Porous, crystalline compound
Patent Information
- Application Number
- EP2023714205
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-03-23
- Filing Date
- 2023-03-20
- Publication Date
- 2025-01-29
AI Technical Summary
Current methods for producing porous crystalline compounds often require non-aqueous media and high temperatures, which are disadvantageous, and there is a need for new compounds suitable for applications in storage, separation, catalysis, and synthesis of high-purity metal oxides or hydroxides.
A method for producing porous crystalline compounds with the formula [Al2(OH)56(RCOO)i2]X4 using an aqueous solution of an aluminum salt, carboxylic acid or their salts, and water-soluble anions, at temperatures between room temperature and 140°C, resulting in highly crystalline materials with defined porosity.
The method enables the production of porous crystalline compounds with high surface area and water absorption capacity, suitable for adsorption of gases and vapors, and effective in removing anionic dyes and pollutants, making them suitable for various industrial applications.
Smart Images
Figure 1.1
Abstract
Description
[0001] POROUS, CRYSTALLINE COMPOUND
[0002] The invention relates to porous, crystalline compounds and a method for their preparation and uses.
[0003] Due to their defined structure, crystalline, porous compounds with defined porosity are promising candidates in the field of storage and separation of liquids or gases, for water sorption (also in connection with the regulation of air humidity, water extraction and cooling), as catalysts, adjuvants, carrier materials or solubilizers, as ion exchangers, for the adsorption of dyes, as fillers for membranes and as starting materials for the synthesis of high-purity metal oxides or hydroxides.
[0004] Metal-organic frameworks (MOFs) have a lattice structure and are made up of metal-based inorganic units, often oxides or hydroxides, which are connected via organic linker molecules.
[0005] In the article Li et al.: “Recent advances in aluminium-based metal-organic frameworks (MOF) and its membrane applications”, Journal of Membrane Science, Volume 615, December 2020, 118493 https: / / doi.Org / 10.1016 / j.memsci.2020.118493 an overview of the known aluminium-based metal-organic frameworks (MOF) and their application is given.
[0006] In [Jung, Kyung-Won et al., "Green synthesis of aluminum-based metal organic framework for the removal of azo dye acid black 1 from aqueous media”, Journal of Industrial and Engineering Chemistry, Vol. 67, 2019, pp. 316-325], aluminum-based MOFs with dicarboxylate linkers, which are linked via both carboxylate groups, are presented. This MOF crystallizes in the characteristic MIL-53 structure, which the authors call a butterfly-like structure. Due to their good ability to adsorb the dye acid black 1, the MOFs in question are proposed as adsorbents for wastewater treatment.
[0007] [Mani, Mohan Raj et al. / 'Enhanced nucleation of polypropylene by metal-organic frameworks (MOFs) based on aluminum dicarboxylates: influence of structural features, RSC Advances, 2016, Vol. 6, pp. 1907 - 1912] also describes aluminum-based MOFs with the characteristic MIL-53 structure. The organic linker has carbon chains with a length between 2 and 10 carbon atoms.
[0008] Porous, crystalline salts with MOF-like permanent porosity are known from Gosselin et al., "Elaboration of Porous Salts," J. Am. Chem. Soc. 2021, 143, 37, 14956-14961. In the article by Smolders et al., "A precursor method for the synthesis of new Ce(IV) MOFs with reactive tetracarboxylate linkers," Chemical Communications 2018, 54, 876-879; DOI https: / / doi.org / 10.1039 / C7CC08200B, the use of molecular metal-oxygen carboxylate clusters as starting materials / precursors for the preparation of Ce(IV) MOFs is reported, whereby the framework is formed by replacing the monocarboxylate ions with dicarboxylate ions.
[0009] WO 2021 / 048741 A3 describes a metal-organic framework (MOF) as part of a heterogeneous catalyst system for the oligomerization of olefins, whose activity is 20 times higher than that of conventional homogeneous catalysts. The system's easy removal is advantageous compared to monomolecular catalysts. The MOF contains at least one ligand with an N-heteroaromatic ring.
