Method for preparing adsorption material for simultaneously extracting rubidium and cesium by utilizing soft / hard template co-assembly and application

Abstract

The invention discloses a method for preparing an adsorption material for simultaneously extracting rubidium and cesium by using soft / hard template co-assembly and application, and belongs to the technical field of adsorption material preparation. The invention aims to solve the problems that a traditional adsorbent is poor in selectivity to similar alkali metal ions, slow in mass transfer rate, insufficient in acid environment stability and lack of an adsorption material for specific recognition of rubidium and cesium ions. The method comprises the following steps: 1, preparing cesium-imprinted hierarchical-pore mesoporous silica; 2, Cs / Rb-HMS is prepared; according to the invention, a macroporous-mesoporous channel is constructed; wherein a large hole (PS template) provides a rapid mass transmission channel, and an ion diffusion path is remarkably shortened, so that target ions can rapidly reach adsorption sites in the material; mesopores (Pluronic F127 template) provide a huge specific surface area and load a large number of Cs < + > imprinting sites and Rb < + > imprinting polymer layers, so that high adsorption capacity to Cs < + > and Rb < + > is ensured.

Description

Technical Field

[0001] The present invention belongs to the technical field of adsorption material preparation, and in particular relates to a method and application of preparing a rubidium and cesium adsorption material by co-assembling a soft / hard template and extracting the same. Background Art

[0002] As key rare metals, rubidium and cesium share remarkable similarities in their physical and chemical properties. For example, both possess excellent electrical and thermal conductivity, exceptional flexibility, and remarkable ductility. This high degree of similarity allows them to be used interchangeably in numerous technological scenarios. Consequently, both rubidium and cesium, in their elemental form and in various compounds, have been extensively applied at the forefront of science and technology, including electronics, specialty glass, catalysts, energy, and medicine. Rubidium and cesium play an indispensable role in these areas.

[0003] The main methods currently used for rubidium and cesium extraction are precipitation, solvent extraction, and adsorption. The precipitation method uses chemical reagents (such as sodium ferrocyanide) to generate rubidium and cesium precipitates, but it has problems such as lengthy processes and poor stability. Although the solvent extraction method has good separation effects, the strong acidic extractant can cause equipment corrosion, and the volatilization of organic solvents produces a pungent odor, causing environmental pollution. In addition, the back extraction requires multiple stages of circulation and is costly. The adsorption method, relying on the selective capture ability of materials such as molecular sieves and composite adsorbents, has become the optimal solution for extracting rubidium and cesium from low-grade resources (such as salt lake brine and lithium mica leachate), while avoiding environmental pollution problems. However, there is currently a lack of adsorption materials that specifically recognize the two ions of rubidium and cesium. Summary of the Invention

[0004] The purpose of the present invention is to solve the problems of poor selectivity of traditional adsorbents for similar alkali metal ions, slow mass transfer rate, insufficient stability in acidic environments and lack of adsorption materials that specifically recognize rubidium and cesium ions, and to provide

[0005] A method and application of preparing a rubidium and cesium adsorption material by co-assembling a soft / hard template and extracting the same time.

[0006] The present invention relates to a selective adsorption material for simultaneously extracting rubidium and cesium from lepidolite leachate; specifically, it relates to a method for constructing a hierarchical mesoporous substrate by a double template method and combining ion imprinting technology to achieve the selective adsorption of Cs + and Rb + Selective and efficient adsorption.

[0007] A method for preparing and extracting rubidium and cesium adsorption materials by co-assembling soft / hard templates is specifically completed by the following steps:

[0008] 1. Preparation of Cesium Imprinted Hierarchical Mesoporous Silica:

[0009] ①. Prepare template solution:

[0010] Pluronic F127 and cesium chloride are added to a mixed solution of deionized water and anhydrous ethanol, followed by heating in a constant-temperature water bath and stirring for a period of time to obtain a transparent homogeneous micelle solution; monodisperse polystyrene microspheres are added to the transparent homogeneous micelle solution, and heating in a constant-temperature water bath and stirring for a period of time are continued before allowing the solution to cool to room temperature to obtain a template solution;

[0011] ②. Co-assembly induction:

[0012] Under stirring conditions, concentrated ammonia water is added to the template solution, stirred at 30° C. to 40° C. for a period of time, ethyl orthosilicate is added dropwise, stirred for a period of time after the addition is completed, and then N-(trimethoxysilylpropyl)ethylenediaminetriacetic acid sodium salt is added dropwise and stirred for a period of time to obtain a mixture;

[0013] ③. Silicon skeleton molding:

[0014] The mixture was stirred under vigorous stirring for a period of time. After the reaction was completed, the solid was collected by vacuum filtration, and the collected solid material was washed alternately with anhydrous ethanol and deionized water, and finally dried to obtain a Cs-HMS composite precursor;

[0015] ④. Template removal:

[0016] Ⅰ. Add the Cs-HMS composite precursor to acidic ethanol and reflux in an oil bath at 85°C for a period of time. After the reaction is completed, cool to room temperature, centrifuge, and collect the solid.

