Method for simultaneous production of 225ac and 212pb based on accelerator irradiation of 226ra

Abstract

This invention relates to isotope preparation methods, specifically to methods based on accelerator irradiation. 226 Ra was prepared simultaneously 225 Ac and 212 This method for treating Pb addresses the shortcomings of existing technologies, such as the difficulty in obtaining raw materials, the challenge in separating impurities, the complexity of operation, and the high requirements for separation equipment. This invention utilizes a high-power, high-energy electron beam converted into bremsstrahlung bombardment. 226 Ra sample target generation 225 Ra and 224 Ra, 225 Ra is produced through β decay. 225 Ac, 224 Ra is produced through alpha decay. 212 Pb, utilizing 225 Ac and 212 Differences in Pb growth rate and the effects of different resins on Pb growth rate 225 Ac and 212 The difference in Pb adsorption performance has an effect on 225 Ac and 212 Pb was separated to obtain 225 Ac solution and 212 Pb solution improves equipment utilization, reduces production costs, and decreases the amount of radioactive waste.

Description

Technical Field

[0001] This invention relates to isotope preparation methods, specifically to methods based on accelerator irradiation. 226 Ra was prepared simultaneously 225 Ac and 212 Pb's method. Background Technology

[0002] With the continuous updating and development of modern medical technologies for tumor diagnosis and treatment, tumor treatment is moving towards precision targeted therapy. In addition to targeted chemotherapy drugs, targeted radionuclide therapy drugs are receiving increasing attention and have a very promising future. Radioactive isotopes that decay after being released by alpha particles, typically such as... 225 Ac and 212 Pb is rapidly becoming a key area of ​​research in targeted cancer therapy, with preclinical animal studies and preliminary clinical practice yielding very successful results. 225 Ac and 212 Pb has significant advantages for targeted therapy: 1) 225 Ac and 212 Pb has excellent nuclear physical and chemical properties and a short half-life. 225 Ac: 9.9d; 212 Pb: 10.6h), with few side effects. 2) 225 Ac and 212 The average energy of the alpha particles emitted by Pb and its daughters is 6-8 MeV, exhibiting high linear energy transfer (LET) in tissues. The high deposition energy density of high-LET radiation leads to numerous double-strand breaks in the DNA of tumor cells, resulting in a significant killing effect on the DNA within tumor cells. Simultaneously, the effective range is very short (approximately 2-100 micrometers, or within 6-8 cells), with almost no toxic side effects on normal tissues surrounding the tumor target. 3) These radioactive isotopes have good tissue biological effects and can organically bind to peptides with short uptake times and antibodies that are compatible with leukemia cells, forming strong tumor targeting.

[0003] Traditional 225 Ac is from 233 It was extracted from the decay chain of U, and 212 Pb is prepared from large quantities 228 Separation and extraction from Th 212 Pb is uranium. 232 U and 232 Members of the Th decay chain can be derived from... 228 Th(T 1 / 2 =1.9Y) and 224 Ra(T 1 / 2 =3.66d) decays and is produced, and the progeny is removed using a cation exchange column. 212Other nuclides besides Pb are removed by chemical or physical separation, and finally collected by washing with nitric acid or hydrochloric acid. 212 Pb. Both require 233 U and 228 The scarcity of Th sources raises concerns about nuclear material regulation. Furthermore, the complex decay chains and the high cumulative radioactive dose from various intermediate products make experimental operations extremely difficult. This places high demands not only on the material properties of the separation equipment but, more importantly… 225 Ac and 212 Pb production is very low, far from meeting the needs of research and clinical applications. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies, such as the difficulty in obtaining raw materials, the difficulty in separating impurities, the complexity of operation, and the high requirements for separation equipment, by providing a method based on accelerator irradiation. 226 Ra was prepared simultaneously 225 Ac and 212 Pb's method.

[0005] To achieve the above objectives, the technical solution provided by this invention is as follows:

[0006] A method based on accelerator irradiation 226 Ra was prepared simultaneously 225 Ac and 212 The Pb method is unique in that it includes the following steps:

[0007] Step 1: Use the electron beam of an electron accelerator to generate X-rays;

[0008] Step 2: Irradiate with X-rays 226 Ra sample target, respectively generated through nuclear reaction 225 Ra and 224 Ra;

[0009] Step 3: After irradiation 226 The Ra sample target dissolves in an inorganic acid solution;

[0010] Step 4: Evaporate the inorganic acid solution obtained in Step 3 to dryness, dissolve the residue in the inorganic acid solution to obtain solution A, let it stand for 1-3 days, and then transfer it to a resin chromatography column; the resin chromatography column is an Sr resin chromatography column or a Pb resin chromatography column.

