阅读说明：本技术 一种稀土钇离子水相印迹膜及其对相邻重稀土的分离应用 (Rare earth yttrium ion water-phase imprinted membrane and separation application thereof to adjacent heavy rare earth ) 是由 陈厉 汪怡锬 戴静闻 董欢 潘为国 于 2021-08-05 设计创作，主要内容包括：本发明公开了一种稀土钇离子水相印迹膜及其对相邻重稀土的分离应用,属于材料制备和分离技术领域。以聚偏氟乙烯、乙烯-乙烯醇共聚物和二(2,4,4-三甲基戊基)次磷酸共混制备聚合物杂化膜作为基膜。以Y离子为印迹模板离子,在纯水相介质中,以衣康酸IA为印迹功能单体,以N,N-亚甲基双丙烯酰胺MBA为交联剂,亚硫酸氢钠SBS过硫酸铵APS为氧化还原引发剂,在基膜表面印迹聚合,构筑钇离子水相印迹膜。该发明改善了稀土分离膜的亲水性,提高了对重稀土钬、钇、铒间的分离系数。制备过程纯水相介质中进行,膜材料的水接触角大幅降低。同时对印迹模板钇离子优先吸附与渗透,在同类稀土分离膜材料中具有极大优势。(The invention discloses a rare earth yttrium ion water-phase imprinted membrane and separation application thereof to adjacent heavy rare earth, belonging to the technical field of material preparation and separation. Polyvinylidene fluoride, ethylene-vinyl alcohol copolymer and di (2,4, 4-trimethyl amyl) hypophosphorous acid are blended to prepare a polymer hybrid membrane as a base membrane. Taking Y ions as imprinting template ions, taking itaconic acid IA as an imprinting functional monomer, taking N, N-methylene bisacrylamide MBA as a cross-linking agent and taking sodium bisulfite SBS ammonium persulfate APS as a redox initiator in a pure water phase medium, and carrying out imprinting polymerization on the surface of a base membrane to construct an yttrium ion water phase imprinting membrane. The invention improves the hydrophilicity of the rare earth separation membrane and improves the separation coefficient among the heavy rare earth holmium, yttrium and erbium. The preparation process is carried out in a pure water phase medium, and the water contact angle of the membrane material is greatly reduced. Meanwhile, the adsorption and permeation of the imprinting template yttrium ions are preferentially carried out, and the method has great advantages in the similar rare earth separation membrane materials.)

1. The preparation method of the rare earth yttrium ion water phase imprinting separation membrane is characterized by comprising the following steps of:

(1) preparation of polymer hybrid base membrane:

adding polyvinylidene fluoride (PVDF), ethylene-vinyl alcohol copolymer (EVOH) and di (2,4, 4-trimethylpentyl) hypophosphorous acid (Cyanex272) into N, N' -dimethylacetamide (DMAc) serving as a solvent, mixing, heating and stirring, and defoaming in vacuum for 30min after all the components are completely dissolved to form a uniform mixed solution to obtain a casting solution; slowly dripping the casting solution on a smooth glass plate, immersing the glass plate in a water bath for soaking after natural volatilization, taking out the film, and drying at room temperature to obtain the polymer hybrid base film;

(2) preparation of yttrium ion water-phase imprinted membrane:

mixing the base film obtained in the step (1) with yttrium chloride (YCl)₃) Mixing with Itaconic Acid (IA) mixed water solution, stirring for 1h at 60 ℃ (continuously introducing nitrogen), adding N, N-Methylene Bisacrylamide (MBA) solution dissolved with proper amount of secondary distilled water in advance, Ammonium Persulfate (APS) and Sodium Bisulfite (SBS) mixed solution, heating and stirring under the protection of nitrogen, taking out the blotting membrane after the reaction is finished, eluting the membrane plate ions, and drying at room temperature for later use.

2. The method for preparing a rare earth yttrium ion water phase imprinting separation membrane according to claim 1, wherein the mass fraction ratio range of PVDF to Cyanex272 in the step (1) is (0.75-0.6): (0.25-0.4); the addition mass fraction of EVOH is 10%; solid-to-liquid ratio of membrane component to DMAc 1 g: 10 mL; the reaction condition of heating and stirring is magnetic stirring at 85 ℃ for 24 hours; the height of the spread film is 400 mu m, the natural volatilization time is 30s, and the water bath condition is that the glass plate is immersed in the secondary distilled water for 24h at room temperature, and the secondary distilled water is replaced for many times.