[0010] In Bagherpour et al.: “Investigating the Performance of Carboxylate-Alumoxane Nanoparticles as a Novel Chemically Functionalized Inhibitor on Asphaltene Precipitation”, ACS Omega 2020, 5, 16149, methoxyacetate-functionalized alumoxanes are used to prevent the precipitation of asphalt in crude oils.
[0011] The document EP 22 34 922 B1 describes the production of needle-shaped high-purity boehmite (aluminum oxide hydroxide), which can be added to polymers for reinforcement, from the precursor AI(OH) w (R 1 ) x (R 2 )y(R 3 )z to the content, where R 1 , R 2 and R 3 can be different carboxylates.
[0012] US Pat. No. 8,658,562 B2 and US Pat. No. 8,907,114 B2 describe a method for producing a MOF based on aluminum oxide with carboxylate ligands or azobenzene carboxylate ligands in non-aqueous media at temperatures above 100°C. The material is intended for the storage and separation of gases or liquids. The use of non-aqueous media in the production of the corresponding MOFs and temperatures above 100°C are disadvantageous.
[0013] In Reinsch et al.: “A new AI-MOF based on a unique column-shaped inorganic building unit exhibiting strongly hydrophilic sorption behavior”, Chemical Communications 2012, 48, 9486-9488; DOI https: / / doi.org / 10.1039 / C2CC34909D, the preparation of an AI-MOF based on known aluminum hydroxide oxide ions bridged by 2-aminoterephthalate ligands is described.
[0014] The object of the invention is to provide new porous crystalline compounds.
[0015] In a further aspect, the invention provides a process for producing novel porous crystalline compounds. Furthermore, the invention provides a process for producing the novel porous crystalline compounds that can be carried out in aqueous media and at reaction temperatures between room temperature and 140°C with yields of more than 50%.
[0016] In a particular aspect, it is an object of the invention to provide a process for the preparation of novel porous crystalline compounds which can be carried out in a one-pot reaction.
[0017] The object of the invention is achieved by porous crystalline compounds or porous crystalline compounds according to the following formula:
[0018] [AI24(OH)56(RCOO)I2]X4 where R can be hydrogen or a branched or unbranched, saturated or unsaturated, functionalized or unfunctionalized hydrocarbon chain with a length of 1 to 8 carbon atoms and where the functionalization is selected from the group -OH, -F, -Cl, -Br, -I, -SH, -NO2, -CHO, -COOH, -SO3H, -NH2 and where R can be the same or different and where X can be the same or different and is an anion, preferably a monovalent anion, particularly preferably a monovalent anion selected from the group Cl; Br, I; OH; SCN; NO, HSO, HS, CIO3; and CIO or mixtures of these anions.
[0019] In a particular aspect, the object of the invention is achieved by porous, crystalline compounds which have cationic [Al24(OH)s6(RCOO)i2] 4+ - Cages have the cationic [Al24(OH)s6(RCOO)i2] 4+ - Cages of 8 trinuclear building blocks of the composition {AI3(p3OH)(2-OH)3}5+ , 24 OH- and 12 RCOO' ions and each of the three aluminum cations Al 3+ octahedrally coordinated with 5 OH- and one RCOO' via an oxygen atom and where the {A (p3-OH)( 2-OH)3} 5+ Building units are arranged on the corners of a cube and where adjacent {Al3(p3-OH)( 2-OH)s} 5+ -building units are each linked by 2 OH' and 1 RCOO'.
[0020] Here, ps-OH means that one OH' ion contains three aluminum cations Al 3+ bridged and p2-OH two.
[0021] In another special aspect, the cationic [AI24(OH)56(RCOO)i2] 4+ - Cages arranged cubically, centered inside.
