Preparation method and application of MOF derived porous carbon adsorbent for confining ethyl ester methyl functionalized ionic liquid

Abstract

The application relates to a preparation method and application of a novel MOF-derived porous carbon adsorbent limited in an ethyl ester methyl functionalized ionic liquid. The application takes MET(Zn) as a precursor and performs high-temperature carbonization treatment. Because the triazole ligand can release a large amount of gas as a self-template in the calcination process and affect the formation of a pore structure, the MET(Zn)-derived carbon exhibits abundant mesopores and limits the ethyl ester methyl functionalized ionic liquid in the pore diameter, so that the adsorption performance of the material is improved. After being limited by the ionic liquid, the adsorption performance of the material to sulfonamide antibiotics is obviously improved.

Description

Technical Field

[0001] This invention belongs to the field of MOF-derived porous carbon-bound ionic liquids, specifically relating to a method for preparing and applying a novel porous carbon adsorbent of confined ethyl ester methyl functionalized ionic liquid. Background Technology

[0002] Sulfonamides, as synthetic antibacterial agents, are not completely absorbed by organisms after use and are excreted into the aquatic environment in the form of the original drug or metabolites through feces and urine. The presence of sulfonamide antibiotics and their metabolites can induce resistance genes in water, posing potential toxic effects to aquatic organisms and humans. Long-term accumulation of sulfonamide antibiotics in the body can cause allergic reactions, bacterial resistance, and teratogenic, mutagenic, and carcinogenic effects. Therefore, developing adsorbents with high adsorption capacity is an urgent requirement for the removal or enrichment of sulfonamides in water.

[0003] Ionic liquids possess advantages such as good chemical stability and high solubility, making them a promising extraction solvent. However, ionic liquids are difficult to recover, hence the combination of ionic liquids with magnetic porous carbon materials. Confining the ionic liquid within porous carbon solves the problem of difficult recovery, while the ionic liquid and carbon material synergistically enhance the extraction performance of the composite material.

[0004] As research on extractants deepens, some conventional extractants can no longer meet the requirements. Therefore, it is necessary to design carbon materials with ionic liquids containing different functional groups for different target substances. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a novel MOF-derived porous carbon adsorbent based on confined ethyl ester methyl functionalized ionic liquid. This adsorbent exhibits excellent extraction capability for sulfonamide antibiotics, and also features uniform pore size and novel material composition.

[0006] The technical solution adopted in this invention is: a method for preparing a novel MOF-derived porous carbon adsorbent of confined ethyl ester methyl functionalized ionic liquid, comprising the following steps.

[0007] 1) Dissolve ZnCl2 in a mixed solvent consisting of water, ethanol, N,N-dimethylformamide (DMF), and 20-40% ammonium hydroxide by mass, and stir to form a homogeneous solution; add 1H-1,2,3-triazole, stir at room temperature for 10-13 h, collect the precipitate by centrifugation, wash with DMF and methanol, and dry to obtain the precursor MET(Zn). 。

[0008] 2) The precursor MET(Zn) is placed in a tube furnace and carbonized under a N2 atmosphere to obtain Zn-nitrogen-doped carbon material (NC).

[0009] 3) Disperse carbon material (NC) in an aqueous solution of ethyl ester methyl functionalized ionic liquid ([H3COOCmim][NTf2]), stir at room temperature for 3-6 h, wash with water, and vacuum dry to obtain a novel MOF-derived porous carbon adsorbent (ILcoo@NC) confined to ethyl ester methyl functionalized ionic liquid.

[0010] Preferably, in the above preparation method, in step 1), the solid-liquid ratio is ZnCl2:1H-1,2,3-triazole = 1g:1.0-1.5mL.

[0011] Preferably, in the above preparation method, in step 1), the mixed solvent composed of water, ethanol, N,N-dimethylformamide and ammonium hydroxide with a mass percentage concentration of 20-40% is in the volume ratio of water:ethanol:N,N-dimethylformamide:ammonium hydroxide = 3:2:2:1.

[0012] Preferably, in the above preparation method, in step 2), the carbonization is performed at 550-650℃ for 2-3 hours, with a heating rate of 5-10℃·min. -1 .

[0013] Preferably, in the above preparation method, in step 3), the mass ratio of [H3COOCmim][NTf2]:NC is 1:9.

[0014] The present invention relates to the application of a novel MOF-derived porous carbon adsorbent, which is a confined ethyl ester methyl functionalized ionic liquid, in the extraction of sulfonamide antibiotics.

[0015] Preferably, the method is as follows: a novel MOF-derived porous carbon adsorbent containing a confined ethyl ester methyl functionalized ionic liquid is added to an aqueous solution containing sulfonamide antibiotics, and the mixture is shaken and extracted at 20-25°C.

