Graphene oxide composite membrane for extracting uranium from uranium-containing wastewater and preparation method of graphene oxide composite membrane
By covalently linking graphene oxide with zwitterionic covalent organic framework materials, an efficient and stable graphene oxide composite membrane was prepared, which solved the problems of low adsorption capacity and poor stability of graphene oxide membrane in uranium-containing wastewater and achieved the effect of efficient uranium extraction.
Patent Information
- Application Number
- CN202510932313.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-07
- Publication Date
- 2025-09-23
AI Technical Summary
Existing graphene oxide membranes have low adsorption capacity and poor stability in uranium-containing wastewater, limiting their practical applications.
Graphene oxide and zwitterionic covalent organic framework materials are covalently linked through polyethyleneimine to prepare a graphene oxide composite membrane, which enhances its stability in water and improves its adsorption capacity.
A graphene oxide composite membrane with high adsorption efficiency, high adsorption capacity and high stability was achieved, solving the problems of low adsorption capacity and poor stability of graphene oxide membrane in uranium-containing wastewater.
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Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of uranium adsorption, and in particular to a graphene oxide composite membrane for extracting uranium from uranium-containing wastewater and a preparation method thereof. Background Art
[0002] Environmental pollution and resource scarcity are two major challenges facing the world today. Nuclear energy, a high-energy-density, green energy source, has attracted widespread attention and development worldwide. However, the nuclear industry inevitably produces large amounts of uranium-containing wastewater, whose high radioactivity and toxicity pose significant risks to human health and environmental safety. From the perspective of environmental remediation and human health protection, efficient extraction of uranium from wastewater is imperative.
[0003] Graphene oxide (GO) adsorbents have attracted increasing attention for uranium adsorption. The abundant oxygen-containing groups on the GO surface endow the nanosheets with excellent hydrophilicity, enabling their stable dispersion in water or other polar solvents, enabling the preparation of GO membranes by simple vacuum filtration. However, once the GO membrane is placed in an aqueous solution, water molecules in the solution can penetrate the GO interlayers, causing membrane damage. This, in turn, results in poor stability and low adsorption capacity of the GO membrane material, severely hindering its application in the actual treatment of uranium-containing wastewater. Summary of the Invention
[0004] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a graphene oxide composite membrane for extracting uranium from uranium-containing wastewater and a preparation method thereof, so as to solve the problems of low adsorption capacity and poor stability of GO membrane as an adsorbent for adsorbing uranium in the existing uranium adsorption technology field.
[0005] In order to solve the above problems, the present invention first provides a method for preparing a graphene oxide composite membrane for extracting uranium from uranium-containing wastewater, the preparation method comprising the following steps:
[0006] S1. Preparation of zwitterionic covalent organic framework materials;
[0007] S2. Obtaining graphene oxide, and performing functionalization treatment on the graphene oxide to obtain functionalized graphene oxide;
[0008] S3. Add functionalized graphene oxide and zwitterionic covalent organic framework material into deionized water, and vacuum filter on a PES substrate to obtain a graphene oxide composite membrane.
[0009] Preferably, the preparation of the zwitterionic covalent organic framework material comprises the following steps:
[0010] S4, adding ethidium bromide and 2,5-diaminobenzenesulfonic acid to a mixed solvent of dioxane and mesitylene and performing ultrasonic dispersion treatment to prepare a first mixture;
[0011] S5, adding trialdehyde phloroglucinol and glacial acetic acid to the first mixture and performing ultrasonic dispersion treatment to prepare a second mixture;
[0012] S6, placing the second mixture in liquid nitrogen for a freeze-degassed cycle, and then performing a heat treatment to prepare a third mixture;
[0013] S7. The third mixture is centrifuged and washed with acetone and ethanol respectively, and then vacuum dried to obtain a zwitterionic covalent organic framework material.
