A separation and purification method for preparing lead-212 and actinium-225 by photo-nuclear reaction

Abstract

The present application relates to radionuclide separation and purification technical field, specifically disclose a kind of separation and purification method for preparing lead-212 and actinium-225 by photo nuclear reaction method.It includes the following steps: radium target solution is sequentially passed through lead resin column and DGA resin column, and recovery liquid is obtained;First eluent is used to elute lead resin column, and lead-212 first purification liquid is obtained;Second eluent is used to elute DGA resin column, and actinium-225 first purification liquid is obtained;Lead-212 first purification liquid is introduced into first LN resin column, and third eluent is used to elute first LN resin column, then third desorption liquid is introduced into first LN resin column, and lead-212 second purification liquid is obtained;Actinium-225 first purification liquid is introduced into second LN resin column, and fourth eluent is used to elute second LN resin column, then fourth desorption liquid is introduced into second LN resin column, and actinium-225 second purification product solution is obtained.The present application effectively avoids the cumbersome operation steps such as medium conversion, improves the separation and purification efficiency of lead-212 and actinium-225 in radium target.

Description

Technical Field

[0001] This invention relates to the field of radionuclide separation and purification technology, and in particular to a separation and purification method for preparing lead-212 and actinium-225 by photonuclear reaction. Background Technology

[0002] Targeted alpha therapy utilizes alpha radionuclides combined with macromolecules to form radionuclide conjugates. These conjugates specifically target cancer cells, focusing the radiation emitted by the radioactive isotopes onto the tumor tissue. Alpha radionuclides emit alpha particles with higher energy and shorter penetration, resulting in less damage to healthy tissue and making them a significant area of ​​interest in cancer treatment. Among alpha radionuclides, actinium-225 has attracted considerable attention due to its suitable half-life and unique decay properties. However, large-scale production and purification technologies for actinium-225 are still in the experimental research stage, with limited global production, resulting in a significant supply gap for targeted alpha therapy.

[0003] Actinium-225 can be prepared by accelerator irradiation of radium-226 via photonuclear reaction. Accelerated electrons bombard a tantalum or tungsten conversion target, and radium-226 is irradiated with high-energy gamma rays generated by bremsstrahlung. Radium-226 reacts to form radium-225, which then undergoes beta decay to form actinium-225. Conversely, radium-224, generated by irradiating radium-226, decays to form lead-212. In other words, high-energy gamma ray irradiation of a radium-226 target can generate both radium-225 and radium-224. Radium-225 undergoes beta decay to form actinium-225, and radium-224 undergoes four alpha decays to form lead-212. To extract lead-212 and actinium-225 separately from the irradiated target, the individual nuclides of lead-212 or actinium-225 need to be separated and purified. If existing technologies are used directly, media conversion is required, which generally involves operations such as evaporation and dissolution. The process is relatively cumbersome and not easy to automate. In addition, existing technologies are generally designed for the separation of radium at the hundred-milligram level and cannot be directly applied to the separation and purification of lead-212 and actinium-225 in radium targets at the gram level and above, thus affecting the separation and purification efficiency of lead-212 and actinium-225 in radium targets. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the present invention aims to provide a separation and purification method and a preparation method for lead-212 and actinium-225 prepared by photonuclear reaction, so as to improve the recovery rate and decontamination coefficient of lead-212 and actinium-225.

[0005] The technical solution adopted in this invention is as follows:

[0006] A method for separating and purifying lead-212 and actinium-225 prepared by photonuclear reaction includes the following steps:

[0007] S1. Pass the radium target dissolution solution sequentially through a lead resin column and a DGA resin column to obtain the recovery solution;

[0008] S2. The lead resin column is eluted with the first elution solution to obtain a primary purified lead-212 solution.

[0009] S3. Elute the DGA resin column with the second eluent to obtain Actinium-225 primary purification solution;

[0010] S4. The lead-212 primary purification solution is introduced into the first LN resin column, and the first LN resin column is eluted with the third elution solution to obtain the first waste liquid. Then, the third desorption solution is introduced into the first LN resin column to obtain the lead-212 secondary purification solution.

[0011] S5. The Actinium-225 primary purification solution is introduced into the second LN resin column, and the second LN resin column is eluted with the fourth elution solution to obtain the second waste liquid. Then, the fourth desorption solution is introduced into the second LN resin column to obtain the Actinium-225 secondary purification product solution.

