CN114956215A - Perchloric acid system containing pentavalent neptunium ions and preparation method thereof - Google Patents
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Abstract
The invention provides a perchloric acid system containing pentavalent neptunium ions and a preparation method thereof. The hexavalent neptunium ions are reduced by adopting an organic solvent pyridine instead of an inorganic salt as a reducing agent, and after removing acetonitrile and pyridine in a reaction system, pentavalent neptunium solid can be directly obtained.
Description
Technical Field
The invention relates to the technical field of preparation of pentavalent neptunium, in particular to a perchloric acid system containing pentavalent neptunium ions and a preparation method thereof.
Background
Neptunium (Np) typically exists in aqueous solution in three valence states, Np (iv), Np (v), Np (vi), with Np (v) being the most stable and common valence state. By researching the coordination behavior of Np (V) and inorganic anions or organic ligands, information such as coordination constants, thermodynamic parameters and the like can be obtained, and the method is favorable for understanding the species distribution and the migration behavior of Np (V) in an aqueous solution. Because of the absence of coordination between Np ions and perchlorate, solutions of Np-containing perchloric acid are usually obtained, wherein the preparation of the single valence Np (v) ions of the perchloric acid system is the first technical difficulty.
The preparation of solutions of Np (v) is typically a two-step process, where Np is oxidized to Np (vi) and then reduced to Np (v) using a reducing agent, commonly used as perchloric acid and sodium nitrite, respectively. Although the solution of np (v) can be prepared with high purity, the operation is cumbersome and radioactive waste liquid is generated.
Disclosure of Invention
Based on this, there is a need for a perchloric acid system containing pentavalent neptunium ions, which is simple to operate, does not generate radioactive waste liquid, and has high purity, and a preparation method thereof.
One embodiment provides a method for preparing a perchloric acid system containing pentavalent neptunium ions, comprising:
pyridine is used as a reducing agent, hexavalent neptunium ions are reduced to pentavalent neptunium ions in acetonitrile, after the acetonitrile and the pyridine in a reaction system are removed, perchloric acid solution is added, and a perchloric acid system containing the pentavalent neptunium ions is prepared.
In some embodiments, the method specifically comprises the following steps:
removing the solvent from the solution containing the hexavalent neptunium ions to produce a first solid;
dissolving the first solid with the acetonitrile to prepare a first solution;
adding the pyridine into the first solution to prepare the reaction system;
removing acetonitrile and pyridine in the reaction system to prepare a second solid;
and dissolving the second solid in the perchloric acid solution to obtain a perchloric acid system containing pentavalent neptunium ions.
In some embodiments, the mass ratio of the neptunium element contained in the first solution to the pyridine is 1 (400-1300).
In some embodiments, the solution containing the hexavalent neptunium ions comprises one or more of a nitric acid solution containing the hexavalent neptunium ions and a perchloric acid solution containing the hexavalent neptunium ions.
In some embodiments, the molar concentration of the perchloric acid solution is 0.1 to 2.0 mol/L.
In some embodiments, the method further comprises determining whether the hexavalent neptunium ions contained in the first solution are completely reduced;
alternatively, when the reaction system is a bright green clear solution containing no precipitate, it is determined that the hexavalent neptunium ions contained in the first solution are completely reduced.
In some embodiments, the solvent in the solution containing the hexavalent neptunium ions is removed by heating at 90 to 140 ℃.
In some embodiments, the acetonitrile and pyridine are removed from the reaction system by draining the solvent while stirring.
In some of these embodiments, the stirring speed is 750-1200 r/min.
One embodiment provides a perchloric acid system containing pentavalent neptunium ions, which is prepared by the preparation method of the perchloric acid system containing the pentavalent neptunium ions.
