DAPhen ligand, preparation method and application thereof, and method for separating lanthanides and actinides from waste liquid

Abstract

The invention provides a DAPhen ligand, a preparation method and application thereof, and a method for separating lanthanide elements and actinide elements from waste liquid, and belongs to the technical field of extraction separation. Starting from the molecular structure design of the ligands, the novel DAPhen ligands are developed by designing the structures of the ligands, the ligands ensure the high distribution ratio of Eu, meanwhile, the introduction of the water-soluble ligands also ensures the efficient reverse extraction of Am, the lanthanum actinide separation factor SFEu / Am of the four DAPhen ligands is up to 320, and the separation effect is good. In addition, the ligand is good in water solubility and extraction kinetics, and balance can be achieved within 10 min. The invention provides a new thought for deeply understanding lanthanum actinide separation, and provides technical support for establishing an advanced spent nuclear fuel post-treatment system and efficiently utilizing minor actinide elements.

Description

Technical Field

[0001] The invention relates to the technical field of extraction and separation, in particular to a DAPhen ligand and a preparation method and application thereof, and a method for separating lanthanides and actinides from waste liquid. Background Art

[0002] Nowadays, the development of nuclear energy is one of the important ways to solve energy problems, especially for those areas lacking power resources. However, while nuclear energy has made great contributions to mankind, it has also produced a large amount of radioactive waste, which poses direct or potential hazards to human development and the environment. Therefore, the proper treatment and disposal of radioactive waste has become an issue that all countries pay special attention to, and it is also one of the key factors affecting the sustainable development of nuclear energy. The safe treatment and disposal of high-level radioactive liquid waste (HLLW) is the key to the treatment and disposal of radioactive waste.

[0003] Solvent extraction is the most commonly used separation method for extracting and separating rare earth elements, and separating and recovering lanthanide and actinide elements in the nuclear industry. Solvent extraction utilizes the different solubility of complexes of different lanthanide ions and actinide ions in the organic phase and the aqueous phase, resulting in different distribution coefficients, to extract various rare earth ions. This method has gradually replaced the traditional fractional crystallization method and ion exchange method.

[0004] The related solvent extraction method for separating lanthanides and actinides has the problems of low separation factor and poor separation effect. Summary of the invention

[0005] In view of this, the object of the present invention is to provide a DAPhen ligand and its preparation method and application, and a method for separating lanthanides and actinides from waste liquid. The separation factor SF of the DAPhen ligand of the present invention for lanthanides and actinides is Eu / Am High, good separation effect.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] The present invention provides a DAPhen ligand having a structure shown in Formula I:

[0008]

[0009] In Formula I, R1 and R2 are independently "~~" in R1 and R2 indicates a connection site.

[0010] Preferably, the DAPhen ligand has a structure shown in any one of formulas L-1 to L-4:

[0011]

[0012] The present invention also provides a method for preparing the DAPhen ligand described in the above technical solution, comprising the following steps:

[0013] Mixing 2,9-dicarboxylic acid-1,10-phenanthroline, an organic solvent and an acidic substance for reflux reaction to obtain dimethyl 2,9-dicarboxy-1,10-phenanthroline;

[0014] The dimethyl 2,9-dicarboxy-1,10-phenanthroline, a substitution raw material and an organic solvent are mixed for a substitution reaction to obtain the DAPhen ligand; the substitution raw material includes one or more of 3-amino-1-propanol, 3-amino-1,2-propylene glycol, 2-(2-aminoethoxy)ethanol and 2-(2-(2-aminoethoxy)ethoxy)ethanol.

[0015] Preferably, the reflux reaction is carried out at a temperature of 60 to 100° C. and for a time of 6 to 12 hours.

[0016] Preferably, the temperature of the substitution reaction is 60-80° C. and the time is 6-12 hours.

[0017] The present invention also provides the use of the DAPhen ligand described in the above technical solution in separating lanthanides and actinides.

[0018] The present invention also provides a method for separating lanthanides and actinides from waste liquid, comprising the following steps:

[0019] The waste liquid is mixed with an extractant for solvent extraction, wherein the extractant is the DAPhen ligand described in the above technical solution, and the waste liquid contains lanthanide elements and actinide elements.

[0020] Preferably, the lanthanide element includes europium, and the actinide element includes americium.

[0021] Preferably, the acidity of the waste liquid is 0.01-1.5M.

