Iodate adsorbing material as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of adsorption materials, and particularly relates to an iodate adsorption material as well as a preparation method and application thereof. The iodate adsorbing material is Zr < 4 + >-loaded collagenous fiber. The preparation method comprises the following steps: soaking collagenous fibers in a NaCl solution for 6-12 hours, adding a Zr < 4 + > solution, uniformly mixing, reacting, filtering, washing and drying. The Zr-CFs has the advantages of large adsorption capacity and fast adsorption rate for iodate radicals, and has good adsorption selectivity and irradiation stability. According to the adsorbing material obtained by the invention, Zr < 4 + > is stably immobilized on the collagenous fiber, Zr < 4 + > is stably combined with carboxyl and amino on the collagenous fiber, Zr < 4 + > is not leached when the pH value is in a range of 2-11, and the adsorbing material has good acid-base stability and can be used for a long time under acidic and alkaline conditions.

Description

Technical Field

[0001] The present invention belongs to the technical field of adsorption materials, and in particular relates to an iodate adsorption material, a preparation method and an application thereof. Background Art

[0002] As an important clean energy in the 21st century, nuclear energy plays a key role in the global energy structure adjustment and carbon emission reduction strategy. With the large-scale construction and operation of nuclear power plants, the problem of radioactive wastewater treatment has become increasingly prominent. Among them, radioactive iodine ( 129 I and 131 I) is the most challenging to treat due to its special physical and chemical properties: first, iodine has significant environmental mobility and can diffuse widely through the water circulation system; second, iodide ions (I⁻) and iodates (IO3⁻) are highly soluble in water; more importantly, radioactive iodine is easily enriched in organisms and has a specific damaging effect on thyroid tissue.

[0003] In the field of radioactive wastewater treatment, iodine removal technology faces the following key scientific issues: (1) the diversity of iodine chemical forms, of which iodide ion (I⁻) and iodate (IO3⁻) are the two most common forms; (2) the removal mechanisms of different iodine forms vary significantly. Currently, silver-based adsorbents widely used in industry (such as AgX zeolite and silver-loaded activated carbon) show excellent selectivity for I⁻, which is attributed to the extremely low solubility product of AgI (Ksp=8.3×10⁻¹). 7 However, the removal efficiency of IO3⁻ by this material is limited due to the solubility of AgIO3 (Ksp=3.1×10⁻ 8 ) is relatively high, making it difficult to achieve deep purification.

[0004] According to the theory of hard and soft acids and bases, IO⁻⁻ is a typical hard base, capable of forming strong Coulombic interactions with small, high-valence hard acid metal cations, leading to their adsorption. However, these metal ions are prone to hydrolysis in aqueous solutions, forming hydroxyl complexes and even precipitation, making them unsuitable for direct use as water treatment agents. This contradiction raises a key technical challenge: how to construct a stable carrier-metal ion composite system that both preserves the active sites of the hard acid metal ions and prevents their hydrolysis and inactivation.

[0005] In view of this, the present invention is proposed. Summary of the Invention

[0006] The present invention aims to solve the problems existing in the prior art and provides an iodate adsorption material, a preparation method and an application thereof.

[0007] In order to achieve the above object, the first technical solution adopted by the present invention is: Iodate adsorption material, loaded with Zr4+ of collagen fibers.

[0008] Preferably, Zr per gram of iodate adsorption material 4+ The loading amount is 0.121~0.222 g.

[0009] The second technical solution adopted in the present invention is: The preparation method of iodate adsorption material comprises: soaking collagen fibers in NaCl solution for 6 to 12 hours, adding Zr 4+ The solutions are mixed evenly to react, and then filtered, washed and dried.

[0010] It should be noted that the present invention uses NaCl solution to soak collagen fibers to expand the gap between collagen fibers, which is convenient for subsequent Zr 4+ Deep penetration combination.

[0011] Preferably, when the collagen fibers are immersed in the NaCl solution, the pH of the system is adjusted to 1.7-2.0. By adjusting the pH of the system to 1.7-2.0, the carboxyl groups on the collagen fibers can be blocked so that the carboxyl groups do not react with Zr in the initial stage of the reaction. 4+ combination.

[0012] Preferably, Zr 4+ The sources include any one of zirconium sulfate, zirconium chloride, zirconium nitrate, zirconium oxychloride, and zirconium citrate.

[0013] Preferably, after drying, the content of Zr in each gram of iodate adsorption material is 4+ The loading amount is 0.121~0.222 g.