The perchloric acid system containing the pentavalent neptunium ions and the preparation method thereof adopt pyridine as a reducing agent, hexavalent neptunium ions are reduced to the pentavalent neptunium ions in acetonitrile, and then after the acetonitrile and the pyridine in the reaction system are removed, a perchloric acid solution is added to prepare the perchloric acid system containing the pentavalent neptunium ions; the organic solvent pyridine is adopted to replace inorganic salt as a reducing agent to reduce hexavalent neptunium ions, and after acetonitrile and pyridine in a reaction system are removed, pentavalent neptunium solid can be directly obtained.
Detailed Description
In order that the invention may be more fully understood, reference will now be made to the accompanying examples. The following provides a preferred embodiment of the invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
It is understood that the technical features described in the open-ended form herein include closed technical solutions including the listed features, and also include open technical solutions including the listed features.
As used herein, "one or more" refers to any one or a combination of any two or more of the listed items.
Herein, reference to numerical intervals is deemed continuous within the numerical intervals, unless otherwise stated, and includes the minimum and maximum values of the range, as well as each and every value between such minimum and maximum values. Further, when a range refers to an integer, each integer between the minimum and maximum values of the range is included. Further, when multiple range-describing features or characteristics are provided, the ranges may be combined. In other words, unless otherwise indicated, all ranges disclosed herein are to be understood to encompass any and all subranges subsumed therein.
In this context, referring to units of the data range, if only with units after the right end point, the units representing the left end point and the right end point are the same. For example, 0.1 to 2.0mol/L indicates that the units of the left end point "0.1" and the right end point "2.0" are mol/L.
The temperature parameter herein is not particularly limited, and is allowed to be either constant temperature treatment or treatment within a certain temperature range. The constant temperature process allows the temperature to fluctuate within the accuracy of the instrument control.
Neptunium (Np) typically exists in aqueous solution in three valence states, Np (iv), Np (v), Np (vi), with Np (v) being the most stable and common valence state. Through researching the coordination behavior of Np (V) and inorganic anions or organic ligands, information such as coordination constants, thermodynamic parameters and the like can be obtained, and the method is favorable for understanding the species distribution and the migration behavior of Np (V) in an aqueous solution. Because of the absence of coordination between Np ions and perchlorate, solutions of Np-containing perchloric acid are usually obtained, wherein the preparation of the single valence Np (v) ions of the perchloric acid system is the first technical difficulty.
The preparation of solutions of Np (v) is typically a two-step process, where Np is oxidized to Np (vi) and then reduced to Np (v) using a reducing agent, commonly used as perchloric acid and sodium nitrite, respectively. The specific method comprises the following steps: mixing solid NpO 2 Dissolving in concentrated perchloric acid, adding several drops of concentrated hydrochloric acid, heating to remove excessive perchloric acid and small amount of hydrochloric acid, and oxidizing Np to Np (VI) to become pink. A small amount of sodium nitrite is added to the pink solution of Np (VI), which turns green and is reduced to Np (V). Subsequent addition of 1mol/L sodium hydroxide to the solution produced NpO 2 OH precipitation, centrifugation and repeated washing of the precipitate with deionized water three times to ensure removal of excess sodium hydroxide, and finally dissolution of the precipitate with 1mol/L perchloric acid to give a perchloric acid solution containing Np (V). Although the above method can obtain a high-purity Np (v) solution, the operation is complicated, radioactive waste liquid is generated, and Np loss is inevitably caused in the precipitation process.
In order to solve the above problems, an embodiment provides a method for preparing a perchloric acid system containing pentavalent neptunium ions, which may include: pyridine is used as a reducing agent, hexavalent neptunium ions are reduced to pentavalent neptunium ions in acetonitrile, and after the acetonitrile and the pyridine in a reaction system are removed, perchloric acid solution is added to prepare a perchloric acid system containing the pentavalent neptunium ions.
The preparation method adopts an organic solvent pyridine to replace inorganic salt as a reducing agent to reduce hexavalent neptunium ions, and after removing acetonitrile and pyridine in a reaction system, pentavalent neptunium solid can be directly obtained.