[0012] Optionally, in step S2, after rinsing the lead resin column with the first rinsing solution, the first desorption solution is then introduced into the lead resin column.

[0013] Optionally, in step S3, the DGA resin column is rinsed with a second rinsing solution, and then a second desorption solution is introduced into the DGA resin column.

[0014] Optionally, before step S1, 20-40 mL of 0.5-3.0 mol / L HNO3 solution is passed sequentially through a lead resin column and a DGA resin column to obtain a first washing solution.

[0015] Optionally, the volume of lead resin in the lead resin column is 1 mL; the first eluent is 50-70 mL of 0.1-1.0 mol / L HNO3 solution, and the volume of DGA in the DGA resin column is 5 mL; the second eluent is 50-120 mL of 0.5-3.0 mol / L HNO3 solution.

[0016] Optionally, the first desorption solution is 20–40 mL of 0.0001–0.001 mol / L HNO3 solution;

[0017] The second desorption solution is 20-40 mL of 0.001-0.01 mol / L HNO3 solution.

[0018] Optionally, the volume of LN resin in the first LN resin column is 5 mL. Before step S4, 20–40 mL of 0.005–0.01 mol / L HNO3 solution is passed through the first LN resin column to obtain a second washing solution; the third elution solution is 20–40 mL of 0.005–0.01 mol / L HNO3 solution, and the third desorption solution is 10–40 mL of 0.5–1.0 mol / L HNO3 solution.

[0019] Optionally, the volume of LN resin in the second LN resin column is 5 mL. Before step S5, 20–40 mL of 0.01–0.05 mol / L HNO3 solution is passed through the second LN resin column to obtain a third washing solution; the fourth elution solution is 50–70 mL of 0.01–0.05 mol / L HNO3 solution, and the fourth desorption solution is 10–40 mL of 0.5–1.0 mol / L HNO3 solution.

[0020] Optionally, the volume of the lead-212 primary purification solution is 20-40 mL; in step S5, the volume of the actinium-225 primary purification solution is 20-40 mL.

[0021] The beneficial effects of this invention are as follows: The method for separating and purifying lead-212 and actinium-225 from an irradiated radium target disclosed in this application not only has the advantages of simple operation and easy automation, but also performs excellently in improving efficiency and purity. Utilizing the adsorption and desorption characteristics of different resins for radium-226, lead-212, and actinium-225, this invention provides a method for directly separating and purifying lead-212 and actinium-225 from the radium target solution without media conversion. This breakthrough method not only simplifies the operation steps but also significantly improves the efficiency and reliability of separation and purification. Furthermore, the process flow of directly performing secondary purification from the primary purification desorption solution further ensures the high purity of the final product.

[0022] This invention achieves precise matching of adsorption and desorption conditions between each separation and purification step, effectively avoiding cumbersome operation steps such as medium conversion, thereby greatly reducing operation time and cost, and improving the separation and purification efficiency of lead-212 and actinium-225 in radium targets. Detailed Implementation

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0024] Example

[0025] Example 1

[0026] A 1 mL lead resin column and a 5 mL DGA resin column were packed together using a wet method and connected in series, with the lead resin column on top and the DGA resin column on the bottom. 20 mL of 0.5 mol / L HNO3 solution was passed sequentially through the lead resin column and the DGA resin column at a flow rate of 0.5–0.8 mL / min using a pipette, syringe pump, or peristaltic pump to obtain the first washing solution. Next, 20 mL of irradiated radium target simulant solution was passed sequentially through the lead resin column and the DGA resin column at a flow rate of 0.5 mL / min using a pipette, syringe pump, or peristaltic pump. The effluent could be used for further separation and purification of lead-212 simulants Pb and actinium-225 simulants La, or as a recovery solution for recovering radium-226 simulants Ba. Then, the lead resin column and the DGA resin column were separated for the first separation and purification of lead-212 simulants Pb and actinium-225 simulants La, respectively.

[0027] Use a pipette, syringe pump, or peristaltic pump to pass 50 mL of 0.5 mol / L HNO3 solution through a lead resin column at a flow rate of 0.5 mL / min to obtain the first effluent; then use a pipette, syringe pump, or peristaltic pump to pass 40 mL of 0.001 mol / L HNO3 solution through a lead resin column at a flow rate of 0.5 mL / min to obtain the first purified solution of the lead-212 simulant Pb.

