Reusable strontium recovery material and method of making and use

Abstract

The application belongs to the technical field of strontium recovery materials, and discloses a reusable strontium recovery material, a preparation method and application. The preparation method of the reusable strontium recovery material comprises the following steps: preparing dialdehyde sodium alginate; and mixing and reacting the dialdehyde sodium alginate with collagen fibers, and then washing with water and drying. The strontium recovery material prepared by the application has an extremely fast adsorption rate for Sr 2+ , reaches adsorption equilibrium in 6 min, and can quickly recover Sr 2+ . The strontium recovery material has excellent reusability, and still has an adsorption capacity of about 0.26 mmol g ‑1 -1 after 17 cycles. Moreover, collagen fibers and sodium alginate are both renewable natural biomass materials, and have environmental friendliness. The material prepared by using them has low cost, high economic benefit and great application value.

Description

Technical Field

[0001] This invention relates to the field of strontium recycling materials technology, specifically to reusable strontium recycling materials, their preparation methods, and applications. Background Technology

[0002] The occurrence of a nuclear accident and the subsequent leakage of radioactive nuclides made the handling of radioactive contamination extremely important. However, despite tremendous efforts, the management of nuclear waste remains a challenging problem. 90 Sr is the most common man-made radioactive strontium, produced by... 235 U and 239 Pu is derived from fission, with a fission yield as high as 4.5%. Due to its long half-life (28.9 years), high mobility, and high fission yield, 90 Sr is one of the most widely found radionuclides in nuclear waste and the environment. Radioactivity 90 Sr deposition in human bones can cause serious health problems, including bone cancer, rickets, and leukemia. In contrast, due to its unique chemical reactivity and radioactivity, 90 Sr also has multiple uses, namely as a radiation source for radiotherapy, a heat source for radioisotope thermoelectric generators, and a beta radiation source for radiation measurement and detection. Therefore, considering 90 The environmental hazards and resource advantages of Sr, and its recovery from nuclear waste. 90 Sr is of great significance.

[0003] Currently, most strontium adsorbents are either not reusable or have poor reusability, resulting in low economic efficiency and increased final waste accumulation. Sodium alginate, rich in hydroxyl and carboxyl groups, reacts with Sr... 2+ Plasma exhibits strong affinity. Currently, sodium alginate is typically prepared into alginate microspheres for use with Sr. 2+ Removal. Sodium alginate and Sr in solution. 2+ The reaction is rapid, occurring immediately upon contact; however, the adsorption equilibrium time of the prepared alginate microspheres is relatively slow, requiring 3–6 hours. This may be due to insufficient exposure of the functional groups of the microsphere-shaped alginate, which is unfavorable for Sr. 2+ The combination of factors leads to a slower adsorption rate.

[0004] In view of this, the present invention is proposed. Summary of the Invention

[0005] The purpose of this invention is to solve at least one of the above-mentioned technical problems and to provide a reusable strontium recycling material, its preparation method, and its application.

[0006] To achieve the above objectives, the first technical solution adopted by the present invention is as follows: The method for preparing reusable strontium recycling materials includes the following steps: Preparation of dialdehyde sodium alginate; Sodium dialdehyde alginate was mixed with collagen fibers and reacted, then washed with water and dried.

[0007] Preferably, the method for preparing dialdehyde sodium alginate includes: dissolving sodium alginate and an oxidizing agent in water and oxidizing in the dark for 2-3 hours.

[0008] Preferably, the oxidant is periodate, comprising sodium periodate and potassium periodate.

[0009] Preferably, the mass ratio of the dialdehyde sodium alginate to collagen fibers is (0.5~1.5):1. Preferably, the specific method for mixing and reacting dialdehyde sodium alginate with collagen fibers includes: Sodium dialdehyde alginate was mixed with collagen fibers and stirred for 1-2 hours. The pH of the solution was adjusted to 7.5-8.5, and the temperature was raised to 35-40℃. The reaction was continued for 4-8 hours.

[0010] Preferably, the collagen fibers are pretreated and fully dispersed collagen fibers; the pretreated and fully dispersed collagen fibers include chromium cross-linked collagen fibers, iron cross-linked collagen fibers, titanium cross-linked collagen fibers, and zirconium cross-linked collagen fibers.

[0011] Preferably, the drying temperature is 40~55℃.

[0012] The present invention also discloses reusable strontium recycling materials obtained by any of the preparation methods described above.