[0017] Ⅱ. Repeat the above step Ⅰ several times to remove Pluronic F127 to obtain product A;

[0018] III. Transfer product A into toluene and reflux in an oil bath at 85°C for a period of time. After the reaction is complete, cool to room temperature, centrifuge, and collect the solid;

[0019] IV. Repeat step III several times to remove the polystyrene microspheres to obtain product B;

[0020] ⑤. Wash the product B and vacuum dry it to obtain cesium imprinted hierarchical mesoporous silica;

[0021] 2. Preparation of Cs / Rb-HMS:

[0022] ①, nitrogen was introduced into the reactor to fully replace the air, and cesium imprinted hierarchical mesoporous silica was placed in anhydrous acetonitrile under nitrogen atmosphere, and magnetically stirred at room temperature for a period of time to obtain a Cs-HMS solution;

[0023] ②、Imprinting monomer mixing:

[0024] Rubidium chloride, dibenzo-18-crown-6, and acrylamide were added to the Cs-HMS solution under nitrogen protection, and magnetic stirring was performed at a constant temperature for a period of time while maintaining the pH value of the system at 7.0-7.5 to obtain a preassembled complex;

[0025] ③、Initiation of polymerization:

[0026] adding azobisisobutyronitrile to the preassembled complex, heating and shaking the mixture in a water bath shaker for a period of time, and adding anhydrous acetonitrile during the reaction to compensate for the volatilization loss of the anhydrous acetonitrile to obtain a reaction solution;

[0027] ④. Cool the reaction solution to room temperature and centrifuge to collect the solid matter; wash the collected solid matter and then immerse it in HNO3 solution and shake it for a period of time to remove Rb + Finally, it is washed with water until neutral and dried in vacuum to obtain Cs / Rb-HMS, which is the adsorption material for simultaneous extraction of rubidium and cesium.

[0028] Principle of the present invention:

[0029] The present invention solves the problems of slow adsorption rate and poor selectivity in the process of extracting rubidium and cesium by conventional adsorption method, and uses ion imprinting technology to make the material have Cs + and Rb + The imprinted cavity is used to realize the extraction of Cs in the lepidolite leachate. + and Rb + Selective extraction.

[0030] The technical solution adopted by the present invention is to use poloxamer (Pluronic F127) and PS microspheres as a synergistic template to form a through-hole macroporous-mesoporous hierarchical structure in the silicon skeleton, significantly increasing the specific surface area and providing multiple loading spaces for imprinting sites. First, Cs is chelated using N-(trimethoxysilylpropyl) ethylenediaminetriacetic acid sodium salt (TMS-EDTA). + As a template, after etching, the Cs + Matching holes. Then in the existing Cs + Based on the imprinted site, dibenzo-18-crown-6 (DB18C6) and acrylamide (AM) were used to interact with Rb + Use the template to perform surface imprinting polymerization again; elute Rb + After that, Cs + and Rb + The imprinted cavities form a multi-level pore structure, which accelerates mass transfer and reduces diffusion resistance; the mesoporous material provides a high specific surface area, accommodates a large number of imprinted sites, and improves the adsorption capacity.

[0031] Beneficial effects of the present invention:

[0032] 1. The present invention prepares a new type of adsorption material for extracting rubidium and cesium at the same time. The material is constructed on a porous material to absorb Cs + and Rb + specific recognition site for Cs + and Rb + Highly selective;

[0033] Second, the present invention constructs a macroporous-mesoporous channel; the macropores (PS template) provide a fast mass transfer channel, significantly shortening the ion diffusion path, allowing the target ions to quickly reach the adsorption sites inside the material; the mesopores (PluronicF127 template) provide a huge specific surface area, which can load a large amount of Cs + Imprinted sites and Rb + Imprinted polymer layer, ensuring the Cs + and Rb + Have high adsorption capacity;

[0034] 3. The eluent in the synthesis process of the present invention can be recycled and treated, and does not contain organic heavy metal sludge; the crown ether structure is stable and there are no toxic degradation by-products; the use of chemical reagents is reduced, energy consumption is lowered and the environmental burden is alleviated, and the concept of green development is implemented. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 The Cs / Rb-HMS prepared in Example 1 reacts with Cs in the presence of competitive metal ions. + and Rb + Adsorption selectivity;

[0036] Figure 2 is the relationship between the number of cycle desorption and the Cs + adsorption capacity of the Cs / Rb-HMS prepared in Example 1;