[0028] Use a pipette, syringe pump, or peristaltic pump to pass 100 mL of 0.5 mol / L HNO3 solution through a DGA resin column at a flow rate of 0.5 mL / min to obtain the second effluent; then use a pipette, syringe pump, or peristaltic pump to pass 40 mL of 0.01 mol / L HNO3 solution through a DGA resin column at a flow rate of 0.5 mL / min to obtain the first purified solution of the actinium-225 simulant La.

[0029] A 5 mL LN resin column was wet-packed. 20 mL of 0.01 mol / L HNO3 solution was passed through the LN resin column manually, by syringe pump, or peristaltic pump at a flow rate of 0.5–0.8 mL / min to obtain the first washing solution. Then, 40 mL of the lead-212 simulant Pb primary purification product solution was passed through the LN resin column at a flow rate of 0.5 mL / min using a pipette, syringe pump, or peristaltic pump. Next, 50 mL of 0.01 mol / L HNO3 solution was passed through the LN resin column at a flow rate of 0.5 mL / min using a pipette, syringe pump, or peristaltic pump to obtain the first waste solution. Finally, 20 mL of 0.5 mol / L HNO3 solution was passed through the LN resin column at a flow rate of 0.5 mL / min using a pipette, syringe pump, or peristaltic pump to obtain the lead-212 simulant Pb secondary purification product solution.

[0030] A 5 mL second LN resin column was wet-packed. 20 mL of 0.05 mol / L HNO3 solution was passed through the second LN resin column manually, by syringe pump, or peristaltic pump at a flow rate of 0.5 mL / min to obtain the second washing solution. Then, 40 mL of the primary purified product solution of the actinium-225 simulant La was passed through the second LN resin column at a flow rate of 0.5 mL / min using a pipette, syringe pump, or peristaltic pump. Next, 50 mL of 0.05 mol / L HNO3 solution was passed through the second LN resin column at a flow rate of 0.5 mL / min using a pipette, syringe pump, or peristaltic pump to obtain the second waste solution. Finally, 20 mL of 0.5 mol / L HNO3 solution was passed through the second LN resin column at a flow rate of 0.5 mL / min using a pipette, syringe pump, or peristaltic pump to obtain the secondary purified product solution of actinium-225.

[0031] Example 2

[0032] A method for separating and purifying lead-212 and actinium-225 prepared by photonuclear reaction differs from Example 1 in that the first eluent is 30 mL of 0.1 mol / L HNO3 solution.

[0033] Example 3

[0034] A method for separating and purifying lead-212 and actinium-225 prepared by photonuclear reaction differs from Example 1 in that the first eluent is 50 mL of 0.1 mol / L HNO3 solution.

[0035] Example 4

[0036] A method for separating and purifying lead-212 and actinium-225 prepared by photonuclear reaction differs from Example 1 in that the first eluent is 30 mL of 0.5 mol / L HNO3 solution.

[0037] Example 5

[0038] A method for separating and purifying lead-212 and actinium-225 prepared by photonuclear reaction differs from Example 1 in that the first eluent is 50 mL of 0.5 mol / L HNO3 solution.

[0039] Example 6

[0040] A method for separating and purifying lead-212 and actinium-225 prepared by photonuclear reaction differs from Example 1 in that the volume of DGA resin is 2 mL and the second eluent is 10 mL of 0.5 mol / L HNO3 solution.

[0041] Example 7

[0042] A separation and purification method for preparing lead-212 and actinium-225 by photonuclear reaction differs from Example 1 in that the volume of DGA resin is 5 mL and the second eluent is 50 mL of 1.0 mol / L HNO3 solution.

[0043] Example 8

[0044] A separation and purification method for preparing lead-212 and actinium-225 by photonuclear reaction differs from Example 1 in that the volume of DGA resin is 5 mL and the second eluent is 120 mL of 1.0 mol / L HNO3 solution.

[0045] Example 9

[0046] A separation and purification method for preparing lead-212 and actinium-225 by photonuclear reaction differs from Example 1 in that the volume of DGA resin is 5 mL, and the second elution solution is 10 mL of 0.5 mol / L HNO3 and 40 mL of 3.0 mol / L HNO3 solution, which are used for elution sequentially.

[0047] Example 10

[0048] A separation and purification method for preparing lead-212 and actinium-225 by photonuclear reaction differs from Example 1 in that the volume of DGA resin is 5 mL, and the second elution solution is 10 mL of 0.5 mol / L HNO3 and 90 mL of 3.0 mol / L HNO3 solution, which are used for elution sequentially.

