Preparation method and application of eutectic iodine adsorbent based on pillararene

Abstract

The invention discloses a preparation method of a pillararene-based eutectic iodine adsorbent, and particularly relates to the field of adsorbents. The method comprises the following steps: dissolving pillararene and a compound containing an electron withdrawing group in a first solvent to obtain a first mixed solution; and standing the first mixed solution at a preset temperature until a blocky crystal is separated out, thereby obtaining the charge transfer eutectic. By utilizing the advantages that electron-rich supramolecular macrocyclic pillararene is easy to generate charge transfer (CT) and has an intrinsic cavity, the pillararene and a compound containing an electron withdrawing group are subjected to CT action to generate an extrinsic pore channel, so that the removal efficiency of iodine is high; the chemical composition and the assembly structure of the eutectic are finely regulated and controlled by using a macrocyclic main body competition method, so that the adsorption efficiency is further improved.

Description

Technical Field

[0001] The present application relates to the field of adsorbents, and in particular to a preparation method and application of a eutectic iodine adsorbent based on pillar aromatics. Background Art

[0002] Radioactive iodine is the main pollutant in nuclear fission wastewater. It has extremely high activity and biological hazards, and it is urgent to develop functional materials that can efficiently remove iodine. The construction of supramolecular assemblies through non-covalent interactions has become the cornerstone of functional material development. Among these interactions, charge transfer (CT) interactions are particularly noteworthy. Through CT, highly ordered structures (eutectics) with unique electronic properties can be formed. At the same time, CT is critical in enhancing the iodine adsorption performance of adsorbents. Therefore, the regulation of CT performance is very important for improving iodine adsorption performance. Existing adsorption materials through CT include metal-organic framework (MOF) materials, porous silicon, covalent organic frameworks, etc. However, these materials still have problems such as harsh and complex preparation conditions, poor stability, and difficult to regulate iodine adsorption performance. For example, MOF materials can effectively adsorb iodine molecules due to their highly ordered pore structure and functionalized surface, but some MOF materials are prone to lose their pore structure in a humid environment, resulting in a decrease in adsorption performance. In addition, the synthesis cost of MOF materials is high, and large-scale application is limited. Porous silicon materials have a large specific surface area and rich pore structure, and can adsorb iodine through charge transfer. However, porous silicon materials are easily affected by the external environment, especially under humid conditions, which will reduce the adsorption performance. In addition, the preparation of high-quality porous silicon materials requires complex processing technology, which increases the cost. Therefore, existing adsorption materials cannot meet the application requirements of efficient iodine adsorption. Summary of the invention

[0003] The main purpose of the present application is to provide a preparation method and application of a eutectic iodine adsorbent based on pillar aromatics, aiming to solve the problem of poor adsorption performance of existing iodine adsorption materials.

[0004] To achieve the above-mentioned objectives, the present application provides a method for preparing a eutectic iodine adsorbent based on columnar aromatics, comprising: dissolving the columnar aromatics and a compound containing an electron-withdrawing group in a first solvent to obtain a first mixed solution; allowing the first mixed solution to stand at a preset temperature until block crystals are precipitated to obtain a charge transfer eutectic.

[0005] Optionally, the compound containing an electron-withdrawing group includes a benzene derivative, a pyridine compound or an imidazole compound; and the molar ratio of the pillar aromatic hydrocarbon to the compound containing an electron-withdrawing group is 0.5-5.

[0006] Optionally, the pillararene is pillarhexaarene, the concentration of the pillarhexaarene is 1-20 mM, and the compound containing an electron-withdrawing group is tetrafluoroterephthalonitrile.

[0007] Optionally, after obtaining the charge transfer eutectic, the following steps are also included: placing the charge transfer eutectic in a first solvent to obtain a second mixed solution; mixing the regulator and the first solvent to obtain a third mixed solution; adding the third mixed solution to the second mixed solution, and allowing the first mixed solution to stand at a preset temperature.

