Aluminum-crown ether-based polyoxometalate, and preparation method and application thereof
Patent Information
- Application Number
- CN202610575698.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-04-28
- Publication Date
- 2026-09-15
AI Technical Summary
目前，已经公开了部分冠醚-POMs配合物用于硫芥的选择性氧化，然而存在反应速率低、选择性差、稳定性低以及难以回收利用的问题
本发明中Al3+离子能够与二环己烷并-18-冠醚-6的空腔结合，形成带正电的金属醚配合离子[Al(C20H36O6)(DMSO)]3+，该离子能够与[PMo12O40]3-聚阴离子结合形成铝-冠醚基多金属氧酸盐。三价Al3+离子相比二价离子（如Sr2+）具有更高的电荷密度和强路易斯酸性，能高效吸附并活化硫芥模拟物分子中的C-S键，提升反应速率。且Al3+离子具有很强的极化力，能温和活化氧化剂（如H2O2），使反应精准控制在亚砜阶段，因此具有良好的选择性。本发明中铝-冠醚基多金属氧酸盐作为非均相催化剂，不溶于体系，实现了催化剂回收利用。
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Abstract
Description
Technical Field
[0001] This invention relates to the field of catalyst materials technology, specifically to an aluminum-crown ether-based polyoxometalate, its preparation method, and its application. Background Technology
[0002] The information disclosed in this background section is intended only to enhance understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.
[0003] Sulfur mustard (HD), also known as mustard gas, was widely used as a chemical weapon in the later stages of World War I. As a war agent, its most significant toxicity was causing skin blistering, erosion, and necrosis in those exposed. Currently, the main degradation pathways of sulfur mustard include hydrolysis, dehydrohalogenation, and oxidation. Among these, hydrolysis and dehydrohalogenation have relatively low reaction rates, limiting their practical application. Traditional oxidative degradation relies on large amounts of corrosive oxidants, such as hypochlorite, leading to negative environmental impacts. Selectively oxidizing sulfur mustard to sulfoxides is a milder and more environmentally friendly method. Therefore, a suitable catalyst is urgently needed to selectively oxidize it to non-toxic sulfoxides.
[0004] Polyoxometalates (POMs) are a class of ordered nanoclusters composed of multiple metal oxide octahedrons linked by oxygen atoms. They possess advantages such as thermodynamic stability, chemical stability, multi-electron redox capabilities, controllable size, and precise structure, leading to their widespread application in energy storage, catalysis, and sensors. Furthermore, crown ethers, as macrocyclic polyether compounds, have broad applications in chemistry, particularly in phase transfer catalysis, due to their unique molecular structure and functional properties. Crown ethers typically possess one or more continuous ether oxygen atom rings, enabling them to form stable complexes with metal ions. Currently, some crown ether-POMs complexes have been disclosed for the selective oxidation of sulfur mustard; however, they suffer from low reaction rates, poor selectivity, low stability, and difficulty in recycling. Summary of the Invention
[0005] To overcome the above problems, the present invention provides an aluminum-crown ether-based polyoxometalate, its preparation method and application.
[0006] To achieve the above technical objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides an aluminum-crown ether-based polyoxometalate with the molecular formula [Al(C 20 H 36 O6)(DMSO)](PMo 12 O 40 (DMSO).
[0007] Aluminum-crown ether polyoxometalates, in monoclinic P2 / c Crystallization in space group, asymmetric unit consisting of a [PMo 12 O 40 ] 3- Polyanionic, one [Al(C 20 H 36 O6)(DMSO)] 3+ It consists of a cation and one molecule of free DMSO. [PMo 12 O 40 ] 3- Polyanionic α-Keggin The structure consists of 12 {MoO6} octahedra and 1 {PO4} tetrahedron. [Al(C 20 H 36 O6)(DMSO)] 3+ In cations, Al 3+ The ions are completely concentrated in the cavity of dicyclohexano-18-crown ether-6, coordinated with 6 oxygen atoms from the crown ether, and coordinated with oxygen in 1 molecule of DMSO.