[0013] The second technical solution adopted in this invention is: the application of reusable strontium recovery materials in the recovery of radioactive strontium.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The strontium recovery material prepared in this invention is effective against Sr. 2+ The adsorption rate is extremely fast, reaching adsorption equilibrium in 6 minutes, allowing for rapid recovery of Sr. 2+ The strontium recovery material exhibits excellent reusability; after 17 cycles, it still retains 0.26 mmol g. -1 The adsorption capacity is around [value missing]. Furthermore, both collagen fibers and sodium alginate are renewable natural biomass materials, making them environmentally friendly. Materials prepared using them are inexpensive, economically efficient, and have significant application value. Attached Figure Description

[0015] Figure 1 The Zr-CFs-OSA strontium recovery material prepared for Embodiment 3 of this invention is used to recover Sr. 2+ Adsorption kinetics at different adsorption times; Figure 2 The graph shows the reusability of the strontium recovery material Zr-CFs-OSA prepared in Example 3 of this invention after multiple adsorption-desorption cycle experiments. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention. Unless otherwise specified, specific conditions in the embodiments are performed under conventional conditions or conditions recommended by the manufacturer. Reagents or instruments used, unless otherwise specified, are all commercially available conventional products.

[0017] The first embodiment of the present invention provides a method for preparing reusable strontium recycling materials, comprising the following steps: preparing dialdehyde sodium alginate; mixing and reacting dialdehyde sodium alginate with collagen fibers, followed by washing and drying.

[0018] In this embodiment of the invention, two adjacent hydroxyl groups on the sodium alginate unit structure are selectively oxidized by an oxidant to two aldehyde groups. The aldehyde groups of the dialdehyde sodium alginate react with the amino groups of collagen fibers to form a stable covalent bond, making the prepared strontium recycling material structurally stable and exhibiting excellent reusability. Due to the multi-level structure of collagen fibers, the functional groups -COOH of sodium alginate can be fully exposed on the surface of collagen fibers, which is beneficial for reacting with Sr. 2+ The combination of these factors results in a highly rapid adsorption rate of strontium in the prepared recycled material.

[0019] In some preferred embodiments, to further improve the adsorption performance of the strontium recovery material for strontium, the collagen fibers can be pretreated to obtain fully dispersed collagen fibers; the pretreated and fully dispersed collagen fibers include chromium cross-linked collagen fibers, iron cross-linked collagen fibers, titanium cross-linked collagen fibers, and zirconium cross-linked collagen fibers. Because Cr... 3+ Fe 3+ Ti 4+ and Zr 4+ Metal ions exhibit good dispersibility towards collagen fibers, further enhancing their properties and their interaction with Sr. 2+ This enhances the binding capacity of strontium and improves the adsorption rate of strontium.

[0020] The collagen fiber source may include collagen fibers from commonly used animal hides such as pigskin, cowhide, and sheepskin.

[0021] In some specific embodiments, the method for preparing dialdehyde sodium alginate includes: dissolving sodium alginate and an oxidizing agent in water, and then oxidizing in the dark for 2-3 hours. In some preferred embodiments, the oxidizing agent is periodate, comprising sodium periodate and potassium periodate.

[0022] In some preferred embodiments, the mass ratio of the dialdehyde sodium alginate to collagen fibers is (0.5~1.5):1.

[0023] In some specific embodiments, the specific method for mixing sodium dialdehyde aldehyde with collagen fibers includes: mixing and stirring sodium dialdehyde aldehyde with collagen fibers for 1-2 hours, adjusting the pH of the solution to 7.5-8.5, raising the temperature to 35-40°C, and continuing the reaction for 4-8 hours.

[0024] There is no specific limitation on the specific operation of washing and drying after the reaction of sodium dialdehyde aldehyde with collagen fibers. Those skilled in the art can select specific washing and drying methods and parameters according to actual needs. For example, the drying temperature can be 40~55℃.

[0025] To make the technical solution of the present invention clearer, the following detailed description of the strontium recycling material and its application effects of the present invention is provided through several specific embodiments.

[0026] Example 1 Method for preparing reusable strontium recycling materials: Dissolve 0.5 g sodium alginate and 0.5 g potassium periodate in 25 mL of deionized water and oxidize at 30 °C in the dark for 2.5 h. Add 0.5 g collagen fiber and continue stirring for 1 h. Adjust the pH of the solution to 7.5, raise the temperature to 35 °C, and continue the reaction for 4 h. Wash with deionized water and dry at 40 °C to obtain strontium recovery material CFs-OSA.