[0037] Figure 3 It is the relationship between the number of cyclic desorption times and the adsorption capacity of Cs / Rb-HMS prepared in Example 1 for Rb+. DETAILED DESCRIPTION

[0038] Specific embodiment 1: This embodiment is a method for preparing a rubidium and cesium adsorption material by co-assembling a soft / hard template and extracting the rubidium and cesium adsorption material simultaneously, which is specifically completed by the following steps:

[0039] 1. Preparation of Cesium Imprinted Hierarchical Mesoporous Silica:

[0040] ①. Prepare template solution:

[0041] Pluronic F127 and cesium chloride are added to a mixed solution of deionized water and anhydrous ethanol, followed by heating in a constant-temperature water bath and stirring for a period of time to obtain a transparent homogeneous micelle solution; monodisperse polystyrene microspheres are added to the transparent homogeneous micelle solution, and heating in a constant-temperature water bath and stirring for a period of time are continued before allowing the solution to cool to room temperature to obtain a template solution;

[0042] ②. Co-assembly induction:

[0043] Under stirring conditions, concentrated ammonia water is added to the template solution, stirred at 30° C. to 40° C. for a period of time, ethyl orthosilicate is added dropwise, stirred for a period of time after the addition is completed, and then N-(trimethoxysilylpropyl)ethylenediaminetriacetic acid sodium salt is added dropwise and stirred for a period of time to obtain a mixture;

[0044] ③. Silicon skeleton molding:

[0045] The mixture was stirred under vigorous stirring for a period of time. After the reaction was completed, the solid was collected by vacuum filtration, and the collected solid material was washed alternately with anhydrous ethanol and deionized water, and finally dried to obtain a Cs-HMS composite precursor;

[0046] ④. Template removal:

[0047] Ⅰ. Add the Cs-HMS composite precursor to acidic ethanol and reflux in an oil bath at 85°C for a period of time. After the reaction is completed, cool to room temperature, centrifuge, and collect the solid.

[0048] Ⅱ. Repeat the above step Ⅰ several times to remove Pluronic F127 to obtain product A;

[0049] III. Transfer product A into toluene, reflux in an oil bath at 85°C for a period of time, cool to room temperature after the reaction is complete, centrifuge, and collect the solid;

[0050] IV. Repeat step III several times to remove the polystyrene microspheres to obtain product B;

[0051] ⑤. Wash the product B and vacuum dry it to obtain cesium imprinted hierarchical mesoporous silica;

[0052] 2. Preparation of Cs / Rb-HMS:

[0053] ①, nitrogen was introduced into the reactor to fully replace the air, and cesium imprinted hierarchical mesoporous silica was placed in anhydrous acetonitrile under nitrogen atmosphere, and magnetically stirred at room temperature for a period of time to obtain a Cs-HMS solution;

[0054] ②、Imprinting monomer mixing:

[0055] Rubidium chloride, dibenzo-18-crown-6, and acrylamide were added to the Cs-HMS solution under nitrogen protection, and magnetic stirring was performed at a constant temperature for a period of time while maintaining the pH value of the system at 7.0-7.5 to obtain a preassembled complex;

[0056] ③、Initiation of polymerization:

[0057] adding azobisisobutyronitrile to the preassembled complex, heating and shaking the mixture in a water bath shaker for a period of time, and adding anhydrous acetonitrile during the reaction to compensate for the volatilization loss of the anhydrous acetonitrile to obtain a reaction solution;

[0058] ④. Cool the reaction solution to room temperature and centrifuge to collect the solid matter; wash the collected solid matter and then immerse it in HNO3 solution and shake it for a period of time to remove Rb + Finally, it is washed with water until neutral and dried in vacuum to obtain Cs / Rb-HMS, which is the adsorption material for simultaneous extraction of rubidium and cesium.

[0059] Specific embodiment 2: The difference between this embodiment and specific embodiment 1 is that: the mass volume ratio of the mixed solution of Pluronic F127, cesium chloride, monodisperse polystyrene microspheres and deionized water and anhydrous ethanol described in step 1① is (1g-1.5g): (10mg-30mg): (0.4g-0.8g): 300mL; the volume ratio of deionized water to anhydrous ethanol in the mixed solution of deionized water and anhydrous ethanol described in step 1① is (150-180): (120-150); in step 1, Pluronic F127 and cesium chloride are added to a mixed solution of deionized water and anhydrous ethanol, then heated in a constant-temperature water bath at 30°C to 40°C and 400 to 600 rpm with stirring for 5 to 7 hours to obtain a transparent homogeneous micellar solution. Monodisperse polystyrene microspheres are added to the transparent homogeneous micellar solution, and heating and stirring in a constant-temperature water bath at 30°C to 40°C and 400 to 600 rpm for 20 to 40 minutes are continued. The solution is then allowed to cool to room temperature to obtain a template solution. The monodisperse polystyrene microspheres described in step 1 (1) have a particle size of 400 nm. The remaining steps are the same as those in the first embodiment.