[0008] A second aspect of the present invention provides a method for preparing the aluminum-crown ether polyoxometalate described in the first aspect, comprising the following steps: (1) Disperse the aluminum source and dicyclohexano-18-crown ether-6 in water, and then add phosphomolybdic acid (H3PMo) 12 O 40 Aqueous solution, stirred, precipitate collected, precipitate dried to obtain precursor; (2) The precursor was dispersed in hot dimethyl sulfoxide (DMSO) and cooled to obtain aluminum-crown ether polyoxometalate.
[0009] In one or more embodiments, in step (1), the aluminum source includes one or more of aluminum chloride or aluminum nitrate.
[0010] In one or more embodiments, in step (1), the molar ratio of aluminum source and dicyclohexano-18-crown ether-6 is (0.9~1.2):1, preferably 1:1.
[0011] In one or more embodiments, in step (1), the concentration of the aluminum source in the water is 0.027~0.036 mol / L.
[0012] In one or more embodiments, in step (1), the aluminum source reacts with phosphomolybdic acid (H3PMo) 12 O 40 The molar ratio of ) is 1:(0.4~1.0).
[0013] In one or more embodiments, in step (1), the stirring temperature is 25~45℃ and the stirring time is 1.5~3 h.
[0014] In one or more embodiments, in step (2), the temperature of dimethyl sulfoxide (DMSO) is 60~80°C.
[0015] A third aspect of the present invention provides the application of the aluminum-crown ether polyoxometalate obtained in the first aspect or the aluminum-crown ether polyoxometalate prepared by the preparation method described in the second aspect in the catalytic degradation of sulfur mustard mimics.
[0016] In one or more embodiments, the sulfur mustard mimic includes 2-chloroethyl ethyl sulfide.
[0017] In one or more embodiments, the degradation medium is seawater.
[0018] A fourth aspect of the present invention provides a method for catalytically degrading a sulfur mustard mimic, comprising the following steps: The catalyst is packed into a fixed-bed reactor for continuous flow catalytic degradation reaction; the catalyst is the aluminum-crown ether polyoxometalate obtained in the first aspect or the aluminum-crown ether polyoxometalate prepared by the preparation method described in the second aspect.
[0019] In one or more embodiments, the degradation medium is seawater.
[0020] The beneficial effects of this invention are as follows: In this invention, Al 3+ The ion can bind to the cavity of dicyclohexano-18-crown ether-6 to form a positively charged metal ether complex ion [Al(C 20 H 36 O6)(DMSO)] 3+ This ion can react with [PMo] 12 O 40 ] 3- Polyanionic bonding forms aluminum-crown ether polyoxometalates. Trivalent Al 3+ Compared to divalent ions (such as Sr), ions 2+ It possesses higher charge density and strong Lewis acidity, enabling it to efficiently adsorb and activate CS bonds in sulfur mustard mimic molecules, thereby increasing the reaction rate. Furthermore, Al... 3+ The ions possess strong polarizing power and can gently activate oxidants (such as H₂O₂), allowing the reaction to be precisely controlled at the sulfoxide stage, thus exhibiting good selectivity. In this invention, aluminum-crown ether polyoxometalate is used as a heterogeneous catalyst, insoluble in the system, enabling catalyst recovery and utilization.
[0021] Furthermore, due to the poor solubility of sulfur mustard in water, catalytic decontamination reactions are typically carried out in organic solvents. However, these methods generate large amounts of organic waste, complicating subsequent treatment and hindering large-scale application. The aluminum-crown ether-based polyoxometalate provided by this invention has a crown ether group and its attached organic framework that can construct an amphiphilic supramolecular structure. Its cavities or side chains enrich CEES molecules onto the catalyst surface through hydrophobic interactions. This local enrichment effect significantly increases the contact probability between the substrate and the active site, effectively overcoming mass transfer resistance in seawater media. Attached Figure Description
[0022] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.