[0014] Preferably, Zr is added 4+ The specific method for mixing the solution uniformly to react is: adding Zr 4+ After the solution is dissolved, stir at 25℃ for 4~6 hours, adjust the pH to 3.5~4.5, react at 40~55℃ for 4~6 hours and then overnight. During this reaction process, by slowly increasing the pH of the system, Zr 4+ It forms a stable bond with the carboxyl and amino groups on collagen fibers.

[0015] The third technical solution adopted by the present invention is; Use of the iodate adsorption material as described in any one of the first technical solutions or the iodate adsorption material obtained by the preparation method as described in any one of the second technical solutions in removing iodate from radioactive wastewater.

[0016] Preferably, a continuous column adsorption device is used. The schematic diagram of the column adsorption device used in the present invention is as follows: Figure 1 shown.

[0017] The beneficial effects of the present invention are: (1) The adsorption material obtained by the present invention retains the multi-level fibrous structure of collagen fibers and has good hydrophilicity, which gives it a fast adsorption rate and low bed resistance. It is suitable for column adsorption devices to treat radioactive wastewater, with a fast adsorption rate and a large treatment capacity.

[0018] (2) The adsorption material obtained by the present invention is Zr 4+ Stably immobilized on collagen fibers, Zr 4+ It forms a stable bond with the carboxyl (-COOH) and amino (-NH2) groups on the collagen fibers. In the pH range of 2 to 11, Zr 4+ There is no leaching, and it has good acid and alkali stability, and can be used for a long time under acidic and alkaline conditions.

[0019] (3) The adsorption material obtained by the present invention has a large amount of Zr 4+ The coordinated hydroxide and iodate can react with Zr 4+ The coordinated hydroxide undergoes ion exchange, thereby adsorbing iodate.

[0020] (4) The adsorption material obtained by the present invention retains the bound water contained in the collagen fibers themselves, which helps to quickly transfer the radiation energy to the environmental medium, thereby giving it higher radiation stability and being suitable for the treatment of radioactive wastewater.

[0021] (5) The preparation process of the present invention is simple, the reaction conditions are mild, it is easy to operate and control, and it is easy to industrialize production.

[0022] (6) The column adsorption device provided by the present invention is suitable for removing iodate from radioactive wastewater in a closed system. Its main advantages include easy operation, small size, and low risk of radiation leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of a column adsorption device provided by the present invention; Figure 2 Collagen fiber CFs (a) and Zr loaded in Example 3 of the present invention 4+ Scanning electron microscopy image of collagen fiber Zr-CFs-3 (b); EDS distribution of different elements (C, N, O, Zr) in Zr-CFs-3 (c) and different elements (C, N, O, Zr, I) in Zr-CFs-I (d) after adsorption of iodate; Figure 3 Collagen fiber CFs and Zr-loaded prepared by the present invention 4+ IR spectrum of collagen fiber Zr-CFs-3; Figure 4 The loaded Zr prepared by the present invention 4+Effect of collagen fiber Zr-CFs-3 on IO3 at different pH - Graph showing the effect of adsorption capacity; Figure 5 The loaded Zr prepared by the present invention 4+ Collagen fiber Zr-CFs-3 to IO3 - Adsorption kinetics curve of Figure 6 The loaded Zr prepared by the present invention 4+ Collagen fiber Zr-CFs-3 to IO3 - Adsorption isotherm curve of ; Figure 7 The loaded Zr prepared by the present invention 4+ The collagen fibers Zr-CFs-3 60 Plot of adsorption capacity after different doses of Co γ-ray irradiation; Figure 8 The loaded Zr prepared by the present invention 4+ Collagen fiber Zr-CFs-3 to IO3 - Adsorption breakthrough curve during continuous column adsorption. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments.It should be understood that these descriptions are exemplary only, and are not intended to limit the scope of the present invention.In addition, in the following description, the description of known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.Unindicated specific conditions in the embodiment are carried out according to the conditions of normal conditions or manufacturer's advice.Reagents used or instruments are not indicated by manufacturers, and are conventional products that can be obtained by commercial purchase.

[0025] Example 1 The preparation method of the iodate adsorption material comprises the following steps: 2.0 g of collagen fibers were soaked in 20 mL of 3% NaCl solution (pH adjusted to 1.7-2.0) for 12 h to obtain a collagen fiber soaking solution for use; 2.0 g of zirconium sulfate was dissolved in 40 mL of deionized water and added to the collagen fiber soaking solution and stirred for 6 h. The pH was adjusted to 4.0-4.5 within 2 h and then heated to 40 °C. After reacting for 4 h, it was allowed to react overnight. The next day, it was filtered, washed, and dried to obtain the loaded Zr 4+ of collagen fibers (Zr-CFs-1).