[0022] Preferably, the concentration of the DAPhen ligand in the system during the solvent extraction is 2.5-40 mM.

[0023] The present invention provides a DAPhen ligand having a structure shown in Formula I. Compared with the prior art, the present invention has the following beneficial effects:

[0024] The present invention starts with the design of the ligand molecular structure, and develops a new DAPhen ligand by designing the structure of the ligand. The ligand not only ensures a high distribution ratio for Eu, but also the introduction of the water-soluble ligand also ensures efficient stripping of Am. The lanthanum-actinium separation factor SF of the DAPhen ligand isEu / Am As high as 320, the separation effect is good. In addition, the ligand has good water solubility and extraction kinetics, and equilibrium can be reached in 10 minutes. The present invention provides a new idea for in-depth understanding of lanthanum and actinium separation, and provides technical support for establishing an advanced spent nuclear fuel reprocessing system and efficiently utilizing minor actinide elements.

[0025] The present invention also provides a method for preparing the DAPhen ligand described in the above technical solution. The preparation method of the present invention is simple and easy to industrialize. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a reaction schematic diagram for preparing DAPhen ligands of formulas L-1 to L-4 in the examples;

[0027] Figure 2 is the acidity test curve of HP-DAPhen;

[0028] Figure 3 is the ligand concentration extraction curve of HP-DAPhen;

[0029] Figure 4 is the kinetic test curve of HP-DAPhen;

[0030] Figure 5 is the acidity test curve of DHP-DAPhen;

[0031] Figure 6 is the ligand concentration extraction curve of DHP-DAPhen;

[0032] Figure 7 It is the kinetic test curve of DHP-DAPhen;

[0033] Figure 8 is the acidity test curve of AE-DAPhen;

[0034] Fig. 9 is the ligand concentration extraction curve of AE-DAPhen;

[0035] Fig.10 is the kinetic test curve of AE-DAPhen;

[0036] Fig.11 is the acidity test curve of AEE-DAPhen;

[0037] Fig.12 is the ligand concentration extraction curve of AEE-DAPhen;

[0038] Fig.13 This is the kinetic test curve of AEE-DAPhen. DETAILED DESCRIPTION

[0039] The present invention provides a DAPhen ligand having a structure shown in Formula I:

[0040]

[0041] In Formula I, R1 and R2 are independently "~~" in R1 and R2 indicates a connection site.

[0042] In the present invention, the DAPhen ligand preferably has a structure shown in any one of formulas L-1 to L-4:

[0043]

[0044] The present invention also provides a method for preparing the DAPhen ligand described in the above technical solution, comprising the following steps:

[0045] Mixing 2,9-dicarboxylic acid-1,10-phenanthroline, an organic solvent and an acidic substance for reflux reaction to obtain dimethyl 2,9-dicarboxylic acid-1,10-phenanthroline;

[0046] The dimethyl 2,9-dicarboxy-1,10-phenanthroline, a substitution raw material and an organic solvent are mixed for a substitution reaction to obtain the DAPhen ligand; the substitution raw material includes one or more of 3-amino-1-propanol, 3-amino-1,2-propylene glycol, 2-(2-aminoethoxy)ethanol and 2-(2-(2-aminoethoxy)ethoxy)ethanol.

[0047] In the present invention, unless otherwise specified, the raw materials used are all commercially available products in the art.

[0048] The invention mixes 2,9-dicarboxylic acid-1,10-phenanthroline, an organic solvent and an acidic substance and performs a reflux reaction to obtain dimethyl 2,9-dicarboxy-1,10-phenanthroline.

[0049] In the present invention, the organic solvent is preferably methanol (MeOH).

[0050] In the present invention, the usage ratio of the 2,9-dicarboxylic acid-1,10-phenanthroline to the organic solvent is preferably 18.64 mmol:15 mL.

[0051] In the present invention, the acidic substance is preferably concentrated sulfuric acid, and the mass percentage of the concentrated sulfuric acid is preferably 95% to 98%.

[0052] In the present invention, the usage ratio of the 2,9-dicarboxylic acid-1,10-phenanthroline to concentrated sulfuric acid is preferably 18.64 mmol:2 mL.

[0053] In the present invention, the reflux reaction temperature is 60-100°C, specifically 60, 70, 80, 90 or 100°C, and the time is preferably 6-12h, specifically 6, 7, 8, 9, 10, 11 or 12h.