[0027] The strontium recovery material CFs-OSA prepared in this embodiment was used at a dosage of 1 g / L, and its adsorption capacity for strontium ions at 303 K and 180 rpm was only 0.04 mmol g. -1 .

[0028] Example 2 Method for preparing reusable strontium recycling materials: 1.0 g sodium alginate and 1.0 g sodium periodate were dissolved in 50 mL of deionized water and oxidized at 30 °C in the dark for 2 h. 2 g titanium cross-linked collagen fiber was added and the mixture was stirred for another 1 h. The pH of the solution was adjusted to 8.0, the temperature was raised to 35 °C, and the reaction was continued for another 5 h. The mixture was washed with deionized water and dried at 45 °C to obtain the strontium recovery material Ti-CFs-OSA.

[0029] The strontium recovery material Ti-CFs-OSA prepared in this embodiment has an adsorption capacity of 0.25 mmol g for strontium ions. -1 Compared to Example 1, the adsorption capacity of the adsorbent material prepared from titanium cross-linked collagen fibers is significantly improved.

[0030] Example 3 Method for preparing reusable strontium recycling materials: 2.0 g sodium alginate and 2.0 g sodium periodate were dissolved in 100 mL deionized water and oxidized at 30 °C in the dark for 3 h. 1.5 g zirconium cross-linked collagen fiber was added and stirred for another 2 h. The pH of the solution was adjusted to 8.5, the temperature was raised to 40 °C, and the reaction was continued for another 8 h. The solution was washed with deionized water and dried at 55 °C to obtain the strontium recovery material Zr-CFs-OSA.

[0031] In the process of implementing the present invention, the applicant discovered through multiple experiments that among the various materials prepared in the embodiments of the present invention, the strontium recovery material Zr-CFs-OSA prepared in Example 3 has the highest adsorption capacity for strontium ions. The Zr-CFs-OSA dosage is 1 g / L, and the adsorption capacity for strontium ions at 303 K and 180 rpm is 0.42 mmol g. -1 .

[0032] The Zr-CFs-OSA prepared in this embodiment has an extremely fast adsorption rate, reaching equilibrium in 6 minutes, and can rapidly recover Sr. 2+ ,like Figure 1 As shown in the figure. It also exhibits excellent reusability; after 17 adsorption-desorption cycles, the adsorption capacity remained at 0.26 mmol g. -1 Left and right, such as Figure 2 As shown.

[0033] Figure 1 The adsorption kinetics of Zr-CFs-OSA, a medium-strontium recovery material, at a dosage of 1 g / L, at 303 K and 180 rpm for different adsorption times were investigated. Figure 2 To improve the reusability of the strontium recovery material Zr-CFs-OSA, Zr-CFs-OSA was used at a concentration of 1 g / L. After adsorption at 303 K and 180 rpm for 2 h, it was desorbed and regenerated using cyclohexanediaminetetraacetic acid (CDTA) solution. This cycle was repeated 17 times.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. The application of reusable strontium recovery materials in the recovery of radioactive strontium, characterized in that, The method for preparing reusable strontium recycling materials includes the following steps: Preparation of dialdehyde sodium alginate; Sodium dialdehyde alginate was mixed with collagen fibers and reacted, then washed with water and dried. The collagen fiber is a titanium cross-linked collagen fiber or a zirconium cross-linked collagen fiber.

2. The application as described in claim 1, characterized in that, Methods for preparing dialdehyde sodium alginate include: Sodium alginate and oxidant are dissolved in water and oxidized in the dark for 2-3 hours.

3. The application as described in claim 2, characterized in that, The oxidant is periodate, which includes sodium periodate and potassium periodate.

4. The application as described in claim 1, characterized in that, The mass ratio of sodium dialdehyde aldehyde to collagen fiber is (0.5~1.5):

1.

5. The application as described in claim 1, characterized in that, Specific methods for mixing and reacting sodium dialdehyde aldehyde with collagen fibers include: Sodium dialdehyde alginate was mixed with collagen fibers and stirred for 1-2 hours. The pH of the solution was adjusted to 7.5-8.5, and the temperature was raised to 35-40℃. The reaction was continued for 4-8 hours.

6. The application as described in claim 1, characterized in that, The drying temperature is 40-55℃.

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