[0049] Example 11

[0050] A 1 mL lead resin column and a 5 mL DGA resin column were packed together using a wet method and connected in series. 20 mL of 0.5 mol / L HNO3 solution was passed sequentially through the lead resin column and the DGA resin column at a flow rate of 0.5 mL / min using a pipette, syringe pump, or peristaltic pump to obtain the first washing solution. Next, 20 mL of simulated irradiation target solution was passed sequentially through the lead resin column and the DGA resin column at a flow rate of 0.5 mL / min using a pipette, syringe pump, or peristaltic pump. The effluent could be used for further separation and purification of lead-212 simulant Pb and actinium-225 simulant La, or as a recovery solution for the recovery of radium-226. Then, the lead resin column and the DGA resin column were separated for the first separation and purification of lead-212 simulant Pb and actinium-225 simulant La, respectively.

[0051] Use a pipette, syringe pump, or peristaltic pump to pass 50 mL of 0.1 mol / L HNO3 solution through a lead resin column at a flow rate of 0.5 mL / min to obtain the first effluent; then use a pipette, syringe pump, or peristaltic pump to pass 20 mL of 0.0001 mol / L HNO3 solution through a lead resin column at a flow rate of 0.5 mL / min to obtain the first purified solution of lead-212 simulant Pb.

[0052] Use a pipette, syringe pump, or peristaltic pump to pass 50 mL of 0.5 mol / L HNO3 solution through a DGA resin column at a flow rate of 0.5 mL / min to obtain the second effluent; then use a pipette, syringe pump, or peristaltic pump to pass 20 mL of 0.001 mol / L HNO3 solution through a DGA resin column at a flow rate of 0.5 mL / min to obtain the first purified solution of actinium-225 analog La.

[0053] A 5 mL LN resin column was wet-packed. 20 mL of 0.005 mol / L HNO3 solution was passed through the LN resin column manually, by syringe pump, or peristaltic pump at a flow rate of 0.5 mL / min to obtain the first washing solution. Then, 20 mL of the first-stage purified lead-212 simulant Pb product solution was passed through the LN resin column at a flow rate of 0.5 mL / min using a pipette, syringe pump, or peristaltic pump. Next, 50 mL of 0.005 mol / L HNO3 solution was passed through the LN resin column at a flow rate of 0.5 mL / min using a pipette, syringe pump, or peristaltic pump to obtain the first waste solution. Finally, 10 mL of 0.5 mol / L HNO3 solution was passed through the LN resin column at a flow rate of 0.5 mL / min using a pipette, syringe pump, or peristaltic pump to obtain the second-stage purified lead-212 simulant Pb product solution.

[0054] A 5 mL second LN resin column was wet-packed. 20 mL of 0.01–0.05 mol / L HNO3 solution was passed through the second LN resin column manually, by syringe, or by peristaltic pump at a flow rate of 0.5 mL / min to obtain the second washing solution. Then, 20 mL of the first-stage purified Actinium-225 mimic La product solution was passed through the second LN resin column at a flow rate of 0.5 mL / min using a pipette, syringe, or peristaltic pump. Next, 50 mL of 0.01 mol / L HNO3 solution was passed through the second LN resin column at a flow rate of 0.5 mL / min using a pipette, syringe, or peristaltic pump to obtain the second waste solution. Finally, 10 mL of 0.5 mol / L HNO3 solution was passed through the second LN resin column at a flow rate of 0.5 mL / min using a pipette, syringe, or peristaltic pump to obtain the second-stage purified Actinium-225 mimic La product solution.

[0055] Example 12

[0056] A method for separating and purifying lead-212 and actinium-225 prepared by photonuclear reaction includes the following steps:

[0057] A 1 mL lead resin column and a 5 mL DGA resin column were packed together using a wet method and connected in series. 40 mL of 3.0 mol / L HNO3 solution was passed sequentially through the lead resin column and the DGA resin column at a flow rate of 0.8 mL / min using a pipette, syringe pump, or peristaltic pump to obtain the first washing solution. Next, 40 mL of simulated irradiation target solution was passed sequentially through the lead resin column and the DGA resin column at a flow rate of 0.8 mL / min using a pipette, syringe pump, or peristaltic pump. The effluent could be used for further separation and purification of lead-212 simulant Pb and actinium-225 simulant La, or as a recovery solution for the recovery of radium-226. Then, the lead resin column and the DGA resin column were separated for the first separation and purification of lead-212 simulant Pb and actinium-225 simulant La, respectively.

