An o-phenanthroline derivative extractant, its preparation method and application

Abstract

The application provides an o-phenanthroline derivative extractant as well as a preparation method and application thereof, relates to the technical field of nuclear fuel cycle and high-level liquid waste treatment. The o-phenanthroline derivative extractant provided by the application has a structure shown in formula I, and the o-phenanthroline derivative extractant provided by the application has strong extraction capacity for trivalent actinide elements, and can realize efficient removal of the trivalent actinide elements.

Description

Technical Field

[0001] This invention relates to the field of nuclear fuel cycle and high-level radioactive waste treatment technology, specifically to an o-phenanthroline-derived extractant, its preparation method, and its application. Background Technology

[0002] With the increasing consumption of fossil fuels, clean energy sources such as nuclear power are an inevitable choice for global energy development. Nuclear power, as a clean energy source, is an important component of my country's energy system. To date, my country has over 50 commercially operating nuclear power units with a total installed capacity exceeding 56 million kilowatts, ranking third globally. More than 20 nuclear power units are under construction, maintaining China's position as the world's largest nuclear power nation for over a decade.

[0003] Spent fuel generated during nuclear power plant operation can recover over 99.5% of its uranium and plutonium through the commercially available PUREX process. Other long-lived nuclides, fission products, and minor actinides end up in high-level radioactive waste. Minor actinides are one of the main sources of long-term radioactivity in high-level radioactive waste. Separating and transmutating them into short-lived or stable nuclides is crucial for reducing the long-term radioactive threat posed by nuclear waste.

[0004] Minor actinides constitute only about 0.1% of spent fuel. However, spent fuel contains a large amount of lanthanides, which are dozens of times more abundant than minor actinides. Since lanthanides and actinides have similar ionic radii and valence states, their chemical properties are very similar. Furthermore, some lanthanides are neutron poisons and can severely affect the transmutation of minor actinides. In addition, high-level radioactive waste liquids are highly acidic, radioactive, and have a complex composition. All these factors combined make the selective separation of minor actinides from high-level radioactive waste liquids extremely difficult. Summary of the Invention

[0005] The purpose of this invention is to provide an o-phenanthroline-derived extractant, its preparation method, and its application. The o-phenanthroline-derived extractant provided by this invention has a strong extraction ability for trivalent actinides and can achieve efficient removal of trivalent actinides.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0007] This invention provides an o-phenanthroline-derived extractant having the structure shown in Formula I:

[0008]

[0009] This invention provides a method for preparing the o-phenanthroline-derived extractant described in the above technical solution, comprising the following steps:

[0010] 2,9-Dimethyl-1,10-phenanthroline, 1,4-dioxane and an oxidant were mixed and oxidized to obtain 1,10-phenanthroline-2,9-dicarboxaldehyde.

[0011] The 1,10-phenanthroline-2,9-dicarboxaldehyde, acetonitrile, hydroxylamine hydrochloride and triethylamine were mixed and subjected to reflux reaction. After cooling, 1,8-diazabicycloundec-7-ene and p-toluenesulfonyl chloride were added to carry out the first substitution reaction to obtain 2,9-dicyano-1,10-phenanthroline.

[0012] The 2,9-dicyano-1,10-phenanthroline and hydrazine hydrate were mixed and subjected to a second substitution reaction to obtain 1,10-phenanthroline-2,9-diaminohydrazone;

[0013] The 1,10-phenanthroline-2,9-diaminohydrazone, 4-methylcamphorquinone, and toluene were mixed and subjected to a third substitution reaction to obtain an o-phenanthroline-derived extractant with the structure shown in Formula I.

[0014] Preferably, the oxidation reaction temperature is 90–140°C; the oxidation reaction time is 30 min–5 h.

[0015] Preferably, the temperature of the first substitution reaction is 90–140°C, and the time of the first substitution reaction is 20–30 h.

[0016] Preferably, the temperature of the second substitution reaction is room temperature; the time of the second substitution reaction is 20-30 hours.