[0008] Optionally, the regulator is a pillar pentaarylene, or a mixture of a pillar pentaarylene and a compound containing an electron-withdrawing group; when the regulator is a mixture of a pillar pentaarylene and a compound containing an electron-withdrawing group, the molar ratio of the pillar pentaarylene to the charge transfer eutectic is 0.2-1, and the molar ratio of the compound containing the electron-withdrawing group to the charge transfer eutectic is 1-2; when the regulator is a pillar pentaarylene, the molar ratio of the regulator to the charge transfer eutectic is 1-2.

[0009] Optionally, after obtaining the first mixed solution, the method further includes the following steps: adding a second solvent to the first mixed solution.

[0010] Optionally, the first solvent is dichloromethane and the second solvent is n-hexane.

[0011] In addition, the present invention also provides a eutectic iodine adsorbent based on pillar aromatics, including a charge transfer eutectic, wherein the charge transfer eutectic is EtP6-TFTN a or EtP6-TFTN b The charge transfer eutectic was obtained by the above-mentioned preparation method of the pillararene-based eutectic iodine adsorbent.

[0012] EtP6-TFTN a 、EtP6-TFTN b All of them belong to the triclinic system, and their space groups are all P-1;

[0013] EtP6-TFTN a The unit cell parameters are: α=108.963(4)°, β=108.419(4)°, γ=105.431(4)°,

[0014] EtP6-TFTN b The unit cell parameters are: α=68.459(4)°, β=89.110(5)°, γ=66.900(4)°,

[0015] In addition, the present invention also provides an application of an adsorbent based on pillar aromatics in an iodine adsorption process.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The present invention discloses a eutectic iodine adsorbent based on pillar aromatics. The electron-rich supramolecular macrocyclic pillar aromatics are easy to undergo charge transfer (CT) and have the advantage of intrinsic cavities. The pillar aromatics and compounds containing electron-withdrawing groups react with CT to generate non-intrinsic channels, which have a high removal efficiency for iodine. The charge transfer eutectic of the present application is grown in a liquid phase, and its structure will not be affected by a humid environment, thereby not affecting the adsorption performance. The pillar aromatics and compounds containing electron-withdrawing groups are both common organic substances, and are less expensive than existing adsorption materials. The macrocyclic main body competition method is used to finely regulate the chemical composition and assembly structure of the eutectic, thereby further improving the adsorption efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The EtP6-TFTN obtained in Example 1 of the preparation method of the eutectic iodine adsorbent based on pillar aromatics in this application a Powder X-ray diffraction pattern of

[0019] Figure 2 The EtP6-TFTN obtained in Example 1 of the preparation method of the eutectic iodine adsorbent based on pillar aromatics in this application a EtP6-TFTN a Crystal structure diagram and stacking arrangement diagram of host-guest complex;

[0020] Figure 3 The EtP6-TFTN obtained in Example 1 of the preparation method of the eutectic iodine adsorbent based on pillar aromatics in this application a Changes in UV absorption spectrum after adding iodine into water;

[0021] Figure 4 A diagram showing the unit cell parameter transformation of a crystal at different times during a crystal transformation process in a method for preparing a eutectic iodine adsorbent based on pillar aromatics in the present application;

[0022] Figure 5 The EtP6-TFTN obtained in Example 2 of the preparation method of the eutectic iodine adsorbent based on pillar aromatics in this application b Powder X-ray diffraction pattern of

[0023] Figure 6 The EtP6-TFTN obtained in Example 2 of the preparation method of the eutectic iodine adsorbent based on pillar aromatics in this application b EtP6-TFTN a Crystal structure diagram and stacking arrangement diagram of host-guest complex;

[0024] Figure 7 The EtP6-TFTN obtained in Example 2 of the preparation method of the eutectic iodine adsorbent based on pillar aromatics in this application b Changes in UV absorption spectrum after adding iodine into water;

[0025] Figure 8 This is a diagram of the iodine removal efficiency of a eutectic iodine adsorbent in a method for preparing a eutectic iodine adsorbent based on pillar aromatics in the present application;

[0026] Fig. 9 This is a diagram of the unit cell parameter transitions of a crystal at different times during a crystal transformation process in a method for preparing a eutectic iodine adsorbent based on pillar aromatics in the present application.