[0054] In a specific embodiment of the present invention, the 2,9-dicarboxylic acid-1,10-phenanthroline and methanol are added to a round-bottom flask, a magnetic bar is added, and then concentrated sulfuric acid is added dropwise to the reaction mixture, and the resulting reaction mixture is heated to perform the reflux reaction. After the reflux reaction is completed, it is naturally cooled to room temperature, and then a saturated NaHCO3 solution is added to neutralize it. Subsequently, an ice-water mixture is added to the flask to crystallize the mixture, filtered, and then washed with pure water and ethanol in turn, and then vacuum dried to obtain the dimethyl 2,9-dicarboxy-1,10-phenanthroline.

[0055] After obtaining dimethyl 2,9-dicarboxyl-1,10-phenanthroline, the present invention mixes the dimethyl 2,9-dicarboxyl-1,10-phenanthroline, a substitution raw material and an organic solvent to carry out a substitution reaction to obtain the DAPhen ligand; the substitution raw material includes one or more of 3-amino-1-propanol, 3-amino-1,2-propylene glycol, 2-(2-aminoethoxy)ethanol and 2-(2-(2-aminoethoxy)ethoxy)ethanol.

[0056] In the present invention, the temperature of the substitution reaction is preferably 60-80°C, specifically 60, 65, 70, 75 or 80°C, and the time is preferably 6-12h, specifically 6, 7, 8, 9, 10, 11 or 12h.

[0057] In the present invention, the substitution reaction preferably further includes post-treatment to obtain the DAPhen ligand.

[0058] In the present invention, the post-treatment preferably includes one or more of rotary evaporation, washing, column chromatography purification and drying. The present invention has no particular limitation on the specific parameters of the post-treatment, as long as the DAPhen ligand can be obtained.

[0059] The present invention also provides the use of the DAPhen ligand described in the above technical solution in separating lanthanides and actinides.

[0060] The present invention also provides a method for separating lanthanides and actinides from waste liquid, comprising the following steps:

[0061] The waste liquid is mixed with an extractant for solvent extraction, wherein the extractant is the DAPhen ligand described in the above technical solution, and the waste liquid contains lanthanide elements and actinide elements.

[0062] In the present invention, the waste liquid is preferably high-level waste liquid, which refers to waste liquid with a radioactivity greater than 3.7×10 10 The radioactive waste liquid of 100 Bq / L is preferably derived from the raffinate water phase of the co-decontamination circulation section of the spent fuel reprocessing plant, and the acidity of the high-level waste liquid is preferably 3-4M.

[0063] In the present invention, the lanthanide element includes europium (Eu), and the actinide element includes americium (Am).

[0064] In the present invention, the acidity of the waste liquid is preferably 0.01 to 4 M, specifically 0.01, 0.05, 0.10, 0.25, 0.5, 0.75, 1.0, 1.25, 1.5, 3 or 4 M. In the present invention, nitric acid is preferably used to adjust the acidity of the waste liquid.

[0065] In the present invention, the concentration of DAPhen ligand in the system during solvent extraction is 2.5-40mM, specifically: L-1: 2.5, 5, 10, 20 and 25mM; L-2: 2.5, 5, 10, 20, 25 and 30mM; L-3: 2.5, 5, 10, 20, 25, 30 and 40mM; L-4: 2.5, 5, 10, 20, 25 and 30mM.

[0066] In the present invention, the temperature of the solvent extraction is preferably room temperature, and the time is preferably 5 to 60 minutes, specifically 5, 10, 15, 30, 45 or 60 minutes.

[0067] In the present invention, the solvent extraction is preferably carried out under stirring conditions, and the stirring speed is preferably 3000 rpm.

[0068] The technical solutions in the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0069] Example 1

[0070] 1. Prepare DAPhen ligands represented by formulas L-1 to L-4;

[0071] a: dimethyl 2,9-dicarboxy-1,10-phenanthroline

[0072]

[0073] 2,9-dicarboxylic acid-1,10-phenanthroline (5g, 18.64mmol) and 15mL methanol were added to a 250mL round-bottom flask, a magnetic bar was added, and then 2mL concentrated sulfuric acid (98wt%) was slowly added dropwise to the reaction mixture. The reaction mixture was heated to 100℃ and refluxed for 6h, cooled to room temperature, and then neutralized by adding saturated NaHCO3 solution. Subsequently, 60mL of ice-water mixture was added to the flask to crystallize the mixture, filtered, and then washed with pure water (5×20mL) and ethanol (5×20mL). After drying under vacuum at 70℃, 4.1g of off-white solid product was obtained (yield 75%).