[0017] Preferably, the temperature of the third substitution reaction is room temperature; the time of the third substitution reaction is 20-30 hours.

[0018] This invention provides the application of the o-phenanthroline-derived extractant described in the above-described technical solution or the o-phenanthroline-derived extractant prepared by the above-described technical solution in the separation of trivalent lanthanum and actinium.

[0019] Preferably, the application includes: mixing a diluent containing an extractant with an aqueous nitric acid solution containing trivalent lanthanum and actinium, and performing extraction separation; wherein the extractant is the o-phenanthroline-derived extractant described in the above technical solution or the o-phenanthroline-derived extractant prepared by the preparation method described in the above technical solution.

[0020] Preferably, the concentration of the extractant in the diluent is 1–50 mmol / L; and the concentration of nitric acid in the nitric acid aqueous solution containing trivalent lanthanum-actinium is 0.1–4 mol / L.

[0021] Preferably, the aqueous nitric acid solution containing trivalent lanthanum-actinium also includes a salting-out agent.

[0022] This invention provides an o-phenanthroline-derived extractant, which has a high pre-organized rigid structure, can shorten the extraction equilibrium time, and achieve rapid separation of trivalent lanthanum and actinium.

[0023] The extractant of this invention has the characteristics of simple synthesis, fast extraction kinetics (equilibrium in 5 minutes), strong extraction effect on trivalent actinides over a wide acidity range, and good separation effect of lanthanum and actinides (separation coefficient as high as 1000). It contains only four elements: C, H, O, and N. After use, it can be completely incinerated, avoiding the generation of secondary radioactive solid waste. It has important application prospects in the separation of trivalent lanthanum and actinides in the nuclear fuel cycle.

[0024] The o-phenanthroline-derived extractant provided by this invention has a strong extraction ability for trivalent actinides, and under preferred conditions can achieve efficient removal of trivalent actinides with a removal efficiency greater than 99%.

[0025] The o-phenanthroline-derived extractant provided by this invention exhibits rapid extraction kinetics for trivalent actinides, reaching equilibrium within 5 minutes. This can improve separation efficiency and reduce radiation damage to the extractant caused by prolonged contact. Attached Figure Description

[0026] Figure 1 The o-phenanthroline-derived extractant prepared in Example 1 1 1H NMR spectrum (solvent CDCl3, 400MHz, 25℃);

[0027] Figure 2 The o-phenanthroline-derived extractant prepared in Example 1 13 C10 NMR spectrum (solvent CDCl3, 100 MHz, 25 °C);

[0028] Figure 3 The mass spectrum of the o-phenanthroline-derived extractant prepared in Example 1;

[0029] Figure 4 The effect of nitric acid concentration on the separation of lanthanum actinide from the o-phenanthroline-derived extractant prepared in Example 1 during the extraction experiment;

[0030] Figure 5 The effect of time on the separation of lanthanum actinium from the o-phenanthroline-derived extractant prepared in Example 1 was investigated in the extraction experiment. Detailed Implementation

[0031] This invention provides an o-phenanthroline-derived extractant having the structure shown in Formula I:

[0032]

[0033] This invention provides a method for preparing the o-phenanthroline-derived extractant described in the above technical solution, comprising the following steps:

[0034] 2,9-Dimethyl-1,10-phenanthroline, 1,4-dioxane and an oxidant were mixed and oxidized to obtain 1,10-phenanthroline-2,9-dicarboxaldehyde.

[0035] The 1,10-phenanthroline-2,9-dicarboxaldehyde, acetonitrile, hydroxylamine hydrochloride and triethylamine were mixed and subjected to reflux reaction. After cooling, 1,8-diazabicycloundec-7-ene and p-toluenesulfonyl chloride were added to carry out the first substitution reaction to obtain 2,9-dicyano-1,10-phenanthroline.

[0036] The 2,9-dicyano-1,10-phenanthroline and hydrazine hydrate were mixed and subjected to a second substitution reaction to obtain 1,10-phenanthroline-2,9-diaminohydrazone;

[0037] The 1,10-phenanthroline-2,9-diaminohydrazone, 4-methylcamphorquinone, and toluene were mixed and subjected to a third substitution reaction to obtain an o-phenanthroline-derived extractant with the structure shown in Formula I.

