The invention relates to the field of production of radioactive isotopes, namely to obtain radionuclide palladium-103 cyclotron using a beam of charged particles.

A method of obtaining palladium-103 radiation palladium enriched in palladium-102, the neutron flux in a nuclear reactor (U.S. Patent No. 4702228, NCI 600/8. Interstitial implants, emitting x-rays. Published 27.10.1987). But such sources have several disadvantages, due to the method of obtaining palladium-103. The disadvantages of the method of obtaining palladium-103 in a nuclear reactor are relatively low specific activity (up to 100 MCI/mg)as only a small part of the atoms of the irradiated material enters the target radionuclide. Currently, the maximum degree of enrichment of palladium-102 reaches only 70 or 80%, due to the presence of other isotopes of palladium formed radionuclides palladium-101 and palladium-109, which cannot be separated by chemical means. Before using palladium-103 needed exposure for the decay of other radionuclides palladium, which leads to the loss of the radionuclide palladium-103 due to radioactive decay over time. In addition, by irradiating form radionuclides with other elements such as silver-111, the separation of which is difficult the task is. If you use the micro sources without treatment from silver-111, it will lead to additional radiation absorbed dose. The disadvantages include the relatively high cost of the product, due mainly to the significant cost of obtaining highly enriched palladium-102.

A method of obtaining palladium-103, which consists in irradiation on the accelerator targets of enriched isotope Pd-104, Pd-105, Pd-106, or a mixture thereof protons or deuterons with energies of 10-50 MeV (U.S. Patent No. 6143431, NCI 428/669; IPC G21G 1/10. Obtaining palladium-103. Published 07.11.2000). The disadvantages of this method are:

- low specific activity of the product (less than 100 MCI/mg), which limits its validity for the manufacture of micro sources;

- loss of the radionuclide palladium-103 due to the need for exposure after exposure of the target for 19 days for decay of the impurity radionuclides palladium-100 and palladium-101;

- multi-stage purification technology palladium-103 from impurities.

A method of obtaining a radionuclide, palladium-103 with high specific activity (U.S. Patent No. 5405309, NCI 600/3; IPC A61N005/00. Interstitial x-ray emitter. Published 11.04.1995). The method consists in the irradiation of the target on the accelerator and subsequent radiochemical processing with the aim of obtaining pure palladium-103. The target is the Wallpaper of the copper substrate, on which the electrolytic method applied layer of metallic rhodium (˜ 2 g). The resulting target is irradiated on the accelerator protons or deuterons with energy, after which the rhodium is only one isotope of palladium - palladium-103, i.e. palladium-103 is virtually no media. Processing the target consists of the following stages:

a) metal rhodium pre mechanically perforined and then separated from the substrate by dissolving the latter, for example, in nitric acid to obtain a solution containing flakes of rhodium;

b) scales rhodium extract on filter paper, washed. Filter with rhodium placed in a muffle furnace and heated to decomposition filter;

C) scales rhodium alloy in a muffle furnace with NaHSO₄. The formation of soluble in dilute hydrochloric acid salt of rhodium. For the complete dissolution of rhodium operation is repeated several times;

g) in a solution containing a salt of rhodium, add palladium-media and carry out the selection of palladium-103 from a solution on a column of anion exchange resin. Palladium-103 elute from the column with a solution of NH₄OH. Palladium-carrier added to the original solution of rhodium to reduce losses of palladium-103 when it is clean.

As shown by the experiments of the authors of the proposed technical solution, thoroughly washed from the column palladium-103 without media now is tenderly and up to 50% of the activity of a radionuclide remain on the column. Apparently, this is due to the recovery of palladium. Recovery of palladium on organic sorbents were also reported in the work Burmistrova NM (Burmistrova NM the complexation of palladium sorption processes. Abstract. descend. chem. Sciences. St. Petersburg, 2000). The main disadvantages of this process are the high complexity of the process and use multihreading operations (filtering, sintering in a muffle furnace), and adding palladium carrier, which reduces the shelf life of the product for the manufacture of micro sources.

Closest to the proposed technical solution is a method for palladium-103 without media (Viewing and other Receiving palladium-103 without media and preparation of radioactive colloidal drug palladium for medical purposes. / / radiochemistry. 1971. Vol.13, issue 4, s-627.), which consists in irradiation of metallic rhodium protons or deuterons accelerated in a cyclotron, the electrochemical dissolution of the irradiated target and subsequent chemical selection of palladium-103. The target consisted of a copper substrate, to which the diffusion-welded plate of metallic rhodium. The separation of rhodium was carried out by dissolving the copper substrate in nitric acid. Then rhodium was dissolved in 6 M hydrochloric acid using displacement is tion current. The solution was diluted to 1 M HCl solution was added to dimethylglyoxime and was extracted with palladium-103 in chloroform as dimethylglyoximate. The chloroform was evaporated to dryness, the resulting residue was repeatedly treated with Imperial vodka and hydrogen peroxide to decompose organic substances. After the decomposition of organic substances, the solution was evaporated to dryness and the residue was dissolved in 0.5 M HCl by heating. The described method was tested by the authors of the proposed technical solution to obtain small amounts of palladium-103 (100 MCI). In the processing of high-level targets (activity in target a few dozen Curie) identified the following disadvantages of the method:

1) during long-term irradiation of the target to obtain large quantities of palladium-103 from structural materials, the particles on the target surface is deposited iron, which then formed the radionuclide cobalt-56, which diffuses into the material of the target is rhodium. In addition, rhodium welded to the copper substrate by the method of diffusion welding. Therefore, by dissolving the substrate in nitric acid cannot be completely removed from rhodium iron, copper and formed from them during irradiation in a cyclotron radionuclides, and the presence of iron and copper leads to instability of the extraction process (significant fluctuation of yield);

2) cannot also be totally the Yu remove organic matter. As a result, the receipt of the product in a small amount of a precipitate, and in some cases a thin transparent polymer film, which complicates the process of evaporation of the solution to dryness to palladium-103 in commercial form.

Apparently, this is due to the fact that during extraction the selection of palladium-103 uses significant amounts of organic substances: chloroform - up to 1 l and dimethylglyoxime ˜ 0,5-0,6, Evaporation of the chloroform takes a long time, so in the presence of chloroform, palladium-103 (several tens of curies possible the processes of polymerization with the formation of recalcitrant compounds. The above degrades the quality of the product and creates problems when using it. To eliminate this drawback it is necessary to reduce the amount of organic matter applied in the process of selection of the radionuclide, and to reduce the time of contact of organic substances with radioactive substances.

The authors goal was to eliminate the mentioned disadvantages and to develop a method of obtaining a radionuclide palladium-103 without media, providing large quantities of palladium-103 high quality, and also increase the yield of the target product and to increase the stability of the process.

To solve the problem stated way recip is of radionuclide palladium-103 without media including the irradiation target from metallic rhodium on the accelerator, the electrochemical dissolution of the irradiated target in dilute hydrochloric acid and the selection of radionuclide palladium-103 from the resulting solution, characterized in that the selection of a radionuclide palladium-103 from the obtained solution is performed by sorption on strong-base anion exchange resin followed by elution of palladium-103 solution of ammonia, and prior to the sorption of sodium palladium-103 in dilute hydrochloric acid is added oxidant. In the particular case of the complete method sorption carried out on strong-base anion exchange resin Dowex H in Cl^--form. In each solution when conducting ion-exchange allocation radionuclide palladium-103 add an oxidizer, which can be used, for example, potassium bromate.

Suitable after carrying out sorption to conduct additional cleanup of radionuclide palladium-103 with its extraction into chloroform from the solution, which is obtained by evaporation of the eluate, followed by dissolving the residue containing palladium-103, hydrochloric acid, and prior to the extraction to the solution containing palladium-103, add alcohol solution of dimethylglyoxime.

The technical result of the proposed solutions is to provide high output and high quality of the product by reducing the number of organic substances, used in the allocation process of the radionuclide palladium-103, reducing the time of contact of organic substances with radioactive substances and, consequently, reducing the likelihood of formation of recalcitrant organic compounds and the reduction of losses of palladium-103 for account recovery.

The inventive method is as follows.

The irradiated target from metallic rhodium (weight of rhodium in the target is ˜ 2.4 to 6.0 g) is dissolved electrochemically in 6 M hydrochloric acid using alternating current. Department of palladium-103 from the main quantities of rhodium carried out by sorption, skipping the initial solution through the ion exchange column with a strong-base anion exchange resin such as Dowex H in Cl^--form. Prior to the sorption to the original solution is added an oxidizing agent (for example, potassium bromate), designed to interfere with the recovery of palladium sorbent. This palladium-103 is firmly held by the sorbent in the form of a chloride complex, and rhodium enters the eluate in the implementation of the elution. Removal of various impurities, including iron, copper, and radionuclides cobalt-56 and zinc-65, the column is washed first with 6 M hydrochloric acid and then with water, in which pre-add the same oxidant. Palladium-103 elute diluted rest the rum ammonia, containing the oxidant. The resulting eluate is present a small amount of rhodium (˜20-40 mg). To remove the solution evaporated to moist salts, then the residue is dissolved in dilute hydrochloric acid, followed by an additional extraction cleaning palladium-103. Sorption separation of palladium-103 from the main quantity of rhodium can significantly reduce the amount of each organic reagent used in the extraction purification of the product, namely: in the solution used for extraction, add 5 ml of 1-St % (wt.) alcohol solution of complexing agents (˜40 mg dimethylglyoxime) and extracted with palladium 40-50 ml of chloroform. The chloroform is removed by evaporation, and other organic impurities - processing of the Royal vodka. The final product is produced or in the form of a solution in 6 M hydrochloric acid, or ammonium buffer solution.