[0014] Preferably, the functionalization treatment of graphene oxide in step S2 comprises the following steps:
[0015] S8, placing graphene oxide in deionized water and performing ultrasonic stirring treatment to obtain a graphene oxide solution;
[0016] S9, adding N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (EDC / HCl) and N-hydroxysuccinimide (NHS) to the graphene oxide solution to obtain a modified graphene oxide solution;
[0017] S10, adding polyethyleneimine (PEI) to the modified graphene oxide solution to prepare functionalized graphene oxide.
[0018] Preferably, in step S3, the mass ratio of the functionalized graphene oxide to the zwitterionic covalent organic framework material is 6:5.
[0019] Preferably, the ultrasonic treatment time during the preparation of the first mixture is 20 min to 35 min, and the ultrasonic treatment time during the preparation of the second mixture is 5 min to 15 min.
[0020] Preferably, the temperature for vacuum drying the third mixture is 50°C to 70°C.
[0021] The present invention also provides a graphene oxide composite membrane for extracting uranium from uranium-containing wastewater, which is prepared by the above-mentioned preparation method.
[0022] The present invention provides a graphene oxide composite membrane for extracting uranium from uranium-containing wastewater and a preparation method thereof. Graphene oxide (GO) and a zwitterionic covalent organic framework material (XJCOF) are covalently linked via polyethyleneimine (PEI), greatly enhancing the stability of the graphene oxide membrane in water. Furthermore, the introduction of the zwitterionic covalent organic framework material can address the problems of low adsorption capacity and long adsorption time of graphene oxide-based uranium adsorbents. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 This is a flow chart of the preparation process of the graphene oxide composite membrane provided by the present invention. DETAILED DESCRIPTION
[0024] To make the purpose, technical solutions, and advantages of this application more clear, the present invention is further described below with reference to the accompanying drawings and examples. Implementation methods of the present invention include, but are not limited to, the following examples. All other embodiments obtained by persons of ordinary skill in the art based on the examples in this application without creative effort are within the scope of protection of this application.
[0025] In this embodiment, the term "and / or" is merely a description of the association relationship between associated objects, indicating that three relationships may exist. For example, A and / or B can represent three situations: A exists alone, A and B exist at the same time, and B exists alone.
[0026] In the description and claims of this embodiment, the terms "first" and "second" are used to distinguish different objects rather than to describe a specific order of objects. For example, a first target object and a second target object are used to distinguish different objects rather than to describe a specific order of objects.
[0027] In the embodiments of this application, words such as "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of this application should not be interpreted as being preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.
[0028] In the description of the embodiments of this application, unless otherwise specified, "multiple" means two or more. For example, "multiple processing units" means two or more processing units; "multiple systems" means two or more systems.
[0029] Figure 1 For the preparation process flow chart of the graphene oxide composite film provided by the present invention, refer to Figure 1 A method for preparing a graphene oxide composite membrane for extracting uranium from uranium-containing wastewater, the preparation method comprising the following steps:
[0030] S1. Preparation of zwitterionic covalent organic framework materials (XJCOF).
[0031] In a preferred embodiment, the zwitterionic covalent organic framework (XJCOF) is synthesized by a solvothermal method using ethidium bromide (EB), 2,5-diaminobenzenesulfonic acid (DABA) and trialdehyde phloroglucinol (Tp).
[0032] In a specific embodiment, the preparation of the zwitterionic covalent organic framework material comprises the following steps:
[0033] S4. Add ethidium bromide and 2,5-diaminobenzenesulfonic acid into a mixed solvent of dioxane and mesitylene and perform ultrasonic dispersion treatment to prepare a first mixture.
[0034] Wherein, the ultrasonic treatment time during the preparation of the first mixture is 20 min to 35 min.
[0035] S5. Add trialdehyde phloroglucinol and glacial acetic acid to the first mixture and perform ultrasonic dispersion treatment to prepare a second mixture.
[0036] Wherein, the ultrasonic treatment time during the preparation of the second mixture is 5 min to 15 min.