3. A rare earth yttrium ion according to claim 1The preparation method of the water phase imprinting separation membrane is characterized in that the mass of the basement membrane in the step (2) is 50mg, YCl₃The molar ratio of the compound to IA is 1: 3-1: 8, base film and said yttrium chloride YCl₃And the solid-liquid ratio of the mixed aqueous solution of IA, MBA, APS and SBS is kept between 1: 600g mL^-1(ii) a The mass of the MBA is 0.45g, the total mass of the APS and the SBS is 0.09g, and the mass ratio is 1: 2; the reaction condition of heating and stirring is that magnetic stirring is carried out for 3-5h at the temperature of 60 ℃, and nitrogen atmosphere is continuously introduced; the eluent is disodium ethylene diamine tetraacetate EDTA solution with the concentration of 0.2mol L^-1。

4. The use of a rare earth yttrium ion aqueous phase imprinted separation membrane of claims 1-3 in the adsorptive separation of adjacent heavy rare earths Ho, Y and Er to achieve efficient extraction and separation of Y from Ho and Er.

Technical Field

The invention belongs to the technical field of material preparation and separation, and relates to a water-phase imprinting method of rare earth yttrium ions and a yttrium ion imprinting separation membrane material prepared by the same. Compared with other current rare earth ion separation membranes, the rare earth ion separation membrane has excellent separation capacity and hydrophilicity.

Background

Yttrium Y is used as the heavy rare earth element with the most content in ionic rare earth ore in south China, and is widely applied to products such as fluorescent powder, laser generators, superconductors and the like. Yttrium possesses these fields of application not only because of its own electronic properties but also because of its purity level, and therefore its price increases significantly with increasing purity. Therefore, the technical method for efficiently and environmentally separating and purifying the yttrium has higher social and economic values.

The membrane separation method is a green separation method due to the characteristics of simple operation, low energy consumption, high-efficiency separation and the like. For separation of yttrium, liquid membrane methods have been widely used in past studies. Although the liquid membrane has a larger mass transfer interfacial area, the problems of liquid membrane stability and experimental amplification are difficult to improve. The non-liquid film, such as a polymer hybrid film, fixes the rare earth extractant carrier by entanglement of polymer chains, thereby having better stability. However, these previous studies have not achieved high adsorptive separation performance for the target rare earth because the separation coefficient for the particular rare earth under study is not high.

The ion imprinting technology is applied to a membrane separation method, and the prepared ion imprinting membrane has certain research progress in the aspect of rare earth separation by virtue of having specific recognition capability on template ions. However, a polymer hybrid membrane is used as a matrix membrane material, and a hydrophilic yttrium ion imprinting layer is constructed on the surface of the matrix membrane material, so that the separation work of yttrium ions and adjacent coexisting rare earth holmium Ho ions and erbium Er ions is achieved, which is reported so far.

Disclosure of Invention

Aiming at the efficient separation of adjacent heavy rare earth ions Ho, Y and Er, a polymer hybrid membrane is prepared by blending polyvinylidene fluoride (PVDF), ethylene-vinyl alcohol copolymer (EVOH) and bis (2,4, 4-trimethylpentyl) hypophosphorous acid Cyanex272 and is used as a base membrane. Taking Y ions as imprinting template ions, taking itaconic acid IA as an imprinting functional monomer, taking N, N-methylene bisacrylamide MBA as a cross-linking agent and taking sodium bisulfite SBS ammonium persulfate APS as a redox initiator in a pure water phase medium, and carrying out imprinting polymerization on the surface of a base membrane to construct an yttrium ion water phase imprinting membrane.

A rare earth yttrium ion water phase imprinting separation membrane, a snowflake imprinting polymer layer is generated on an internal pore channel, and the average pore diameter is reduced to 0.85 μm from 1.70 μm compared with that of a basement membrane; the formation of the water phase blotting layer improves the surface hydrophilicity of the blotting membrane, and compared with the basement membrane, the water contact angle is reduced from 63.7 degrees to 20.3 degrees; under the optimized static adsorption and dynamic permeation conditions, the yttrium ion water phase imprinted membrane has the equilibrium adsorption capacity (9.19mg g) to Y^-1) Higher than Ho (3.32mg g)^-1) With Er (4.24mg g)^-1) And the separation coefficient among Ho, Y and Er is improved by preferentially permeating Y, compared with a base film, the beta (Y/Ho) is improved from 1.27 to 1.66, and the beta (Y/Er) is improved from 0.88 to 1.36; compared with the non-imprinted membrane, beta (Y/Ho) is increased from 1.26 to 1.66, and beta (Y/Er) is increased from 0.94 to 1.36.

