Preparation method of acid-resistant high-selectivity antimony silicate

Abstract

The application discloses a preparation method of acid-resistant high-selectivity antimony silicate, and belongs to the technical field of material preparation and the technical field of water treatment. The preparation method of the acid-resistant high-selectivity antimony silicate comprises the following steps: mixing a suspension after Sb2O5 is reacted with concentrated HCl and a water-soluble silicate solution, hydrolyzing and standing, centrifuging, washing, and drying to obtain the acid-resistant high-selectivity antimony silicate. The acid-resistant high-selectivity antimony silicate inorganic material prepared by the method has the advantages of radiation resistance and acid resistance, can be used for adsorbing liquid radioactive effluent cobalt-60 and other corrosion product ions of a pressurized water reactor nuclear power plant, has a good separation effect, and the removal rate of 10 mg·L ‑1 of Co 2+ can reach more than 95%.

Description

Technical Field

[0001] This application relates to a method for preparing acid-resistant, highly selective antimony silica, belonging to the fields of materials preparation technology and water treatment technology. Background Technology

[0002] Nuclear energy is a high-energy-density clean energy source that can replace traditional fossil fuels, effectively reducing carbon emissions during energy production. However, the nuclear energy production process generates large amounts of wastewater, waste gas, and solid waste containing radioactive nuclides and other polluting metallic substances. Nuclear wastewater is characterized by high concentration, high radioactivity, and high toxicity. The radioactive nuclides mainly include tritium, etc. 90 Sr、 137 Cs、 60 Polluting metallic substances, such as Co, mainly include uranium, plutonium, cadmium, and mercury. These radioactive nuclides and heavy metals are highly harmful to the environment and organisms.

[0003] Nuclear wastewater treatment methods include physical, chemical, biological, and advanced treatment methods. Physical treatment methods mainly include sedimentation, filtration, and flotation. Physical treatment can remove suspended solids and colloidal particles from wastewater; however, it cannot remove radionuclides and heavy metal pollutants. Chemical treatment methods mainly include neutralization, oxidation-reduction, and complexation precipitation. Chemical treatment can remove acidic or alkaline substances and some heavy metal pollutants from wastewater; however, it is relatively difficult to remove radionuclides. Biological treatment methods mainly include aerobic and anaerobic biological treatment. Biological treatment can degrade organic matter in wastewater and remove some heavy metal pollutants, but it is relatively difficult to remove radionuclides. Advanced treatment methods mainly include adsorption, ion exchange, membrane separation, and evaporation concentration. Advanced treatment can further remove heavy metal pollutants and radionuclides from wastewater. However, advanced treatment methods are costly and may pose secondary pollution problems.

[0004] The International Atomic Energy Agency (IAEA)'s overall strategy for treating nuclear waste liquids is volume reduction and emission reduction, which means minimizing the generation of nuclear waste liquids and reducing the concentration of effluents released into the environment. Technologies such as adsorption or ion exchange have been used to remove these substances, and have generally been successful. However, the removal of certain radionuclides is more difficult. Especially in acidic media, these nuclides are difficult to remove using known adsorption or ion exchange techniques. Furthermore, the presence of other alkali metal or alkaline earth metal ions in the solution can interfere with the adsorption of cesium, strontium, and cobalt. Currently, commercially available materials for removing cesium, strontium, and cobalt include zeolites, sodium titanate, titanium silicates, and titanium oxide-based titanium-containing materials, which are more efficient in neutral or alkaline media.

[0005] Therefore, there is an urgent need to explore and research new materials to improve the efficiency of radioactive ion treatment under acidic conditions and reduce treatment costs, so as to provide an effective solution to the problem of radioactive material pollution in the environment. Summary of the Invention

[0006] According to one aspect of this application, a method for preparing acid-resistant, highly selective antimony silicate is provided. The acid-resistant, highly selective antimony silicate inorganic material prepared by this method has radiation resistance and acid resistance, and can be used for the adsorption of cobalt-60 and other corrosion product ions from liquid radioactive effluents in pressurized water reactor nuclear power plants, exhibiting excellent separation performance for 10 mg·L⁻¹ ions. -1 Co 2+ The removal rate can reach over 95%.

[0007] The method for preparing acid-resistant, highly selective antimony silicate according to this application includes: mixing a suspension of Sb2O5 reacted with concentrated HCl and a water-soluble silicate solution, hydrolyzing and allowing to stand, centrifuging, washing, and drying to obtain the acid-resistant, highly selective antimony silicate.

[0008] Optionally, the concentration of concentrated HCl is 6-12M.

