A method for preparing an amidoxime modified cellulose-graphite oxide composite uranium adsorbent by irradiation

Abstract

The application discloses a method for preparing an amidoxime modified cellulose-oxidized graphite composite uranium adsorbent by irradiation, and belongs to the field of uranium-containing radioactive wastewater treatment. The present application aims at solving the problems of low grafting rate of the existing cellulose surface, limited number of functional sites for uranium, and uranium adsorption performance to be improved. The method comprises the following steps: 1, preparing acrylonitrile grafted cellulose by irradiation; 2, amidoxime modification; and 3, adding oxidized graphite. The application is used for preparing an amidoxime modified cellulose-oxidized graphite composite uranium adsorbent by irradiation.

Description

Technical Field

[0001] This invention belongs to the field of uranium-containing radioactive wastewater treatment. Background Technology

[0002] Nuclear energy, as a clean and efficient energy source, is the preferred solution for many countries worldwide to address energy shortages. Nuclear heating reactors are a new energy source suitable for large-scale deployment, enabling the gradual replacement of existing heat sources. While ensuring heating safety, they can significantly reduce pollutant emissions, effectively improving the energy structure and achieving the strategic goals of carbon peaking and carbon neutrality. Uranium is a core element in nuclear energy development. Direct discharge of uranium-containing wastewater without treatment will inevitably cause serious harm to the ecological environment. The efficient separation of radioactive uranium is a research hotspot and a pressing challenge in the nuclear fuel cycle field. Developing environmentally friendly and highly efficient uranium adsorbents is therefore crucial. An ideal uranium adsorbent should possess characteristics such as stability, high efficiency, high selectivity, and reusability.

[0003] Cellulose, one of the most abundant natural organic polymers, possesses unique properties such as non-toxicity, renewability, and biodegradability, and has proven to be one of the most promising uranium adsorbents. Currently, cellulose-based uranium adsorbents with different functional ligands, such as amidine oximes, phosphates, carboxyl groups, and amino groups, have been used in the field of uranium adsorption. Among these, amidine oximes have been the most widely reported, as the electron donors in their structure give the adsorbents high chelating affinity and selectivity for uranium ions. However, cellulose exhibits a two-phase structure—crystalline and amorphous—due to the presence of numerous polar hydroxyl groups within and between adjacent molecular chains, forming a large hydrogen bond system. This two-phase structure severely affects the physicochemical properties and reactivity of cellulose. Most reactive monomers can only reach the amorphous region of cellulose and cannot enter the crystalline region. High crystallinity ultimately leads to a low grafting rate on the cellulose surface, limiting the number of functional sites that can interact with uranium, thus hindering further improvements in the uranium adsorption capacity of modified products. Summary of the Invention

[0004] This invention aims to address the problems of low grafting rate on the surface of existing cellulose, limited number of functional sites that interact with uranium, and the need to improve uranium adsorption performance. It provides a method for preparing a cellulose-graphite oxide composite uranium adsorbent modified with a ceramide oxime by irradiation.

[0005] A method for preparing a cellulose-graphite oxide composite uranium adsorbent modified with a ceramide oxime by irradiation comprises the following steps:

[0006] I. Cellulose, acrylonitrile, and glycidyl methacrylate were dispersed in N,N-dimethylformamide to obtain a mixed system. Under irradiation doses of 40 kGy to 100 kGy, [the following was performed]: 60The mixed system was irradiated with Co-γ rays for 4 to 10 hours, then washed and dried to obtain acrylonitrile-grafted cellulose.

[0007] 2. Dissolve hydroxylamine hydrochloride in a methanol / water mixture, then adjust the pH, add acrylonitrile-grafted cellulose to obtain a reaction system, heat the reaction system to react, then cool to room temperature and wash and dry to obtain amine oxime-modified cellulose;

[0008] 3. Dissolve the cellulose modified with oxime in a sodium hydroxide / urea / water system, then add graphite powder, react at room temperature, and then wash and dry to obtain the cellulose-graphite composite uranium adsorbent modified with oxime.

[0009] The beneficial effects of this invention are:

[0010] This invention utilizes irradiation to initiate a grafting reaction between cellulose and acrylonitrile, while simultaneously adjusting the irradiation dose to control the crystallinity of cellulose and enhance its surface modification. To compensate for the structural damage caused by reduced crystallinity, graphene oxide powder is used as a supporting unit to prepare a cellulose-graphene oxide composite uranium adsorbent modified with a methylamine oxime. Due to the synergistic effect of numerous methylamine oxime sites on the surface and the inherent carboxyl groups of graphene oxide, a cellulose-based uranium adsorbent with high adsorption capacity and excellent adsorption selectivity is obtained.

