Chromatographic separation method for efficiently extracting Sr < 2 + > from Sr < 2 + >-containing solution

Abstract

The invention discloses a separation method for extracting Sr < 2 + >, which comprises the following steps: firstly, fully soaking and swelling a self-made polystyrene matrix chromatographic filler in a nitric acid aqueous solution, filling the filler into a chromatographic column by a wet method, inputting an acidic mixed feed liquid containing Sr < 2 + > into the upper end of the chromatographic column, washing with water, and drying to obtain the Sr < 2 + >. And inputting the prepared mobile phase into a chromatographic column for elution, and collecting an eluent at the outlet end of the column, so that efficient separation of Sr < 2 + > is realized, and the eluted chromatographic column can be recycled. The method disclosed by the invention has the advantages of short separation time, high recovery rate and product purity and recyclability.

Description

Technical Field

[0001] The invention discloses a method for extracting Sr 2+ A separation technology, specifically involving a method of separating Sr 2+ Efficient extraction of Sr from solution 2+ chromatographic separation method. Background Art

[0002] 90 Sr is an ideal material for making nuclear battery energy. The nuclear battery made of it has the characteristics of small size, light weight, long life, and the energy size is not affected by external environmental temperature, pressure, electromagnetic factors, etc. It has been successfully applied in aerospace, polar regions, pacemakers and other fields, and has important uses in the military field. On the other hand, as a medical radioactive isotope, 90 The Sr market is vast and the demand is high. At present, the most commonly used method for separating rare earths in industry is extraction, which uses amide pod ether extractants such as DGA and TODGA for multiple extraction-strip separations. For example, the patent application with patent number [CN202311197857.2] provides "a method for extracting Sr(Ⅱ) from a solution containing Sr(II)", which belongs to the field of extraction and separation technology. However, multiple extraction-strip extractions are required to achieve high-purity Sr extraction, which is inefficient and complicated, and the results are not very ideal. In order to improve the process and increase Sr 2+ Extraction efficiency, explore a simple and efficient method to quickly extract Sr from mixed liquid 2+ The separation method seems to be extremely necessary. Summary of the invention

[0003] The present invention provides a method of preparing a Sr-containing 2+ Efficient extraction of Sr from solution 2+ The present invention also provides a column filler and a preparation method thereof which can be used in chromatographic separation technology.

[0004] A kind of 2+ Efficient extraction of Sr from solution 2+ The chromatographic separation method is as follows: first, the sulfonic acid group-modified microsphere filler is wet loaded into the chromatographic column after being fully soaked and swollen, and the Sr-containing 2+ The acidic mixed liquid is input into the upper end of the chromatographic column, and then washed with water, and then the prepared mobile phase is input into the chromatographic column for elution, and the eluent is collected at the outlet of the column, thereby achieving Sr 2+ Efficient separation.

[0005] in: The preparation method of the sulfonic acid group-modified microsphere filler is as follows: polyvinyl alcohol is added as a dispersant to the aqueous phase, mechanically stirred and dissolved at 80-90°C, and after cooling to room temperature, 0.1-0.5 g of sodium dodecyl sulfate is added to mix evenly. 10-15 ml of styrene is added to the organic phase as a monomer, and then an equal amount of divinylbenzene is added as a crosslinking agent, and then 0.05 g of initiator benzoyl peroxide is added thereto and mixed evenly, and then the organic phase is added to the aqueous phase, heated and stirred to fully react, and polystyrene-based microspheres are obtained. The obtained polystyrene-based microspheres are washed and dried with hot water and anhydrous ethanol in turn, and then concentrated sulfuric acid is added and heated and stirred. After reacting for twenty hours, the sulfonic acid group-modified microsphere filler is obtained; Contains Sr 2+ The acidic mixed liquid contains Sr 2+ The acidic mixed liquid refers to any acidic liquid, the components of which, except for Sr 2+ In addition, there is no limit on the presence of any other metal ion components, including Sr 2 Alkaline earth metal ions that are more difficult to separate from each other; The mobile phase was a chelating acid solution.

[0006] Preferably, in the separation method of the present invention, the molar ratio of the alkaline earth elements to be separated is 1:1:1, the flow rate of the input mobile phase is 5-10 ml / min, and the mobile phase is a 0.15 mol / L sodium citrate aqueous solution.