The preparation method of the rare earth yttrium ion water phase imprinting separation membrane provided by the invention comprises the following steps:

(1) preparation of polymer hybrid base membrane:

adding polyvinylidene fluoride (PVDF), ethylene-vinyl alcohol copolymer (EVOH) and di (2,4, 4-trimethylpentyl) hypophosphorous acid (Cyanex272) into N, N' -dimethylacetamide (DMAc) serving as a solvent, mixing, heating and stirring, and defoaming in vacuum for 30min after all the components are completely dissolved to form a uniform mixed solution to obtain a casting solution; and slowly dripping the casting solution on a smooth glass plate, immersing the glass plate in a water bath for soaking after natural volatilization, taking out the film, and drying at room temperature to obtain the polymer hybrid base film.

Wherein, the mass fraction ratio range of PVDF and Cyanex272 is (0.75-0.6): (0.25-0.4); the addition mass fraction of EVOH is 10%; solid-to-liquid ratio of membrane component to DMAc 1 g: 10 mL; the reaction condition of heating and stirring is magnetic stirring at 85 ℃ for 24 hours. The height of the spread film is 400 mu m, the natural volatilization time is 30s, and the water bath condition is that the glass plate is immersed in the secondary distilled water for 24h at room temperature, and the secondary distilled water is replaced for many times.

(2) Preparation of yttrium ion water-phase imprinted membrane:

mixing the base film obtained in the step (1) with yttrium chloride (YCl)₃) Mixing with Itaconic Acid (IA) mixed water solution, stirring for 1h at 60 ℃ (continuously introducing nitrogen), adding N, N-Methylene Bisacrylamide (MBA) solution dissolved with proper amount of secondary distilled water in advance, Ammonium Persulfate (APS) and Sodium Bisulfite (SBS) mixed solution, heating and stirring under the protection of nitrogen, taking out the blotting membrane after the reaction is finished, eluting the membrane plate ions, and drying at room temperature for later use.

Wherein the mass of the basement membrane is 50mg, YCl₃The molar ratio of the compound to IA is 1: 3-1: 8, base film and said yttrium chloride YCl₃And the solid-liquid ratio of the mixed aqueous solution of IA, MBA, APS and SBS is kept between 1: 600g mL^-1(ii) a The mass of the MBA is 0.45g, the total mass of the APS and the SBS is 0.09g, and the mass ratio is 1: 2; the reaction conditions of heating and stirring are that magnetic stirring is carried out for 3-5h at the temperature of 60 ℃, and nitrogen atmosphere is continuously introduced. The eluent is disodium ethylene diamine tetraacetate EDTA solution with the concentration of 0.2mol L^-1。

(3) Preparation of non-blotting membranes:

the same preparation steps as step (2) except that YCl is not added₃And (4) preparing a non-imprinted membrane outside the aqueous solution.

The invention also provides application of the rare earth yttrium ion water-phase imprinting separation membrane in adsorption separation of adjacent heavy rare earths Ho, Y and Er, and realizes efficient extraction and separation of Y from Ho and Er.

Compared with the prior art, the invention has the beneficial effects that:

(1) in the invention, the polymer hybrid basement membrane and the imprinted polymer system are subjected to surface imprinting in a pure water medium, so that the appearance of the surface and the internal pore canal of the basement membrane is changed, and the surface hydrophilicity of the separation membrane is improved. The water phase blotting membrane has small hole diameter and big hole structure in thumb shape on the lower surface. After the imprinting and non-imprinting treatment, the membrane surface is covered with an imprinting polymerization layer. Under a scanning electron microscope, the imprinted polymer particles on the surface of the imprinted membrane are relatively dense, the average pore diameter is reduced from 1.70 mu m (basal membrane) to 0.85 mu m (imprinted membrane), and the average pore diameter of the non-imprinted membrane is 2.66 mu m. Meanwhile, the water contact angle was reduced from 63.7 ° to 20.3 ° compared to the base film.