[0058] Use a pipette, syringe pump, or peristaltic pump to pass 70 mL of 1.0 mol / L HNO3 solution through a lead resin column at a flow rate of 0.8 mL / min to obtain the first effluent; then use a pipette, syringe pump, or peristaltic pump to pass 40 mL of 0.001 mol / L HNO3 solution through a lead resin column at a flow rate of 0.8 mL / min to obtain the first purified solution of lead-212 simulant Pb.

[0059] Use a pipette, syringe pump, or peristaltic pump to pass 120 mL of 3.0 mol / L HNO3 solution through a DGA resin column at a flow rate of 0.8 mL / min to obtain the second effluent; then use a pipette, syringe pump, or peristaltic pump to pass 40 mL of 0.01 mol / L HNO3 solution through a DGA resin column at a flow rate of 0.8 mL / min to obtain the first purified solution of actinium-225 simulant La.

[0060] A 5 mL LN resin column was wet-packed. 40 mL of 0.01 mol / L HNO3 solution was passed through the LN resin column manually, by syringe pump, or peristaltic pump at a flow rate of 0.8 mL / min to obtain the first washing solution. Then, 40 mL of the first purified lead-212 mimic Pb product solution was passed through the LN resin column at a flow rate of 0.8 mL / min using a pipette, syringe pump, or peristaltic pump. Next, 70 mL of 0.01 mol / L HNO3 solution was passed through the LN resin column at a flow rate of 0.8 mL / min using a pipette, syringe pump, or peristaltic pump to obtain the first waste solution. Finally, 40 mL of 1.0 mol / L HNO3 solution was passed through the LN resin column at a flow rate of 0.8 mL / min using a pipette, syringe pump, or peristaltic pump to obtain the second purified lead-212 mimic Pb product solution.

[0061] A 5 mL second LN resin column was wet-packed. 40 mL of 0.05 mol / L HNO3 solution was passed through the second LN resin column manually, by syringe pump, or peristaltic pump at a flow rate of 0.8 mL / min to obtain the second washing solution. Then, 40 mL of the first-stage purified product solution of Actinium-225 mimic La was passed through the second LN resin column at a flow rate of 0.5 mL / min using a pipette, syringe pump, or peristaltic pump. Next, 70 mL of 0.05 mol / L HNO3 solution was passed through the second LN resin column at a flow rate of 0.8 mL / min using a pipette, syringe pump, or peristaltic pump to obtain the second waste solution. Finally, 40 mL of 1.0 mol / L HNO3 solution was passed through the second LN resin column at a flow rate of 0.8 mL / min using a pipette, syringe pump, or peristaltic pump to obtain the second-stage purified product solution of Actinium-225 mimic La.

[0062] Performance testing

[0063] 1. Based on the similarity in chemical properties between Ba and Ra, and between La and Ac, as well as the similarity in adsorption and desorption performance on separation resins, this invention uses Ba to simulate Ra and La to simulate Ac, and verifies the feasibility and performance of the scheme described in this invention through simulation experiments. The simulated radium target dissolution solution is a mixed solution of Ba, La, and Pb. A mixed solution containing 1g Ba, 50μg Pb, and 50μg La is prepared, and the medium is 20mL of 0.5mol / L HNO3 solution. This solution is used as the simulated target dissolution solution.

[0064] 2. Take the secondary purified product solution from the example, measure the concentration of Pb and La in it using ICP-OES, multiply the concentration of Pb and La by the volume of the secondary purified product solution to obtain the total mass of Pb and La in the product solution, and divide the total mass of Pb and La by the total mass of Pb and La in the prepared target solution to obtain the recovery rate of Pb and La.

[0065] 3. Measure the concentration of Ba in the secondary purified product solution using ICP-OES. Multiply the concentration of Ba by the volume of the product solution to obtain the total mass of Ba in the product solution. Divide the total mass of Ba in the prepared target solution by the total mass of Ba in the product solution to obtain the decontamination coefficient of Ba.