[0011] This invention relates to a method for preparing a uranium adsorbent modified with cellulose-graphite oxide using an irradiation method. Attached Figure Description

[0012] Figure 1 Infrared spectrum of the cellulose-graphite composite uranium adsorbent modified with amine oxime prepared in Example 1;

[0013] Figure 2 The XRD pattern of the cellulose-graphite composite uranium adsorbent modified with amine oxime in Example 1;

[0014] Figure 3 The images show the surface scanning electron microscope (SEM) images and mapping diagrams of the cellulose-graphite composite uranium adsorbent modified with amine oxime prepared in Example 1. (a) and (b) are SEM images, (c) shows C element, (d) shows O element, and (e) shows N element.

[0015] Figure 4 The adsorption performance of the cellulose-graphite composite uranium adsorbent modified with amine oxime prepared in Example 1 at different adsorption times is shown in the figure.

[0016] Figure 5 The adsorption isotherm of the cellulose-amine oxime composite graphite uranium oxide adsorbent prepared in Example 1;

[0017] Figure 6 The graph shows the effect of competing ions on the adsorption effect of the cellulose-amine oxime composite graphite uranium oxide adsorbent prepared in Example 1. 1 represents before adsorption, 2 represents after adsorption, and the line represents the removal capacity.

[0018] Figure 7 The graph shows the trend of crystallinity of acrylonitrile-grafted cellulose prepared in Examples 1 to 4 and Comparative Experiment 1, Step 1, as a function of irradiation dose.

[0019] Figure 8 The graph shows a comparison of the adsorption performance of the cellulose-amine oxime composite graphite uranium oxide adsorbents prepared in Examples 1 to 4 and Comparative Experiment 1.

[0020] Figure 9 The graph shows a comparison of the adsorption performance of the cellulose-amine oxime composite graphite uranium oxide adsorbents prepared in Example 1 and Comparative Experiment 2. Detailed Implementation

[0021] Specific Implementation Method 1: This implementation method discloses a method for preparing a ceramide oxime-modified cellulose-graphite oxide composite uranium adsorbent using an irradiation method, which is carried out according to the following steps:

[0022] I. Cellulose, acrylonitrile, and glycidyl methacrylate were dispersed in N,N-dimethylformamide to obtain a mixed system. Under irradiation doses of 40 kGy to 100 kGy, [the following was performed]: 60 The mixed system was irradiated with Co-γ rays for 4 to 10 hours, then washed and dried to obtain acrylonitrile-grafted cellulose.

[0023] 2. Dissolve hydroxylamine hydrochloride in a methanol / water mixture, then adjust the pH, add acrylonitrile-grafted cellulose to obtain a reaction system, heat the reaction system to react, then cool to room temperature and wash and dry to obtain amine oxime-modified cellulose;

[0024] 3. Dissolve the cellulose modified with oxime in a sodium hydroxide / urea / water system, then add graphite powder, react at room temperature, and then wash and dry to obtain the cellulose-graphite composite uranium adsorbent modified with oxime.

[0025] The beneficial effects of this embodiment are:

[0026] This embodiment utilizes irradiation to initiate a grafting reaction between cellulose and acrylonitrile, while simultaneously adjusting the irradiation dose to control the crystallinity of cellulose and enhance the degree of surface modification. To compensate for the damage to the cellulose structure caused by reduced crystallinity, graphene oxide powder is used as a supporting unit to prepare a cellulose-graphene oxide composite uranium adsorbent modified with a methylamine oxime. Due to the synergistic effect of numerous methylamine oxime sites on the surface and the inherent carboxyl groups of graphene oxide, a cellulose-based uranium adsorbent with high adsorption capacity and excellent adsorption selectivity is obtained.

[0027] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One in that: the mass ratio of cellulose to acrylonitrile in step one is 1g:(10-30)mL; the mass ratio of cellulose to glycidyl methacrylate in step one is 1g:(8-12)mL; and the mass ratio of cellulose to N,N-dimethylformamide in step one is 1g:(60-100)mL. Everything else is the same as in Specific Implementation Method One.