[0060] Specific embodiment 3: This embodiment differs from specific embodiment 1 or 2 in that: the mass fraction of the concentrated ammonia water described in step 1 (2) is 28%; the stirring speed described in step 1 (2) is 300 r / min to 500 r / min, and the stirring time is 10 min to 20 min; the dropwise addition rate described in step 1 (2) is 1 mL / min; the mass ratio of the concentrated ammonia water, ethyl orthosilicate, and sodium N-(trimethoxysilylpropyl)ethylenediaminetriacetic acid described in step 1 (2) to the cesium chloride described in step 1 (1) is (6 mL to 8 mL): (0.6 mL to 1 mL): (0.1 mL to 0.3 mL): (10 mg to 30 mg). The other steps are the same as specific embodiment 1 or 2.

[0061] Specific embodiment 4: This embodiment differs from specific embodiments 1 to 3 in that: in step 1 (3), the mixture is stirred at 800-1000 rpm for 3-5 hours. After the reaction, the solid is collected by vacuum filtration and washed alternately with anhydrous ethanol and deionized water, each washing 3-5 times. Finally, the collected solid is dried at 50-70°C for 2-3 hours to obtain a Cs-HMS composite precursor. The other steps are the same as those of specific embodiments 1 to 3.

[0062] Specific embodiment 5: This embodiment differs from specific embodiments 1 to 4 in that: the acidic ethanol in step 1 (IV) is an anhydrous ethanol solution containing 0.1 mol / L HCl; the oil bath reflux time at 85°C in steps 1 (IV) and 1 (III) is 24 to 96 hours; the centrifugation speed is 10,000 rpm, and the centrifugation time is 10 to 15 minutes; in steps 1 (IV) and 1 (IV), step I is repeated 2 to 4 times; in steps 1 (IV) and 1 (IV), step III is repeated 1 to 3 times; in step 1 (IV), product B is washed sequentially with deionized water and anhydrous ethanol, each washed 2 to 4 times, and then vacuum dried at 60 to 70°C for 10 to 12 hours. The other steps are the same as specific embodiments 1 to 4.

[0063] Specific Embodiment 6: This embodiment differs from Specific Embodiments 1 to 5 in that the volume ratio of the cesium-imprinted hierarchical mesoporous silica to anhydrous acetonitrile in step 2 (1) is 100 mg:(50 mL to 70 mL); the magnetic stirring speed in step 2 (1) is 500 rpm, and the magnetic stirring time is 20 to 40 minutes. The other steps are the same as Specific Embodiments 1 to 5.

[0064] Specific embodiment 7: This embodiment differs from specific embodiments 1 to 6 in that the mass volume ratio of the cesium imprinted hierarchical mesoporous silica described in step 2 ① to the rubidium chloride, dibenzo-18-crown-6, and acrylamide described in step 2 ② is 100 mg: (10 mg to 20 mg): (20 mL to 30 mL): (25 mL to 35 mL); the constant temperature magnetic stirring temperature described in step 2 ② is 40° C. to 50° C., the stirring speed is 500 rpm to 800 rpm, and the magnetic stirring time is 2 h to 4 h. The other steps are the same as specific embodiments 1 to 6.

[0065] Specific embodiment 8: This embodiment differs from specific embodiments 1 to 7 in that the volume ratio of the cesium-imprinted hierarchical mesoporous silica described in step 2 (1) to the azobisisobutyronitrile described in step 2 (3) and the additional anhydrous acetonitrile is 100 mg: (15 mg to 25 mg): (5 mL to 15 mL); the heating and shaking reaction described in step 2 (3) is carried out at a temperature of 50°C to 70°C, a speed of 200 rpm, and a reaction time of 20 h to 28 h. The other steps are the same as specific embodiments 1 to 7.

[0066] Specific embodiment nine: This embodiment differs from specific embodiments one to eight in that: the centrifugal speed described in step two (4) is 8000rpm~10000rpm, and the centrifugal time is 10min~20min; in step two (4), distilled water and anhydrous ethanol are used to alternately wash the collected solid matter, each washing 2 to 4 times; the concentration of the HNO3 solution described in step two (4) is 1mol / L; the mass of the collected solid matter described in step two (4) to the volume ratio of the HNO3 solution is (0.12g~0.15g):50mL; the time of the shock treatment described in step two (4) is 2h~3h; the temperature of the vacuum drying is 60℃~70℃, and the vacuum drying time is 10h~12h. The other steps are the same as specific embodiments one to eight.