[0027] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of this application clearer, the technical solutions in this application will be clearly and completely described below in conjunction with the drawings in this application. Obviously, the described embodiments are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0029] The first embodiment of the present invention provides a method for preparing a eutectic iodine adsorbent based on pillar aromatics, such as Figure 1 As shown, the specific steps include:

[0030] Step S1, dissolving the pillararene and the compound containing an electron-withdrawing group in a first solvent at a molar ratio of 0.5-5 to obtain a first mixed solution;

[0031] Wherein, the compound containing electron-withdrawing group includes benzene derivatives, pyridine compounds or imidazole compounds. Pillar aromatic hydrocarbon is pillar hexaaromatic hydrocarbon, exemplary, such as pillar hexaaromatic hydrocarbon can be ethoxy pillar hexaaromatic hydrocarbon (EtP6), and the concentration of EtP6 is 1-20mM. EtP6 is prepared in advance by existing methods, and the prepared EtP6 is recrystallized and vacuum dried to obtain pure EtP6 compound, and the recrystallization solvent includes but is not limited to chloroform or acetone. The compound containing electron-withdrawing group can be tetrafluoroterephthalonitrile (TFTN), and the first solvent can be dichloromethane.

[0032] The structural formula of EtP6 is as follows:

[0033]

[0034] The structural formula of TFTN:

[0035]

[0036] In order to prevent the solvent in the first mixed solution from volatilizing too quickly and affecting product performance, a second solvent is added to the first mixed solution after co-dissolution, wherein the second solvent can be n-hexane, and the ratio of the second solvent to the first solvent can be 2:1.

[0037] Step S2, standing the first mixed solution at a preset temperature for 3-5 days until yellow or orange block crystals are precipitated to obtain a charge transfer eutectic; wherein the preset temperature is room temperature, i.e., about 25° C.;

[0038] The reaction mechanism of the charge transfer co-crystal is as follows: EtP6 acts as a charge transfer π donor, TFTN is an electron-deficient π acceptor that easily generates charge transfer with the π donor, and the electron-rich ethoxy group in EtP6 easily generates charge transfer with the electron-deficient fluorine group and nitrile group in TFTN, thereby assembling together through supramolecular interactions. Among them, TFTN and EtP6 generate outer wall supramolecular interactions such as π-π stacking and CH···π interactions. b CH···F interactions also occur.

[0039] The second embodiment of the present invention provides a eutectic iodine adsorbent based on columnar aromatics, which is obtained by the above method. When the concentration of columnar aromatics and the molar ratio of columnar aromatics to the compound containing electron-withdrawing groups are different, the obtained products are also different. Specifically, when the concentration of EtP6 is 1-2mM and the molar ratio of EtP6 to TFTN is 0.5-5, the obtained charge transfer eutectic is EtP6-TFTN a When the concentration of EtP6 is 5-20 mM and the molar ratio of EtP6 to TFTN is 0.5-1, the eutectic iodine adsorbent based on pillararene is EtP6-TFTN. a When the molar ratio of EtP6 to TFTN is 2-5, the eutectic iodine adsorbent based on pillar aromatics is EtP6-TFTN b .

[0040] EtP6-TFTN a and EtP6-TFTN b All of them are two-dimensional layered supramolecular network structures, belonging to the triclinic system, and the space group is P-1;

[0041] EtP6-TFTN a The unit cell parameters are: α=108.963(4)°, β=108.419(4)°, γ=105.431(4)°,

[0042] EtP6-TFTN b The unit cell parameters are: α=68.459(4)°, β=89.110(5)°, γ=66.900(4)°, On the basis of the above-mentioned embodiment, the preparation method of the present invention further comprises a control method, that is, the charge transfer eutectic obtained in step 2 is controlled to make EtP6-TFTN b Convert to EtP6-TFTN a Or make EtP6-TFTN a Convert to EtP6-TFTN b , the specific control methods are as follows:

[0043] Step S3, placing the charge transfer eutectic in the first solvent to obtain a second mixed solution; mixing the regulator and the first solvent to obtain a third mixed solution; adding the third mixed solution to the second mixed solution, and standing the first mixed solution at a preset temperature for 2-4 hours to make EtP6-TFTN b Convert to EtP6-TFTN a , or make EtP6-TFTN a Convert to EtP6-TFTN b .