[0037] S6, placing the second mixture in liquid nitrogen for a freeze-degassed cycle, and then performing a heat treatment to prepare a third mixture;
[0038] In a specific embodiment, the second mixture is placed in liquid nitrogen and freeze-degassed for three cycles, and then reacted at 120° C. for 3 days to prepare a third mixture;
[0039] S7. The third mixture is centrifuged and washed with acetone and ethanol respectively, and then vacuum dried to obtain a zwitterionic covalent organic framework material.
[0040] Wherein, the temperature for vacuum drying the third mixture in step S7 is 50° C. to 70° C.
[0041] S2. Obtain graphene oxide, and perform functionalization treatment on the graphene oxide to obtain functionalized graphene oxide.
[0042] In a preferred embodiment, the functionalization treatment of graphene oxide (GO) in step S2 comprises the following steps:
[0043] S8, placing graphene oxide in deionized water and performing ultrasonic stirring treatment to obtain a graphene oxide solution;
[0044] S9, adding N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride and N-hydroxysuccinimide to the graphene oxide solution to obtain a modified graphene oxide solution;
[0045] S10. Adding polyethyleneimine to the modified graphene oxide solution to prepare functionalized graphene oxide.
[0046] S3. Add functionalized graphene oxide and zwitterionic covalent organic framework material into deionized water, and vacuum filter on a PES substrate to obtain a graphene oxide composite membrane.
[0047] Among them, covalent organic frameworks (COFs) are a new type of porous material with a periodic two-dimensional or three-dimensional structure. The unique structure and properties of COFs give them broad application prospects in various fields such as gas separation, catalysis, biomedicine, adsorption, water treatment, and electronics. Ionic COFs (iCOFs) are an important variant of COFs materials. Their residual charges (negative or positive) can be exchanged with suitable ions, giving COFs materials new functional properties. However, most iCOFs exist in powder form, which greatly limits their reusability in uranium extraction.
[0048] The zwitterionic covalent organic framework (XJCOF) in the present invention is a covalent organic framework (COFs) with zwitterionic groups introduced to give the powdered iCOF processability. Combining it with GO improves the adsorption performance and stability of the GO membrane. At the same time, GO and XJCOF are covalently bridged by PEI, further improving the stability of the GO membrane in aqueous solution.
[0049] In a preferred embodiment, the mass ratio of the functionalized graphene oxide to the zwitterionic covalent organic framework material in step S3 is 6:5.
[0050] A graphene oxide composite membrane for extracting uranium from uranium-containing wastewater is prepared using the above-mentioned preparation method. Graphene oxide (GO) and a zwitterionic covalent organic framework (XJCOF) are covalently linked via polyethyleneimine (PEI) to synthesize a graphene oxide composite membrane with high adsorption efficiency, high adsorption capacity, and high stability.
[0051] Example 1
[0052] Example 1 provides a graphene oxide composite membrane for extracting uranium from uranium-containing wastewater, and the preparation method thereof is as follows:
[0053] (1) GO preparation
[0054] 5g of graphite powder and 115mL of H2SO4 were stirred in an ice bath for 1 hour. 30g of KMnO4 was slowly added to the solution and allowed to react at 0-3°C for 3 hours. The mixture was then heated to 50°C and stirred for 45 minutes. 400mL of H2O was added and the mixture was maintained at 50±5°C and stirred for 15 minutes. 300mL of H2O and 360g of 5% H2O2 were then added and stirred for 15 minutes. Finally, the solution was washed with deionized water to a neutral pH, resulting in the preparation of GO.
[0055] (2) Preparation of functionalized GO
[0056] 6 mg of GO was added to 250 mL of deionized water, stirred, and ultrasonicated to obtain a GO solution. 10 mg of EDC / HCl and 10 mg of NHS were added to the GO solution to obtain a modified GO solution. 5 mL of GO and 10 mg mL of NHS were added to the modified GO solution. -1 Functionalized GO was obtained by PEI reaction.