[0074] 1 H NMR (400MHz, DMSO) δ (ppm): 8.73-8.71 (d, J = 8.3Hz, 2H), 8.40-8.38 (d, J = 8.2Hz, 2H), 8.18 (s, 2H), 4.02 (s, 6H); 13 C NMR (400MHz, DMSO) δ (ppm): 165.52 (2C), 147.68 (2C), 145.06 (2C), 138.08 (2C), 130.58 (2C), 128.54 (2C), 123.70 (2C), 52.74 (2C); MS (ESI + )m / z calcd.for[M+H] + :297.09,found:297.0869;MS(ESI + )m / z calcd.for[M+Na] + :319.07,found:319.0688;MS(ESI + )m / z calcd.for[2M+Na] + :615.15,found:615.1493.

[0075] b: L-1 (HP-DAPhen)

[0076]

[0077] Add dimethyl 2,9-dicarboxylic acid-1,10-phenanthroline (2g, 6.75mmol) and 3-amino-1-propanol (1.08g, 14.18mmol) to a 100mL round-bottom flask, add 30mL methanol and an appropriate magnetic particle. After heating and stirring at 75°C for 12h, the solvent is removed by rotary evaporation, and the crude product is washed with ethanol (3×20mL). After vacuum drying at 70°C, the white solid product is 2.12g (yield 82%).

[0078] Elemental Analysis calcd.for:C,62.82;H,5.80;N,14.65;O,16.73,Found:C,62.94;H,5.57;N,13.23; 1 H NMR (400MHz, DMSO) δ (ppm): 9.46-9.43 (m, 2H), 8.72-8.70 (d, J = 8.3Hz, 2H), 8.45-8.43 (d, J = 8.2H) z,2H),8.15(s,2H),4.80-4.77(m,2H),3.65-3.61(m,4H),3.58-3.53(m,4H),1.87-1.81(m,4H); 13 C NMR(400MHz,DMSO)δ(ppm):163.58(2C),149.60(2C),143.58(2C),138.16(2C),1 30.13(2C),127.78(2C),120.87(2C),59.57(2C),37.25(2C),32.04(2C); MS(ESI + )m / z calcd.for[M+H] + :383.17,found:383.1708;MS(ESI + )m / z calcd.for[M+Na] + :405.15,found:405.1532; HRMS(ESI + )m / z calcd.for[M+H] + :383.17,found:383.1708; HRMS(ESI + )m / z calcd.for[M+Na] + :405.15,found:405.1532.

[0079] L-2(DHP-DAPhen)

[0080]

[0081] Dimethyl 2,9-dicarboxylic acid-1,10-phenanthroline (1 g, 3.38 mmol) and 3-amino 1,2-propanediol (0.66 g, 7.09 mmol) were added to a 100 mL round-bottom flask, and 10 mL of MeOH and a suitable stirring rod were added. After heating and stirring at 75 ° C for 12 h, the solvent was removed by a rotary evaporator, and the crude product was washed with ethanol (3×10 mL). After vacuum drying at 70 ° C, the white solid product was 1.17 g (yield was 84%).

[0082] Elemental Analysis calcd.for:C,57.97;H,5.35;N,13.52;O,23.16,Found:C,56.70;H,5.14;N,11.87; 1 H NMR(400MHz,DMSO)δ(ppm):9.22-9.19(m,2H),8.72-8.70(d,J=8.3Hz,2H),8.44-8.42(d,J=8.2Hz,2H),8.15(s,2H),5.16(s,2H),4.88(s,2H),3.82-3.81(d,J=5.5Hz,2H),3.66-3.60(m,2H),3.56-3.44(m,6H); 13 C NMR(600MHz,DMSO)δ(ppm):163.67(2C),149.32(2C),143.42(2C),138.32(2C),130.20(2C),127.86(2C),120.86(2C),70.01(2C),64.39(2C),42.91(2C);MS(ESI + )m / z calcd.for[M+H] + :415.16,found:415.1604;MS(ESI + )m / z calcd.for[M+Na] + :437.14,found:437.1427;MS(ESI + )m / zcalcd.for[M+K] + :453.12,found:453.1159;MS(ESI + )m / z calcd.for[2M+Na] + :851.30,found:851.2962;HRMS(ESI + )m / z calcd.for[M+H] + :415.16,found:415.1604;HRMS(ESI + )m / z calcd.for[M+Na] + :437.14,found:437.1427;HRMS(ESI + )m / z calcd.for[M+K] + :453.12,found:453.1159.