[0044] Among them, when the charge transfer eutectic is EtP6-TFTN a When the regulator is a mixture of ethoxylated pentaaromatic hydrocarbons and a compound containing an electron-withdrawing group, the molar ratio of ethoxylated pentaaromatic hydrocarbons to the charge transfer eutectic is 0.5-1, and the molar ratio of the compound containing an electron-withdrawing group to the charge transfer eutectic is 1-2. When the charge transfer eutectic is EtP6-TFTN b When the regulator is ethoxylated pentaaromatic hydrocarbon, the molar ratio of the regulator to the charge transfer eutectic is 1-2. The mechanism of the regulator is: EtP5 competes with EtP6 for TFTN to achieve EtP6-TFTN b Convert to EtP6-TFTN a , EtP5 achieves EtP6-TFTN by enriching TFTN a Convert to EtP6-TFTN b , thereby achieving fine control of the chemical composition of the eutectic iodine adsorbent.

[0045] The structural formula of EtP5 is as follows:

[0046]

[0047] Example 1

[0048] Weigh EtP6 and TFTN in a glass vial at a molar ratio of 1, dissolve the two in dichloromethane (EtP6 concentration is greater than 5mM / L) to obtain a first mixed solution, wait for the first mixed solution to change from clear to yellow, stir thoroughly, filter through a 0.22 micron organic filter membrane, add n-hexane, the volume of n-hexane is twice that of dichloromethane, loosen the bottle cap slightly, let stand at room temperature until the solvent evaporates slowly, and yellow or orange block eutectics will slowly precipitate; grind the obtained yellow block crystals into powder, place in a vacuum drying oven, and dry overnight at 50°C to obtain EtP6-TFTN a .

[0049] The EtP6-TFTN obtained in this example a The crystal structure was characterized by powder X-ray diffractometry. Figure 1 As shown, the diffraction peak signals of the prepared powder crystals all match the simulated XRD data, indicating the successful synthesis of the material.

[0050] The EtP6-TFTN obtained in this example a The crystal structure diagram and the stacking arrangement of the host-guest complex are shown in Figure 2 As shown in the figure, it shows that EtP6 has a supramolecular interaction with the two surrounding TFTN molecules (TFTN in the same crystallographic sense), and EtP6 also has a supramolecular interaction with the other four surrounding EtP6 molecules; along one axis: TFTN and EtP6 appear staggered to form a supramolecular network, which shows that EtP6-TFTN a The order and porosity of the cocrystal are conducive to the adsorption of iodine via the charge transfer effect.

[0051] Take 3 mg of the prepared EtP6-TFTN a Crush and mix 3 mg of EtP6-TFTN under normal pressure. a As an adsorbent, it was added to 3 mL of 0.8 mM iodine aqueous solution to conduct an iodine adsorption experiment, and the iodine adsorption process was monitored by UV-visible absorption spectroscopy. The results are as follows Figure 3 As shown, EtP6-TFTN was added a After that, the color of the iodine solution gradually changed from dark purple to colorless, indicating that EtP6-TFTN a Gradually absorbed the iodine in the solution. The aqueous solution of iodine has a clear I2 ultraviolet absorption peak at 460nm and a clear I3 - UV absorption peak, with the increase of adsorption time, the UV absorption intensity at 460nm gradually decreased until it disappeared. The absorption peak at 350nm first increased and then decreased with time until it disappeared. This shows that the addition of adsorbent promotes the dissociation of iodine in water and then adsorbs it.

[0052] Example 2

[0053] Based on Example 1, EtP6-TFTN a Place in dichloromethane solution to obtain a second mixed solution; mix EtP5, TFTN and dichloromethane solution to obtain a third mixed solution, EtP5 and EtP6-TFTN a The molar ratio of TFTN to EtP6-TFTNa is 1. After standing for 2 days, EtP6-TFTN can be obtained. b Crystal.