[0067] Specific embodiment 10: This embodiment differs from specific embodiments 1 to 9 in that the rubidium and cesium adsorption material is used to simultaneously extract rubidium and cesium from the lepidolite leachate. The other steps are the same as those of specific embodiments 1 to 9.

[0068] The following examples are used to verify the beneficial effects of the present invention:

[0069] Example 1: A method for preparing a rubidium and cesium adsorption material by co-assembly of a soft / hard template and extracting the same is carried out in the following steps:

[0070] 1. Preparation of cesium imprinted hierarchical mesoporous silica (Cs-HMS):

[0071] ①. Prepare template solution:

[0072] 1.2 g of Pluronic F127 and 20 mg of cesium chloride were added to a mixed solution of 180 mL of deionized water and 120 mL of anhydrous ethanol, followed by mechanical stirring at 400 rpm in a constant temperature water bath at 35°C for 6 h to obtain a transparent homogeneous micellar solution. 0.6 g of monodisperse polystyrene microspheres were added to the transparent homogeneous micellar solution, and the mixture was further mechanically stirred at 400 rpm in a constant temperature water bath at 35°C for 30 min. The mixture was then allowed to cool to room temperature to obtain a template solution.

[0073] The particle size of the monodisperse polystyrene microspheres described in step 1① is 400 nm;

[0074] ②. Co-assembly induction:

[0075] Under stirring conditions, 7 mL of concentrated ammonia water was added to the template solution, and the mixture was stirred at 35° C. and 400 r / min for 10 min. 0.8 mL of tetraethyl orthosilicate (TEOS) was slowly added at a rate of 1 mL / min using a dropping funnel, and the stirring was continued for 15 min. 0.2 mL of sodium N-(trimethoxysilylpropyl)ethylenediaminetriacetic acid (TMS-EDTA) was then added dropwise at a dropwise rate of 1 mL / min. After the addition was completed, the mixture was stirred for 15 min to obtain a mixture.

[0076] The mass fraction of the concentrated ammonia water described in step 1② is 28%;

[0077] ③. Silicon skeleton molding:

[0078] The mixture was stirred at 800 rpm for 4 h. After the reaction, the solid was collected by vacuum filtration, and the collected solid was washed alternately with anhydrous ethanol and deionized water for 3 times each, and finally dried at 60°C for 2 h to obtain a Cs-HMS composite precursor.

[0079] ④. Template removal:

[0080] Ⅰ. Add the Cs-HMS composite precursor to 200 mL of acidic ethanol and reflux in an oil bath at 85°C for 24 h. Add 5 mL of deionized water every 24 h to compensate for evaporation loss. After the reaction is completed, cool to room temperature and centrifuge at 10,000 rpm for 10 min to collect the solid.

[0081] The acidic ethanol described in step 1④Ⅰ is an anhydrous ethanol solution containing 0.1 mol / L HCl;

[0082] Ⅱ. Repeat the above step Ⅰ 2 times to remove Pluronic F127 to obtain product A;

[0083] III. Transfer product A into toluene and reflux in an oil bath at 85°C for 24 h. Add 5 mL of deionized water to compensate for evaporation loss. After the reaction is complete, cool to room temperature and centrifuge at 10,000 rpm for 10 min to collect the solid.

[0084] IV. Repeat the above step III once to remove the polystyrene microspheres to obtain product B;

[0085] ⑤. Wash product B with deionized water and anhydrous ethanol three times each, and then vacuum dry at 60°C for 12 h to obtain cesium imprinted hierarchical mesoporous silica (Cs-HMS);

[0086] 2. Preparation of Cs / Rb-HMS:

[0087] ① Nitrogen was introduced into the reactor for 10 minutes to fully replace the air. 100 mg of cesium-imprinted hierarchical mesoporous silica was placed in 60 mL of anhydrous acetonitrile under a nitrogen atmosphere. The mixture was magnetically stirred at 500 rpm for 20 minutes at room temperature under nitrogen protection to obtain a Cs-HMS solution.

[0088] ②、Imprinting monomer mixing:

[0089] To the Cs-HMS solution, 15 mg of rubidium chloride (RbCl), 25 mL of dibenzo-18-crown-6, and 30 mL of acrylamide (AM) were added, and the mixture was stirred at 45°C and 500 rpm for 3 h, maintaining the pH value of the system at 7.0-7.5, to obtain a preassembled complex.

[0090] ③、Initiation of polymerization:

[0091] 20 mg of azobisisobutyronitrile (AIBN) was added to the preassembled complex, and the mixture was heated and shaken at 200 rpm in a water bath shaker at 60°C for 24 h. During the reaction, 10 mL of anhydrous acetonitrile was added to compensate for the volatilization loss of anhydrous acetonitrile to obtain a reaction solution;

[0092] ④ After cooling the reaction solution to room temperature, centrifuge it at 8000 rpm for 10 min to collect the solid matter; wash the collected solid matter alternately with distilled water and anhydrous ethanol, wash each for 3 times, and then immerse it in a 1 mol / L HNO3 solution and shake it for 2 h to remove Rb + Finally, it was washed with water until neutral, and dried under vacuum at 70 ° C for 12 h to obtain Cs / Rb-HMS, which is the adsorption material for simultaneous extraction of rubidium and cesium;

[0093] The volume ratio of the mass of the collected solid material described in step 2 (4) to the HNO3 solution is 0.12g:50mL.