[0011] Step 5: Wash the resin chromatography column with an inorganic acid solution and collect the eluent; the inorganic acid is the same as that in Step 4.

[0012] Step 6: Separation and purification 212 Pb

[0013] The resin chromatography column was washed again with an inorganic acid solution, and the effluent was the first radioactive waste liquid. A first cation exchange resin chromatography column was then connected to the lower end of the resin chromatography column. Both the resin chromatography column and the first cation exchange resin column were washed with a mixed solution of citric acid and sodium chloride, and the effluent was collected as the waste liquid. 212 Pb solution;

[0014] Step 7: Separation and purification 225 Ac

[0015] The effluent from step 5 is allowed to stand for 15-20 days, evaporated to dryness, and the residue is dissolved in an inorganic acid solution and transferred to a second cation exchange resin chromatography column. The column is then washed with perchloric acid solution, and the collected effluent is the second radioactive waste liquid. The column is then washed again with an inorganic acid solution, and the collected effluent is the second radioactive waste liquid. 225 Ac solution.

[0016] Furthermore, the concentration of the inorganic acid solution in step 3 is 9 ± 1 mol / L;

[0017] The concentration of the inorganic acid solution in steps 4 and 5 is 3 ± 1 mol / L;

[0018] The volume of the inorganic acid solution in step 5 is 2-4 times the volume of the resin chromatography column;

[0019] In step 6, the concentration of the inorganic acid solution used to wash the resin chromatography column again is 0.1±0.01mol / L, and the volume is 10-20 times the volume of the resin chromatography column.

[0020] The concentrations of citric acid and sodium chloride in the mixed solution are 0.05±0.01mol / L and 0.5±0.05mol / L, respectively; the pH of the mixed solution is 4.0±0.5, and its volume is 10-20 times the volume of the resin chromatography column.

[0021] In step 7, the concentration of the inorganic acid solution used to dissolve the residue is 0.1 ± 0.01 mol / L;

[0022] The concentration of the perchloric acid is 9±1 mol / L, and its volume is 2-4 times the volume of the second cation exchange resin chromatography column.

[0023] The concentration of the inorganic acid solution used to wash the second cation exchange resin chromatography column is 5±1 mol / L, and its volume is 2-4 times the volume of the second cation exchange resin chromatography column.

[0024] Furthermore, in steps 3 to 7, the inorganic acid solution is a hydrochloric acid solution or a nitric acid solution.

[0025] Furthermore, in step 1, the electron beam energy is greater than 25 MeV; the irradiation time is 5-10 days;

[0026] In step 3, the inorganic acid solution is a hydrochloric acid solution;

[0027] In steps 4 and 5, the inorganic acid solution is a nitric acid solution;

[0028] In step 6, the inorganic acid used to wash the resin chromatography column again is hydrochloric acid solution; the first cation exchange resin chromatography column is a 50W×8 chromatography column;

[0029] In step 7, the inorganic acid used to dissolve the residue is hydrochloric acid solution, and the inorganic acid used to wash the second cation exchange resin chromatography column is nitric acid solution; the second cation exchange resin chromatography column is a Dowex-50 chromatography column.

[0030] In addition, a method based on accelerator irradiation is also provided. 226 Ra was prepared simultaneously 225 Ac and 212 The Pb method is unique in that it includes the following steps:

[0031] Step 1: Use the electron beam of an electron accelerator to generate X-rays;

[0032] Step 2: Irradiate with X-rays 226 Ra sample target, respectively generated through nuclear reaction 225 Ra and 224 Ra;

[0033] Step 3: After irradiation 226 The Ra sample target dissolves in an inorganic acid solution;

[0034] Step 4: Evaporate the inorganic acid solution obtained in Step 3 to dryness, dissolve the residue in the inorganic acid solution to obtain solution A, let it stand for 1-3 days, and then transfer it to a resin chromatography column; the resin chromatography column is a Pb resin chromatography column or an Sr resin chromatography column.

[0035] Step 5: Wash the resin chromatography column with an inorganic acid solution and collect the eluent;

[0036] Step 6: Separation and purification 212 Pb

[0037] The resin chromatography column was washed again with an inorganic acid solution, and the effluent was the first radioactive waste liquid. A first cation exchange resin chromatography column was then connected to the lower end of the resin chromatography column. Both the resin chromatography column and the first cation exchange resin column were washed with a mixed solution of citric acid and sodium chloride, and the effluent was collected as the waste liquid. 212 Pb solution;

[0038] Step 7: Let the eluent from Step 5 stand for 2-4 days before adding it to the resin chromatography column;

[0039] Step 8: Repeat steps 5, 6 and 7 at least 4 times, so that the total settling time of the effluent in step 5 is 15-20 days. Then, evaporate the effluent obtained in the last step 5 to dryness to obtain the corresponding residue.