[0054] The unit cell parameters of the crystal at different times during the crystal transformation process of this embodiment are recorded, and the results are as follows: Figure 4 As shown, it was found that a small amount of EtP5 can promote EtP6-TFTN a Combined with TFTN to become EtP6-TFTN b Crystals; a large amount of EtP5 can promote EtP6-TFTN a Disassemble with TFTN to form EtP6-TFTN a Crystal.

[0055] Example 3

[0056] Weigh EtP6 and TFTN in a glass vial at a molar ratio of 2, dissolve the two in dichloromethane (EtP6 concentration is greater than 5mM / L) to obtain a first mixed solution, wait for the first mixed solution to change from clear to yellow, stir thoroughly, filter through a 0.22 micron organic filter membrane, add n-hexane, the volume of n-hexane is twice that of dichloromethane, loosen the bottle cap slightly, let stand at room temperature until the solvent evaporates slowly, and yellow or orange block eutectics will slowly precipitate; grind the obtained yellow block crystals into powder, place in a vacuum drying oven, and dry overnight at 50°C to obtain the charge transfer eutectic EtP6-TFTN b .

[0057] The charge transfer eutectic obtained in this example was characterized by powder X-ray diffractometer. The results are as follows: Figure 5 As shown in Figure 2, the diffraction peak signals of the prepared powder crystals all match the simulated XRD data, indicating that the obtained crystals are EtP6-TFTN b , EtP6-TFTN b The crystal structure diagram and the stacking arrangement of the host-guest complex are shown in Figure 6 As shown, it indicates that EtP6 has a supramolecular interaction with the two surrounding TFTN molecules (two TFTNs in the crystallographic sense), and EtP6 also has a supramolecular interaction with the other four surrounding EtP6s; looking along one axis: TFTN and EtP6 appear interlaced to form a supramolecular network.

[0058] Take 3 mg of the prepared EtP6-TFTN b Crush and mix 3 mg of EtP6-TFTN under normal pressure. b As an adsorbent, it was added to 3 mL of 0.8 mM iodine aqueous solution to conduct an iodine adsorption experiment, and the iodine adsorption process was monitored by UV-visible absorption spectroscopy. The results are as follows Figure 7 As shown, EtP6-TFTN was added b After that, the color of the iodine solution gradually changed from dark purple to colorless, indicating that EtP6-TFTN a Gradually absorbed the iodine in the solution. The aqueous solution of iodine has a clear I2 ultraviolet absorption peak at 460nm and a clear I3 - UV absorption peak, with the increase of adsorption time, the UV absorption intensity at 460nm gradually decreased until it disappeared. The absorption peak at 350nm first increased and then decreased with time until it disappeared. This shows that the addition of adsorbent promotes the dissociation of iodine in water and then adsorbs it.

[0059] According to the ultraviolet absorption intensity of iodine aqueous solution at 350nm and 460nm, the EtP6-TFTN a and EtP6-TFTN b The change of adsorption time, and the adsorption of I2 and I3 in aqueous solution by the adsorbent material were plotted. - The removal efficiency is as follows: Figure 8 EtP6-TFTN a With EtP6-TFTN b In water, for I2 and I 3- The removal efficiency of iodine adsorption was 99.04%, 91.13%, 98.87% and 88.21% respectively. It shows that it is a liquid iodine adsorption material with excellent performance. a For I2 and I3 in aqueous solution - The removal efficiency is better.

[0060] Example 4

[0061] On the basis of Example 3, the charge transfer eutectic was placed in a dichloromethane solution to obtain a second mixed solution; EtP5 and the dichloromethane solution were mixed to obtain a third mixed solution, the molar ratio of EtP5 to the charge transfer eutectic was 2, the third mixed solution was added to the second mixed solution, and the first mixed solution was allowed to stand at room temperature for 4 days to allow EtP6-TFTN b Convert to EtP6-TFTN a .