In some embodiments, the method specifically includes the following steps:
removing the solvent from the solution containing the hexavalent neptunium ions to produce a first solid;
dissolving the first solid with the acetonitrile to prepare a first solution;
adding the pyridine into the first solution to prepare the reaction system;
removing acetonitrile and pyridine in the reaction system to prepare a second solid;
and dissolving the second solid in the perchloric acid solution to prepare a perchloric acid system containing pentavalent neptunium ions.
It will be understood that the first solid is a solid containing hexavalent neptunium; the first solution is a solution containing hexavalent neptunium ions, the reaction system is a solution containing pentavalent neptunium ions, and the second solid is a solid containing pentavalent neptunium.
The amount of acetonitrile to be added is preferably such that the first solid can be completely dissolved, and the amount of the perchloric acid solution to be added is preferably such that the second solid can be completely dissolved.
In some embodiments, the mass ratio of the neptunium element contained in the first solution to the pyridine may be 1 (400-1300); for example, the ratio may be 1:400, 1:500, 1:600, 1:700, 1:800, 1:900, 1:1000, 1:1100, 1:1200, 1:1300, or 1:1400, without being limited thereto. When the mass ratio of the neptunium element to the pyridine in the first solution is 1 (400-1300), the hexavalent neptunium ions in the first solution can be fully reduced.
In some embodiments, the solution containing hexavalent neptunium ions may include one or more of a nitric acid solution containing the hexavalent neptunium ions and a perchloric acid solution containing the hexavalent neptunium ions.
In some embodiments, the molar concentration of the perchloric acid solution may be 0.1 to 2.0 mol/L; for example, it may be 0.1mol/L, 0.2mol/L, 0.3mol/L, 0.4mol/L, 0.5mol/L, 0.6mol/L, 0.7mol/L, 0.8mol/L, 0.9mol/L, 1.0mol/L, 1.1mol/L, 1.2mol/L, 1.3mol/L, 1.4mol/L, 1.5mol/L, 1.6mol/L, 1.7mol/L, 1.8mol/L, 1.9mol/L or 2.0mol/L, etc., and the examples are not limited. When the molar concentration of the perchloric acid solution is 0.1-2.0 mol/L, pentavalent neptunium ions can stably exist in the perchloric acid solution for a long time; if the molar concentration of the perchloric acid solution is too high, the pentavalent neptunium ions may undergo a disproportionation reaction.
In some embodiments, it may further comprise determining whether the hexavalent neptunium ions contained in the first solution are completely reduced.
In some of these examples, it is possible to determine that the hexavalent neptunium ions contained in the first solution are completely reduced when the reaction system is a bright green clear solution containing no precipitate.
In some embodiments, the solvent in the solution containing the hexavalent neptunium ions can be removed by heating at 90-140 ℃; for example, the temperature may be 90 ℃, 95 ℃, 100 ℃, 105 ℃, 110 ℃, 115 ℃, 120 ℃, 125 ℃, 130 ℃, 135 ℃ or 140 ℃ and the like, and the temperature is not particularly limited.
In some embodiments, acetonitrile and pyridine may be removed from the reaction system by pumping the solvent while stirring. With the reduction of acetonitrile, the amount of the pentavalent neptunium which can be dissolved in the acetonitrile is reduced, the redundant pentavalent neptunium can be precipitated in a solid form, and the pentavalent neptunium solid can be obtained after the acetonitrile and the pyridine are pumped to dryness.
In some embodiments, the stirring speed can be 750-; for example, the ratio may be 750r/min, 800r/min, 850r/min, 900r/min, 950r/min, 1000r/min, 1050r/min, 1100r/min, 1150r/min or 1200r/min, etc., without limitation.
One embodiment provides a perchloric acid system containing pentavalent neptunium ions, which is prepared by the above method for preparing a perchloric acid system containing pentavalent neptunium ions.
The perchloric acid system containing pentavalent neptunium ions and the process for its preparation according to the invention are described in detail below with reference to the specific examples.
It should be noted that the second solution in the following examples is a reaction system obtained after the pyridine reduces the hexavalent neptunium ions in the first solution.