[0023] Figure 1 Here are schematic diagrams of the structures of the aluminum-crown ether polyoxometalates prepared in Examples 1-6; Figure 2 PXRD of the aluminum-crown ether polyoxometalate prepared in Example 2; Figure 3 A method for the catalytic degradation of sulfur mustard mimics by aluminum-crown ether polyoxometalates; Figure 4 Long-term stability of the catalyst in catalytic degradation of sulfur mustard mimics under continuous flow mode. Detailed Implementation
[0024] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.
[0025] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.
[0026] To enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below with reference to specific embodiments.
[0027] Example 1 Preparation of aluminum-crown ether polyoxometalates: Disperse 0.3 mmol of anhydrous aluminum chloride and 0.3 mmol of dicyclohexano-18-crown ether-6 in 10 mL of water, mix thoroughly, and then add 10 mL of 0.024 mol / L phosphomolybdic acid (H3PMo). 12 O 40 The aqueous solution was stirred at 25°C for 2 h; the precipitate was collected by filtration and dried to obtain the precursor.
[0028] The precursor was dispersed in dimethyl sulfoxide (DMSO) at 60 °C, and after cooling, well-formed orange-yellow blocky crystals, namely aluminum-crown ether polyoxometalate, were obtained with a yield of 37%.
[0029] Example 2 Preparation of aluminum-crown ether polyoxometalates: Disperse 0.3 mmol of anhydrous aluminum chloride and 0.3 mmol of dicyclohexano-18-crown ether-6 in 10 mL of water, mix thoroughly, and then add 10 mL of 0.018 mol / L phosphomolybdic acid (H3PMo). 12 O 40 The aqueous solution was stirred at 25°C for 2 h; the precipitate was collected by filtration and dried to obtain the precursor.
[0030] The precursor was dispersed in dimethyl sulfoxide (DMSO) at 70 °C, and after cooling, well-formed orange-yellow blocky crystals, namely aluminum-crown ether polyoxometalate, were obtained with a yield of 48%.
[0031] Example 3 Preparation of aluminum-crown ether polyoxometalates: Disperse 0.3 mmol of anhydrous aluminum chloride and 0.3 mmol of dicyclohexano-18-crown ether-6 in 10 mL of water, mix thoroughly, and then add 10 mL of 0.018 mol / L phosphomolybdic acid (H3PMo). 12 O 40 The aqueous solution was stirred at 45°C for 2 h; the precipitate was collected by filtration and dried to obtain the precursor.
[0032] The precursor was dispersed in dimethyl sulfoxide (DMSO) at 70 °C, and after cooling, well-formed orange-yellow blocky crystals, namely aluminum-crown ether polyoxometalate, were obtained with a yield of 32%.
[0033] Example 4 Preparation of aluminum-crown ether polyoxometalates: Disperse 0.3 mmol of anhydrous aluminum chloride and 0.3 mmol of dicyclohexano-18-crown ether-6 in 10 mL of water, mix thoroughly, and then add 10 mL of 0.030 mol / L phosphomolybdic acid (H3PMo). 12 O 40 The aqueous solution was stirred at 25°C for 2 h; the precipitate was collected by filtration and dried to obtain the precursor.
[0034] The precursor was dispersed in dimethyl sulfoxide (DMSO) at 80 °C, and after cooling, well-formed orange-yellow blocky crystals, namely aluminum-crown ether polyoxometalate, were obtained with a yield of 37%.
[0035] Example 5 Preparation of aluminum-crown ether polyoxometalates: Disperse 0.3 mmol of anhydrous aluminum chloride and 0.3 mmol of dicyclohexano-18-crown ether-6 in 10 mL of water, mix thoroughly, and then add 10 mL of 0.024 mol / L phosphomolybdic acid (H3PMo). 12 O 40 The aqueous solution was stirred at 35°C for 2 h; the precipitate was collected by filtration and dried to obtain the precursor.