[0038] This invention involves mixing 2,9-dimethyl-1,10-phenanthroline, 1,4-dioxane, and an oxidizing agent to undergo an oxidation reaction, yielding 1,10-phenanthroline-2,9-dicarboxaldehyde. In this invention, the oxidizing agent preferably comprises selenium dioxide. In this invention, the mixing is preferably carried out under stirring conditions. In this invention, the mixing preferably comprises: first dissolving 2,9-dimethyl-1,10-phenanthroline in 1,4-dioxane, and then adding the oxidizing agent.

[0039] In this invention, the molar ratio of the oxidant to 2,9-dimethyl-1,10-phenanthroline is preferably 1 to 5:1, more preferably 2 to 3:1; the mass ratio of 1,4-dioxane to 2,9-dimethyl-1,10-phenanthroline is preferably 10 to 20:1, more preferably 15 to 18:1.

[0040] In this invention, the temperature of the oxidation reaction is preferably 90–140°C, more preferably 110–120°C; the time of the oxidation reaction is preferably 30 min–5 h, more preferably 40 min–3 h. In this invention, the oxidation reaction is preferably carried out in an air atmosphere.

[0041] Preferably, after the oxidation reaction, the resulting system is filtered while hot, the filtrate is naturally cooled to room temperature, and then placed at 0 degrees Celsius for 30 min to 2 h. After filtration, the filter cake is washed with 1,4-dioxane 1 to 3 times, and then washed with dichloromethane 1 to 3 times. The amount of dichloromethane used is 50 to 100 mL / wash. The solvent is removed from the filtrate under reduced pressure to obtain 1,10-phenanthroline-2,9-dicarboxaldehyde.

[0042] In this invention, the 1,10-phenanthroline-2,9-dicarboxaldehyde is a brown solid product.

[0043] After obtaining 1,10-phenanthroline-2,9-dicarboxaldehyde, the present invention mixes the 1,10-phenanthroline-2,9-dicarboxaldehyde, acetonitrile, hydroxylamine hydrochloride, and triethylamine, and refluxes the mixture. After cooling, 1,8-diazabicycloundec-7-ene and p-toluenesulfonyl chloride (TsCl) are added to carry out a first substitution reaction to obtain 2,9-dicyano-1,10-phenanthroline. In the present invention, the mixing is preferably carried out under stirring conditions. In the present invention, the mixing preferably includes dissolving 1,10-phenanthroline-2,9-dicarboxaldehyde in a mixed solution of acetonitrile, hydroxylamine hydrochloride, and triethylamine. In the present invention, the reflux reaction temperature is preferably room temperature; the reflux reaction time is preferably 2-5 hours.

[0044] In this invention, the mass ratio of acetonitrile to 1,10-phenanthroline-2,9-dicarboxaldehyde is preferably 10-30:1, more preferably 20-25:1; the molar ratio of hydroxylamine hydrochloride to 1,10-phenanthroline-2,9-dicarboxaldehyde is preferably 2-5:1, more preferably 2-3:1; the molar ratio of triethylamine to 1,10-phenanthroline-2,9-dicarboxaldehyde is preferably 5-10:1, more preferably 6-7:1; the molar ratio of 1,8-diazabicycloundec-7-ene (DBU) to 1,10-phenanthroline-2,9-dicarboxaldehyde is preferably 3-10:1, more preferably 3-4:1; and the molar ratio of TsCl to 1,10-phenanthroline-2,9-dicarboxaldehyde is preferably 3-10:1, more preferably 3-4:1.

[0045] In this invention, the temperature of the first substitution reaction is preferably 90–140°C, more preferably 110–120°C; the time of the first substitution reaction is preferably 20–30 h, more preferably 24–28 h. In this invention, the first substitution reaction is preferably carried out under reflux conditions. In this invention, the first substitution reaction is preferably carried out under an inert atmosphere, specifically preferably under an argon atmosphere.