Thus, in the processing target, the amount of organic substances is substantially reduced compared to known methods: chloroform in ˜20-25 times, dimethylglyoxime - ˜12.5 to 15 times. Accordingly decreases and the time required for evaporation of the chloroform and oxidative decomposition of dimethylglyoxime, which reduces the time of exposure of radiation on organic substances and thereby decreases the probability of formation of recalcitrant organic compounds.

The proposed solution is illustrated by the following examples.

Example 1.

(Illustrates the shortcomings of sorption without added oxidant).

Irradiated on the cyclotron target with a mass of rhodium 2.8 g was dissolved in 6 M HCl under the action of alternating current. The resulting solution was evaporated to 50 ml, allowed to cool and put it through a column Packed with 10 ml of sorbent Dowex H (100-200 mesh), pre-saturated 6 M model HC1. After the sorption column was washed first with 50 ml of 6 M HCl, and then 50 ml of water. Palladium-103 was suirable 100 ml of 0.1 M aqueous solution of ammonia. Activity palladium-103 in the original solution was 7,13 Ki separated from the solution - a 3.87 Ki palladium-103, i.e. ˜54%.

Example 2.

The target is to obtain a palladium-103 was a copper block (substrate), the surface of which is welded to the metal plate rhodium weight 2,48, the Target was irradiated on the accelerator of protons with energy ˜and 13.5 MeV. Activity palladium-103 in the target at the end of irradiation was 38,80 Key. Rhodium plate separated from the copper substrate by dissolving the latter in concentrated nitric acid. Metal rhodium dissolved in 6 M HCl under the action of alternating current. The resulting solution was evaporated to 50 ml, allowed to cool and added 5 ml saturated at room temperature solution of potassium bromate (KBrO₃). The solution was mixed and put it across the column, filled with 10 ml of sorbent Dowex H (100-200 mesh), pre-saturated 6 M HCl. The column was washed with a mixture consisting of 45 ml of 6 M HCl and 5 ml of a saturated solution of KBrO₃.

Then the column was washed with a mixture consisting of 45 ml of water and 5 ml of a saturated solution of KBrO₃. Palladium-103 was suirable mixture solutions containing 90 ml of 0.1 M aqueous ammonia solution and 10 ml of a saturated solution of KBrO₃. The eluate palladium-103 was evaporated to moist salts, the residue was dissolved in 50 ml of 0.25 M HCl and added 5 ml of 1% (wt.) an alcohol solution of dimethylglyoxime. The complex of palladium-103 with dimethylglyoxime was extracted with 50 ml of chloroform. Chloroform containing palladium-103, washed with 30 ml of 0.25 M HCl solution, and then evaporated to dryness. The residue was treated with Imperial vodka for the decomposition of organic substances. After evaporation the residue was dissolved in 10 ml of ammonia buffer solution. In the result of the reprocessing of irradiated rhodium target was allocated 36,88 Ki activity recalculated at the end of irradiation)that amounted to ˜ 95% of the original quantity of the radionuclide. The specific activity of the product amounted to 57.0 CI/mg Pd, rhodium content was 13.8 mg/ml

The proposed method for radionuclide palladium-103 without media allows to obtain a product of high quality by reducing the amount of organic reagents used in the process ejecta is palladium-103, and reduce the time of contact of organic chemicals with radioactive substances. The method is characterized by stability and high output radionuclide palladium-103.

1. A method of producing a radionuclide palladium-103 without the media, including the irradiation of a target of metallic rhodium on the accelerator, the electrochemical dissolution of the irradiated target in dilute hydrochloric acid and the selection of radionuclide palladium-103 from the resulting solution, characterized in that the selection of a radionuclide palladium-103 from the obtained solution is performed by sorption on strong-base anion exchange resin followed by elution of palladium-103 solution of ammonia, and prior to the sorption of sodium palladium-103 in dilute hydrochloric acid is added oxidant.

2. The method according to claim 1, characterized in that the sorption is carried out on strong-base anion exchange resin Dowex 1X8 in Cl^-form.

3. The method according to claim 1 or 2, characterized in that the solutions for washing the column and elution of palladium-103 add the oxidizing agent.

4. The method according to claim 3, characterized in that as the oxidant use potassium bromate.

5. The method according to claim 3, characterized in that after the sorption conduct additional cleanup of radionuclide palladium-103 with its extraction into chloroform from the solution, which is obtained by evaporation of the eluate, followed by dissolving the residue content is the future of palladium-103, in hydrochloric acid.

6. The method according to claim 4, characterized in that after the sorption conduct additional cleanup of radionuclide palladium-103 with its extraction into chloroform from the solution, which is obtained by evaporation of the eluate, followed by dissolving the residue containing palladium-103, in dilute hydrochloric acid.

7. The method according to claim 5 or 6, characterized in that prior to the extraction to the solution containing palladium-103, add alcohol solution of dimethylglyoxime.