[0036] The precursor was dispersed in dimethyl sulfoxide (DMSO) at 80 °C, and after cooling, well-formed orange-yellow blocky crystals, namely aluminum-crown ether polyoxometalate, were obtained with a yield of 43%.
[0037] Example 6 Preparation of aluminum-crown ether polyoxometalates: Disperse 0.3 mmol of anhydrous aluminum chloride and 0.3 mmol of dicyclohexano-18-crown ether-6 in 10 mL of water, mix thoroughly, and then add 10 mL of 0.012 mol / L phosphomolybdic acid (H3PMo). 12 O 40 The aqueous solution was stirred at 35°C for 2 h; the precipitate was collected by filtration and dried to obtain the precursor.
[0038] The precursor was dispersed in dimethyl sulfoxide (DMSO) at 70 °C, and after cooling, well-formed orange-yellow blocky crystals, namely aluminum-crown ether polyoxometalate, were obtained with a yield of 26%.
[0039] Figure 1 Table 1 shows the structural schematic diagrams of the aluminum-crown ether polyoxometalates prepared in Examples 1-6, and the crystallographic data of the aluminum-crown ether polyoxometalates prepared in Examples 1-6.
[0040] Table 1. Crystallographic data of aluminum-crown ether polyoxometalates
[0041] Figure 2 The PXRD of the aluminum-crown ether polyoxometalate prepared in Example 2 was obtained from... Figure 2 It can be determined that the substance prepared in Example 2 is a pure phase aluminum-crown ether-based polyoxometalate.
[0042] Experimental Example 1 Figure 3 For a method of catalytic degradation of sulfur mustard mimics by aluminum-crown ether polyoxometalates, refer to Figure 3 , catalytically degrades sulfur mustard mimics.
[0043] The aluminum-crown ether polyoxometalate (0.2 mmol) prepared in Example 2 was loaded into a fixed-bed reactor with an inner diameter of 10 mm, and the entire experimental setup was placed in an oven at 25 °C and allowed to stand for 40 min. A 300 mL seawater solution containing 2-chloroethyl ethyl sulfide (30 mmol) and H₂O₂ (36 mmol) was injected into the fixed-bed reactor using a peristaltic pump at a flow rate of 0.3 mL / min. -1 The eluent was extracted with ethyl acetate and analyzed by gas chromatography, using chlorobenzene as an internal standard. The conversion rate of 2-chloroethyl ethyl sulfide was found to be 92%, and the selectivity for oxidation to sulfoxide was 87%.
[0044] Experiment Example 2 The aluminum-crown ether polyoxometalate (0.3 mmol) prepared in Example 2 was loaded into a fixed-bed reactor with an inner diameter of 10 mm, and the entire experimental setup was placed in an oven at 25 °C and allowed to stand for 40 min. A 300 mL seawater solution containing 2-chloroethyl ethyl sulfide (30 mmol) and H₂O₂ (36 mmol) was injected into the fixed-bed reactor using a peristaltic pump at a flow rate of 0.3 mL / min. -1 The eluent was extracted with ethyl acetate and analyzed by gas chromatography, using chlorobenzene as an internal standard. The conversion rate of 2-chloroethyl ethyl sulfide was found to be 100%, and the selectivity for oxidation to sulfoxide was 90%.
[0045] Experimental Example 3 The aluminum-crown ether polyoxometalate (0.4 mmol) prepared in Example 2 was loaded into a fixed-bed reactor with an inner diameter of 10 mm, and the entire experimental setup was placed in an oven at 25 °C and allowed to stand for 40 min. A 300 mL seawater solution containing 2-chloroethyl ethyl sulfide (30 mmol) and H₂O₂ (36 mmol) was injected into the fixed-bed reactor using a peristaltic pump at a flow rate of 0.3 mL / min. -1The eluent was extracted with ethyl acetate and analyzed by gas chromatography, using chlorobenzene as an internal standard. The conversion rate of 2-chloroethyl ethyl sulfide was found to be 100%, and the selectivity for oxidation to sulfoxide was 86%.