[0022] In a further aspect, the crystalline porous compound according to the invention contains monovalent anions which occupy 2 / 3 of the octahedrally arranged free sites, which are formed by the cubic body-centered arrangement of the cationic [AI24(OH)56(RCOO)i2] 4+ - Cages surrender, occupy.
[0023] In a particular aspect, the object of the invention is achieved by crystalline porous compounds selected from the group [AI24(OH)56(CH3COO)i2]Cl4, [AI24(OH)56(CH3COO)i2]Br4, [AI 24 (OH)56(CH3COO)I2]I4, [AI 24 (OH)56(CH3COO)i2](OH)4, [AI 24 (OH)56(CH3COO)I2](SCN)4, [AI 24 (OH)56(CH3COO)I2](NO3)4, [AI 24 (OH)56(CH3COO)I2](HSO4)4, [AI 24 (OH)56(CH3COO)I2](HS)4, [AI 24 (OH)56(CH3COO)I2](CIO3)4, [AI 24 (OH)56(CH3COO)I2](CIO4)4, [AI 24 (OH)56(C2H5COO)12]CI4, [AI 24 (OH)56(HCOO)x(CH3COO)i2-x]CI4with x = 1 ; 2, [AI 24 (OH)56(HSCH2COO)i2]CI4, [AI 24 (OH)56(CH3COO)i2]ClyBr4.y with y = 0 to 4, [AI 24 (OH)56(CH3COO)i2]Bryl4-y with y = 0 to 4.
[0024] In a further aspect, the object of the invention is achieved by a process for producing crystalline porous compounds comprising the following steps: i. Providing an aqueous solution of an aluminum salt. ii. Adding the carboxylic acid or the mixture of carboxylic acids or their salts. iii. Optionally adding a water-soluble salt of the anion or the mixture of different anions X. iv. Heating the mixture from step ii or iii at RT to 140°C for 4 weeks to 2 minutes. v. Optionally allowing the mixture to cool to room temperature. vi. Separating the solid from the solution, for example by filtration, spray drying or centrifugation. vii. Washing the resulting solid with water and / or alcohols. viii. Drying the washed solid.
[0025] Water-soluble salts are generally known to the person skilled in the art, for example sodium, potassium, or ammonium salts. In a particular embodiment of the process, the anion or anions X of the water-soluble salt from step iii are selected from Cl; Br; I; OH; SCN; NO3; HSO4; HS; ClO3; and ClO4-, or mixtures of these anions.
[0026] The synthesis of the compounds according to the invention can be carried out as a very rapid one-pot synthesis in aqueous media using very favorable starting materials. Advantageously, the tempering step (iv) can also be carried out in a flow reactor.
[0027] The compounds according to the invention [AI 24(OH)56(R-COO)i2]X4wherein R is hydrogen or a branched or unbranched, saturated or unsaturated, functionalized or non-functionalized hydrocarbon chain with a length of 1 to 8 carbon atoms and wherein the functionalization is selected from the group -OH, -F, -Cl, -Br, -I, -SH, -NO2, -CHO, -COOH, -SO3H, -NH2and wherein R can be the same or different and wherein X can be the same or different and is an anion, preferably a monovalent anion, particularly preferably a monovalent anion selected from the group Cl; Br, I; OH; SCN; NO3; HSO4; HS; ClO3; and ClO4 _or mixtures of these anions, can be assigned to the group of porous metal carboxylates, which also include the so-called metal-organic frameworks (MOFs). In the latter type of compound, an organic ligand acts as a "linker" between the inorganic building blocks. In the case of the invention, the carboxylate ions (RCOO) coordinate to aluminum ions without bridging the inorganic building blocks. The cationic aluminum carboxylate building blocks crystallize with various anions to form highly crystalline salts. Compared to non-crystalline porous materials, the new porous crystalline aluminum carboxylates exhibit very defined pores in shape and size.These defined properties make these compounds very interesting for applications in the field of storage and separation of liquids or gases, catalysis, as adjuvants or solubilizers and as starting material for the synthesis of high-purity metal oxides or hydroxides as well as as starting material for MOF syntheses by ligand-linker exchange.