[0040] Step 9: Separation and purification 225 Ac

[0041] The residue was dissolved in an inorganic acid solution and transferred to a second cation exchange resin chromatography column. The second cation exchange resin chromatography column was washed with perchloric acid solution, and the effluent was collected as the second radioactive waste liquid. The second cation exchange resin chromatography column was then washed again with an inorganic acid solution, and the effluent was collected as the waste liquid. 225 Ac solution.

[0042] Furthermore, it also includes step 10, recycling the second radioactive waste liquid 3-5 times:

[0043] The second radioactive waste liquid from step 9 is allowed to stand for 15-20 days, then evaporated to dryness to obtain residue. The residue is then recycled to step 9 for separation. 225 Ac solution and corresponding second radioactive waste liquid; circulate 3-5 times, collecting the results from each cycle. 225 Ac solution and the resulting second radioactive waste liquid.

[0044] Furthermore, the concentration of the inorganic acid solution in step 3 is 9 ± 1 mol / L;

[0045] The concentration of the inorganic acid solution in steps 4 and 5 is 3 ± 1 mol / L;

[0046] The volume of the inorganic acid solution in step 5 is 2-4 times the volume of the resin chromatography column;

[0047] In step 6, the concentration of the inorganic acid solution used to wash the resin chromatography column again is 0.1±0.01mol / L, and the volume is 10-20 times the volume of the resin chromatography column.

[0048] The concentrations of citric acid and sodium chloride in the mixed solution are 0.05±0.01mol / L and 0.5±0.05mol / L, respectively; the pH of the mixed solution is 4.0±0.5, and its volume is 10-20 times the volume of the resin chromatography column.

[0049] In step 9, the concentration of the inorganic acid solution used to dissolve the residue is 0.1 ± 0.01 mol / L;

[0050] The concentration of the perchloric acid is 9±1 mol / L, and its volume is 2-4 times the volume of the second cation exchange resin chromatography column.

[0051] The concentration of the inorganic acid solution used to wash the second cation exchange resin chromatography column is 5±1 mol / L, and its volume is 2-4 times the volume of the second cation exchange resin chromatography column.

[0052] Furthermore, in steps 3, 4, 5, 6, and 9, the inorganic acid solution is a hydrochloric acid solution or a nitric acid solution.

[0053] Furthermore, in step 1, the electron beam energy is 25 MeV ≤ 70 MeV; the irradiation time is 5-10 days.

[0054] In step 3, the inorganic acid solution is a hydrochloric acid solution;

[0055] In steps 4 and 5, the inorganic acid solution is a nitric acid solution;

[0056] In step 6, the inorganic acid used to wash the resin chromatography column again is hydrochloric acid solution; the first cation exchange resin chromatography column is a 50W×8 chromatography column;

[0057] In step 9, the inorganic acid used to dissolve the residue is hydrochloric acid solution, and the inorganic acid used to wash the second cation exchange resin chromatography column is nitric acid solution; the second cation exchange resin chromatography column is a Dowex-50 chromatography column.

[0058] Compared with the prior art, the present invention has the following beneficial effects:

[0059] 1. The raw materials used in this invention are 226 Ra, the raw materials for production are readily available, and it generates little radioactive waste; through bombardment... 226 Ra sample target simultaneously generates 225 Ac and 212 Pb, and then using different resins to treat 225 Ac and 212 The differences in the adsorption properties of Pb allow for their separation, 226 Two medical isotopes can be separated from the Ra sample target after a single irradiation, which improves the utilization rate of the device and reduces production costs.