[0083] L-3(AE-DAPhen)

[0084]

[0085] Dimethyl 2,9-dicarboxylic acid-1,10-phenanthroline (1g, 3.38mmol,) and 2-(2-aminoethoxy)ethanol (0.76g, 7.09mmol) were added to a 100mL round-bottom flask, and 10mL MeOH and a stirring rod were added. After heating and stirring at 75°C for 12h, the solvent was removed by a rotary evaporator, and the raw material was washed with ethanol (3×20mL) to obtain 0.90g of the first part of pure white product. The filtrate was evaporated and purified by column chromatography using 10vol% methanol in dichloromethane as the mobile phase (rf=0.41) to obtain 0.40g of the second part of the product. The two parts were collected together and dried under vacuum at 70°C. The white solid product was 1.27g (yield 85%).

[0086] Elemental Analysis calcd.for:C,59.72;H,5.92;N,12.66;O,21.69,Found:C,58.78;H,5.76;N,11.43; 1 H NMR (400MHz, DMSO) δ (ppm): 9.38 (s, 2H), 8.74-8.72 (d, J = 7.4Hz, 2H), 8.46-8.44 (d ,J=7.3Hz,2H),8.18(s,2H),4.66(s,2H),3.70-3.66(d,J=20Hz,8H),3.52(s,8H); 13 C NMR (400MHz, DMSO) δ (ppm): 164.54 (2C), 150.16 (2C), 144.22 (2C), 138.80 (2C), 130.81 (2C),128.47(2C),121.64(2C),100.01(2C),72.59(2C),69.35(2C),60.76(2C); MS(ESI + )m / z calcd.for[M+H] + :443.19,found:443.1924;MS(ESI + )m / zcalcd.for[M+Na] + :465.18,found:465.1747;MS(ESI + )m / z calcd.for[2M+Na] + :907.36,found:907.3614; HRMS(ESI +)m / z calcd.for[M+H] + :443.19,found:443.1924; HRMS(ESI + )m / z calcd.for[M+Na] + :465.18,found:465.1747.

[0087] L-4(AEE-DAPhen)

[0088]

[0089] Dimethyl 2,9-dicarboxylic acid-1,10-phenanthroline (Compound 1, 1 g, 3.38 mmol) and 2-(2-(2-aminoethoxy)ethoxy)ethanol (1.08 g, 7.09 mmol) were added to a 100 mL round-bottom flask, and 10 mL of MeOH and a suitable stirring rod were added. After heating and stirring at 75 ° C for 12 h, the solvent was removed by a rotary evaporator, and chromatographic purification was performed using 10 vol% MeOH in DCM as the mobile phase (rf = 0.39) to obtain 1.43 g of a white oily product (yield of 80%).

[0090] Elemental Analysis calcd.for:C,58.86;H,6.46;N,10.56;O,24.12, Found:C,56.38;H,6.42;N,9.46; 1 H NMR (400MHz, DMSO) δ (ppm): 9.37-9.34 (m, 2H), 8.73-8.71 (d, J = 8.3Hz, 2H), 8.46-8.44 (d, J = 8.3Hz, 2H), 8.16 (s, 2H) ,4.55-4.52(m,2H),3.72-3.69(m,4H),3.66-3.63(m,4H),3.62-3.59(m,4H),3.56-3.54(m,4H),3.44-3.40(m,8H); 13 C NMR (400MHz, DMSO) δ (ppm): 164.03 (2C), 149.60 (2C), 143.68 (2C), 138.27 (2C), 130.28 (2C), 127.94(2C),121.10(2C),72.36(2C),69.73(2C),69.61(2C),68.81(2C),60.19(2C); MS(ESI + )m / z calcd.for[M+H] + :531.25,found:531.2444,MS(ESI+ )m / z calcd.for[M+K] + :569.20found:569.2002; HRMS(ESI + )m / z calcd.for[M+H] + :531.25,found:531.2444,HRMS(ESI + )m / z calcd.for[M+K] + :569.20found:569.2002.