[0007] The present invention provides a column packing preparation method that can be used for chromatographic separation technology. Polyvinyl alcohol is added as a dispersant in the aqueous phase, mechanically stirred and dissolved at 80-90°C, and after cooling to room temperature, 0.1-0.5 g of sodium dodecyl sulfate is added to mix evenly, 10-15 ml of styrene is added to the organic phase as a monomer, an equal amount of divinylbenzene is used as a cross-linking agent, and 0.05 g of initiator benzoyl peroxide is added thereto to mix evenly, and then the organic phase is added to the aqueous phase, heated and stirred to fully react to obtain polystyrene-based microspheres, and the obtained polystyrene-based microspheres are washed and dried with hot water and anhydrous ethanol in turn, and then concentrated sulfuric acid is added to heat and stir, and the sulfonic acid microsphere filler is obtained after reacting for twenty hours. The organic phase here refers to the configured organic mixed system.

[0008] The method of the present invention overcomes the traditional Sr 2+ The extraction process has the disadvantages of long cycle, large equipment investment and complex process. A rapid separation method is provided to achieve rapid separation of alkaline earth metal elements under acidic conditions through chromatography technology, and this method can be industrialized. Compared with the prior art, the beneficial effects of the present invention are: 1) Compared with the prior art, the present invention realizes the Sr-containing 2+Rapid separation of the solution, separation time <10 hours, recovery rate reaches 98%, purity reaches 99%.

[0009] 2) The chromatographic separation method used in the present invention is not affected by Sr-containing 2+ The method can be used to reduce the influence of acidity in the raw material solution and is suitable for gram-scale Sr extraction and can be used for industrial scale-up.

[0010] In summary, the present invention can achieve Sr-containing 2+ The rapid separation of the solution has a significant impact on improving the scientific and technological content and promoting the technological progress of the industry. The present invention has good practical application value and can be used for high-level radioactive waste liquid 90 It provides a research basis for the separation and extraction of Sr. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a separation flow chart of the present invention.

[0012] Figure 2 This is the slurry-liquid separation result of Ca:Sr:Ba=1:1:1.

[0013] Figure 3 This is the slurry-liquid separation result of Ca:Sr:Ba=1:4:1.

[0014] Figure 4 This is the slurry-liquid separation result of Sr:La:Eu:U =1:1:1:1. DETAILED DESCRIPTION

[0015] The present invention is described in detail below with reference to the embodiments and the accompanying drawings.

[0016] 1) Preparation of polystyrene-based chromatographic packing The preparation method of polystyrene matrix chromatographic filler is as follows: polyvinyl alcohol is added as a dispersant to the aqueous phase, mechanically stirred and dissolved at 85°C, and after cooling to room temperature, 0.1g of sodium dodecyl sulfate is added to mix evenly. 10-15ml of styrene is added to the organic phase as a monomer, an equal amount of divinylbenzene is used as a crosslinking agent, and 0.05g of initiator benzoyl peroxide is added thereto and mixed evenly, and then the organic phase is added to the aqueous phase, heated and stirred to fully react, and polystyrene matrix microspheres are obtained. The obtained polystyrene matrix microspheres are washed and dried with hot water and anhydrous ethanol in turn, and then concentrated sulfuric acid is added to heat and stir, and after reacting for twenty hours, sulfonic acid group-modified microsphere filler is obtained.

[0017] 2) Preparation of experimental raw material solution and mobile phase a Test raw material solution ① Dissolve Ca(NO3)2, Sr(NO3)2 and Ba(NO3)2 in dilute nitric acid to obtain a raw material solution with a molar ratio of Ca:Sr:Ba=1:4:1, in which the total amount of alkaline earth elements is 1-10g and the nitric acid concentration is 0.1 mol / L.

[0018] ② Dissolve Sr(NO3)2, La(NO3)3·6H2O, Eu(NO3)3·6H2O and UO2(NO3)2·6H2O in dilute nitric acid to obtain a raw material solution with a molar ratio of Sr:La:Eu:U=1:1:1:1, in which the total amount of Sr element is 1-10g and the concentration of nitric acid is 0.1 mol / L. b Prepare the mobile phase Weigh 77.45g of sodium citrate, dissolve it in ultrapure water, make up to volume in a 2L volumetric flask, adjust the pH to 5.2-5.8, and obtain a mobile phase with a concentration of 0.15 mol / L.