[0060] 2. In step 6.2 of this invention, during the settling process of the effluent, the process returns to step 5 every 2-4 days for repeated treatment, making full use of the... 224 Ra; then the second radioactive waste liquid is recycled to make it... 225 Ra was fully utilized, and the resulting second radioactive waste liquid mainly contained 226 Ra, which can be used for recycling 226 Ra can be reused and effectively improved. 212 Pb solution and 225 The production of Ac solution is reduced, thus decreasing radioactive waste. Attached Figure Description

[0061] Figure 1 This is a flowchart of the preparation process in Embodiment 1 of the present invention;

[0062] Figure 2 This is in Embodiment 1 of the present invention 225 Ac's α spectrum;

[0063] Figure 3 This is in Embodiment 1 of the present invention 226 Ra after irradiation 225 Ra、 224 The decay of Ra and 212 Pb, 209 Pb generation relationship diagram;

[0064] Figure 4 This is the repeated separation in Embodiment 1 of the present invention. 225 Ac time spectrum. Detailed Implementation

[0065] Example 1

[0066] This invention is based on accelerator irradiation 226 Ra was prepared simultaneously 225 Ac and 212 The Pb method utilizes high-power, high-energy electron beams converted into bremsstrahlung bombardment. 226 Ra sample target can simultaneously generate 225 Ac and 212 Pb, this method utilizes 225 Ac and 212 Differences in Pb growth rate and the effects of different resins on Pb growth rate 225 Ac and 212 The difference in Pb adsorption performance was first investigated by extracting Pb from the target solution using a Pb-specific resin. 212 Pb was then extracted using a cation exchange resin. 225 Ac, achieving the goal of obtaining two medical isotopes in a single irradiation, thereby improving equipment utilization and reducing production costs. Among them, 212 Pb and 225 The formation reaction of Ac is as follows:

[0067]

[0068]

[0069] The preparation flowchart of this method is as follows: Figure 1 As shown, it includes the following steps:

[0070] Step 1: Use an electron beam with an energy of 40 MeV from an electron accelerator to generate X-rays;

[0071] Among them, the electron beam energy is 25MeV≤70MeV, preferably 40MeV.

[0072] Step 2: Irradiate with X-rays 226 Ra sample target 9 days 226 Ra sample target via nuclear reaction 226 Ra(γ,n) is generated 225 Ra, at the same time 226 Ra sample target via nuclear reaction 226 Ra(γ, 2n) is generated 224 Ra;

[0073] Irradiation time is typically 5-10 days, depending on the required product quantity; a small amount of decay reaction occurs during irradiation. 225 Ra decays via β. 225 Ac, 224 Ra is generated through 3 α decays. 212 Pb;

[0074] Step 3: After irradiation 226 The Ra sample target is dissolved in a hydrochloric acid solution; the concentration of the hydrochloric acid solution is 9±1 mol / L, and the volume of the hydrochloric acid solution is determined according to the mass of the sample target to ensure complete dissolution of the sample target;

[0075] Step 4: Evaporate the above hydrochloric acid solution to dryness, and dissolve the residue in 3 mL of nitric acid solution to obtain solution A; after letting solution A stand for 3 days, transfer it to an Sr resin chromatography column;

[0076] The nitric acid solution concentration is 3±1 mol / L, and the volume is 2-5 mL. The volume of the nitric acid solution is adjusted according to the amount of residue to ensure complete dissolution. The standing time is usually 2-4 days. 224 Ra is generated through 3 α decays. 212 Pb, both too long and too short a time will cause 212 The decrease in Pb content in products, such as Figure 3 As shown 226 After Ra is irradiated 225 Ra、 224 The decay of Ra and 212 Pb, 209 The generation relationship diagram of Pb.

[0077] Step 5: Wash the Sr resin chromatography column with 2 mL of nitric acid solution and collect the eluent; the concentration of the nitric acid solution used to wash the Sr resin chromatography column is 3 ± 1 mol / L.

[0078] A good effect is achieved when the volume of nitric acid solution is about 2-4 times the volume of the Sr resin chromatography column, which is usually 2-4 mL.

[0079] Step 6: Separation and purification

[0080] 6.1. Separation and purification 212 Pb

[0081] The Sr resin chromatography column was washed again with 10 mL of hydrochloric acid solution, and the effluent was the first radioactive waste liquid; the concentration of the hydrochloric acid solution was 0.1 ± 0.01 mol / L.

[0082] Next, connect a first cation exchange resin chromatography column to the lower end of the Sr resin chromatography column. Wash both the Sr resin chromatography column and the first cation exchange resin chromatography column with a mixed solution of 10 mL of citric acid and sodium chloride. Collect the eluent as [the eluent]. 212 Pb solution;

[0083] In this invention, the volume of the hydrochloric acid solution is approximately 10-20 times the volume of the Sr resin chromatography column, approximately 10-20 mL. The concentration of citric acid in the mixed solution is 0.05 ± 0.01 mol / L, the concentration of sodium chloride is 0.5 ± 0.05 mol / L, the pH of the mixed solution is 4.0 ± 0.5, and the volume is 10-20 mL, approximately 10-20 times the volume of the Sr resin chromatography column.