Example 1
A10 mL glass bottle was filled with 1mL perchloric acid solution containing 10mmol/L Np (VI). The glass bottle is placed on a heater and heated to be dried at 100 ℃ to obtain a first solid containing hexavalent Np.
And dissolving the first solid containing the hexavalent Np after evaporation by using 1mL of acetonitrile solution to obtain a first solution containing hexavalent Np ions and having a light pink color.
Then, 2mL of pyridine solution was added to the first solution, the first solution immediately became dark brown, and after standing for 3 days, the solution was observed to be a bright green clear solution, that is, a second solution.
The second solution was transferred to a 50mL round bottom flask, magnetons were added and the solvent (acetonitrile/pyridine) was pumped off at a stirring speed of 1000r/min to give a second solid containing pentavalent Np.
Dissolving the second solid by adopting 2mL of 1.0mol/L perchloric acid solution to obtain perchloric acid solution containing single valence state Np (V) ions.
And (3) putting 10 mu L of the perchloric acid solution containing Np (V) ions into a liquid scintillation bottle, adding 10mL of scintillation liquid, screwing a bottle cover, and then shaking horizontally for 50-100 min to fully mix the perchloric acid solution and the scintillation liquid. And then putting the liquid scintillation bottle into a liquid scintillation counter for liquid scintillation measurement, and recording alpha-channel counting, wherein the measurement time is 5 min. The final measured alpha count was 19055.652 and the calculated concentration of the perchloric acid solution was 5.1 mmol/L.
Taking 50 mu L of the perchloric acid solution containing Np (V) ions, adding 750 mu L of 1.0mol/L perchloric acid solution into a cuvette, measuring the absorption spectrum of the perchloric acid solution containing Np (V) ions in the cuvette by taking 1.0mol/L blank perchloric acid solution as a reference, wherein the spectrum range is 355 nm-1400 nm, and determining that only Np (V) ions exist in the solution and no Np ions in other valence states exist. The absorbance of the absorption peak at 980nm of Np (V) was 0.123, and the concentration of Np (V) ions was 5.0mmol/L as calculated from the absorbance of the absorption peak at 980nm of Np (V), and the results of the spectroscopic measurement were consistent with those of the liquid flash measurement.
The calculated amount of Np substance before and after reduction is 0.01mmol, and no loss of Np occurs.
Example 2
A10 mL glass bottle was filled with 5mL of a perchloric acid solution containing 20mmol/L of Np (VI). The glass bottle was placed on a heater and heated at 140 ℃ to dryness to obtain a first solid containing hexavalent Np.
And dissolving the first solid containing the hexavalent Np after evaporation by using 3mL of acetonitrile solution to obtain a first solution containing hexavalent Np ions and having a light pink color.
Then 3mL of pyridine solution was added to the first solution, the first solution immediately became dark brown, after standing for 3 days, dark green insoluble substances were observed at the bottom of the bottle, and the upper layer was a bright green clear solution, i.e., the second solution, and the precipitate in the glass bottle was filtered off.
The second solution was transferred to a 50mL round bottom flask, magnetons were added and the solvent (acetonitrile/pyridine) was pumped off at a stirring speed of 1000r/min to give a second solid containing pentavalent Np.
And dissolving the second solid by using 6mL of 1.0mol/L perchloric acid solution to obtain perchloric acid solution containing single valence Np (V) ions.
And (3) putting 10 mu L of the perchloric acid solution containing Np (V) ions into a liquid scintillation bottle, adding 10mL of scintillation liquid, screwing a bottle cover, and then shaking horizontally for 50-100 min to fully mix the perchloric acid solution and the scintillation liquid. And then putting the liquid scintillation bottle into a liquid scintillation counter for liquid scintillation measurement, and recording alpha-channel counting, wherein the measurement time is 5 min. The final measured alpha count was 39099.403 and the calculated concentration of the perchloric acid solution was 10.5 mmol/L.
