to claim 1, characterized in that, In step (2), the drying process involves drying at 75-85℃ for 10-20 hours.

5. The method according to claim 1, characterized in that, The carboxymethyl cellulose solution is an aqueous solution of carboxymethyl cellulose, wherein the mass ratio of carboxymethyl cellulose to water is 1:25~35.

6. The method according to claim 1, characterized in that, Aluminum nitrate solution is an aqueous solution of aluminum nitrate with a concentration of 2-4%, where % is a mass percentage.

7. The method according to claim 1, characterized in that, The mass ratio of Ce-MOF to carboxymethyl cellulose solution is 5-30 mg: 1 g.

8. The Ce-MOF@CMC aerogel adsorbent material prepared by the method of claim 1.

9. The application of the Ce-MOF@CMC aerogel adsorbent material according to claim 8 in the field of wastewater treatment.

10. A method for treating dyeing and printing wastewater, characterized in that, The Ce-MOF@CMC aerogel adsorbent material as described in claim 8 was used.

11. The method according to claim 10, characterized in that, The dyeing and printing wastewater contains cationic dyes, which are one or more of methylene blue, crystal violet, and acid chrome blue K; the concentration range of various dyes in the dyeing and printing wastewater is 0.005-0.5 mmol / mL.

12. A methylene blue dye adsorbent, characterized in that, The Ce-MOF@CMC aerogel adsorbent material as described in claim 8 was used.

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