(2) In the invention, the affinity of the blotting membrane to aqueous template ions Y is obviously improved in an aqueous imprinting polymerization mode, so that the Y ion aqueous blotting membrane preferentially adsorbs and separates Y ions. Under the optimized static adsorption and dynamic permeation conditions, the yttrium ion water phase imprinted membrane has the equilibrium adsorption capacity (9.19mg g) to Y^-1) Higher than Ho (3.32mg g)^-1) With Er (4.24mg g)^-1) And preferentially permeate Y; compared with the base film, the beta (Y/Ho) is increased from 1.27 to 1.66, and the beta (Y/Er) is increased from 0.88 to 1.36; compared with the non-imprinted membrane, beta (Y/Ho) is increased from 1.26 to 1.66, and beta (Y/Er) is increased from 0.94 to 1.36.

Drawings

FIG. 1 shows SEM pictures of different magnifications of the surfaces of a polymer hybrid base film (a 1: x 2000; a 2: x6500), a non-imprinted film (b 1: x 2000; b 2: x6500) and a yttrium ion water phase imprinted film (c 1: x 2000; c 2: x 6500).

FIG. 2 is a scanning electron micrograph of a cross section of a polymer hybrid base film (e1) and a yttrium ion water phase imprinted film (e 2).

FIG. 3 is a graph of the change in water contact angle of polymer hybrid base membranes of different compositions with yttrium ion water imprinted membranes (PIM-1: 25 wt.% Cyanex272-75 wt.% PVDF; PIM-2: 40 wt.% Cyanex272-60 wt.% PVDF; PIMs: 40 wt.% Cyanex272-50 wt.% PVDF-10 wt.% EVOH).

FIG. 4 is a graph showing the change of the adsorption capacity in static equilibrium of yttrium ion water-phase imprinted membranes prepared at different molar ratios of IA to Y.

FIG. 5 is a graph showing the change of the adsorption capacity in static equilibrium of yttrium ion water-phase imprinted membranes prepared under different polymerization reaction times.

FIG. 6 is a graph showing the dynamic osmotic concentration of Y versus time for the aqueous imprinted membrane and the non-imprinted membrane of yttrium ion.

Detailed Description

The invention will be further described with reference to the following figures and specific examples, but the scope of the invention is not limited thereto.

In the embodiment of the invention, the relevant adsorption separation performance of the yttrium ion water-phase imprinted membrane is inspected by adopting the following method, and the specific method comprises the following steps:

determination of the static adsorption amount of the membrane: accurately transferring standard solutions of yttrium chloride, holmium chloride and erbium chloride (from chemical reagents of national medicine group, Ltd.) to obtain a solution of 20 mg.L^-1And (3) adjusting the pH value of the standard solution to 4, accurately weighing 5mg of the yttrium ion water-phase imprinted membrane, adding the yttrium ion water-phase imprinted membrane into the solution, standing the solution in a constant-temperature water bath at 25 ℃ for 24 hours, and measuring the concentration of the residual rare earth in the solution by using an ultraviolet spectrophotometer. The volume of the solution was recorded as V (unit L), the mass of the polymer hybrid microporous membrane was recorded as m (unit g), and the initial concentration of the prepared solution was recorded as c₀(unit mg. L)^-1) (ii) a After the adsorption is finished, the residual rare earth concentration in the solution is c₁(unit mg. L)^-1) Then the equilibrium adsorption quantity Q of the film_e(unit mg. g)^-1) Comprises the following steps: q_e＝(c₀-c₁)*V/m。

Determination of the permeability coefficient, initial membrane flux and separation coefficient of the membrane dynamic permeation process: placing a piece of membrane with diameter of 1.5cm in a dynamic permeation H-shaped tube, and adding 100 mg.L to both sides^-1And carrying out dynamic transmission research on the yttrium chloride rare earth solution and hydrochloric acid stripping solution. And sampling from the feed liquid tanks at two sides at regular intervals to analyze the rare earth solubility. Permeability rate constant k(s)^-1) Permeability coefficient P (m.s)^-1) Initial membrane flux J_i(mol·m^-2·s^-1) And the separation coefficient β are calculated as follows:

k(s^-1)：ln(c/c_i)＝-kt

wherein, c_i(mol·L^-1) And c (mol. L)^-1) The concentrations of rare earth ions at the initial and different permeation times respectively; t(s) is the permeation time.

P(m·s^-1)：P＝(V/A)k

Wherein，V(m³) The volume of solution on the feed liquid side; a (m)²) K(s) is the effective contact area of the film^-1) Is the permeation rate constant.

J_i(mol·m^-2·s^-1)：J_i＝Pc_i

Wherein, c_i(mol·L^-1) Is the initial soil ion concentration, P (m.s)^-1) Is the permeability coefficient.

β：β＝J_i,RE1/J_i,RE2. Wherein, J_i,RE1And J_i,RE1The initial membrane fluxes of two different rare earth ions, respectively.