[0016] Preferably, the initial concentration of sulfonamide antibiotics is adjusted to 1-300 mg / L. -1 .

[0017] Preferably, the amount of the novel MOF-derived porous carbon adsorbent containing the confined ethyl ester methyl functionalized ionic liquid is 2-3 mg / mL.

[0018] Preferably, the sulfonamide antibiotics include sulfadiazine, sulfamethazine, sulfadiazine, or sulfamethoxazole.

[0019] The beneficial effects of this invention are as follows.

[0020] 1. This invention uses MET(Zn) as a precursor and performs high-temperature carbonization treatment. Because the triazole ligand can act as a self-template during calcination, releasing a large amount of gas and influencing the formation of pore structures, the MET(Zn)-derived carbon exhibits abundant mesopores, confining ethyl ester-methyl functionalized ionic liquids within its pore size, thereby improving the adsorption performance of the material.

[0021] 2. This invention prepares a composite adsorbent ILcoo@NC using MET(Zn) and an ethyl methyl ionic liquid ([H3COOCmim][NTf2]) for the extraction of sulfonamide antibiotics. This adsorbent exhibits high extraction capacity for sulfonamide antibiotics, and the combination of the ionic liquid and MET(Zn)-derived porous carbon enhances the material's extraction performance. The adsorption performance of this material for sulfonamide antibiotics is significantly improved after confinement by the ionic liquid. Attached Figure Description

[0022] Figure 1 These are the XRD spectra of MET(Zn) and standard MET(Zn).

[0023] Figure 2 These are the N2 adsorption / desorption isotherms for NC and ILcoo@NC.

[0024] Figure 3 This is a pore size distribution diagram for NC and IILcoo@NC.

[0025] Figure 4 This is a comparison chart of the adsorption capacity of NC and ILcoo@NC. Detailed Implementation

[0026] Example 1: A novel MOF-derived porous carbon adsorbent ILcoo@NC based on confined ethyl ester methyl functionalized ionic liquid.

[0027] (a) The preparation method is as follows

[0028] 1. Preparation of ethyl ester methyl functionalized ionic liquid ([H3COOCmim][NTf2]) 5 mmol of 1-ethyl methyl-3-methylimidazolium chloride ([H3COOCmim][Cl]) and 5.5 mmol of lithium bis(trifluoromethanesulfonylimide) (NTf2Li) were added to 5 mL of water and stirred at room temperature for 5 h. The lower ionic liquid phase was collected by centrifugation, washed three times with 3 mL of water, and then dried overnight in a vacuum oven at 60 °C to obtain the ethyl methyl functionalized ionic liquid ([H3COOCmim][NTf2]). The structural formula is as follows.

[0029]

[0030] [H3COOCmim][NTf2].

[0031] 2. Preparation of precursor MET(Zn).

[0032] ZnCl2 (1.00 g, 7.34 mmol) was dissolved in a mixed solvent consisting of 15 mL water, 10 mL ethanol, 10 mL N,N-dimethylformamide (DMF), and 5 mL 30 wt% ammonium hydroxide, and stirred to form a homogeneous solution. 1H-1,2,3-triazole (1.25 mL, 21.6 mmol) was added to the solution, and the mixture was stirred at room temperature for 12 h. The white precipitate was collected by centrifugation, washed with DMF and methanol, and dried in a vacuum oven at 60 °C for 24 h to obtain the precursor MET(Zn).

[0033] 3. Preparation of carbon materials (NC).

[0034] The dried precursor MET(Zn) was placed in a tube furnace and carbonized at 600 °C for 2 h under a N2 atmosphere (heating rate of 5 °C·min). -1 ), to obtain Zn-nitrogen-doped carbon materials (NC).

[0035] 4. Preparation of porous carbon adsorbent (ILcoo@NC).

[0036] The mass ratio of [H3COOCmim][NTf2] to NC is 1:9, and [H3COOCmim][NTf2] and NC are taken.

[0037] [H3COOCmim][NTf2] and NC were added to 50 times their weight of deionized water and stirred at room temperature for 5 h. Then, the mixture was washed once with deionized water to remove the ionic liquid on the surface of NC. After washing, the mixture was vacuum dried at 60 °C for 12 h to obtain ILcoo@NC.

[0038] (ii) Characterization

[0039] Figure 1 These are the XRD patterns of MET(Zn) and standard MET(Zn). Figure 1 As can be seen, the material and the standard spectrum are consistent at the 2 Theta characteristic peak, proving that MET(Zn) was successfully synthesized.