[0028] Specific Implementation Method Three: This implementation method differs from Specific Implementation Method One or Two in that the washing described in step one specifically involves sequentially washing with N,N-dimethylformamide and deionized water. Everything else is the same as in Specific Implementation Method One or Two.

[0029] Specific Implementation Method Four: This implementation method differs from Specific Implementation Methods One to Three in that: the mass ratio of hydroxylamine hydrochloride to the volume ratio of the methanol / water mixed solution in step two is 1 g:(20-30) mL; the mass ratio of hydroxylamine hydrochloride to acrylonitrile-grafted cellulose in step two is 1:(0.05-0.15). Everything else is the same as in Specific Implementation Methods One to Three.

[0030] Specific Implementation Method Five: This implementation method differs from Specific Implementation Methods One to Four in that the volume ratio of methanol to water in the methanol / water mixed solution described in step two is 1:(0.5~1.5). Everything else is the same as in Specific Implementation Methods One to Four.

[0031] Specific Implementation Method Six: This implementation method differs from Specific Implementation Methods One to Five in that: in step two, sodium hydroxide is used to adjust the pH to 5.5–7.5. Everything else is the same as Specific Implementation Methods One to Five.

[0032] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Methods One to Six in that: in step two, the reaction system is heated to a temperature of 60℃~80℃, and the reaction is carried out for 4h~6h at this temperature. Everything else is the same as in Specific Implementation Methods One to Six.

[0033] Specific Implementation Method Eight: This implementation method differs from Specific Implementation Methods One to Seven in that: the mass ratio of the methylamine oxime-modified cellulose to graphite oxide powder in step three is 1:(0.4-0.8); the mass ratio of the methylamine oxime-modified cellulose to the volume ratio of the sodium hydroxide / urea / water system in step three is 1g:(80-120)mL. Everything else is the same as in Specific Implementation Methods One to Seven.

[0034] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Methods One to Eight in that: in the sodium hydroxide / urea / water system described in step three, the mass ratio of sodium hydroxide to urea is 1:(1.3-2.1), and the mass ratio of sodium hydroxide to water is 1g:(10-12)mL. Everything else is the same as in Specific Implementation Methods One to Eight.

[0035] Specific Implementation Method Ten: This implementation method differs from Specific Implementation Methods One to Nine in that the reaction in step three is carried out at room temperature for 36 to 54 hours. Everything else is the same as in Specific Implementation Methods One to Nine.

[0036] The beneficial effects of the present invention are verified using the following embodiments:

[0037] Example 1:

[0038] A method for preparing a cellulose-graphite oxide composite uranium adsorbent modified with a ceramide oxime by irradiation, characterized by the following steps:

[0039] 1. Disperse 0.5g cellulose, 10mL acrylonitrile, and 5mL glycidyl methacrylate in 40mL N,N-dimethylformamide to obtain a mixed system. Under an irradiation dose of 80kGy, use... 60 The mixed system was irradiated with Co-γ rays for 8 hours, then washed and dried with N,N-dimethylformamide and deionized water to obtain acrylonitrile-grafted cellulose.

[0040] 2. Dissolve 4g of hydroxylamine hydrochloride in 100mL of methanol / water mixed solution, then adjust the pH to 6.5 with sodium hydroxide, and add 0.4g of acrylonitrile-grafted cellulose to obtain the reaction system. Heat the reaction system to 70℃ and react at 70℃ for 4h. Then cool to room temperature and wash with deionized water until neutral. Finally dry to obtain amine oxime modified cellulose.

[0041] 3. Dissolve 0.2g of amylopectin-modified cellulose in 20mL of sodium hydroxide / urea / water system, then add 0.12g of graphite oxide powder, react at room temperature for 48h, then wash with deionized water until neutral, and finally freeze-dry at -55℃ for 24h to obtain amylopectin-modified cellulose-graphite oxide composite uranium adsorbent.

[0042] In step two, the volume ratio of methanol to water in the methanol / water mixed solution is 1:1.

[0043] In the sodium hydroxide / urea / water system described in step three, the mass ratio of sodium hydroxide to urea is 1:1.7, and the mass ratio of sodium hydroxide to water is 1g:11.6mL.

[0044] Figure 1The infrared spectrum of the cellulose-graphite composite uranium adsorbent modified with amine oxime prepared in Example 1; in the uranium adsorbent, in addition to the characteristic peak of cellulose, there is a peak at 2242 cm⁻¹. -1 The C≡N peak disappears at 1557 cm⁻¹ -1 The newly added peak at the C=N double bond indicates that the cyano group was successfully metamidicized, and the peak was observed at 1617 cm⁻¹. -1 sp is displayed here 2 The C=C tensile vibration peak of the carbon-arranged graphene sheet indicates that cellulose successfully reacted with graphene oxide.