Example 1:

(1) preparation of polymer hybrid base membrane:

0.5g of PVDF powder, 0.1g of EVOH pellets and 0.4g of Cyanex272 were weighed out and dissolved in 10ml of DMAc at 85 ℃ for 24 hours under continuous stirring to obtain a homogeneous mixed solution. The casting solution was subjected to vacuum defoaming for 30 minutes to remove visible bubbles. The casting solution is coated on a smooth glass plate by a wet film coater with the height of 400 mu m to obtain a new liquid film. After natural volatilization for 30s, the glass plate was immersed in redistilled water for 12 hours, and the coagulation bath was changed 3 times. And drying at room temperature for 24 hours to obtain the polymer hybrid membrane.

(2) Preparation of yttrium ion water-phase imprinted membrane

Weighing 50mg and 20mL YCl of the basement membrane in the step (1)₃The aqueous solution (amount of yttrium ion-containing substance 1mmol) and IA (6mmol) were mixed and stirred at 60 ℃ for 1h (continuous nitrogen flow). Then 0.45g of MBA (solution prepared by mixing with 5ml of water) was added and nitrogen was introduced for 10min, and finally APS and SBS (mixed solution prepared by dissolving 0.09g of total mass in 5ml of water at a mass ratio of 1: 2) were added and nitrogen was continuously introduced for 3 h. The membrane after the reaction was taken out, washed with water, and then washed with 0.2mol L^-1And eluting the EDTA solution for 24 hours to obtain the yttrium ion water phase imprinted membrane, and drying at room temperature for later use.

(3) Preparation of non-blotting membranes

The same preparation steps as step (2) except that YCl is not added₃And (4) preparing a non-imprinted membrane outside the aqueous solution.

FIG. 1 shows scanning electron micrographs of different magnifications of the surfaces of a polymer hybrid base film (a 1: x 2000; a 2: x6500), a non-imprinted film (b 1: x 2000; b 2: x6500) and a yttrium ion water phase imprinted film (c 1: x 2000; c 2: x 6500). As can be seen from the figure, the yttrium ion water phase imprinted membrane prepared in this example has changed the pore morphology on the surface of the base membrane compared with the base membrane, the surface of the yttrium ion water phase imprinted membrane is covered with a uniform imprinted polymer layer, the imprinted polymer particles are dense and snowflake-shaped, the average pore diameter is reduced from 1.70 μm (base membrane) to 0.85 μm (imprinted membrane), and the average pore diameter of the non-imprinted membrane is 2.66 μm.

FIG. 2 shows the scanning electron micrograph of the cross section of the polymer hybrid base film (e1) and the yttrium ion water phase imprinted film (e 2). As can be seen from the figure, the yttrium ion water phase imprinted membrane prepared in the example has an asymmetric upper and lower surface structure compared with the base membrane. The diameter of the hole on the upper surface is small, and the lower surface is of a thumb-like large hole structure. After the imprinting treatment, the surface and the internal pore channels of the membrane are obviously reduced, and obvious snowflake-shaped imprinted polymer particles are also arranged on the internal pore channels.

TABLE 1 permeability coefficient P (μms) of polymer hybrid base membrane, yttrium ion water phase imprinted membrane and non-imprinted membrane to Ho, Y and Er^-1) Initial membrane flux J_i(μmol m^-2s^-1) And a list of separation coefficients.

Example 2:

in this example, when a polymer hybrid base membrane is prepared, mass fractions of PVDF, EVOH and Cyanex272 are adjusted to investigate changes in hydrophilicity of different base membranes, and determine an optimal composition of the base membrane of the yttrium ion water-phase imprinted membrane. The preparation methods of the polymer hybrid membrane and the yttrium ion water-phase imprinted membrane in this example are basically the same as those in example 1, and the specific addition amounts of the raw materials are shown in table 2.

TABLE 2 raw material mass fraction listing of polymer hybrid base membranes

FIG. 3 is a graph showing the change of water contact angle between polymer hybrid base membranes with different compositions and yttrium ion water-phase imprinted membranes. As can be seen from the graph, the water contact angle (73.3 ℃) of PIM-2 is slightly lower than that (79.4 ℃) of PIM-1 when the content of Cyanex272 is increased; when the EVOH content was increased from 0 to 10 wt.%, the water contact angle of the PIMs decreased to 63.7 °. The lower water contact angle means that the film has better hydrophilic performance, and when the yttrium ion imprinting polymerization is carried out in a subsequent aqueous phase medium, the film has better affinity to template yttrium ions, aqueous phase functional monomers, cross-linking agents, initiators and the like, and can obtain better imprinting effect. Therefore, a polymer hybrid film added with 10 wt.% of EVOH and 10 wt.% of Cyanex 27240 wt is selected as the optimal base film composition of the yttrium ion water-phase imprinted film.