Taking 50 mu L of the perchloric acid solution containing Np (V) ions, adding 750 mu L of 1.0mol/L perchloric acid solution into a cuvette, measuring the absorption spectrum of the perchloric acid solution containing Np (V) ions in the cuvette by taking 1.0mol/L blank perchloric acid solution as a reference, wherein the spectrum range is 355 nm-1400 nm, and determining that only Np (V) ions exist in the solution and no Np ions in other valence states exist. The absorbance of the absorption peak at 980nm of Np (V) was 0.260, and the concentration of Np (V) ions was calculated to be 10.5mmol/L from the absorbance of the absorption peak at 980nm of Np (V), and the results of the spectroscopic measurement were consistent with those of the liquid flash measurement.
A dark green insoluble solid was explored by taking a portion of the solid in a 25mL round bottom flask and adding 2mL of acetonitrile solution, which did not dissolve significantly. The acetonitrile solution was drained and 2mL of 1.0mol/L perchloric acid solution was added, and the solid was completely dissolved, resulting in a yellow-green solution.
mu.L of the dissolved solution was subjected to liquid flash measurement, and the alpha count was 34300.122, indicating that the solid contained Np, and the concentration of the Np solution was calculated to be 18.5 mmol/L.
And (3) adding 750 mu L of 1.0mol/L perchloric acid solution into a cuvette after 50 mu L of the dissolved solution is taken, measuring the absorption spectrum of the Np (V) solution in the cuvette by taking 1.0mol/L blank perchloric acid solution as a reference, wherein the spectral range is 355 nm-1400 nm, and characteristic absorption peaks appear at 980nm and 1223nm on the spectrum, which indicates that Np (V) and Np (VI) exist simultaneously, and the concentration ratio of Np (V) to Np (VI) is 3: 2. The above results show that Np (VI) is not completely reduced and insoluble matter is generated when the amount of pyridine added is too small.
And adding 3-6 mL of pyridine into the residual solid, standing for 2-5 days, and allowing insoluble substances to disappear to obtain a bright green clear solution. Thus, whether the precipitation is generated or not is related to whether the reduction of Np (VI) is complete or not.
The total amount of Np in the solution after reduction and in the precipitate was calculated to be 0.1mmol, consistent with the amount of Np prior to reduction, with no loss of Np.
Example 3
A10 mL glass bottle was filled with 1mL perchloric acid solution containing 10mmol/L Np (VI). The glass bottle is placed on a heater, heated and evaporated to dryness at 90 ℃ to obtain a first solid containing hexavalent Np.
And dissolving the first solid containing the hexavalent Np after evaporation by using 3mL of acetonitrile solution to obtain a first solution containing hexavalent Np ions and having a light pink color.
Then, 3mL of pyridine solution was added to the first solution, the first solution immediately became dark brown, and after standing for 2 days, the solution was observed to be a bright green clear solution, that is, a second solution.
The second solution was transferred to a 50mL round bottom flask, magnetons were added, and the solvent (acetonitrile/pyridine) was pumped off at a stirring speed of 750r/min to give a second solid containing pentavalent Np.
And dissolving the second solid by using 5mL of 0.1mol/L perchloric acid solution to obtain perchloric acid solution containing single valence Np (V) ions.
And (3) putting 10 mu L of the perchloric acid solution containing Np (V) ions into a liquid scintillation bottle, adding 10mL of scintillation liquid, screwing a bottle cover, and then shaking horizontally for 50-100 min to fully mix the perchloric acid solution and the scintillation liquid. And then putting the liquid scintillation bottle into a liquid scintillation counter for liquid scintillation measurement, and recording alpha-channel counting, wherein the measurement time is 5 min. The final measured alpha count was 7600.260 and the calculated concentration of the perchloric acid solution was 2.0 mmol/L.