[0094] Example 2: This example differs from Example 1 in that, in step 1 (IV) I, the Cs-HMS composite precursor was added to 200 mL of acidic ethanol and refluxed in an oil bath at 85°C for 36 h, with 5 mL of deionized water added every 24 h to compensate for evaporation losses. All other steps and parameters were the same as in Example 1.

[0095] Example 3: This example differs from Example 1 in that in step 1 (IV) I, the Cs-HMS composite precursor was added to 200 mL of acidic ethanol and refluxed in an oil bath at 85°C for 60 h, with 5 mL of deionized water added every 24 h to compensate for evaporation losses. All other steps and parameters were the same as in Example 1.

[0096] Example 4: This example differs from Example 1 in that in step 1 (IV) I, the Cs-HMS composite precursor was added to 200 mL of acidic ethanol and refluxed in an oil bath at 85°C for 72 h, with 5 mL of deionized water added every 24 h to compensate for evaporation losses. All other steps and parameters were the same as in Example 1.

[0097] Example 5: This example differs from Example 1 in that in step 1 (IV) I, the Cs-HMS composite precursor was added to 200 mL of acidic ethanol and refluxed in an oil bath at 85°C for 84 h, with 5 mL of deionized water added every 24 h to compensate for evaporation losses. All other steps and parameters were the same as in Example 1.

[0098] Example 6: This example differs from Example 1 in that in step 1 (IV) I, the Cs-HMS composite precursor was added to 200 mL of acidic ethanol and refluxed in an oil bath at 85°C for 96 h, with 5 mL of deionized water added every 24 h to compensate for evaporation losses. All other steps and parameters were the same as in Example 1.

[0099] In order to determine the effect of Cs / Rb-HMS on Cs + and Rb + The adsorption selectivity of Cs + , Rb + Mg 2+ , K + 、Na + He Li + The adsorption capacity on Cs / Rb-HMS was determined as follows: 0.5 g of Cs / Rb-HMS prepared in Example 1 was added to 100 mL of Cs + , Rb + Mg 2+ , K + 、Na + He Li + In the solution, Cs + , Rb + Mg 2+ , K +、Na + He Li + The concentration of each was 100 mg / L, and the adsorption was carried out at 27 °C and a stirring speed of 150 r / min. The adsorption amount was shown in Figure 1 As shown;

[0100] Figure 1 The Cs / Rb-HMS prepared in Example 1 reacts with Cs in the presence of competitive metal ions. + and Rb + Adsorption selectivity;

[0101] from Figure 1 It can be seen that the Cs / Rb-HMS prepared in Example 1 has a great influence on the Cs + and Rb + The adsorption capacity is much higher than that of the competing ion Mg 2 + 、Na + and K + In the presence of competing ions, Cs / Rb-HMS can effectively absorb Cs + The adsorption capacity of Rb + The adsorption capacity can still reach 49.6 mg / g; this shows that in the presence of Mg 2+ , K + 、Na + He Li + Under the interference of + and Rb + .

[0102] In order to determine the cyclic stability of Cs / Rb-HMS, 10 cyclic adsorption and desorption experiments were carried out to test its stability. The specific operation is as follows:

[0103] 0.5 g of Cs / Rb-HMS prepared in Example 1 was added to 100 mL of Cs + In the solution, Cs + The concentration of , was 100 mg / L, and the adsorption was carried out at 27 °C and a stirring speed of 150 r / min;

[0104] 0.5 g of Cs / Rb-HMS prepared in Example 1 was added to 100 mL of Rb + In the solution, Rb + The concentration of , was 100 mg / L, and the adsorption was carried out at 27 °C and a stirring speed of 150 r / min;

[0105] Figure 2 is the relationship between the number of cycle desorption and the Cs + adsorption capacity of the Cs / Rb-HMS prepared in Example 1;

[0106] Figure 3 It is the relationship between the number of cyclic desorption times and the adsorption capacity of Cs / Rb-HMS prepared in Example 1 for Rb+.