[0028] The X-ray characterization of the compounds of the invention, [Al24(OH)56(RCOO)I2]X4, demonstrates the uniqueness of this compound type. Figure 1 shows a representation of the structure of the cationic cages. The structure of [Al24(OH)5e(CH3COO)i2]Cl4 is described below as an example.
[0029] Al 3+ , OH- and acetate ions (CH3COO') form a cationic cubic cage of composition [Al24(OH)5e(CH3COO)i2] 4+ . Each aluminum cation (Al 3+) is octahedrally surrounded (coordinated) by 5 hydroxide ions (OH j and one oxygen atom of an acetate ion (CHsCOO'). The hydroxide ions bridge (p2-OH and p3-OH) two or three Al 3+ - ions Figure 1 a. The structure of the cationic cage is obtained when eight trinuclear building blocks of the composition {AI3(p3-OH)( 2-OH)3} 5+ , located at the corners of a cube (Figure 1 b), are linked via 24 OH' and 12 CH3COO' ions (Figure 1 c). Neighboring trinuclear units are each linked via 2 OH' ions and 1 CH3COO' ion.
[0030] In the crystal structure, the cationic cages form a body-centered cubic arrangement. The arrangement of the cationic cages in the unit cell is shown in Figure 2.
[0031] The anions are randomly distributed in the octahedral interstices, with only two-thirds of the octahedral interstices occupied. The unit cell contains two formula units. The lattice parameters of the compounds are listed in Table 1.
[0032] The presence of highly ordered crystalline structures is clearly evident in the powder diffractograms (Figures 3, 4, 5, and 6) due to the narrow half-width of the reflections, the high signal-to-background ratio at high diffraction angles (20°), and the absence of an amorphous halo. The different ionic radii of the anions X and the different size of R lead to significant shifts in the reflection positions (Figures 3, 4, and 5). Reaction temperatures between room temperature (25 °C) and 140 °C lead to the inventive result (Figure 6). The formation of the inventive compound is clearly evident from the specific reflections in the powder diffractograms.
[0033] Table 1: Crystal structure parameters of [Al24(OH)56(RCOO)i2]X4, refined using the Rietveld method (*1) or the Le Bail method (*2) based on X-ray powder diffraction data. The new compounds [Al24(OH)56(RCOO)i2]X4 are very suitable for the adsorption of gases and vapors (Table 2). Nitrogen sorption measurements at 77 K yielded a specific surface area of up to 940 m². 2 / g. The water adsorption properties vary greatly with the activation temperature and the anion (X). A maximum water absorption of 0.46 g / g is observed for the OH _ containing sample was observed.
[0034] Table 2: Specific surface areas determined by nitrogen sorption measurements (77 K) and maximum water absorption capacities of [Al24(OH)s6(RCOO)i2]X4 determined by water vapor sorption measurements (298 K).
[0035] The new compounds can be prepared as dispersions with particle sizes in the range of 100–1000 nm (Table 3). This is of interest for coating substrates or incorporating them into polymers (mixed-matrix membranes).
[0036] Table 3: Hydrodynamic particle diameters of [Al24(OH)s6(RCOO)i2]X4, determined by dynamic light scattering, depending on composition and reaction regime (a to g (see synthesis instructions)).
[0037] The new compounds [Al24(OH)s6(RCOO)i2]X4 are highly suitable as adsorbents for anions due to their structure and high positive surface charge. For example, anionic dyes can be removed quickly and effectively from ethanolic and aqueous solutions by adsorption. Accordingly, the compounds could also be suitable as substrates for the production of pigments. Furthermore, the adsorption of anionic molecules (both inorganic and organic), such as pollutants from water bodies, is possible. Materials and Methods
[0038] Methods
[0039] Information on chemicals and equipment used is summarized in Tables 4 and 5.
[0040] Table 4: Chemicals used, manufacturers and purities.