Taking 100 mu L of the perchloric acid solution containing Np (V) ions, adding 700 mu L of 1.0mol/L perchloric acid solution into a cuvette, measuring the absorption spectrum of the perchloric acid solution containing Np (V) ions in the cuvette by taking 1.0mol/L blank perchloric acid solution as a reference, wherein the spectrum range is 355 nm-1400 nm, and determining that only Np (V) ions exist in the solution and no Np ions in other valence states exist. The absorbance of the absorption peak at 980nm of Np (V) was 0.098, and the concentration of Np (V) ions was 2.0mmol/L as calculated from the absorbance of the absorption peak at 980nm of Np (V), and the results of the spectroscopic measurement were consistent with those of the liquid flash measurement.
The calculated amount of Np substance before and after reduction is 0.01mmol, and no loss of Np occurs.
Example 4
A10 mL glass bottle was filled with 1mL perchloric acid solution containing 10mmol/L Np (VI). The glass bottle was placed on a heater and heated at 140 ℃ to dryness to obtain a first solid containing hexavalent Np.
And dissolving the first solid containing the hexavalent Np after evaporation by using 2mL of acetonitrile solution to obtain a first solution containing hexavalent Np ions and having a light pink color.
Then, 1mL of pyridine solution was added to the first solution, the first solution immediately became dark brown, and after standing for 5 days, the solution was observed to be a bright green clear solution, that is, a second solution.
The second solution was transferred to a 50mL round bottom flask, magnetons were added, and the solvent (acetonitrile/pyridine) was drained under 1200r/min stirring to give a second solid containing pentavalent Np.
4mL of 2.0mol/L perchloric acid solution is adopted to dissolve the second solid, and the perchloric acid solution containing single valence Np (V) ions can be obtained.
And (3) putting 10 mu L of the perchloric acid solution containing Np (V) ions into a liquid scintillation bottle, adding 10mL of scintillation liquid, screwing a bottle cover, and then shaking horizontally for 50-100 min to fully mix the perchloric acid solution and the scintillation liquid. And then putting the liquid scintillation bottle into a liquid scintillation counter for liquid scintillation measurement, and recording alpha channel counting, wherein the measurement time is 5 min. The final measured alpha count was 9550.826 and the calculated concentration of the perchloric acid solution was 2.6 mmol/L.
Taking 100 mu L of the perchloric acid solution containing Np (V) ions, adding 700 mu L of 1.0mol/L perchloric acid solution into a cuvette, measuring the absorption spectrum of the perchloric acid solution containing Np (V) ions in the cuvette by taking 1.0mol/L blank perchloric acid solution as a reference, wherein the spectrum range is 355 nm-1400 nm, and determining that only Np (V) ions exist in the solution and no Np ions in other valence states exist. The absorbance of an absorption peak at 980nm of Np (V) was 0.125, the concentration of Np (V) ions was calculated as 2.5mmol/L from the absorbance of an absorption peak at 980nm of Np (V), and the results of the spectroscopic measurement were consistent with those of the liquid flash measurement.
The calculated amount of Np substance before and after reduction is 0.01mmol, and no loss of Np occurs.
Comparative example 1
Comparative example 1 and examples 1 to 4 differ in that: inorganic sodium nitrite is used as a reducing agent.
Taking a 10mL glass bottle, and adding NpO with the neptunium content of about 90mg 2 The solid is dissolved in 5mL of concentrated nitric acid, and 4-5 drops of concentrated perchloric acid are added simultaneously. The glass bottle was placed on a heater and heated to dryness, and then dissolved with 5ml of 1.0mol/L nitric acid, and the solution was pink, which confirmed that Np was Np (VI). By adding 1mL of 2.0mol/L sodium nitrite to the solution, a green color of the solution was observed, indicating that Np (VI) was reduced to Np (V). The Np solution is transferred to a 25mL centrifuge tube, 4.0mol/L sodium hydroxide is added dropwise to the Np solution, a greenish precipitate is generated in the solution, the solution is gradually added dropwise until the precipitate does not increase any more, and 6mL of sodium hydroxide solution is added in total. And placing the centrifugal tube in a centrifugal machine for centrifuging for 2-3 min at the rotating speed of 3000-3200 rpm. After centrifugation, a light-colored solid is arranged at the bottom of the tube, and the supernatant is colorless and transparent; transferring the supernatant to a radioactive waste liquid bottle, and transferring the supernatant to the greatest extent. Then 2mL of pure water is added for washing, the mixture is centrifuged for 3min to carry out phase separation, the supernatant is also transferred into a radioactive waste liquid bottle, and the washing operation is repeated three times. The final solid was dissolved in 5mL of 1.0mol/L perchloric acid solution, which was green.