[0009] Optionally, Sb2O5 and concentrated HCl are mixed and reacted to obtain a suspension of Sb2O5 and concentrated HCl.

[0010] Optionally, the reaction temperature is 60-100℃; preferably, the reaction temperature is 70-80℃.

[0011] Optionally, the reaction time is 1-10 hours.

[0012] Preferably, the reaction time is 6-8 hours.

[0013] Optionally, the solid-liquid ratio of Sb2O5 to concentrated HCl is (6-8) g: (60-100) mL.

[0014] Optionally, the volume ratio of water to concentrated HCl is (50-55):(60-100).

[0015] Optionally, the water-soluble silicate in the water-soluble silicate solution is selected from one or more of sodium silicate, potassium silicate, lithium silicate, cesium silicate, and sodium metasilicate.

[0016] Optionally, the molar ratio of Si to Sb in the water-soluble silicate solution is (0.1-10):1; preferably, the molar ratio of Si to Sb in the water-soluble silicate solution is (0.4-0.6):1.

[0017] Optionally, the molar ratio of Si in the water-soluble silicate solution to Sb in Sb₂O₅ is independently selected from any one of 0.4:1, 0.5:1, 0.6:1, 1:1, 2:1, 5:1, 8:1, 10:1 or a range between any two of the above.

[0018] Optionally, silicate and water are mixed and stirred to obtain a water-soluble silicate solution.

[0019] Optionally, the stirring temperature is 30-80℃.

[0020] Optionally, the hydrolysis temperature is 30-95℃; preferably, the hydrolysis temperature is 60-80℃.

[0021] Optionally, the hydrolysis time is 3-12 hours.

[0022] Optionally, the drying temperature is 60-80℃, and the drying time is 1-5 days.

[0023] The beneficial effects that this application can produce include:

[0024] 1) The preparation method provided in this application yields an acid-resistant, highly selective antimony silicate inorganic material that is radiation-resistant and acid-resistant. It can be used for the adsorption of cobalt-60 and other corrosion product ions from liquid radioactive effluents in pressurized water reactor nuclear power plants, and exhibits excellent separation performance.

[0025] 2) The preparation method provided in this application yields an acid-resistant, highly selective antimony silicate inorganic material that, after adsorbing radioactive elements, can be directly landfilled without complex treatment.

[0026] 3) The preparation method provided in this application yields an acid-resistant, highly selective antimony silicate inorganic material, which is effective against Cs in the pH range of 1-10. + Co 2+ 、Sr 2+ The method of this application has a good removal effect on metal ions, while the materials obtained by the preparation methods in the prior art are mostly suitable for neutral to alkaline pH ranges. The preparation method of this application has obvious advantages over the prior art.

[0027] 4) The preparation method provided in this application yields an acid-resistant, highly selective antimony silicate inorganic material, which, for 10 mg·L⁻¹, exhibits high selectivity. -1 Co 2+ The removal rate can reach over 95%.

[0028] 5) The preparation method provided in this application is simple to operate, uses inexpensive and readily available raw materials, and does not require complex and expensive instruments and complicated operating steps. It can obtain acid-resistant and highly selective antimony silicate materials, which can be used in pressurized water reactor nuclear power plant effluent treatment systems and can also be applied in general wastewater treatment containing metal cations. Attached Figure Description

[0029] Figure 1 The XRD pattern of the acid-resistant, highly selective antimony silicate material obtained in Example 1 is shown below.

[0030] Figure 2 Co in Example 1 2+ The effect curve of initial concentration on removal rate. Detailed Implementation

[0031] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0032] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased through commercial channels.

[0033] X-ray powder diffraction (XRD): The synthesized sample was subjected to phase analysis using a Rigaku MiniFlex II desktop powder diffractometer (Japan), with Cu Kα, λ = 0.15406 nm, tube voltage 30 kV, tube current 15 mA, scanning range 2θ 5°–85°, and step size 0.02°·min. -1 .

[0034] The adsorption experiment was conducted using inductively coupled plasma optical emission spectrometry (ICP-OES). The test samples were filtered using a 0.22 μm syringe-type membrane filter, and the filtered samples were then sent for ICP-OES testing.