[0046] Experiment Example 4 The aluminum-crown ether polyoxometalate (0.3 mmol) prepared in Example 2 was loaded into a fixed-bed reactor with an inner diameter of 20 mm, and the entire experimental setup was placed in an oven at 25 °C and allowed to stand for 40 min. A 300 mL seawater solution containing 2-chloroethyl ethyl sulfide (30 mmol) and H₂O₂ (36 mmol) was injected into the fixed-bed reactor using a peristaltic pump at a flow rate of 0.4 mL / min. -1 The eluent was extracted with ethyl acetate and analyzed by gas chromatography, using chlorobenzene as an internal standard. The conversion rate of 2-chloroethyl ethyl sulfide was found to be 92%, and the selectivity for oxidation to sulfoxide was 90%.
[0047] Experimental Example 5 The aluminum-crown ether polyoxometalate (0.4 mmol) prepared in Example 2 was loaded into a fixed-bed reactor with an inner diameter of 20 mm, and the entire experimental setup was placed in an oven at 25 °C and allowed to stand for 40 min. A 300 mL seawater solution containing 2-chloroethyl ethyl sulfide (30 mmol) and H₂O₂ (36 mmol) was injected into the fixed-bed reactor using a peristaltic pump at a flow rate of 0.4 mL / min. -1 The eluent was extracted with ethyl acetate and analyzed by gas chromatography, using chlorobenzene as an internal standard. The conversion rate of 2-chloroethyl ethyl sulfide was found to be 97%, and the selectivity for oxidation to sulfoxide was 86%.
[0048] The results above indicate that aluminum-crown ether polyoxometalates exhibit highly efficient catalytic activity in the degradation of 2-chloroethyl ethyl sulfide in seawater. Under the condition of hydrogen peroxide as an oxidant, they can effectively catalyze the conversion of 2-chloroethyl ethyl sulfide into a non-toxic sulfoxide product (CEESO), rather than a toxic sulfone (CEESO2). The conversion rate can reach 100% within 40 min at 25℃, with a selectivity of 90%.
[0049] Comparative Example 1 The catalyst in Experimental Example 2 was replaced with a crown ether-based polymetallic oxo cluster catalyst (molecular formula [Sr(DCH)]). 18 C6)(DMSO)3][HPMo 12 O 40 ]).
[0050] Crown ether-based polymetallic oxygen cluster catalysts (molecular formula [Sr(DCH)]) 18 C6)(DMSO)3][HPMo 12 O40 The preparation method of ]) is as follows: 0.3 mmol SrCl2·6H2O and 0.3 mmol dicyclohexane 18 Crown ethers Disperse 6 in 10 mL of water, mix and stir well, then add 10 mL of 0.018 mol / L phosphomolybdic acid (H3PMo). 12 O 40 The aqueous solution was stirred at 25°C for 2 hours; the precipitate was collected by filtration and dried to obtain the precursor.
[0051] The precursor was dispersed in dimethyl sulfoxide (DMSO) to form a saturated solution. After the solution was allowed to stand under ambient conditions for two weeks, orange-yellow blocky crystals were formed, which is the strontium-crown ether-based polymetallic oxygen cluster catalyst (molecular formula [Sr(DCH)]). 18 C6)(DMSO)3][HPMo 12 O 40 ]).