5 μ L of Np solution was taken for liquid flash measurement and the final Np content was calculated to be about 85 mg. And then, carrying out absorption spectrum measurement on the Np solution, wherein the spectrum range is 960-1010 nm, the Np (V) is confirmed, but the baseline in the measurement process is obviously shifted, other impurities possibly exist in the solution, and the purity of the Np (V) is not good enough.
Comparing examples 1-4 with comparative example 1, the preparation method in comparative example 1 mainly comprises the following steps: heating and evaporating the nitric acid solution containing Np to dryness to obtain Np (VI), adding sodium nitrite to reduce Np (VI) to Np (V), and adding sodium hydroxide to obtain NpO 2 OH precipitation, centrifugation, washing of the precipitate with pure water and further centrifugation, dissolving the Np (V) solid in perchloric acid solution.
The production method in comparative example 1 has the following problems compared with the production method of the present invention: the steps are complicated, the Np has small loss, radioactive waste liquid is generated, and the final Np solution has poor purity. The perchloric acid system containing pentavalent neptunium ions and the preparation method thereof provided by the invention have the advantages that organic solvent pyridine is adopted to replace inorganic salt as a reducing agent to reduce the hexavalent neptunium, acetonitrile and pyridine in a reaction system are removed, and then pentavalent neptunium solid can be directly obtained.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (10)
1. A method for preparing a perchloric acid system containing pentavalent neptunium ions, comprising:
pyridine is used as a reducing agent, hexavalent neptunium ions are reduced to pentavalent neptunium ions in acetonitrile, and after the acetonitrile and the pyridine in a reaction system are removed, perchloric acid solution is added to prepare a perchloric acid system containing the pentavalent neptunium ions.
2. The method according to claim 1, characterized in that it comprises the following steps:
removing the solvent from the solution containing the hexavalent neptunium ions to produce a first solid;
dissolving the first solid with the acetonitrile to prepare a first solution;
adding the pyridine into the first solution to prepare the reaction system;
removing acetonitrile and pyridine in the reaction system to prepare a second solid;
and dissolving the second solid in the perchloric acid solution to prepare a perchloric acid system containing pentavalent neptunium ions.
3. The method for preparing the perchloric acid system containing the pentavalent neptunium ions according to claim 2, wherein the mass ratio of the neptunium element contained in the first solution to the pyridine is 1 (400-1300).
4. The method of claim 2, wherein the solution containing the hexavalent neptunium ions comprises one or more of a nitric acid solution containing the hexavalent neptunium ions and a perchloric acid solution containing the hexavalent neptunium ions.
5. The method according to claim 2, wherein the molar concentration of the perchloric acid solution is 0.1 to 2.0 mol/L.
6. The method of claim 2, further comprising determining whether the hexavalent neptunium ions contained in said first solution are completely reduced;
alternatively, when the reaction system is a bright green clear solution containing no precipitate, it is determined that the hexavalent neptunium ions contained in the first solution are completely reduced.
7. The method according to claim 2, characterized in that the solvent in the solution containing the neptunium pentavalent ions is removed by heating at 90 to 140 ℃.
8. The method according to claim 2 to 7, wherein acetonitrile and pyridine in the reaction system are removed by stirring and solvent evacuation.