[0084] The first cation exchange resin chromatography column is a 50W×8 chromatography column or other cation exchange columns with similar performance.

[0085] 6.2. Separation and Purification 225 Ac

[0086] The effluent from step 5 was allowed to stand for 16 days, evaporated to dryness, and the residue was dissolved in hydrochloric acid solution and transferred to a second cation exchange resin chromatography column. The column was then washed with 10 mL of perchloric acid to remove Al, Fe, Mg, Ra, Pa, Po, Pb, and Bi. The collected effluent was the second radioactive waste liquid. The column was then washed with 10 mL of nitric acid solution, and the collected effluent was the second radioactive waste liquid. 225 Ac solution.

[0087] The second cation exchange resin chromatography column is a Dowex-50 column or other cation exchange columns with similar performance. The hydrochloric acid solution used to dissolve the residue has a concentration of 0.1 ± 0.01 mol / L and a volume of 2-5 mL, ensuring complete dissolution. The perchloric acid solution has a concentration of 9 ± 1 mol / L and a volume of 5-10 mL, approximately 2-4 times the volume of the second cation exchange resin chromatography column. The nitric acid solution used to wash the second cation exchange resin chromatography column has a concentration of 5 ± 1 mol / L and a volume of 5-10 mL, approximately 2-4 times the volume of the second cation exchange resin chromatography column.

[0088] The settling time can be 15-20 days, so that225 Ra decays via β. 225 Ac, too long a time will cause 225 If the reduction in Ac product content occurs within too short a time, a small amount will still remain in the effluent. 224 s and their products 212 Pb and other pollutants cause interference, and the time is approximately 15-20 days. 224 The Ra half-life is 5 times that of 3.66 days, at which point the vast majority of... 224 Ra has completely decayed.

[0089] In this invention, the Sr resin in the Sr resin chromatography column has a particle size of 50-100 μm and an effective column volume of 500-1000 μL, and is packed using the sedimentation method. The cation exchange resin in the first cation exchange resin chromatography column has a particle size of 100-150 μm and an effective column volume of 500-1000 μL, and is packed using the sedimentation method. The cation exchange resin in the second cation exchange resin chromatography column has a particle size of 200 mesh and an effective column volume of 500-2000 μL, and is packed using the sedimentation method. The smaller the Sr resin particle size and the smaller the cation exchange resin mesh size, the better the adsorption performance of the same mass of resin. However, too small a resin size creates too much resistance to the liquid flow, affecting the liquid flow rate and increasing the separation time. Therefore, it is necessary to select suitable particle size and mesh size to achieve better results.

[0090] In other embodiments of the present invention, the hydrochloric acid solution and nitric acid solution can be replaced by other inorganic acid solutions, and the Sr resin chromatography column can be replaced by a Pb resin chromatography column.

[0091] Using a resolution of 16 keV and an active area of ​​0.6 cm² 2 The αSi(Au) detector for the final product 225 Alpha ray measurements were performed using an Ac solution. The solution was coated onto a stainless steel substrate. 225 Ac solution, then evaporate 225 An Ac solution was used to prepare an α sample, and the α sample was measured to obtain its α spectrum, as shown below. Figure 2 As shown, it can be seen 225 The four α-decaying nuclides in the Ac decay chain are clearly defined, with energies Eα(Eα, ... 225 Ac)=5.8MeV,Eα( 221 Fr)=6.3MeV, Eα( 217 At) = 7.1 MeV, Eα( 213 Po) = 8.4 MeV, and no other α-decay nuclides were observed in the figure, indicating that the nuclide obtained in this invention... 225 Ac has a high purity, meeting the requirements.

[0092] The effluent from step 5 contains 226 Ra、 225 Ra and224 Ra, in step 6.2, is left to stand for 15-20 days to remove it. 224 Ra; where, after standing for 2-4 days, 224 Ra decay produces 212 Therefore, during the 15-20 day settling period, it is transferred to the Sr resin chromatography column every 2-4 days, and returned to step 5 for processing, collecting the generated Pb. 212 Pb, thereby increasing 212 The production of Pb solution, after being repeated at least 4 times, involves a total settling time of 15-20 days for the effluent before proceeding to step 6.2. At this point, the second radioactive waste liquid obtained in step 6.2 contains... 226 Ra and 225 Ra; Figure 4 When the effluent from step 5 is allowed to stand, its components... 225 Ac and 225 The separation time spectrum of Ra, based on this change, shows that approximately every 15-20 days... 225 Ac activity tends to stabilize after 20 days. 225 Ac activity actually tends to decrease, therefore according to Figure 4 In step 6.2, after the effluent is allowed to stand for about 15-20 days for separation, the resulting second radioactive waste liquid is used to replace the effluent from step 5. This process of step 6.2 is repeated 3-5 times to remove the radioactive waste liquid from the final product. 225 Ra activity was reduced to a minimum, making its main component... 226 Ra can be used for 226 The recycling and reuse of Ra, while collecting the waste generated in each cycle. 225 Ac solution, effectively improves 225 The yield of Ac solution.