[0062] The unit cell parameters of the crystal at different times during the crystal transformation process of this embodiment are recorded, and the results are as follows: Fig. 9 As shown, EtP5 can promote EtP6-TFTN b Disassemble with TFTN to form EtP6-TFTN a crystals, and in the process, EtP6-TFTN was produced c and EtP6-TFTN d Two intermediate crystals. EtP6-TFTN c and EtP6-TFTN d All of them are two-dimensional layered supramolecular network structures, belonging to the triclinic system, and the space group is P-1; EtP6-TFTN c The unit cell parameters are: α=81.421(4)°, β=78.371(4)°, γ=87.608(5)°, EtP6-TFTN d The unit cell parameters are: α=75.269(7)°, β=81.803(7)°, γ=76.734(7)°,

[0063] Example 5

[0064] Weigh EtP6 and TFTN in a glass vial at a molar ratio of 0.5, dissolve the two in dichloromethane (EtP6 concentration is greater than 5mM / L) to obtain a first mixed solution, wait for the first mixed solution to change from clear to yellow, stir thoroughly, filter through a 0.22 micron organic filter membrane, add n-hexane, the volume of n-hexane is twice that of dichloromethane, loosen the bottle cap slightly, let stand at room temperature until the solvent evaporates slowly, and yellow or orange block eutectics will slowly precipitate; grind the obtained yellow block crystals into powder, place in a vacuum drying oven, and dry overnight at 50°C to obtain EtP6-TFTN a ;

[0065] EtP6-TFTN a Place in dichloromethane solution to obtain a second mixed solution; mix EtP5, TFTN and dichloromethane solution to obtain a third mixed solution, EtP5 and EtP6-TFTN a The molar ratio of TFTN to EtP6-TFTNa is 1. After standing for 2 days, EtP6-TFTN can be obtained. b Crystal.

[0066] Example 6

[0067] EtP6 and TFTN were weighed in a glass vial at a molar ratio of 3, and the two were co-dissolved in dichloromethane (EtP6 concentration was greater than 5mM / L) to obtain a first mixed solution. After the first mixed solution changed from clear to yellow and was fully stirred, it was filtered through a 0.22 micron organic filter membrane and then n-hexane was added. The volume of n-hexane was twice that of dichloromethane. The bottle cap was slightly loosened and allowed to stand at room temperature until the solvent evaporated slowly. Yellow or orange block eutectics would slowly precipitate. The obtained yellow block crystals were ground into powder, placed in a vacuum drying oven, and dried overnight at 50°C to obtain the charge transfer eutectic EtP6-TFTN. b .

[0068] On the basis of Example 3, the charge transfer eutectic was placed in a dichloromethane solution to obtain a second mixed solution; EtP5 and the dichloromethane solution were mixed to obtain a third mixed solution, the molar ratio of EtP5 to the charge transfer eutectic was 2, the third mixed solution was added to the second mixed solution, and the first mixed solution was allowed to stand at room temperature for 4-5 days to allow EtP6-TFTN b Convert to EtP6-TFTN a .

[0069] The present invention can be known by testing that when the concentration of EtP6 is between 1-2mM, if the molar ratio of EtP6 to TFTN is greater than 5 or less than 0.5, the excess raw material will precipitate in the form of colorless crystals; when the concentration of EtP6 is between 5-20mM, if the molar ratio of EtP6 to TFTN is greater than 5 or less than 0.5, the excess raw material will precipitate in the form of colorless crystals, and the collision between the excess raw materials in the liquid phase will not produce an assembly, thereby affecting the assembly efficiency. When the concentration of EtP6 is less than 1mM, the EtP6 and TFTN in the system are more difficult to combine, which will reduce the binding rate, and the crystallization is mostly colorless crystals, and it is difficult to grow colored charge transfer eutectics. When the concentration of EtP6 is greater than 20mM, the system will be closer to saturation, and precipitation will be quickly precipitated. The EtP6 and TFTN in the system will not have time to act, and the precipitation is mostly not crystals, and it is difficult to grow colored charge transfer eutectics.