[0046] Preferably, after the first substitution reaction, the resulting system is filtered while hot, the solvent is removed from the filtrate under reduced pressure to obtain a brown solid, which is dispersed in methanol, filtered, washed with methanol 1 to 5 times (50 to 100 mL each time), washed with diethyl ether 1 to 5 times (50 to 100 mL each time), and dried under vacuum to obtain 2,9-dicyano-1,10-phenanthroline.

[0047] In this invention, the 2,9-dicyano-1,10-phenanthroline is a gray solid.

[0048] After obtaining 2,9-dicyano-1,10-phenanthroline, the present invention mixes the 2,9-dicyano-1,10-phenanthroline with hydrazine hydrate to carry out a second substitution reaction to obtain 1,10-phenanthroline-2,9-diaminohydrazone. In the present invention, the mixing is preferably carried out under stirring conditions.

[0049] In this invention, the mass ratio of hydrazine hydrate to 2,9-dicyano-1,10-phenanthroline is preferably 2 to 10:1, more preferably 2.5 to 8:1. In this invention, the purity of the hydrazine hydrate is preferably 85%.

[0050] In this invention, the temperature of the second substitution reaction is preferably room temperature; the time of the second substitution reaction is preferably 20-30 hours, more preferably 24-28 hours. In this invention, the second substitution reaction is preferably carried out in an inert atmosphere, specifically preferably in an argon atmosphere.

[0051] Preferably, after the second substitution reaction, the resulting system is filtered, the filter cake is washed with water and dried to obtain 1,10-phenanthroline-2,9-diaminohydrazone.

[0052] After obtaining 1,10-phenanthroline-2,9-diaminohydrazone, the present invention mixes the 1,10-phenanthroline-2,9-diaminohydrazone, 4-methylcamphorquinone, and toluene to carry out a third substitution reaction to obtain an o-phenanthroline-derived extractant with the structure shown in Formula I. In the present invention, the mixing is preferably carried out under stirring conditions. In the present invention, the mixing is preferably carried out under an inert atmosphere, specifically preferably under an Ar atmosphere.

[0053] In this invention, the molar ratio of 4-methylcamphorquinone to 1,10-phenanthroline-2,9-diaminohydrazone is preferably 2 to 5:1, more preferably 2 to 3:1; the mass ratio of toluene to 1,10-phenanthroline-2,9-diaminohydrazone is preferably 10 to 20:1, more preferably 16 to 18:1.

[0054] In this invention, the temperature of the third substitution reaction is preferably room temperature; the time of the third substitution reaction is preferably 20-30 hours, more preferably 24-28 hours. In this invention, the third substitution reaction is preferably carried out under reflux conditions. In this invention, the third substitution reaction is preferably carried out under an inert atmosphere, specifically preferably under an argon atmosphere.

[0055] Preferably, after the third substitution reaction, the resulting system is filtered, the solvent is removed from the filtrate under reduced pressure, purified by column chromatography, and eluted to obtain the o-phenanthroline-derived extractant with the structure shown in Formula I. In this invention, the eluent used for column chromatography purification is preferably a mixed solvent of dichloromethane and ethyl acetate; the volume ratio of dichloromethane to ethyl acetate in the mixed solvent is preferably 5–20:1, more preferably 10:1.

[0056] In this invention, the o-phenanthroline-derived extractant of the structure shown in Formula I is a pale yellow solid.

[0057] In this invention, the synthetic route of the o-phenanthroline-derived extractant is as follows:

[0058]

[0059] This invention provides the application of the o-phenanthroline-derived extractant described in the above technical solution or the o-phenanthroline-derived extractant prepared by the preparation method described in the above technical solution in the separation of trivalent lanthanum and actinium, preferably applied in the separation process of trivalent lanthanum and actinium in the nuclear fuel cycle.