[0107] from Figures 2 and 3 It can be seen that: Cs / Rb-HMS has a great influence on the + and Rb + The adsorption capacity of the EDTA-CsO2 solution decreased slightly, but basically showed a stable trend. This is because the rigid base skeleton played a supporting and protective role, and the covalently bonded EDTA-CsO2 solution + The imprinted sites ensure the stability of adsorption. + The surface polymer imprinting layer of Cs / Rb-HMS also shows good stability thanks to the substrate protection. Therefore, Cs / Rb-HMS still maintains its chemical stability after 10 cycles of desorption, extending its service life. The experimental results show that even after 10 cycles of adsorption and desorption, the Cs / Rb-HMS still maintains its chemical stability and extends its service life. + The adsorption capacity did not decrease much (from 57.7 mg / g to 55 mg / g), and the adsorption capacity of Rb + The adsorption amount did not decrease much (from 49.6 mg / g to 45.3 mg / g).

Claims

1. A method for preparing a rubidium and cesium adsorption material by co-assembling a soft / hard template, characterized in that The method is specifically completed according to the following steps:

1. Preparation of Cesium Imprinted Hierarchical Mesoporous Silica: ①. Prepare template solution: Pluronic F127 and cesium chloride are added to a mixed solution of deionized water and anhydrous ethanol, followed by heating in a constant-temperature water bath and stirring for a period of time to obtain a transparent homogeneous micelle solution; monodisperse polystyrene microspheres are added to the transparent homogeneous micelle solution, and heating in a constant-temperature water bath and stirring for a period of time are continued before allowing the solution to cool to room temperature to obtain a template solution; ②. Co-assembly induction: Under stirring conditions, concentrated ammonia water is added to the template solution, stirred at 30° C. to 40° C. for a period of time, ethyl orthosilicate is added dropwise, stirred for a period of time after the addition is completed, and then N-(trimethoxysilylpropyl)ethylenediaminetriacetic acid sodium salt is added dropwise and stirred for a period of time to obtain a mixture; ③. Silicon skeleton molding: The mixture was stirred under vigorous stirring for a period of time. After the reaction was completed, the solid was collected by vacuum filtration, and the collected solid material was washed alternately with anhydrous ethanol and deionized water, and finally dried to obtain a Cs-HMS composite precursor; ④. Template removal: Ⅰ. Add the Cs-HMS composite precursor to acidic ethanol and reflux in an oil bath at 85°C for a period of time. After the reaction is completed, cool to room temperature, centrifuge, and collect the solid. Ⅱ. Repeat the above step Ⅰ several times to remove Pluronic F127 to obtain product A; III. Transfer product A into toluene, reflux in an oil bath at 85°C for a period of time, cool to room temperature after the reaction is complete, centrifuge, and collect the solid; IV. Repeat step III several times to remove the polystyrene microspheres to obtain product B; ⑤. Wash the product B and vacuum dry it to obtain cesium imprinted hierarchical mesoporous silica; 2. Preparation of Cs / Rb-HMS: ①, nitrogen was introduced into the reactor to fully replace the air, and cesium imprinted hierarchical mesoporous silica was placed in anhydrous acetonitrile under nitrogen atmosphere, and magnetically stirred at room temperature for a period of time to obtain a Cs-HMS solution; ②、Imprinting monomer mixing: Rubidium chloride, dibenzo-18-crown-6, and acrylamide were added to the Cs-HMS solution under nitrogen protection, and magnetic stirring was performed at a constant temperature for a period of time while maintaining the pH value of the system at 7.0-7.5 to obtain a preassembled complex; ③、Initiation of polymerization: adding azobisisobutyronitrile to the preassembled complex, heating and shaking the mixture in a water bath shaker for a period of time, and adding anhydrous acetonitrile during the reaction to compensate for the volatilization loss of the anhydrous acetonitrile to obtain a reaction solution; ④. Cool the reaction solution to room temperature and centrifuge to collect the solid matter; wash the collected solid matter and then immerse it in HNO3 solution and shake it for a period of time to remove Rb + Finally, it is washed with water until neutral and dried in vacuum to obtain Cs / Rb-HMS, which is the adsorption material for simultaneous extraction of rubidium and cesium.

2. The method for preparing and extracting rubidium and cesium adsorption materials by co-assembling soft / hard templates according to claim 1, characterized in that The mass volume ratio of the Pluronic F127, cesium chloride, monodisperse polystyrene microspheres and the mixed solution of deionized water and anhydrous ethanol described in step 1① is (1g~1.5g):(10mg~30mg):(0.4g~0.8g):300mL; the volume ratio of deionized water to anhydrous ethanol in the mixed solution of deionized water and anhydrous ethanol described in step 1① is (150~180):(120~150); Pluronic F127 and cesium chloride are added to the mixed solution of deionized water and anhydrous ethanol in step 1, and then heated in a constant temperature water bath at 30°C~40°C and 400r / min~600r / min and stirred for 5h~7h to obtain a transparent homogeneous micellar solution; Monodisperse polystyrene microspheres were added to the transparent homogeneous micelle solution, and the mixture was heated and stirred in a constant temperature water bath at 30°C to 40°C and 400 rpm to 600 rpm for 20 min to 40 min, and then allowed to stand and cool to room temperature to obtain a template solution; the particle size of the monodisperse polystyrene microspheres described in step 1① was 400 nm.