[0091] 2. Solvent extraction test

[0092] Solvent extraction

[0093] The HNO3 used was analytically pure. The deionized water used had a low conductivity (18.2 MΩ). The 241Am tracer (americium tracer) used was from the Institute of Nuclear and New Energy Technology, Tsinghua University, with a radioactivity concentration of 1×10 7 cpm / mL. Radioactive europium tracers containing 152Eu and 154Eu were obtained from the Institute of Nuclear and New Energy Technology of Tsinghua University, with a total radioactivity concentration of 1.6×10 7 cpm / mL.

[0094] All ligands were tested by elemental analysis and the purity of the ligands was determined taking into account the water content. Ligand 1 had a purity of 90 wt%. Ligand 2 had a purity of 91 wt%. Ligand 3 had a purity of 92 wt%. Ligand 4 had a purity of 92.8 wt%.

[0095] All aqueous phases contained ligand, 241Am and 152Eu / 154Eu tracers and different concentrations of HNO3.

[0096] All extraction experiments were performed in 4 mL polypropylene screw cap vials with rubber "O" rings to prevent leakage / contamination. The activities of 241Am and 152 / 154Eu were counted using a Quantulus 1220 (PerkinElmer) liquid scintillation counter.

[0097] 2.2 Stock solution

[0098] The ligand stock solution was prepared by dissolving 136 mg of HP-DAPhen ligand (purity: 90 wt%) in 8 mL of pure water to a concentration of 40 mM.

[0099] The ligand stock solution was prepared by dissolving 145.7 mg of DHP-DAPhen ligand (purity: 91 wt%) in 8 mL of pure water to a concentration of 40 mM.

[0100] The ligand stock solution was prepared by dissolving 153.9 mg of AE-DAPhen ligand (purity: 92 wt%) in 8 mL of pure water to a concentration of 40 mM.

[0101] The ligand stock solution was prepared by dissolving 183 mg of AEE-DAPhen ligand (purity: 92.8 wt%) ligand in 8 mL of pure water to a concentration of 40 mM.

[0102] A stock solution of 241Am(NO3)3 containing 0.01M nitric acid.

[0103] 152 / 154Eu(NO3)3 stock solution containing 0.01M nitric acid.

[0104] HNO3 stock solutions are 1M, 4M and 8M.

[0105] 0.2M TODGA (N,N,N′,N′-tetraoctyl-3-oxoglutaramide) organic phase: 3.521 g TODGA was dissolved in 30 mL kerosene / n-octanol (95:5, v / v) solution; the structure of TODGA is shown below:

[0106]

[0107] 2.3 Three types of tests:

[0108] 2.3.1 Acidity test to determine the effect of nitric acid concentration on distribution ratio and SF Eu / Am impact.

[0109] For all ligands, acidity studies were performed at 0.01, 0.05, 0.10, 0.25, 0.5, 0.75, 1.0, 1.25, 1.5 M nitric acid, with a standard concentration of 10 mM.

[0110] 2.3.2 Kinetic studies to determine the kinetics of the extraction process.

[0111] The aqueous phase contained a constant concentration of ligand (10 mM) and 0.75 M nitric acid, and the test was performed at intervals of 5, 10, 15, 30, 45 and 60 min.

[0112] 2.3.3 Ligand concentration extraction studies to determine the effect of ligand concentration on partition ratio and SF Eu / Am The acidity is constant at 0.75M nitric acid.

[0113] HP-DAPhen: 2.5, 5, 10, 20 and 25 mM;

[0114] DHP-DAPhen: 2.5, 5, 10, 20, 25 and 30 mM;

[0115] AE-DAPhen: 2.5, 5, 10, 20, 25, 30 and 40 mM;

[0116] AEE-DAPhen: 2.5, 5, 10, 20, 25 and 30 mM.

[0117] Each 1 mL of aqueous phase and 1 mL of organic phase were mixed in a PP vial, shaken using a vortex oscillator (standard 30 min), and then centrifuged (3000 rpm, 2 min) to completely separate the two phases. Samples from the aqueous and organic phases were then collected, and the radioactivity in different channels was counted using LSC, which could distinguish the α radioactivity of 241Am and the β radioactivity of 152Eu / 154Eu. To ensure the accuracy of the data, each sample was measured for at least 5 min. The count ratios in the two phases were then interpreted as the extraction parameters D Am and D Eu , while SF Eu / Am Then calculate D Eu / D Am Compare.