[0026] The Zr of the obtained Zr-CFs-1 4+The loading amount is 0.124 g / g. When Zr-CFs-1 is 0.05 g, the temperature is 25℃, pH=7, and the adsorption time is 12 h, IO3 - When the concentration of Zr-CFs-1 is 100.0 mg / L, the effect of Zr-CFs-1 on IO3 - The adsorption capacity is 22.58 mg / g.

[0027] Example 2 The preparation method of the iodate adsorption material comprises the following steps: 2.0 g of collagen fibers were soaked in 20 mL of 3% NaCl solution (pH adjusted to 1.7-2.0) for 12 h to obtain a collagen fiber soaking solution for use; 4.0 g of zirconium sulfate was dissolved in 40 mL of deionized water and added to the collagen fiber soaking solution and stirred for 6 h. The pH was adjusted to 4.0-4.5 within 2 h and then heated to 40 °C. After reacting for 4 h, it was allowed to react overnight. The next day, it was filtered, washed, and dried to obtain the loaded Zr 4+ of collagen fibers (Zr-CFs-2).

[0028] The Zr of the obtained Zr-CFs-2 4+ The loading amount is 0.195 g / g. When Zr-CFs-2 is 0.05 g, the temperature is 25℃, pH=7, and the adsorption time is 12 h, IO3 - When the concentration of Zr-CFs-2 is 100.0 mg / L, the effect of Zr-CFs-2 on IO3 - The adsorption capacity is 33.91 mg / g.

[0029] Example 3 The preparation method of the iodate adsorption material comprises the following steps: 2.0 g of collagen fibers were soaked in 20 mL of 3% NaCl solution (pH adjusted to 1.7-2.0) for 12 h to obtain a collagen fiber soaking solution for use; 6.0 g of zirconium sulfate was dissolved in 40 mL of deionized water and added to the collagen fiber soaking solution and stirred for 6 h. The pH was adjusted to 4.0-4.5 within 2 h, and then the temperature was raised to 40 ° C. After reacting for 4 h, it was allowed to react overnight. The next day, it was filtered, washed, and dried to obtain the loaded Zr 4+ of collagen fibers (Zr-CFs-3).

[0030] The Zr of the obtained Zr-CFs-3 4+ The loading amount is 0.222 g / g. When Zr-CFs-3 is 0.05 g, the temperature is 25℃, pH=7, and the adsorption time is 12 h, IO3 - When the concentration of Zr-CFs-3 is 100.0 mg / L, the effect of Zr-CFs-3 on IO3 - The adsorption capacity is 41.98 mg / g.

[0031] The collagen fibers CFs used in this example and the Zr-loaded 4+ The scanning electron microscopy images of collagen fibers (Zr-CFs-3) are shown in Figure 2. Figure 2 As shown in (a) and (b), it can be seen from the figure that Zr-CFs-3 retains the multi-level fibrous structure of CFs. The EDS distribution of different elements (C, N, O, Zr) of Zr-CFs-3 prepared in this example and the different elements (C, N, O, Zr, I) of Zr-CFs-I (d) after adsorption of iodate are shown as follows Figure 2 As shown in (c) and (d), it can be seen from the figure that Zr in Zr-CFs-3 is evenly distributed along the fiber, indicating that Zr 4+ Successfully loaded on CFs; I in Zr-CFs-I is evenly distributed along the fiber, indicating that IO3 - Successful adsorption.