Example 3:

in this embodiment, the molar ratio of the functional monomer IA and the yttrium ion in the water phase imprinting process is adjusted to study the influence of different molar ratios on the static equilibrium adsorption capacity of the yttrium ion water phase imprinting film, so as to determine the optimal molar ratio in the imprinting process. The yttrium ion water-phase imprinted membrane of this example was prepared in substantially the same manner as in example 1, except that the amounts of the IA-added substances were 3mmol, 4mmol, 5mmol, 7mmol, and 8mmol, respectively.

FIG. 4 shows the change of static equilibrium adsorption amount of Ho, Y and Er of yttrium ion water-phase imprinted films prepared under different IA/RE molar ratios. From the figure, it can be found that with the continuous increase of the functional monomer IA, the adsorption capacity of the yttrium ion water phase imprinted membrane to Y ions is gradually increased and then decreased, and when the molar ratio is 6-7, the adsorption capacity of the yttrium ion water phase imprinted membrane to Y is the highest, while the change rule of Ho and Er is not obvious, but the adsorption capacity is lower than Y. This shows that the recognition capability of the yttrium ion water-phase imprinted membrane on Y is indeed enhanced by the imprinted polymerization process of Y as a template ion. When the IA content is too high (molar ratio 8), the decrease in Y adsorption may be that the adsorption sites on the membrane have reached saturation.

Example 4:

in this example, the polymerization time of the water phase imprinting process was adjusted to study the effect of the polymerization time on the static equilibrium adsorption capacity of the yttrium ion water phase imprinted membrane, so as to determine the optimal reaction time of the imprinting process. The preparation method of the yttrium ion water phase imprinted membrane in the embodiment is basically the same as that in the embodiment 1, except that the imprinting reaction time is 3.5h, 4h, 4.5h and 5h respectively.

FIG. 5 shows the change of static equilibrium adsorption amount of Ho, Y and Er of yttrium ion water-phase imprinted films prepared under different imprinting polymerization reaction times. From the figure, the adsorption capacity of the yttrium ion water-phase imprinted membrane to three rare earth ions is gradually reduced along with the continuous increase of the polymerization time, and the adsorption capacity of Ho and Er is lower than that of Y. This indicates that polymerization for an excessively long time is not favorable for the increase of the adsorption amount, and the possible reason is that the increase of the polymerization time causes the continuous increase of imprinted polymer particles on the membrane, resulting in the entrapment of part of the adsorption sites.

Example 5:

the preparation method of the yttrium ion water-phase imprinted membrane in this embodiment is the same as that in embodiment 1, and the change of the rare earth ion concentration in the feed liquid pool in the dynamic permeation process of the yttrium ion imprinted membrane and the non-imprinted membrane to Ho, Y and Er is studied.

FIG. 6 is a graph showing the change of the dynamic transport concentration of the yttrium ion water phase imprinted membrane and the non-imprinted membrane to Y with time. Within the first 3 hours of starting permeation, both membranes permeated Y, but the permeation rate of the imprinted membrane was significantly faster than that of the non-imprinted membrane, indicating that the imprinted membrane had a faster recognition ability for Y ions.

Calculating the dynamic permeation data of Ho, Y and Er to obtain the permeation coefficients P (mu m s) of the polymer hybrid basal membrane, the yttrium ion water phase imprinted membrane and the non imprinted membrane to Ho, Y and Er^-1) Initial membrane flux J_i(μmol m^-2s^-1) And the separation coefficient are shown in Table 1. As shown in Table 1, only the permeability coefficient P and the initial membrane flux J of the yttrium ion water phase imprinted membrane to Y ions_iIs larger than Ho and Er. The yttrium ion water phase imprinted membrane is proved to have higher osmotic selectivity to Y ions. The separation coefficients among Ho, Y and Er are improved, compared with the base film that beta (Y/Ho) is improved from 1.27 to 1.66, and beta (Y/Er) is improved from 0.88 to 1.36; compared with the non-imprinted membrane, beta (Y/Ho) is increased from 1.26 to 1.66, and beta (Y/Er) is increased from 0.94 to 1.36.