[0045] Figure 2 The XRD pattern of the cellulose-graphite oxide composite uranium adsorbent modified with a methylamine oxime is shown in Example 1. The cellulose-methylamine oxime composite uranium oxide adsorbent exhibits characteristic peaks very similar to those of cellulose, indicating that amide oximeation does not destroy the crystal structure of cellulose. In the cellulose-methylamine oxime composite uranium oxide adsorbent, a new sharp peak belonging to the (001) plane of graphene oxide was found at 2θ at 11.6°.

[0046] Figure 3 The images show the surface scanning electron microscope (SEM) images and mapping diagrams of the cellulose-graphite oxide composite uranium adsorbent modified with a cellulose amylopectin (CA) prepared in Example 1. (a) and (b) are SEM images, (c) shows carbon (C), (d) shows oxygen (O), and (e) shows nitrogen (N). The SEM images reveal a typical wrinkled, layered planar structure of graphite oxide. After reacting with cellulose CA, the surface of the cellulose CA-CA composite uranium oxide adsorbent is relatively smooth with fewer wrinkles. The mapping diagrams demonstrate that, in addition to C and O, nitrogen (N) is also uniformly distributed on the surface of the cellulose CA-CA composite uranium oxide adsorbent. This further confirms that the cellulose CA-CA composite uranium oxide adsorbent is uniformly deposited on the GO surface.

[0047] Uranium adsorption test: Uranyl nitrate hexahydrate (UO2(NO3)2·6H2O) aqueous solution was used to simulate actual uranium-containing nuclear waste liquid, denoted as U(VI). 2.1092 g of UO2(NO3)2·6H2O was accurately weighed and dissolved in ultrapure water, then transferred to a 1 L volumetric flask and diluted to volume to obtain a 1000 mg / L uranium solution. In subsequent performance testing experiments, uranium solutions of different concentration gradients were all obtained by diluting the 1000 mg / L high-concentration uranium solution. The concentration of the uranium solution was quantitatively analyzed using a UV-Vis spectrophotometer. Azoarsine(III) was used as a chromogenic agent to chelate with U(VI), exhibiting a characteristic absorption peak at a fixed wavelength of 652 nm. Within a certain concentration range, the concentration of U(VI) in the solution showed a linear relationship with the absorbance measured by the UV-Vis spectrophotometer.

[0048] Take 20 mL of a 100 mg / L uranium solution, adjust the pH to 5.0 with NaOH or dilute HNO3 solution, then add 10 mg of the uranium adsorbent modified with cellulose-graphite oxide prepared in Example 1, and shake in a constant temperature water bath at 298 K. After adsorption for a period of time, centrifuge to separate the supernatant, and determine and calculate the uranium ion concentration using a UV spectrophotometer to obtain the adsorption data. Figure 4 The graph shows the adsorption performance of the cellulose-graphite composite uranium adsorbent modified with amine oxime prepared in Example 1 at different adsorption times. The results show that the adsorption of uranium by the adsorbent in Example 1 is a rapid process, with a removal rate of 90% achieved in 1 minute.

[0049] Take 20 mL of a 100 mg / L uranium solution, adjust the pH to 5.0 with NaOH or dilute HNO3 solution, then add 10 mg of the uranium ion-modified cellulose-graphite oxide composite adsorbent prepared in Example 1, and shake in a constant temperature water bath at 298 K. After adsorption for 12 h, centrifuge to separate the supernatant, and determine and calculate the uranium ion concentration using a UV spectrophotometer to obtain the adsorption data. Dry the centrifuged product in a 60 °C oven for 24 h, then add 20 mL of a 0.5 mol / L sodium carbonate desorbent solution, shake in a constant temperature water bath at 298 K, and centrifuge after desorption for 6 h to obtain the desorbed adsorbent. Repeat the above adsorption-desorption process 8 times with the uranium ion-modified cellulose-graphite oxide composite adsorbent prepared in Example 1. The uranium removal rate of the cellulose-graphite oxide composite uranium adsorbent modified with amine oxime prepared in Example 1 was still 85.2% after 8 adsorption-desorption cycles, demonstrating its ability to be recycled.