[0032] The Zr-CFs-3 obtained in the embodiment was used for batch adsorption experiments. - The effect of solution pH and adsorption time on the adsorption of IO3 by Zr-CFs-3 was investigated at a concentration of 100.0 mg / L. - The impact of Figure 4 It can be seen that in the range of pH 3 to 11, Zr-CFs-3 has a significant effect on IO3 - The adsorption capacity of Zr-CFs-3 is not much different, indicating that Zr-CFs-3 is suitable for IO3 in various water bodies. - Adsorption of Figure 5 It can be seen that Zr-CFs-3 has a great influence on IO3 - The adsorption rate was extremely fast, reaching 80.87% of the maximum adsorption capacity in 10 min and reaching adsorption equilibrium in 30 min. - The initial concentration of IO3 was 100.0~1100.0 mg / L to explore the effect of initial concentration on IO3 - The adsorption capacity is affected by Figure 6 It can be seen that when IO3 - When the initial concentration is 1100.0 mg / L, at 25℃, the effect of Zr-CFs-3 on IO3 - The adsorption capacity is as high as 134.13 mg / g. - The effect of irradiation dose on the adsorption of IO3 by Zr-CFs-3 was investigated under the conditions of 100.0 mg / L and solution pH=7.0. - The impact of Figure 7 It can be seen that Zr-CFs-3 has a high 60After Co γ-ray irradiation, the adsorption capacity did not decrease significantly, indicating that Zr-CFs-3 has good irradiation stability. 2.0 g Zr-CFs-3 was loaded into a chromatographic column with an inner diameter of 1.0 cm to obtain an adsorption column with a column height of 11.0 cm and used to contain IO3 - Wastewater treatment. Figure 8 It can be seen that Zr-CFs-3 has a great influence on IO3 - It exhibits good dynamic adsorption performance, with a breakthrough point of approximately 189 BV.

[0033] Example 4 The preparation method of the adsorption material of iodate radical comprises the following steps: 2.0 g of collagen fibers were soaked in 20 mL of 3% NaCl solution (pH adjusted to 1.7-2.0) for 12 h to obtain a collagen fiber soaking solution for use; 1.13 g of zirconium chloride was dissolved in 40 mL of deionized water and added to the collagen fiber soaking solution and stirred for 6 h. The pH was adjusted to 4.0-4.5 within 2 h and then heated to 40 °C. After reacting for 4 h, it was allowed to react overnight. The next day, it was filtered, washed, and dried to obtain the loaded Zr 4+ of collagen fibers (Zr-CFs-4).

[0034] The Zr of the obtained Zr-CFs-4 4+ The loading amount is 0.121 g / g. When Zr-CFs-4 is 0.05 g, the temperature is 25℃, pH=7, and the adsorption time is 12 h, IO3 - When the concentration of Zr-CFs-4 is 100.0 mg / L, the effect of Zr-CFs-4 on IO3 - The adsorption capacity is 17.38 mg / g.

[0035] Example 5 The preparation method of the iodate adsorption material comprises the following steps: 2.0 g of collagen fibers were soaked in 20 mL of 3% NaCl solution (pH adjusted to 1.7-2.0) for 12 h to obtain a collagen fiber soaking solution for use; 2.27 g of zirconium chloride was dissolved in 40 mL of deionized water and added to the collagen fiber soaking solution and stirred for 6 h. The pH was adjusted to 4.0-4.5 within 2 h, and then the temperature was raised to 40 ° C. After reacting for 4 h, it was allowed to react overnight. The next day, it was filtered, washed, and dried to obtain the loaded Zr 4+ of collagen fibers (Zr-CFs-5).

[0036] The Zr of the obtained Zr-CFs-5 4+ The loading amount is 0.192 g / g. When Zr-CFs-5 is 0.05 g, the temperature is 25℃, pH=7, and the adsorption time is 12 h, IO3 -When the concentration of Zr-CFs-5 is 100.0 mg / L, the effect of Zr-CFs-5 on IO3 - The adsorption capacity is 27.81 mg / g.

[0037] Example 6 The preparation method of the adsorption material of iodate radical comprises the following steps: 2.0 g of collagen fibers were soaked in 20 mL of 3% NaCl solution (pH adjusted to 1.7-2.0) for 12 h to obtain a collagen fiber soaking solution for use; 3.40 g of zirconium chloride was dissolved in 40 mL of deionized water and added to the collagen fiber soaking solution and stirred for 6 h. The pH was adjusted to 4.0-4.5 within 2 h and then heated to 40 °C. After reacting for 4 h, it was allowed to react overnight. The next day, it was filtered, washed, and dried to obtain the loaded Zr 4+ of collagen fibers (Zr-CFs-6).

[0038] The Zr of the obtained Zr-CFs-6 4+ The loading amount is 0.207 g / g. When Zr-CFs-5 is 0.05 g, the temperature is 25℃, pH=7, and the adsorption time is 12 h, IO3 - When the concentration of Zr-CFs-5 is 100.0 mg / L, the effect of Zr-CFs-5 on IO3 - The adsorption capacity is 45.44 mg / g.

[0039] Example 7 The preparation method of the iodate adsorption material comprises the following steps: 2.0 g of collagen fibers were soaked in 20 mL of 3% NaCl solution (pH adjusted to 1.7-2.0) for 12 h to obtain a collagen fiber soaking solution for use; 2.10 g of zirconium nitrate was dissolved in 40 mL of deionized water and added to the collagen fiber soaking solution and stirred for 6 h. The pH was adjusted to 4.0-4.5 within 2 h and then heated to 40 °C. After reacting for 4 h and overnight, the loaded Zr was filtered, washed, and dried the next day. 4+ of collagen fibers (Zr-CFs-7).