[0035] Example 1

[0036] This embodiment provides a method for preparing acid-resistant, highly selective antimony silica, which specifically includes the following steps:

[0037] 7.12 g of Sb₂O₅ was weighed and reacted with 53 mL of ultrapure water and 60 mL of 12 M concentrated HCl in an 80 °C hot water bath for 6 h to obtain solution A. 4.90 g of sodium silicate was weighed and added to 100 mL of ultrapure water, and reacted with stirring at 65 °C for 1 h to obtain solution B. A and B were mixed, and 250 mL of ultrapure water was added. The mixture was hydrolyzed in a 65 °C water bath for 8 h, then allowed to stand overnight. The gel-like product was then centrifuged at high speed and repeatedly centrifuged and washed 6 times with ultrapure water. The resulting precipitate was vacuum dried at 70 °C for 2 days and then ground to obtain an acid-resistant, highly selective antimony silicate material. XRD analysis of the obtained antimony silicate material was performed, and the results are as follows: Figure 1As shown, the results indicate that it is a crystalline material. Titanium antimonate was used for Co... 2+ The adsorption of its Co 2+ The relationship between initial concentration and removal rate is as follows: Figure 2 As shown, in Co 2 + The initial concentration was 10 mg·L. -1 At that time, its removal rate can reach 96%.

[0038] Example 2

[0039] This embodiment provides a method for preparing acid-resistant, highly selective antimony silica, which specifically includes the following steps:

[0040] 6.41 g of Sb₂O₅ was weighed and reacted with 50 mL of ultrapure water and 100 mL of 8M concentrated HCl in a 70°C hot water bath for 8 h to obtain solution A. 6.72 g of potassium silicate was weighed and added to 150 mL of ultrapure water, and reacted with stirring at 70°C for 1 h to obtain solution B. A and B were mixed, and 300 mL of ultrapure water was added. The mixture was hydrolyzed in a 70°C water bath for 7 h, then allowed to stand overnight. The gel-like product was then centrifuged at high speed, repeatedly centrifuged and washed 6 times with ultrapure water. The resulting precipitate was vacuum dried at 70°C for 2 days and ground to obtain an acid-resistant, highly selective antimony silicate material. The antimony silicate material was subjected to Sr under acidic conditions. 2+ Adsorption experiments showed that at pH 3.0, the adsorption of Sr... 2+ The removal rate can still reach over 90%, demonstrating good acid resistance and application potential.

[0041] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A method for preparing acid-resistant high-selectivity antimony silicate, characterized in that, The application relates to an acid-resistant high-selectivity silicon antimonate, a preparation method thereof and application thereof. Sb2O5 is mixed with concentrated HCl with a concentration of 6-12 M at a solid-liquid ratio of (6-8) g:(60-100) mL, and the mixture is reacted at 60-100 DEG C for 1-10 h to obtain a suspension of Sb2O5 after reacting with concentrated HCl; The suspension is mixed with a water-soluble silicate solution, hydrolysis is carried out, and then centrifugation, washing and drying are carried out to obtain the acid-resistant high-selectivity silicon antimonate. The water-soluble silicate in the water-soluble silicate solution is selected from any one or more of sodium silicate, potassium silicate, lithium silicate, cesium silicate and sodium metasilicate; The molar ratio of Si in the water-soluble silicate solution to Sb in Sb2O5 is (0.1-10):1; The hydrolysis temperature is 30-95 DEG C, and the hydrolysis time is 3-12 h; The drying temperature is 60-80 DEG C, and the drying time is 1-5 d.

2. The method for preparing acid-resistant, highly selective antimony silica according to claim 1, characterized in that, The concentration of the concentrated HCl is 10-12 M.

3. The method for preparing acid-resistant, highly selective antimony silica according to claim 1, characterized in that, The reaction temperature is 70-80 DEG C.

4. The method for preparing acid-resistant, highly selective antimony silicate according to claim 3, characterized in that, The reaction time is 6-8 h.

5. The method for preparing acid-resistant, highly selective antimony silica according to claim 3, characterized in that, In the suspension of Sb2O5 and concentrated HCl, the volume ratio of water to concentrated HCl is (50-55):(60-100).

6. The method of claim 1, wherein the acid-resistant high-selectivity antimony silicate is prepared by the steps of: The molar ratio of Si in the water-soluble silicate solution to Sb in Sb2O5 is (0.4-0.6):

1.

7. The method of claim 1, wherein the acid-resistant high-selectivity antimony silicate is prepared by the steps of: The hydrolysis temperature is 60-80 DEG C. ​ 8. The method of claim 1, wherein the acid-resistant high-selectivity antimony silicate is prepared by the steps of: preparing a mixture of a silane compound, an antimony compound, and a solvent; and adding a base to the mixture. The hydrolysis time is 6-10 h.

9. The method of claim 1, wherein the acid-resistant high-selectivity antimony silicate is prepared by the steps of: preparing a mixture of a silane compound, an antimony compound, and a solvent; and adding a base to the mixture. The drying temperature is 70 DEG C, and the drying time is 2-3 d.

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