[0052] The prepared crown ether-based polyoxometalate cluster catalyst (0.3 mmol) was loaded into a fixed-bed reactor with an inner diameter of 10 mm, and the entire experimental setup was placed in an oven at 25 °C and allowed to stand for 40 min. A 300 mL seawater solution containing 2-chloroethyl ethyl sulfide (30 mmol) and H₂O₂ (36 mmol) was injected into the fixed-bed reactor using a peristaltic pump at a flow rate of 0.3 mL / min. -1 The eluent was extracted with ethyl acetate and analyzed by gas chromatography, using chlorobenzene as an internal standard. The conversion rate of 2-chloroethyl ethyl sulfide was found to be 64%, and the selectivity for oxidation to sulfoxide was 52%.
[0053] Experimental Example 6 The aluminum-crown ether polyoxometalate (0.3 mmol) prepared in Example 2 was loaded into a fixed-bed reactor with an inner diameter of 10 mm, and the entire experimental setup was placed in an oven at 25 °C and allowed to stand for 40 min. A 300 mL seawater solution containing 2-chloroethyl ethyl sulfide (30 mmol) and H₂O₂ (36 mmol) was injected into the fixed-bed reactor using a peristaltic pump at a flow rate of 0.3 mL / min. -1 The system was continuously run, and samples were taken every 2 hours to analyze the degradation efficiency of the sulfur mustard simulants in order to assess the long-term stability of the system.
[0054] Figure 4 To study the long-term stability of the catalyst in the catalytic degradation of sulfur mustard mimics under continuous flow mode, Figure 4This indicates that the catalyst can continuously flow and remain stable for CEES over 14 hours (conversion rate 100%-96%, selectivity 90%-87%).
[0055] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. An aluminum-crown ether-based polyoxometalate, characterized in that, Its molecular formula is [Al(C 20 H 36 O6)(DMSO)](PMo 12 O 40 (DMSO).
2. The method for preparing aluminum-crown ether-based polyoxometalate as described in claim 1, characterized in that, Includes the following steps: (1) Disperse the aluminum source and dicyclohexano-18-crown ether-6 in water, and then add phosphomolybdic acid (H3PMo) 12 O 40 Aqueous solution, stirred, precipitate collected, precipitate dried to obtain precursor; (2) The precursor was dispersed in hot dimethyl sulfoxide (DMSO) and cooled to obtain aluminum-crown ether polyoxometalate.
3. The preparation method according to claim 2, characterized in that, In step (1), the aluminum source includes one or more of aluminum chloride or aluminum nitrate.
4. The preparation method according to claim 2, characterized in that, In step (1), the molar ratio of aluminum source to dicyclohexano-18-crown ether-6 is (0.9~1.2):1, preferably 1:1; Alternatively, in step (1), the concentration of the aluminum source in the water is 0.027~0.036 mol / L.
5. The preparation method according to claim 2, characterized in that, In step (1), the aluminum source reacts with phosphomolybdic acid (H3PMo) 12 O 40 The molar ratio of ) is 1:(0.4~0.1).
6. The preparation method according to claim 2, characterized in that, In step (1), the stirring temperature is 25~45℃ and the stirring time is 1.5~3 h; Alternatively, in step (2), the temperature of dimethyl sulfoxide (DMSO) is 60~80℃.
7. The application of the aluminum-crown ether polyoxometalate as described in claim 1 or the aluminum-crown ether polyoxometalate prepared by the preparation method according to any one of claims 2 to 6 in the catalytic degradation of sulfur mustard mimics.
8. The application as described in claim 7, characterized in that, The sulfur mustard mimic includes 2-chloroethyl ethyl sulfide; Alternatively, the degradation medium may be seawater.
9. A method for catalytically degrading sulfur mustard mimics, characterized in that, Includes the following steps: The catalyst is packed into a fixed-bed reactor for continuous flow catalytic degradation reaction; the catalyst is the aluminum-crown ether polyoxometalate of claim 1 or the aluminum-crown ether polyoxometalate prepared by the preparation method of any one of claims 2 to 6.
10. The method as described in claim 9, characterized in that, The degradation medium is seawater.