[0093] Example 2

[0094] This invention is based on accelerator irradiation 226 Ra was prepared simultaneously 225 Ac and 212 Pb's method includes the following steps:

[0095] Step 1: Use the electron beam from an electron accelerator to generate X-rays; the electron beam energy is 35 MeV.

[0096] Step 2: Irradiate with X-rays 226 Ra sample target 5 days 226 Ra sample target via nuclear reaction 226 Ra(γ,n) is generated 225 Ra, 226 Ra sample target via nuclear reaction 226 Ra(γ, 2n) is generated224 Ra;

[0097] Step 3: After irradiation 226 The Ra sample target dissolves in hydrochloric acid solution;

[0098] Step 4: Evaporate the above hydrochloric acid solution to dryness, and dissolve the residue in 2 mL of hydrochloric acid solution to obtain solution A;

[0099] Step 5: After letting solution A stand for 3 days, transfer it to an Sr resin chromatography column, wash the Sr resin chromatography column with 3 mL of hydrochloric acid solution, and collect the eluent.

[0100] Step 6: Separation and purification

[0101] 6.1. Wash the Sr resin chromatography column again with 14 mL of hydrochloric acid solution. The effluent is the first radioactive waste liquid.

[0102] Next, connect a first cation exchange resin chromatography column to the lower end of the Sr resin chromatography column. Wash both the Sr resin chromatography column and the first cation exchange resin chromatography column with a mixed solution of 14 mL of citric acid and sodium chloride. Collect the eluent as [the eluent]. 212 Pb solution;

[0103] 6.2. The effluent from step 5 was allowed to stand for 15 days, evaporated to dryness, and the residue was dissolved in hydrochloric acid solution and transferred to a second cation exchange resin chromatography column. The column was then washed with 7 mL of perchloric acid to remove Al, Fe, Mg, Ra, Pa, Po, Pb, and Bi. The collected effluent was the second radioactive waste liquid. The column was then washed with 7 mL of nitric acid solution, and the collected effluent was the second radioactive waste liquid. 225 Ac solution.

[0104] Example 3

[0105] This invention is based on accelerator irradiation 226 Ra was prepared simultaneously 225 Ac and 212 Pb's method includes the following steps:

[0106] Step 1: Use the electron beam from an electron accelerator to generate X-rays; the electron beam energy is 70 MeV.

[0107] Step 2: Irradiate with X-rays 226 Ra sample target 8 days 226 Ra sample target via nuclear reaction 226 Ra(γ,n) is generated 225 Ra, 226 Ra sample target via nuclear reaction 226 Ra(γ, 2n) is generated 224 Ra;

[0108] Step 3: After irradiation 226 The Ra sample target dissolves in hydrochloric acid solution;

[0109] Step 4: Evaporate the above hydrochloric acid solution to dryness, and dissolve the residue in 5 mL of nitric acid solution to obtain solution A;

[0110] Step 5: After letting solution A stand for 2 days, transfer it to an Sr resin chromatography column, wash the Sr resin chromatography column with 4 mL of nitric acid solution, and collect the eluent.

[0111] Step 6: Separation and purification

[0112] 6.1. Wash the Sr resin chromatography column again with 20 mL of nitric acid solution; the effluent is the first radioactive waste liquid.

[0113] Next, connect a first cation exchange resin chromatography column to the lower end of the Sr resin chromatography column. Wash both the Sr resin chromatography column and the first cation exchange resin chromatography column with a mixed solution of 20 mL of citric acid and sodium chloride. Collect the eluent as [the eluent]. 212 Pb solution;

[0114] 6.2. The effluent from step 5 was allowed to stand for 20 days, evaporated to dryness, and the residue was dissolved in hydrochloric acid solution and transferred to a second cation exchange resin chromatography column. The column was then washed with 8 mL of perchloric acid to remove Al, Fe, Mg, Ra, Pa, Po, Pb, and Bi. The collected effluent was the second radioactive waste liquid. The second cation exchange resin chromatography column was washed with 8 mL of hydrochloric acid solution, and the collected effluent was the second radioactive waste liquid. 225 Ac solution.