[0057] (3) Preparation of GO composite membrane
[0058] 50 mL of the above functionalized GO solution was evenly dispersed in 250 mL of deionized water, 5 mg of XJCOF was added, stirred and reacted for 6 h, and vacuum filtered onto the PES substrate membrane to obtain a GO composite membrane.
[0059] The GO composite membrane prepared in Example 1 was used to extract uranium from uranium-containing wastewater. Since the zwitterionic covalent organic framework (XJCOF) was intercalated into polyethyleneimine (PEI)-functionalized graphene oxide (GO) nanosheets, a graphene oxide composite membrane with high adsorption efficiency and high adsorption capacity was constructed, so that the graphene oxide composite membrane had high stability and low adsorption capacity when extracting uranium from uranium-containing wastewater.
[0060] In summary, the present invention covalently links graphene oxide and a zwitterionic covalent organic framework through polyethyleneimine to synthesize a graphene oxide composite membrane with high adsorption efficiency, high adsorption capacity and high stability. This can solve the problems of low adsorption capacity and poor stability of GO membrane as an adsorbent for uranium adsorption in the existing uranium adsorption technology field.
[0061] The above is only a specific implementation method of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.
Claims
1. A method for preparing a graphene oxide composite membrane for extracting uranium from uranium-containing wastewater, characterized in that: The preparation method comprises the following steps: S1. Preparation of zwitterionic covalent organic framework materials; S2. Obtaining graphene oxide, and performing functionalization treatment on the graphene oxide to obtain functionalized graphene oxide; S3. Add functionalized graphene oxide and zwitterionic covalent organic framework material into deionized water, and vacuum filter on a PES substrate to obtain a graphene oxide composite membrane.
2. The method for preparing a graphene oxide composite membrane for extracting uranium from uranium-containing wastewater according to claim 1, wherein: The preparation of the zwitterionic covalent organic framework material comprises the following steps: S4, adding ethidium bromide and 2,5-diaminobenzenesulfonic acid to a mixed solvent of dioxane and mesitylene and performing ultrasonic dispersion treatment to prepare a first mixture; S5, adding trialdehyde phloroglucinol and glacial acetic acid to the first mixture and performing ultrasonic dispersion treatment to prepare a second mixture; S6, placing the second mixture in liquid nitrogen for a freeze-degassed cycle, and then performing a heat treatment to prepare a third mixture; S7. The third mixture is centrifuged and washed with acetone and ethanol respectively, and then vacuum dried to obtain a zwitterionic covalent organic framework material.
3. The method for preparing a graphene oxide composite membrane for extracting uranium from uranium-containing wastewater according to claim 1, wherein: The functionalization treatment of graphene oxide in step S2 comprises the following steps: S8, placing graphene oxide in deionized water and performing ultrasonic stirring treatment to obtain a graphene oxide solution; S9, adding N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride and N-hydroxysuccinimide to the graphene oxide solution to obtain a modified graphene oxide solution; S10. Adding polyethyleneimine to the modified graphene oxide solution to prepare functionalized graphene oxide.
4. The method for preparing a graphene oxide composite membrane for extracting uranium from uranium-containing wastewater according to claim 1, wherein: In step S3, the mass ratio of the functionalized graphene oxide to the zwitterionic covalent organic framework material is 6:
5.
5. The method for preparing a graphene oxide composite membrane for extracting uranium from uranium-containing wastewater according to claim 2, wherein: The ultrasonic treatment time during the preparation of the first mixture is 20 minutes to 35 minutes, and the ultrasonic treatment time during the preparation of the second mixture is 5 minutes to 15 minutes.
6. The method for preparing a graphene oxide composite membrane for extracting uranium from uranium-containing wastewater according to claim 2, wherein: The temperature for vacuum drying the third mixture is 50° C. to 70° C.
7. A graphene oxide composite membrane for extracting uranium from uranium-containing wastewater, characterized in that: The preparation method is as described in any one of claims 1 to 6.