[0070] If in EtP6-TFTN a Convert to EtP6-TFTN b During the process, the molar ratio of EtP5 added to the charge transfer co-crystal is greater than 1, which will make the regulator ineffective and the crystal will still be EtP6-TFTN a If the molar ratio of EtP5 added to the charge transfer eutectic is less than 0.5, the crystal conversion will be incomplete. b Convert to EtP6-TFTN aDuring the process, if the molar ratio of the added EtP5 to the charge transfer co-crystal is less than 1, the regulator will also fail, and the crystal will still be EtP6-TFTN b If the molar ratio of EtP5 to charge transfer co-crystal is greater than 2, the transformed crystals will adhere to EtP5, making separation difficult.

[0071] The third embodiment of the present invention provides an application of a eutectic adsorbent based on pillar aromatics in an iodine adsorption process. It can be seen from the above embodiments that the charge transfer eutectic of the present invention can be used to remove iodine from aqueous solution. In addition, it can also be used for the adsorption of iodine in solid phase and gas phase, such as removing iodine in mask, membrane, and steam adsorption separation.

[0072] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for preparing a eutectic iodine adsorbent based on pillar aromatics, characterized in that: include: Co-dissolving the pillararene and the compound containing an electron-withdrawing group in a first solvent to obtain a first mixed solution; The first mixed solution is allowed to stand at a preset temperature until block crystals are precipitated to obtain a charge transfer eutectic.

2. The method for preparing a eutectic iodine adsorbent based on pillar aromatics according to claim 1, characterized in that: After the block crystals are precipitated, the method further comprises the following steps: placing the charge transfer co-crystal in a first solvent to obtain a second mixed solution; Mixing the regulating agent and the first solvent to obtain a third mixed solution; The third mixed solution is added into the second mixed solution, and the first mixed solution is allowed to stand at a preset temperature.

3. The method for preparing a eutectic iodine adsorbent based on pillar aromatics according to claim 2, characterized in that: The compound containing electron-withdrawing groups includes benzene derivatives, pyridine compounds or imidazole compounds; the molar ratio of the pillar aromatic hydrocarbon to the compound containing electron-withdrawing groups is 0.5-5.

4. The method for preparing a eutectic iodine adsorbent based on pillar aromatics according to claim 3, characterized in that: The pillar aromatic hydrocarbon is pillar hexa aromatic hydrocarbon, the concentration of the pillar hexa aromatic hydrocarbon is 1-20 mM, and the compound containing an electron-withdrawing group is tetrafluoroterephthalonitrile.

5. The method for preparing a eutectic iodine adsorbent based on pillar aromatics according to claim 4, characterized in that: The regulating agent is pillarpentaarene, or a mixture of pillarpentaarene and a compound containing an electron-withdrawing group; When the regulating agent is a mixture of pillarpentaarene and a compound containing an electron-withdrawing group, the molar ratio of the pillarpentaarene to the charge transfer eutectic is 0.2-1, and the molar ratio of the compound containing an electron-withdrawing group to the charge transfer eutectic is 1-2; When the regulator is pillarpentaarene, the molar ratio of the regulator to the charge transfer eutectic is 1-2.

6. The method for preparing a eutectic iodine adsorbent based on pillar aromatics according to claim 4, characterized in that: After obtaining the first mixed solution, the method further comprises the following steps: A second solvent is added to the first mixed solution.

7. The method for preparing a eutectic iodine adsorbent based on pillar aromatics according to claim 6, characterized in that: The first solvent is dichloromethane, and the second solvent is n-hexane.

8. A eutectic iodine adsorbent based on pillar aromatics, characterized in that: Including a charge transfer eutectic, said EtP6-TFTN a or EtP6-TFTN b The charge transfer eutectic is obtained by the preparation method of the pillar aromatic hydrocarbon-based eutectic iodine adsorbent according to any one of claims 2 to 7.

9. The eutectic iodine adsorbent based on pillar aromatics according to claim 8, characterized in that: The EtP6-TFTN a 、EtP6-TFTN b All of them belong to the triclinic system, and their space groups are all P-1; The EtP6-TFTN a The unit cell parameters are: c= α=108.963(4)°, β=108.419(4)°, γ=105.431(4)°, The EtP6-TFTN b The unit cell parameters are: α=68.459(4)°, β=89.110(5)°, γ=66.900(4)°, 10. Application of a pillar aromatic hydrocarbon-based adsorbent in iodine adsorption process.

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