[0019] 3) Separation of acidic alkaline earth metal element liquid a. Soak 30-50g of self-made sulfonic acid filler in 0.1mol / L nitric acid for 12h, and then wet-pack it into the chromatographic column after it is fully swollen.

[0020] b. Inject the prepared raw material solution with a molar ratio of Ca:Sr:Ba=1:4:1 at a flow rate of 5.0 ml / min, and accumulate 6L of liquid to be adsorbed on the upper end of the chromatographic column. After the loading is completed, wash with water 2-3 times the volume of the bed.

[0021] c The mobile phase A was introduced into the chromatographic column at a flow rate of 10-15 ml / min through an infusion pump, and the effluent was collected at the outlet section. After dilution, the alkaline earth metal elements were tested using an ICP-OES to obtain Figure 3 As a result, the three alkaline earth metal elements were separated quickly at one time and recovered with 90% purity within 8 hours, with a yield of up to 95%.

[0022] For the separation and extraction of Sr in a more complex system, the molar ratio of the feed liquid is Sr:La:Eu:U=1:1:1:1. The separation results are as follows: Figure 4 As shown, the separation time was less than 9 hours, the recovery rate reached 98%, and the purity reached 99%.

[0023] From the above examples, it can be seen that the present invention can effectively realize the 2+ Efficient extraction of Sr from solution 2+ .

[0024] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them. Although the present invention is described in detail with reference to the above embodiments, ordinary technicians in the field should understand that they can still modify the technical solutions recorded in the above embodiments, or replace some of the technical features therein with equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention. The parts not described in detail in the present invention are well-known technologies for those skilled in the art.

Claims

1. A kind of Sr-containing 2+ Efficient extraction of Sr from solution 2+ A chromatographic separation method, characterized in that The chromatographic column was wet loaded with the fully soaked and swollen sulfonic acid microsphere filler. 2+ The acidic mixed liquid is input into the upper end of the chromatographic column, and then washed with water, and then the prepared mobile phase is input into the chromatographic column for elution, and the eluent is collected at the outlet of the column, thereby achieving Sr 2+ Efficient separation of The preparation method of the sulfonic acid group-modified microsphere filler is as follows: polyvinyl alcohol is added as a dispersant to the aqueous phase, mechanically stirred and dissolved at 80-90° C., after cooling to room temperature, 0.1-0.5 g of sodium dodecyl sulfate is added to mix evenly, 10-15 ml of styrene is added to the organic phase as a monomer, an equal amount of divinylbenzene is used as a crosslinking agent, and 0.05 g of initiator benzoyl peroxide is added thereto to mix evenly, then the organic phase is added to the aqueous phase, heated and stirred to fully react to obtain polystyrene-based microspheres, the obtained polystyrene-based microspheres are washed and dried with hot water and anhydrous ethanol in turn, and then concentrated sulfuric acid is added to heat and stir, and the sulfonic acid microspheres are obtained after reacting for 20 hours; Contains Sr 2+ The acidic mixed liquid refers to any acidic liquid, the components of which except Sr 2+ In addition, the presence of any other metal ion components is not limited; The mobile phase was a chelating acid solution.

2. Sr according to claim 1 2+ The extraction method is characterized in that The mobile phase is a 0.1-0.2 mol / L sodium citrate aqueous solution.

3. Sr according to claim 1 or 2 2+ The extraction method is characterized in that The molar ratio of adjacent alkaline earth elements to be separated is 1:1:1, the flow rate of the input mobile phase is 5-10 ml / min, and the mobile phase is a 0.15 mol / L sodium citrate aqueous solution.

4. A method for preparing a column filler that can be used for chromatographic separation technology, characterized in that: Add polyvinyl alcohol as a dispersant to the aqueous phase, stir mechanically at a certain temperature to dissolve, and after cooling to room temperature, add 0.1-0.5 g of sodium dodecyl sulfate to mix evenly, add 10-15 ml of styrene as a monomer and an equal amount of divinylbenzene as a cross-linking agent to the organic phase, and then add 0.05 g of initiator benzoyl peroxide to mix evenly, then add the organic phase to the aqueous phase, heat and stir to react fully to obtain polystyrene-based microspheres, wash the obtained polystyrene-based microspheres with hot water and anhydrous ethanol in turn, dry them, add concentrated sulfuric acid and heat and stir, and react for twenty hours to obtain sulfonic acid microspheres.

5. A column packing prepared by the method of claim 4 and can be used for chromatographic separation technology.

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