[0115] Example 4

[0116] This invention is based on accelerator irradiation 226 Ra was prepared simultaneously 225 Ac and 212 Pb's method includes the following steps:

[0117] Step 1: Use the electron beam from an electron accelerator to generate X-rays; the electron beam energy is 25 MeV.

[0118] Step 2: Irradiate with X-rays 226 Ra sample target 10 days, 226 Ra sample target via nuclear reaction 226 Ra(γ,n) is generated 225 Ra, at the same time 226 Ra sample target via nuclear reaction 226 Ra(γ, 2n) is generated 224 Ra;

[0119] Step 3: After irradiation226 The Ra sample target dissolves in hydrochloric acid solution;

[0120] Step 4: Evaporate the above hydrochloric acid solution to dryness, and dissolve the residue in 5 mL of nitric acid solution to obtain solution A;

[0121] Step 5: After letting solution A stand for 3 days, transfer it to an Sr resin chromatography column, wash the Sr resin chromatography column with 3.5 mL of nitric acid solution, and collect the eluent.

[0122] Step 6: Separation and purification

[0123] 6.1. Wash the Sr resin chromatography column again with 16 mL of hydrochloric acid solution. The effluent is the first radioactive waste liquid.

[0124] Next, connect a first cation exchange resin chromatography column to the lower end of the Sr resin chromatography column. Wash both the Sr resin chromatography column and the first cation exchange resin chromatography column with a mixed solution of 16 mL of citric acid and sodium chloride. Collect the eluent. 212 Pb solution;

[0125] 6.2. The effluent from step 5 was allowed to stand for 18 days, evaporated to dryness, and the residue was dissolved in hydrochloric acid solution and transferred to a second cation exchange resin chromatography column. The column was then washed with 9 mL of perchloric acid to remove Al, Fe, Mg, Ra, Pa, Po, Pb, and Bi. The collected effluent was the second radioactive waste liquid. The second cation exchange resin chromatography column was washed with 9 mL of hydrochloric acid solution, and the collected effluent was... 225 Ac solution.

[0126] Example 5

[0127] This invention is based on accelerator irradiation 226 Ra was prepared simultaneously 225 Ac and 212 Pb's method includes the following steps:

[0128] Step 1: Use the electron beam of an electron accelerator to generate X-rays; the electron beam energy is 55 MeV;

[0129] Step 2: Irradiate with X-rays 226 Ra sample target 7 days 226 Ra sample target via nuclear reaction 226 Ra(γ,n) is generated 225 Ra, at the same time 226 Ra sample target via nuclear reaction 226 Ra(γ, 2n) is generated 224 Ra;

[0130] Step 3: After irradiation 226 The Ra sample target dissolves in hydrochloric acid solution;

[0131] Step 4: Evaporate the above hydrochloric acid solution to dryness, and dissolve the residue in 4 mL of nitric acid solution to obtain solution A;

[0132] Step 5: After letting solution A stand for 1 day, transfer it to an Sr resin chromatography column, wash the Sr resin chromatography column with 3 mL of nitric acid solution, and collect the eluent.

[0133] Step 6: Separation and purification

[0134] 6.1. Wash the Sr resin chromatography column again with 13 mL of hydrochloric acid solution. The effluent is the first radioactive waste liquid.

[0135] Next, connect a first cation exchange resin chromatography column to the lower end of the Sr resin chromatography column. Wash both the Sr resin chromatography column and the first cation exchange resin chromatography column with a mixed solution of 12 mL of citric acid and sodium chloride. Collect the eluent. 212 Pb solution;

[0136] 6.2. The effluent from step 5 was allowed to stand for 16 days, evaporated to dryness, and the residue was dissolved in hydrochloric acid solution and transferred to a second cation exchange resin chromatography column. The column was then washed with 5 mL of perchloric acid to remove Al, Fe, Mg, Ra, Pa, Po, Pb, and Bi. The collected effluent was the second radioactive waste liquid. The column was then washed with 5 mL of nitric acid solution, and the collected effluent was the second radioactive waste liquid. 225 Ac solution.