[0040] The Zr of the obtained Zr-CFs-7 4+ The loading amount is 0.137 g / g. When Zr-CFs-5 is 0.05 g, the temperature is 25℃, pH=7, and the adsorption time is 12 h, IO3 - When the concentration of Zr-CFs-5 is 100.0 mg / L, the effect of Zr-CFs-5 on IO3 - The adsorption capacity is 39.42 mg / g.

[0041] Example 8 The preparation method of the iodate adsorption material comprises the following steps: 2.0 g of collagen fibers were soaked in 20 mL of 3% NaCl solution (pH adjusted to 1.7-2.0) for 12 h to obtain a collagen fiber soaking solution for use; 4.18 g of zirconium nitrate was dissolved in 40 mL of deionized water and added to the collagen fiber soaking solution and stirred for 6 h. The pH was adjusted to 4.0-4.5 within 2 h and then heated to 40 °C. After reacting for 4 h, it was allowed to react overnight. The next day, it was filtered, washed, and dried to obtain the loaded Zr 4+ of collagen fibers (Zr-CFs-8).

[0042] The Zr of the obtained Zr-CFs-8 4+ The loading amount is 0.186 g / g. When Zr-CFs-5 is 0.05 g, the temperature is 25℃, pH=7, and the adsorption time is 12 h, IO3 - When the concentration of Zr-CFs-5 is 100.0 mg / L, the effect of Zr-CFs-5 on IO3 - The adsorption capacity is 51.13 mg / g.

[0043] Example 9 The preparation method of the adsorption material of iodate radical comprises the following steps: 2.0 g of collagen fibers were soaked in 20 mL of 3% NaCl solution (pH adjusted to 1.7-2.0) for 12 h to obtain a collagen fiber soaking solution for use; 6.27 g of zirconium nitrate was dissolved in 40 mL of deionized water and added to the collagen fiber soaking solution and stirred for 6 h. The pH was adjusted to 4.0-4.5 within 2 h and then heated to 40 °C. After reacting for 4 h and overnight, the loaded Zr was filtered, washed, and dried the next day. 4+ of collagen fibers (Zr-CFs-9).

[0044] The Zr of the obtained Zr-CFs-9 4+ The loading amount is 0.214 g / g. When Zr-CFs-5 is 0.05 g, the temperature is 25℃, pH=7, and the adsorption time is 12 h, IO3 - When the concentration of Zr-CFs-5 is 100.0 mg / L, the effect of Zr-CFs-5 on IO3 - The adsorption capacity is 35.93 mg / g.

[0045] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. Iodate adsorption material, characterized in that Load Zr 4+ of collagen fibers.

2. The iodate adsorption material according to claim 1, wherein Zr per gram of iodate adsorption material 4+ The loading amount is 0.121~0.222 g.

3. A method for preparing an iodate adsorption material, characterized in that: include: After the collagen fibers were soaked in NaCl solution for 6-12 hours, Zr was added. 4+ The solutions are mixed evenly to react, and then filtered, washed and dried.

4. The preparation method according to claim 3, wherein When the collagen fibers were immersed in NaCl solution, the pH of the system was adjusted to 1.7~2.

0.

5. The preparation method according to claim 3, wherein The mass fraction of NaCl in the NaCl solution is 1.0-4.0%.

6. The preparation method according to claim 3, wherein Zr 4+ The sources include any one of zirconium sulfate, zirconium chloride, zirconium nitrate, zirconium oxychloride, and zirconium citrate.

7. The preparation method according to claim 3, wherein After drying, the content of Zr in each gram of iodate adsorption material 4 + The loading amount is 0.121~0.222 g.

8. The preparation method according to claim 3, wherein Join Zr 4+ The specific method for mixing the solution uniformly to react is: adding Zr 4+ After the solution is prepared, stir at 25°C for 4-6 hours, adjust the pH to 3.5-4.5, and react at 40-55°C for 4-6 hours and then overnight.

9. Use of the iodate adsorption material according to any one of claims 1 to 3 or the iodate adsorption material obtained by the preparation method according to any one of claims 3 to 8 in removing iodate from radioactive wastewater.

10. The use according to claim 9, characterized in that A continuous column adsorption apparatus was used.

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