3. The method for preparing and extracting rubidium and cesium adsorption materials by co-assembling soft / hard templates according to claim 1, characterized in that The mass fraction of the concentrated ammonia water described in step 1 ② is 28%; the stirring speed described in step 1 ② is 300r / min~500r / min, and the stirring time is 10min~20min; the dropping speed described in step 1 ② is 1mL / min; the mass ratio of the concentrated ammonia water, ethyl orthosilicate, N-(trimethoxysilylpropyl)ethylenediaminetriacetic acid sodium salt described in step 1 ② and the cesium chloride described in step 1 ① is (6mL~8mL):(0.6mL~1mL):(0.1mL~0.3mL):(10mg~30mg).

4. The method for preparing and extracting rubidium and cesium adsorption materials by co-assembling soft / hard templates according to claim 1, characterized in that In step 1③, the mixture is stirred at 800 rpm to 1000 rpm for 3 h to 5 h. After the reaction is completed, the solid is collected by vacuum filtration, and the collected solid material is washed alternately with anhydrous ethanol and deionized water, each washing 3 to 5 times, and finally dried at 50 ° C to 70 ° C for 2 h to 3 h to obtain a Cs-HMS composite precursor.

5. The method for preparing and extracting rubidium and cesium adsorption materials by co-assembling soft / hard templates according to claim 1, characterized in that The acidic ethanol described in step 1④Ⅰ is an anhydrous ethanol solution containing 0.1 mol / L HCl; the oil bath reflux time at 85°C in steps 1④Ⅰ and Ⅲ is 24h~96h; the centrifugal speed is 10000r / min, and the centrifugation time is 10min~15min; in step 1④Ⅱ, the above step I is repeated 2~4 times; in step 1④Ⅳ, the above step III is repeated 1~3 times; in step 1⑤, the product B is washed with deionized water and anhydrous ethanol in sequence, each washed 2~4 times, and then vacuum dried at 60℃~70℃ for 10h~12h.

6. The method for preparing and extracting rubidium and cesium adsorption materials by co-assembling soft / hard templates according to claim 1, characterized in that The volume ratio of the cesium imprinted hierarchical mesoporous silica described in step 2① to anhydrous acetonitrile is 100 mg: (50 mL to 70 mL); the speed of the magnetic stirring described in step 2① is 500 rpm, and the magnetic stirring time is 20 min to 40 min.

7. The method for preparing and extracting rubidium and cesium adsorption materials by co-assembling soft / hard templates according to claim 1, characterized in that The mass volume ratio of the cesium imprinted hierarchical mesoporous silica described in step 2① to the rubidium chloride, dibenzo-18-crown-6, and acrylamide described in step 2② is 100 mg: (10 mg to 20 mg): (20 mL to 30 mL): (25 mL to 35 mL); the constant temperature magnetic stirring temperature described in step 2② is 40°C to 50°C, the stirring speed is 500 rpm to 800 rpm, and the magnetic stirring time is 2h to 4h.

8. The method for preparing and extracting rubidium and cesium adsorption materials by co-assembling soft / hard templates according to claim 1, characterized in that The volume ratio of the cesium imprinted hierarchical mesoporous silica described in step 2① to the azobisisobutyronitrile described in step 2③ and the added anhydrous acetonitrile is 100 mg: (15 mg ~ 25 mg): (5 mL ~ 15 mL); the temperature of the heating oscillation reaction described in step 2③ is 50 ° C ~ 70 ° C, the speed is 200 rpm, and the reaction time is 20h ~ 28h.

9. The method for preparing and extracting rubidium and cesium adsorption materials by co-assembling soft / hard templates according to claim 1, characterized in that The centrifugal speed described in step 2④ is 8000rpm~10000rpm, and the centrifugation time is 10min~20min; the collected solid material is washed alternately with distilled water and anhydrous ethanol in step 2④, each washing 2 to 4 times; the concentration of the HNO3 solution described in step 2④ is 1mol / L; the mass ratio of the collected solid material described in step 2④ to the volume ratio of the HNO3 solution is (0.12g~0.15g):50mL; the shaking treatment time described in step 2④ is 2h~3h; the vacuum drying temperature is 60℃~70℃, and the vacuum drying time is 10h~12h.

10. Use of the rubidium and cesium adsorption material prepared by the method of claim 1, characterized in that The simultaneous extraction of rubidium and cesium adsorption materials is used for the simultaneous extraction of rubidium and cesium from lepidolite leachate.

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