[0050] 20 mL of uranium solutions with concentrations of 50 mg / L, 80 mg / L, 100 mg / L, 125 mg / L, 142.9 mg / L, 166.7 mg / L, 200 mg / L, 250 mg / L, 333.33 mg / L, 400 mg / L, and 500 mg / L were taken respectively. The pH of the solutions was adjusted to 5.0 with NaOH or dilute HNO3 solution. Then, 10 mg of the amine oxime-modified cellulose-graphite oxide composite uranium adsorbent prepared in Example 1 was added, and the solutions were shaken in a constant temperature water bath at 298 K. After adsorption for 12 h, the supernatant was separated by centrifugation, and the uranium ion concentration was measured and calculated using a UV spectrophotometer to obtain the adsorption data. Figure 5 The adsorption isotherm of the cellulose-amine oxime composite graphite uranium oxide adsorbent prepared in Example 1 is shown; the saturated adsorption capacity of the adsorbent in a 100 mg / L uranium solution is 190.7 mg / g. Fitting the isotherm to the Langumir model yields a maximum adsorption capacity of 237.5 mg / g, indicating a very high adsorption capacity.

[0051] Select Ca 2+ Ni 2+ Cu 2+ K + Mg 2+ Na + A salt solution is mixed with a uranium solution to obtain a mixed solution, in which Ca is present. 2+ Ni 2+ Cu 2+ K + Mg 2+ Na + The initial concentrations of U(VI) were 92 mg / L, 93 mg / L, 97 mg / L, 102 mg / L, 99 mg / L, 94 mg / L, and 98 mg / L, respectively. The pH of the solution was adjusted to 5.0. 20 mL of the above solution was transferred, and 10 mg of the uranium-amine oxime-modified cellulose-graphite composite adsorbent prepared in Example 1 was added. The solution was then shaken in a constant temperature water bath at 298 K. After adsorption for 12 h, the supernatant was separated by centrifugation. The concentrations of uranium and other metal cations in the solution were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Figure 6 The graph shows the effect of competing ions on the adsorption effect of the cellulose-amine oxime composite graphite uranium adsorbent prepared in Example 1. 1 represents before adsorption, 2 represents after adsorption, and the line represents the removal capacity. As shown in the graph, among the many ions, the material still has an adsorption capacity of 124.0 mg / g for uranium.

[0052] Example 2: This example differs from Example 1 in that the irradiation dose in step one is different, set to 40 kGy. Everything else is the same as in Example 1.

[0053] Example 3: This example differs from Example 1 in that the irradiation dose in step one is different, set to 60 kGy. Everything else is the same as in Example 1.

[0054] Example 4: This example differs from Example 1 in that the irradiation dose in step one is different, set to 100 kGy. Everything else is the same as Example 1.

[0055] Comparative Experiment 1: This comparative experiment differs from Example 1 in that the irradiation dose in step one is different, set at 20 kGy. Everything else is the same as in Example 1.

[0056] Comparative Experiment 2: This comparative experiment differs from Example 1 in that: in step one, 0.5g cellulose, 10mL acrylonitrile, 5mL glycidyl methacrylate, and 0.5g potassium persulfate initiator were dispersed in 40mL N,N-dimethylformamide to obtain a mixed system. The mixed system was heated to 70℃ and reacted at 70℃ for 30min to obtain acrylonitrile-grafted cellulose. Everything else was the same as in Example 1.

[0057] Figure 7 The graph shows the trend of crystallinity of acrylonitrile-grafted cellulose prepared in Examples 1 to 4 and Comparative Experiment 1 Step 1 as a function of irradiation dose. As can be seen from the graph, the crystallinity of acrylonitrile-grafted cellulose gradually decreases with increasing irradiation dose, indicating that the crystallinity of cellulose can be effectively controlled by adjusting the irradiation dose.

[0058] The nitrogen content of acrylonitrile-grafted cellulose prepared in Examples 1 to 3 and Comparative Experiment 1, Step 1 was tested using an organic elemental analyzer. The degree of substitution of acrylonitrile-grafted cellulose was calculated from the nitrogen content. When the irradiation dose was 0, 20, 40, 60, and 80 kGy, the degree of substitution of acrylonitrile-grafted cellulose was 0, 0.38, 0.43, 0.47, and 0.51, respectively. The increase in irradiation dose reduced the crystallinity of cellulose and improved the surface modification of cellulose.