[0118] 2.3 Solvent extraction results

[0119] Figure 2 is the acidity test curve of HP-DAPhen, Figure 3 is the ligand concentration extraction curve of HP-DAPhen, Figure 4 The kinetic test curve of HP-DAPhen shows that the best acidity for HP-DAPhen is 0.50-1.0M, and the separation effect is good. Eu / Am The equilibrium time is good, less than 10 minutes.

[0120] Figure 5 is the acidity test curve of DHP-DAPhen, Figure 6 is the ligand concentration extraction curve of DHP-DAPhen, Figure 7 The kinetic test curve of DHP-DAPhen shows that the optimal acidity of DHP-DAPhen is 0.5-1.0M, and the separation effect is good. Eu / Am The temperature is 150-230, and the equilibrium time is good, less than 10 minutes.

[0121] Figure 8 is the acidity test curve of AE-DAPhen, Fig. 9 is the ligand concentration extraction curve of AE-DAPhen, Fig.10 The kinetic test curve of AE-DAPhen shows that the best acidity for AE-DAPhen is 0.5-1.0M, and the separation effect is good.Eu / Am The temperature is 200-320, and the equilibrium time is good, less than 10 minutes.

[0122] Fig.11 is the acidity test curve of AEE-DAPhen, Fig.12 is the ligand concentration extraction curve of AEE-DAPhen, Fig.13 The kinetic test curve of AEE-DAPhen shows that the best acidity for AEE-DAPhen is 0.5-1.0M, and the separation effect is good. Eu / Am The temperature is 200-290, and the equilibrium time is good, less than 10 minutes.

[0123] In summary, the present invention starts with the design of ligand molecular structure, and develops four new DAPhen ligands by designing the structure of the ligand. The ligands not only ensure a high distribution ratio for Eu, but also the introduction of the water-soluble ligands also ensures efficient stripping of Am. The lanthanum-actinium separation factors SF of the four DAPhen ligands are Eu / Am The ligand has good water solubility and extraction kinetics, and equilibrium can be reached in 10 minutes. The present invention provides a new idea for in-depth understanding of lanthanum and actinium separation, and provides technical support for establishing an advanced spent nuclear fuel reprocessing system and efficiently utilizing minor actinide elements.

[0124] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A DAPhen ligand, characterized in that It has the structure shown in Formula I: In Formula I, R1 and R2 are independently The R1 and R2 Indicates the connection site.

2. The DAPhen ligand according to claim 1, characterized in that The DAPhen ligand has a structure shown in any one of formulas L-1 to L-4:

3. The method for preparing the DAPhen ligand according to claim 1 or 2, characterized in that: The following steps are involved: Mixing 2,9-dicarboxylic acid-1,10-phenanthroline, an organic solvent and an acidic substance for reflux reaction to obtain dimethyl 2,9-dicarboxylic acid-1,10-phenanthroline; The dimethyl 2,9-dicarboxy-1,10-phenanthroline, a substitution raw material and an organic solvent are mixed for a substitution reaction to obtain the DAPhen ligand; the substitution raw material includes one or more of 3-amino-1-propanol, 3-amino-1,2-propylene glycol, 2-(2-aminoethoxy)ethanol and 2-(2-(2-aminoethoxy)ethoxy)ethanol.

4. The preparation method according to claim 3, characterized in that: The temperature of the reflux reaction is 60-100° C., and the time is 6-12 hours.

5. The preparation method according to claim 3, characterized in that: The temperature of the substitution reaction is 60-80° C. and the time is 6-12 hours.

6. Use of the DAPhen ligand according to claim 1 or 2 in the separation of lanthanides and actinides.

7. A method for separating lanthanides and actinides from waste liquid, characterized in that: The following steps are involved: The waste liquid is mixed with an extractant for solvent extraction, wherein the extractant is the DAPhen ligand according to claim 1 or 2, and the waste liquid contains lanthanides and actinides.

8. The method according to claim 7, characterized in that The lanthanide elements include europium, and the actinide elements include americium.

9. The method according to claim 7, characterized in that: The acidity of the waste liquid is 0.01-4M.

10. The method according to claim 7, characterized in that The concentration of the DAPhen ligand in the system during the solvent extraction is 2.5-40 mM.

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