9. The method according to claim 8, wherein the stirring speed is 750-.
10. A perchloric acid system containing pentavalent neptunium ions, characterized in that it is produced by the method of any one of claims 1 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN202210627863.6A CN114956215B (en) | 2022-06-06 | 2022-06-06 | Perchloric acid system containing pentavalent neptunium ions and preparation method thereof |
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| CN116040583A (en) * | 2022-10-24 | 2023-05-02 | 清华大学 | Perchloric acid system containing tetravalent neptunium ions and preparation method thereof |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4112044A (en) * | 1975-09-06 | 1978-09-05 | Asahi Kasei Kogyo Kabushiki Kaisha | Chromatographic separation of uranium isotopes |
| JPS6130799A (en) * | 1984-07-24 | 1986-02-13 | 日本原子力研究所 | Method of separating neptunium |
| JPH06194496A (en) * | 1992-12-25 | 1994-07-15 | Hitachi Ltd | Reduction method of neptunium in fuel reprocessing solution |
| CA2221703A1 (en) * | 1995-05-30 | 1996-12-05 | The Regents Of The University Of California | Process for recovery of metal ions |
| US20070221510A1 (en) * | 2005-11-15 | 2007-09-27 | Russell Dale D | Field portable electrochemical sensor for uranium and other actinides |
| US20090184051A1 (en) * | 2006-04-19 | 2009-07-23 | Xavier Heres | Grouped separation of actinides from a highly acidic aqueous phase |
| CN109206554A (en) * | 2017-07-03 | 2019-01-15 | 华中科技大学 | A kind of ion imprinted polymer material of photo-reduction Cr VI and its preparation and application |
| US20220072509A1 (en) * | 2020-09-08 | 2022-03-10 | The Regents Of The University Of California | Method for liquid-to-solid phase separation of uranium and uranyl contaminant from various solutions |
| CN114195137A (en) * | 2022-01-14 | 2022-03-18 | 曲靖华金雨林科技有限责任公司 | Method for preparing graphene |
-
2022
- 2022-06-06 CN CN202210627863.6A patent/CN114956215B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4112044A (en) * | 1975-09-06 | 1978-09-05 | Asahi Kasei Kogyo Kabushiki Kaisha | Chromatographic separation of uranium isotopes |
| JPS6130799A (en) * | 1984-07-24 | 1986-02-13 | 日本原子力研究所 | Method of separating neptunium |
| JPH06194496A (en) * | 1992-12-25 | 1994-07-15 | Hitachi Ltd | Reduction method of neptunium in fuel reprocessing solution |
| CA2221703A1 (en) * | 1995-05-30 | 1996-12-05 | The Regents Of The University Of California | Process for recovery of metal ions |
| US20070221510A1 (en) * | 2005-11-15 | 2007-09-27 | Russell Dale D | Field portable electrochemical sensor for uranium and other actinides |
| US20090184051A1 (en) * | 2006-04-19 | 2009-07-23 | Xavier Heres | Grouped separation of actinides from a highly acidic aqueous phase |
| CN109206554A (en) * | 2017-07-03 | 2019-01-15 | 华中科技大学 | A kind of ion imprinted polymer material of photo-reduction Cr VI and its preparation and application |
| US20220072509A1 (en) * | 2020-09-08 | 2022-03-10 | The Regents Of The University Of California | Method for liquid-to-solid phase separation of uranium and uranyl contaminant from various solutions |
| CN114195137A (en) * | 2022-01-14 | 2022-03-18 | 曲靖华金雨林科技有限责任公司 | Method for preparing graphene |
Non-Patent Citations (4)
| Title |
|---|
| V. S. KOLTUNOVS. ET AL.: "Kinetics and mechanism of Np and Pu reactions with organic derivatives of hydrazine", 《INORGANICA CHIMICA ACTA》 * |
| 尹东光等: "偏二甲基肼还原Np(Ⅵ)的动力学研究", 《核化学与放射化学》 * |
| 尹东光等: "铁离子和亚硝酸对偏二甲基肼还原六价镎的影响", 《核化学与放射化学》 * |
| 王妍等: "氨基羟基脲与Np(Ⅵ)的还原动力学", 《核化学与放射化学》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116040583A (en) * | 2022-10-24 | 2023-05-02 | 清华大学 | Perchloric acid system containing tetravalent neptunium ions and preparation method thereof |
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