[0059] Take 20 mL of uranium solution with a concentration of 100 mg / L, adjust the pH to 5.0 with NaOH or dilute HNO3 solution, then add 10 mg of the cellulose-amine oxime composite graphite uranium adsorbent prepared in Examples 1 to 4 and Comparative Experiment 1, and then shake in a constant temperature water bath at 298 K. After adsorption for 12 h, centrifuge to separate the supernatant, and use a UV spectrophotometer to determine and calculate the uranium ion concentration to obtain the adsorption data. Figure 8 The graph shows a comparison of the adsorption performance of the cellulose-amine oxime composite graphite uranium oxide adsorbents prepared in Examples 1 to 4 and Comparative Experiment 1. The results show that the saturated adsorption capacity of the prepared adsorbents is 142.8 mg / g (Comparative Experiment 1), 156.3 mg / g (Example 2), 167.8 mg / g (Example 3), and 181.3 mg / g (Example 4), which is lower than that of the adsorbent obtained in Example 1.

[0060] Take 20 mL of uranium solution with a concentration of 100 mg / L, adjust the pH to 5.0 with NaOH or dilute HNO3 solution, then add 10 mg of the cellulose-amine oxime composite graphite uranium adsorbent prepared in Example 1 and Comparative Experiment 2, and then shake in a constant temperature water bath at 298 K. After adsorption for 12 h, centrifuge to separate the supernatant, and use a UV spectrophotometer to determine and calculate the uranium ion concentration to obtain the adsorption data. Figure 9 The graph shows a comparison of the adsorption performance of the cellulose-amine oxime composite graphite uranium oxide adsorbents prepared in Example 1 and Comparative Experiment 2. The results show that the saturated adsorption capacity of the adsorbent prepared in Comparative Experiment 2 is 79.1 mg / g, which is lower than that of the adsorbent obtained in Example 1.

Claims

1. A method for preparing a cellulosic-oxidized graphite composite uranium adsorbent modified with amidoxime by irradiation, characterized by It is done in the following steps: I. Cellulose, acrylonitrile, and glycidyl methacrylate were dispersed in N,N-dimethylformamide to obtain a mixed system. Under irradiation doses of 80 kGy to 100 kGy, [the following was used]... 60 The mixed system was irradiated with Co-γ rays for 4-10 hours, then washed and dried to obtain acrylonitrile-grafted cellulose. The mass ratio of cellulose to acrylonitrile is 1g:(10~30)mL; the mass ratio of cellulose to glycidyl methacrylate is 1g:(8~12)mL; the mass ratio of cellulose to N,N-dimethylformamide is 1g:(60~100)mL.

2. Dissolve hydroxylamine hydrochloride in a methanol / water mixture, then adjust the pH to 5.5~7.5, and add acrylonitrile-grafted cellulose to obtain a reaction system. Heat the reaction system to 60℃~70℃ and react for 4h~6h at 60℃~70℃. Then cool to room temperature, wash and dry to obtain amine oxime-modified cellulose. The mass ratio of hydroxylamine hydrochloride to the volume ratio of the methanol / water mixed solution is 1 g:(20~30) mL; the mass ratio of hydroxylamine hydrochloride to acrylonitrile-grafted cellulose is 1:(0.05~0.15); and the volume ratio of methanol to water in the methanol / water mixed solution is 1:(0.5~1.5).

3. Dissolve the cellulose modified with oxime in a sodium hydroxide / urea / water system, then add graphite powder, react at room temperature for 36-54 hours, then wash and dry to obtain the cellulose-graphite composite uranium adsorbent modified with oxime. The mass ratio of the modified cellulose to graphite powder is 1:(0.4~0.8); the mass ratio of the modified cellulose to the volume ratio of the sodium hydroxide / urea / water system is 1g:(80~120)mL. In the sodium hydroxide / urea / water system, the mass ratio of sodium hydroxide to urea is 1:(1.3~2.1), and the mass ratio of sodium hydroxide to water is 1g:(10~12)mL.

2. The method for preparing the amidoxime modified cellulose-graphene oxide composite uranium adsorbent by irradiation method according to claim 1, characterized in that The washing process described in step one specifically involves washing with N,N-dimethylformamide and deionized water in sequence.

3. The method for preparing a cellulose-graphite oxide composite uranium adsorbent modified with a ceramide oxime by irradiation according to claim 1, characterized in that... In step two, sodium hydroxide is used to adjust the pH to 5.5-7.5.

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