[0060] In this invention, the preferred application includes: mixing a diluent containing an extractant with an aqueous nitric acid solution containing trivalent lanthanum and actinium, and performing extraction separation; the extractant is the o-phenanthroline-derived extractant described in the above technical solution or the o-phenanthroline-derived extractant prepared by the preparation method described in the above technical solution.

[0061] In this invention, the concentration of the extractant in the diluent is preferably 1–50 mmol / L, more preferably 10–50 mmol / L. In this invention, the diluent is preferably one or more of n-octanol, 3-nitro-trifluorotoluene, dichloromethane, chloroform, and cyclohexanone, more preferably n-octanol.

[0062] In this invention, the concentration of nitric acid in the nitric acid aqueous solution containing trivalent lanthanum-actinium is preferably 0.1–4 mol / L, more preferably 0.5–3 mol / L. In this invention, the concentration of trivalent lanthanum in the nitric acid aqueous solution containing trivalent lanthanum-actinium is preferably 10 mol / L. -13 ~100 mmol / L, more preferably 1~10 mmol / L; the concentration of trivalent actinium is preferably 10 -13~10 mmol / L, more preferably 10 -13 ~10 -6 mmol / L.

[0063] In this invention, the nitric acid aqueous solution containing trivalent lanthanum and actinium preferably further includes a salting-out agent. In this invention, the salting-out agent is preferably sodium nitrate. In this invention, the concentration of the salting-out agent in the nitric acid aqueous solution containing trivalent lanthanum and actinium is preferably 0.1–3.0 mol / L, more preferably 0.5–1.0 mol / L.

[0064] In this invention, the volume ratio of the diluent containing the extractant to the aqueous nitric acid solution containing trivalent lanthanum and actinium is preferably 1 to 1000:1, more preferably 1 to 10:1.

[0065] In this invention, the extraction and separation temperature is preferably room temperature; the extraction and separation preferably includes sequential shaking and centrifugation. In this invention, the shaking time is preferably 5-60 min, more preferably 10-30 min. In this invention, the centrifugation speed is preferably 5000-10000 r / min, more preferably 6000 r / min; the centrifugation time is preferably 3-10 min, more preferably 5 min.

[0066] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0067] The americium nitrate and europium nitrate used in the extraction experiment were sourced from the China Institute of Atomic Energy.

[0068] Example 1

[0069] The synthetic route for preparing the o-phenanthroline-derived extractant in this embodiment is as follows:

[0070]

[0071] S1: Under stirring conditions, 10.0 g of 2,9-dimethyl-1,10-phenanthroline (1) was dissolved in 1,4-dioxane (150 mL), and 10.7 g of selenium dioxide (oxidant) was added. The mixture was refluxed at 110 °C for 40 min. The mixture was filtered while hot, and the filtrate was allowed to cool naturally to room temperature. Then it was placed at 0 °C for 1 h and filtered. The filter cake was washed twice with 50 mL of 1,4-dioxane and then twice with 50 mL of dichloromethane. The solvent was removed from the filtrate under reduced pressure to obtain the brown solid product 1,10-phenanthroline-2,9-dicarboxaldehyde (2).

[0072] S2: Under stirring conditions, 1,10-phenanthroline-2,9-dicarboxaldehyde (2) (8.1 g) was dissolved in a mixed solution of acetonitrile (200 mL), hydroxylamine hydrochloride (5.2 g), and triethylamine (31 mL). The mixture was refluxed at room temperature for 3 h. After cooling, 1,8-diazabicycloundec-7-ene (DBU, 15.5 g) and TsCl (21.4 g) were added. The mixture was refluxed at 110 °C for 24 h. The mixture was filtered while hot, and the solvent was removed from the filtrate under reduced pressure to obtain a brown solid. The solid was dispersed in methanol, filtered, washed three times with methanol (50 mL each time), washed three times with diethyl ether (50 mL each time), and dried under vacuum to obtain a gray solid 2,9-dicyano-1,10-phenanthroline (3).

[0073] S3: Under stirring conditions, 2,9-dicyano-1,10-phenanthroline (3) (5.5 g) was dissolved in hydrazine hydrate (14.1 g, 85%), reacted at room temperature for 24 h, filtered, the filter cake was washed with water and dried to obtain product 1,10-phenanthroline-2,9-diaminohydrazone (4).