Claims

1. A method based on accelerator irradiation 226 Ra was prepared simultaneously 225 Ac and 212 The method for Pb is characterized by, Includes the following steps: Step 1: Use the electron beam of an electron accelerator to generate X-rays; 25 MeV ≤ electron beam energy ≤ 70 MeV; Step 2: Irradiate with X-rays 226 Ra sample target, respectively generated through nuclear reaction 225 Ra and 224 Ra; irradiation time is 5-10 days; Step 3: After irradiation 226 The Ra sample target dissolves in an inorganic acid solution; Step 4: Evaporate the inorganic acid solution obtained in Step 3 to dryness, dissolve the residue in the inorganic acid solution to obtain solution A, let it stand for 1-3 days, and then transfer it to a resin chromatography column. The resin chromatography column is a Pb resin chromatography column or a Sr resin chromatography column; Step 5: Wash the resin chromatography column with an inorganic acid solution and collect the eluent; Step 6: Separation and purification 212 Pb The resin chromatography column was washed again with an inorganic acid solution, and the effluent was the first radioactive waste liquid. Next, connect a first cation exchange resin chromatography column to the lower end of the resin chromatography column. Wash both the resin chromatography column and the first cation exchange resin column with a mixed solution of citric acid and sodium chloride, and collect the effluent. 212 Pb solution; Step 7: Let the eluent from Step 5 stand for 2-4 days before adding it to the resin chromatography column; Step 8: Repeat steps 5, 6 and 7 at least 4 times, so that the total settling time of the effluent in step 5 is 15-20 days. Then, evaporate the effluent obtained in the last step 5 to dryness to obtain the corresponding residue. Step 9: Separation and purification 225 Ac The residue was dissolved in an inorganic acid solution and transferred to a second cation exchange resin chromatography column. The second cation exchange resin chromatography column was washed with perchloric acid solution, and the effluent was collected as the second radioactive waste liquid. The second cation exchange resin chromatography column was then washed again with an inorganic acid solution, and the effluent was collected as the waste liquid. 225 Ac solution.

2. The accelerator irradiation-based method according to claim 1 226 Ra was prepared simultaneously 225 Ac and 212 The method for Pb is characterized by: It also includes step 10, which involves recycling the second radioactive waste liquid 3-5 times: The second radioactive waste liquid from step 9 is allowed to stand for 15-20 days, then evaporated to dryness to obtain residue. The residue is then recycled to step 9 for separation. 225 Ac solution and corresponding second radioactive waste liquid; circulate 3-5 times, collecting the results from each cycle. 225 Ac solution and the resulting second radioactive waste liquid.

3. The accelerator irradiation-based method according to claim 2 226 Ra was prepared simultaneously 225 Ac and 212 The method for Pb is characterized by: The concentration of the inorganic acid solution in step 3 is 9 ± 1 mol / L; The concentration of the inorganic acid solution in steps 4 and 5 is 3 ± 1 mol / L; The volume of the inorganic acid solution in step 5 is 2-4 times the volume of the resin chromatography column; In step 6, the concentration of the inorganic acid solution used to wash the resin chromatography column again is 0.1 ± 0.01 mol / L, and the volume is 10-20 times the volume of the resin chromatography column. The concentrations of citric acid and sodium chloride in the mixed solution are 0.05±0.01 mol / L and 0.5±0.05 mol / L, respectively; the pH of the mixed solution is 4.0±0.5, and its volume is 10-20 times the volume of the resin chromatography column. In step 9, the concentration of the inorganic acid solution used to dissolve the residue is 0.1 ± 0.01 mol / L; The concentration of the perchloric acid is 9 ± 1 mol / L, and its volume is 2-4 times the volume of the second cation exchange resin chromatography column. The concentration of the inorganic acid solution used to wash the second cation exchange resin chromatography column is 5±1 mol / L, and its volume is 2-4 times the volume of the second cation exchange resin chromatography column.

4. The accelerator irradiation-based method according to claim 3 226 Ra was prepared simultaneously 225 Ac and 212 The method for Pb is characterized by: In steps 3, 4, 5, 6, and 9, the inorganic acid solution is a hydrochloric acid solution or a nitric acid solution.

5. The accelerator irradiation-based method according to claim 4 226 Ra was prepared simultaneously 225 Ac and 212 The method for Pb is characterized by: In step 3, the inorganic acid solution is a hydrochloric acid solution; In steps 4 and 5, the inorganic acid solution is a nitric acid solution; In step 6, the inorganic acid used to wash the resin chromatography column again is hydrochloric acid solution; the first cation exchange resin chromatography column is a 50 W × 8 column; In step 9, the inorganic acid used to dissolve the residue is hydrochloric acid solution, and the inorganic acid used to wash the second cation exchange resin chromatography column is nitric acid solution. The second cation exchange resin chromatography column is a Dowex-50 chromatography column.

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