[0066] Lead recovery rate Ba decontamination coefficient La recovery rate Ba decontamination coefficient Example 1 99％ <![CDATA[1×10 7 ]]> 100％ <![CDATA[1×10 7 ]]> Example 2 97％ <![CDATA[1×10 7 ]]> 100％ <![CDATA[1×10 7 <!-- 5 -->]]> Example 3 100％ <![CDATA[1×10 7 ]]> 100％ <![CDATA[1×10 7 ]]> Example 4 98％ <![CDATA[1×10 7 ]]> 100％ <![CDATA[1×10 7 ]]> Example 5 96％ <![CDATA[1×10 7 ]]> 100％ <![CDATA[1×10 7 ]]> Example 6 99％ <![CDATA[1×10 7 ]]> 70％ <![CDATA[1×10 7 ]]> Example 7 99％ <![CDATA[1×10 7 ]]> 100％ <![CDATA[1×10 7 ]]> Example 8 99％ <![CDATA[1×10 7 ]]> 100％ <![CDATA[1×10 7 ]]> Example 9 99％ <![CDATA[1×10 7 ]]> 100％ <![CDATA[1×10 7 ]]> Example 10 99％ <![CDATA[1×10 7 ]]> 100％ <![CDATA[1×10 7 ]]> Example 11 99％ <![CDATA[1×10 7 ]]> 100％ <![CDATA[1×10 7 ]]> Example 12 99％ <![CDATA[1×10 7 ]]> 100％ <![CDATA[1×10 7 ]]>

[0067] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for separating and purifying lead-212 and actinium-225 prepared by photonuclear reaction, characterized in that, Includes the following steps: S1. Pass the radium target dissolution solution sequentially through a lead resin column and a DGA resin column to obtain the recovery solution; S2. The lead resin column is eluted with the first eluent, and then the first desorption solution is introduced into the lead resin column to obtain a lead-212 primary purification solution. S3. Elute the DGA resin column with the second eluent, and then introduce the second desorption solution into the DGA resin column to obtain the first purification solution of Actinium-225; S4. The lead-212 primary purification solution is introduced into the first LN resin column, and the first LN resin column is eluted with the third elution solution to obtain the first waste liquid. Then, the third desorption solution is introduced into the first LN resin column to obtain the lead-212 secondary purification solution. S5. The Actinium-225 primary purification solution is introduced into the second LN resin column, and the second LN resin column is eluted with the fourth elution solution to obtain the second waste liquid. Then, the fourth desorption solution is introduced into the second LN resin column to obtain the Actinium-225 secondary purification product solution. The first rinsing solution is 50-70 mL of 0.1-1.0 mol / L HNO3 solution; The second rinsing solution is 50-120 mL of 0.5-3.0 mol / L HNO3 solution; The third rinsing solution is 20-40 mL of 0.005-0.01 mol / L HNO3 solution; The fourth rinsing solution is 50-70 mL of 0.01-0.05 mol / L HNO3 solution; The first desorption solution is 20~40 mL of 0.0001~0.001 mol / L HNO3 solution; The second desorption solution is 20-40 mL of 0.001-0.01 mol / L HNO3 solution; The third desorption solution is 10~40 mL of 0.5~1.0 mol / L HNO3 solution; The fourth desorption solution is 10~40 mL of 0.5~1.0 mol / L HNO3 solution.

2. The method for separation and purification of lead-212 and actinium-225 prepared by photonuclear reaction according to claim 1, characterized in that, Before step S1, 20-40 mL of 0.5-3.0 mol / L HNO3 solution is passed sequentially through a lead resin column and a DGA resin column to obtain the first washing solution.

3. The method for separation and purification of lead-212 and actinium-225 prepared by photonuclear reaction according to claim 1, characterized in that, The volume of lead resin in the lead resin column is 1 mL; the volume of DGA in the DGA resin column is 5 mL.

4. The method for separation and purification of lead-212 and actinium-225 prepared by photonuclear reaction according to claim 1, characterized in that, The volume of LN resin in the first LN resin column is 5 mL. Before step S4, 20-40 mL of 0.005-0.01 mol / L HNO3 solution is passed through the first LN resin column to obtain the second washing solution.

5. The method for separation and purification of lead-212 and actinium-225 prepared by photonuclear reaction according to claim 1, characterized in that, The volume of LN resin in the second LN resin column is 5 mL. Before step S5, 20-40 mL of 0.01-0.05 mol / L HNO3 solution is passed through the second LN resin column to obtain the third washing solution.

6. The separation and purification method for preparing lead-212 and actinium-225 by photonuclear reaction according to claim 1, wherein in step S4, the volume of the lead-212 primary purification solution is 20-40 mL; and in step S5, the volume of the actinium-225 primary purification solution is 20-40 mL.