[0074] S4: Under stirring conditions and an Ar atmosphere, 1,10-phenanthroline-2,9-diaminohydrazone (4) (2.9 g) and 4-methylcamphorquinone (5) (3.6 g) were dissolved in toluene (50 mL), and the mixture was refluxed at room temperature for 24 h. The mixture was filtered, and the solvent was removed from the filtrate under reduced pressure. The filtrate was purified by column chromatography (eluent was dichloromethane:ethyl acetate = 10:1 (v:v)) to obtain a pale yellow solid o-phenanthroline-derived extractant (6).

[0075] Figure 1 and Figure 2 The 1H and 1C NMR spectra of the o-phenanthroline-derived extractant (6) prepared in this embodiment are respectively obtained from... Figure 1 and Figure 2 It can be seen that the structure of the final product prepared in this embodiment is the target compound.

[0076] Figure 3 Mass spectrometry of the o-phenanthroline-derived extractant (6) prepared in this embodiment, HRMS(EI) m / z calcd for C 36 H 39 N8[M+H] + :583.3292;Found:583.3286.

[0077] Figure 3 The value of 583.3286 (M / Z mass-to-charge ratio) represents the mass-to-charge ratio of the compound after hydrogenation, further indicating that the final product structure prepared in this embodiment is the target compound.

[0078] Extraction Experiment 1

[0079] In the extraction experiment, the lanthanum-actinium separation and extraction system consisted of an organic phase and an aqueous phase. The organic phase contained the diluent n-octanol and the o-phenanthroline-derived extractant (6) prepared in Example 1 (the concentration of the extractant was 10 mmol / L); the aqueous phase was an aqueous solution with a nitric acid concentration of 0.01–4 mol / L. 241 Am(III) and 152 The initial activity of Eu(III) was 3000 Bq / mL, corresponding to the following concentration: 241 Am(III) is 1×10 -10 mmol / L 152 Eu(III) is 3.33 × 10 -12 mmol / L. Among them 241 Am(III) represents the trivalent actinide elements. 152 Eu(III) represents the trivalent lanthanide elements.

[0080] The above 1 mL organic phase was mixed with 1 mL of aqueous phase with different nitric acid concentrations (0.01–4 mol / L), and the mixture was shaken at 25 °C for 60 min. After centrifugation at 6000 r / min for 5 min, the aqueous and organic phases were separated. Samples were taken and analyzed using a high-purity germanium gamma-ray spectrometer. 241 Am(III) and 152 The activity of Eu(III) was calculated, and the distribution ratio D (D = C) was determined. 有 / C 水 After equilibrium, the ion activity C of the organic phase 有 Residual ion activity C in aqueous phase 水 The ratio of (SF=D) and the separation factor (SF=D) Am / D Eu The result is as follows Figure 4 As shown.

[0081] In 0.1–4 mol / L nitric acid solution, the o-phenanthroline-derived extractant prepared in Example 1 was effective against… 241 The allocation coefficient D of Am(III) is above 200, and at its highest it approaches 1000. 241 Am is greater than 99%. 241 Am(III) and 152 The separation coefficient between Eu(III) is greater than 200, and approaches 1000 in 0.5 mol / L nitric acid solution. These results indicate that the o-phenanthroline-derived extractant prepared in Example 1 exhibits good separation performance and application prospects for trivalent lanthanum actinide in a wide range of molar nitric acid solutions.

[0082] Extraction Experiment 2

[0083] In the extraction experiment, the lanthanum-actinium separation and extraction system consisted of an organic phase and an aqueous phase. The organic phase contained the diluent n-octanol and the o-phenanthroline-derived extractant (6) prepared in Example 1 (the concentration of the extractant was 10 mmol / L). The aqueous phase was an aqueous solution of nitric acid with a concentration of 1 mol / L. 241 Am(III) and 152 The initial activity of Eu(III) was 3000 Bq / mL, corresponding to the following concentration: 241 Am(III) is 1×10 -10 mmol / L 152 Eu(III) is 3.33 × 10 -12 mmol / L. Among them 241 Am(III) represents the trivalent actinide elements. 152 Eu(III) represents the trivalent lanthanide elements.