[0040] Figure 2 These are the N2 adsorption / desorption isotherms for NC and ILcoo@NC. (Source: [Insert Source Here]) Figure 2 As can be seen, the surface areas of NC and ILcoo@NC materials are 91.5 m² and 91.5 m², respectively. 2 g -1 76.0m 2 g -1It has a large specific surface area. Furthermore, with the addition of ionic liquid, the specific surface area and pore volume of the composite material decrease.

[0041] Figure 3 This is a BJH pore size distribution diagram for NC and ILcoo@NC. Figure 3 It can be seen that the pore size of NC is 3.859 nm, and the pore size of ILcoo@NC is 3.829 nm. Both have a uniform mesoporous structure, and the addition of ionic liquid will reduce the pore size of the material.

[0042] Figures 1-3 This invention demonstrates that ILcoo@NC material was successfully prepared, and the material has a large specific surface area and uniformly distributed mesopore size.

[0043] Example 2: Application of porous carbon adsorbent ILcoo@NC in the extraction of sulfonamide antibiotics

[0044] (I) Effects of different adsorbents on the extraction of sulfonamide antibiotics: In 5 mL of a series of initial concentrations ranging from 1 to 300 mg·L⁻¹ -1 14 mg of ILcoo@NC adsorbent and 14 mg of NC adsorbent were added to aqueous solutions of sulfonamide antibiotics (sulfadiazine, sulfamerazine, sulfamethazine, and sulfamethoxazole), respectively. The solutions were then shaken at 25°C and 250 rpm for 30 min in a constant-temperature shaking incubator, followed by centrifugation at 4000 rpm for 1 min. The supernatant was collected, and the concentration of sulfonamide antibiotics was determined by HPLC. The adsorption capacity was calculated. The maximum adsorption capacity results are shown in Table 1. Figure 4 .

[0045] Table 1

[0046] From Table 1 and Figure 4 It is evident that the introduction of ionic liquids significantly improves the adsorption performance of the material for four antibiotics. The IL provided by this invention... COO @NC showed good adsorption effects on all four antibiotics.

Claims

1. The application of a MOF-derived porous carbon adsorbent containing confined ethyl ester methyl functionalized ionic liquid in the extraction of sulfonamide antibiotics, characterized in that, The preparation method of the MOF-derived porous carbon adsorbent of the confined ethyl ester methyl functionalized ionic liquid includes the following steps: 1) Dissolve ZnCl2 in a mixed solvent consisting of water, ethanol, N,N-dimethylformamide and ammonium hydroxide with a mass percentage concentration of 20-40%, and stir to form a homogeneous solution; add 1H-1,2,3-triazole, stir at room temperature for 10-13 h, collect the precipitate by centrifugation, wash with DMF and methanol, and dry to obtain the precursor MET-Zn; 2) The precursor MET-Zn is placed in a tube furnace and carbonized under a N2 atmosphere to obtain Zn-nitrogen-doped carbon material NC; the carbonization is carried out at 550-650℃ for 2-3 hours with a heating rate of 5-10℃·min. -1 ; 3) Disperse carbon material NC in an aqueous solution of ethyl ester methyl functionalized ionic liquid [H3COOCmim][NTf2], stir at room temperature for 3-6 h, wash with water, and vacuum dry to obtain MOF-derived porous carbon adsorbent confined to ethyl ester methyl functionalized ionic liquid.

2. The application according to claim 1, characterized in that, In step 1), the solid-liquid ratio is ZnCl2:1H-1,2,3-triazole = 1g:1.0-1.5mL.

3. The application according to claim 1, characterized in that, In step 1), the mixed solvent consisting of water, ethanol, N,N-dimethylformamide and ammonium hydroxide with a mass percentage concentration of 20-40% is in the volume ratio of water:ethanol:N,N-dimethylformamide:ammonium hydroxide = 3:2:2:

1.

4. The application according to claim 1, characterized in that, In step 3), the mass ratio is [H3COOCmim][NTf2] :NC = 1:

9.

5. The application according to claim 1, characterized in that, The method is as follows: MOF-derived porous carbon adsorbent containing methyl functionalized ethyl ester ionic liquid is added to an aqueous solution containing sulfonamide antibiotics, and the mixture is extracted by shaking at 20-25℃.

6. The application according to claim 5, characterized in that, The initial concentration of sulfonamide antibiotics should be adjusted to 1-300 mg / L. -1 .

7. The application according to claim 6, characterized in that, The amount of MOF-derived porous carbon adsorbent added to the confined ethyl ester methyl functionalized ionic liquid is 2-4 mg / mL.

8. The application according to claim 1, characterized in that, The sulfonamide antibiotics include sulfadiazine, sulfamethazine, sulfadiazine, or sulfamethoxazole.

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