[0084] Mix 1 mL of organic phase and 1 mL of aqueous phase, shake at 25 °C for 1–60 min, then centrifuge at 6000 r / min for 5 min to separate the aqueous and organic phases. Samples were taken and analyzed using a high-purity germanium gamma-ray spectrometer. 241 Am(III) and 152 The activity of Eu(III) was calculated, and the distribution ratio D (D = C) was determined. 有 / C 水 After equilibrium, the ion activity C of the organic phase 有 Residual ion activity C in aqueous phase 水 The ratio), the result is as follows Figure 5 As shown.

[0085] The o-phenanthroline-derived extractant (6) prepared in Example 1 was used for... 241 The extraction efficiency of Am(III) reached extraction equilibrium after a shaking time of 5 min, and its partition ratio D Am Reached 890; 152 The extraction of Eu(III) reached equilibrium at 20 min, and its partition ratio D Eu Close to but less than 1 241 Am(III) and 152 The separation coefficient between Eu(III) groups is close to 1000. Rapid extraction kinetics, for... 241 Am(III) has high extraction capacity, 241 Am(III) and 152 The large separation coefficient between Eu(III) indicates that the o-phenanthroline-derived extractant prepared in Example 1 has good separation effect and application prospects for trivalent lanthanum actinide in nitric acid solution.

[0086] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. The application of an o-phenanthroline-derived extractant in the separation of trivalent lanthanum actinium, characterized in that, The application includes: mixing a diluent containing an extractant with an aqueous nitric acid solution containing trivalent lanthanum-actinium, and performing extraction separation; the extractant is an o-phenanthroline-derived extractant, and the concentration of nitric acid in the aqueous nitric acid solution containing trivalent lanthanum-actinium is 0.1~4 mol / L; the o-phenanthroline-derived extractant has the structure shown in Formula I: Formula I.

2. The application according to claim 1, characterized in that, The preparation method of the o-phenanthroline-derived extractant includes the following steps: 2,9-Dimethyl-1,10-phenanthroline, 1,4-dioxane and an oxidant were mixed and oxidized to obtain 1,10-phenanthroline-2,9-dicarboxaldehyde. The 1,10-phenanthroline-2,9-dicarboxaldehyde, acetonitrile, hydroxylamine hydrochloride and triethylamine were mixed and subjected to reflux reaction. After cooling, 1,8-diazabicycloundec-7-ene and p-toluenesulfonyl chloride were added to carry out the first substitution reaction to obtain 2,9-dicyano-1,10-phenanthroline. The 2,9-dicyano-1,10-phenanthroline and hydrazine hydrate were mixed and subjected to a second substitution reaction to obtain 1,10-phenanthroline-2,9-diaminohydrazone; The 1,10-phenanthroline-2,9-diaminohydrazone, 4-methylcamphorquinone, and toluene were mixed and subjected to a third substitution reaction to obtain an o-phenanthroline-derived extractant with the structure shown in Formula I.

3. The application according to claim 2, characterized in that, The oxidation reaction is carried out at a temperature of 90–140°C and for a duration of 30 min–5 h.

4. The application according to claim 2, characterized in that, The temperature of the first substitution reaction is 90~140℃; the time of the first substitution reaction is 20~30h.

5. The application according to claim 2, characterized in that, The second substitution reaction was carried out at room temperature for 20-30 hours.

6. The application according to claim 2, characterized in that, The third substitution reaction was carried out at room temperature for 20-30 hours.

7. The application according to claim 1, characterized in that, The concentration of the extractant in the diluent is 1~50 mmol / L.

8. The application according to claim 1, characterized in that, The nitric acid aqueous solution containing trivalent lanthanum and actinium also includes a salting-out agent.

Images