[0041] Table 5: Measurement methods and equipment used. Synthesis instructions:
[0042] 1a-d) Preparation of [A OH CHsCOO CL in a 14 mL Duran® glass reactor at a) 70 °C, b) 80 °C, c) 90 °C, d) 100 °C:
[0043] In a 14 mL Duran®^Glase reactor, 1.6 mL of water and 0.75 mL of an aqueous solution of AlCh (1.44 mol L' 1 , 1.08 mmol). 0.938 mL (5.76 mol L' 1 , 5.4 mmol) diluted acetic acid and 2.7 mL (2 mol L' 1 , 5.4 mmol) diluted
[0044] Sodium hydroxide solution is added. The glass reactor is sealed and heated in an aluminum block for 2 hours with stirring at a) 70 °C, b) 80 °C, c) 90 °C, d) 100 °C.
[0045] After cooling to room temperature, the precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours. 1e) Production of fAl24(OH)56(CH3COO)i2lCl4 in a flow reactor at 95 °C:
[0046] 2.61 g (10.8 mmol) AlCh x 6 H2O are dissolved in 16.1 mL H2O. 9.38 mL (5.76 mol L' 1 , 54 mmol) diluted acetic acid and 27 mL (2 mol L' 1 , 54 mmol) of diluted sodium hydroxide solution is added. The solution is drawn into a 60 mL syringe using a syringe pump. Subsequently, 50 mL of the solution is pumped at a flow rate of 200 mL / h through a PTFE tube (15 mL total volume), which is heated to 95 °C in an oil bath.
[0047] The dispersion of the colorless product is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at a speed of 10,000 rpm. The resulting mixture is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours. lf) Preparation of fAl24(OH)56(CH3COO)i2lCl4 in a 10 L round-bottom flask under reflux (rf):
[0048] 434.6 g (1.8 mol) of AlCh x 6 H2O are dissolved in 5 L of H2O in a 10 L round-neck flask. 4.5 L of an aqueous sodium hydroxide solution (2 mol L') are added to this solution. 1, 9 mol) and 516 mL acetic acid (9 mol). The solution is heated and stirred under reflux for 2 hours. After cooling to room temperature, the supernatant clear solution is decanted and the colorless precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at a speed of 10,000 revolutions per minute. Then, for washing, it is taken up twice with water and ethanol and centrifuged again for separation. Afterwards, it is dried at room temperature for 12 hours. lg) Preparation of in a 30 mL steel autoclave under hydrothermal conditions:
[0049] In a 30 mL Teflon vessel, 2.15 mL of water and 1 mL of an aqueous solution of AlCh (1.44 mol L' 1 , 1.44 mmol). 1.25 mL (5.76 mol L' 1 , 7.2 mmol) diluted acetic acid and 3.6 mL (2 mol L' 1, 7.2 mmol) of diluted sodium hydroxide solution is added. The Teflon insert is sealed with a Teflon lid and placed in a steel autoclave. The sealed steel autoclave is then heated in an oven at 140 °C for 30 hours.
[0050] After cooling to room temperature, the precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours.
[0051] 1 h) Preparation of fAl24(OH)56(CH3COO)i2lCl4 in an Erlenmeyer flask at room temperature:
[0052] In a 50 mL Erlenmeyer flask, 8.6 mL of water and 4 mL of an aqueous solution of AlC (1.44 mol U 1 , 5.76 mmol). 5 mL (5.76 mol L' 1, 28.8 mmol) diluted acetic acid and 14.4 mL (2 mol L' 1 , 28.8 mmol) of diluted sodium hydroxide solution. The Erlenmeyer flask is sealed with a stopper and left to stand for 4 weeks at room temperature (25 °C).
[0053] The precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours.
[0054] 2) Preparation of fAl24(OH)56(CH3COO)i2lBr4 in a 14 mL Duran® glass reactor at 90 °C:
[0055] In a 14 mL Duran® glass reactor, 2 mL of water and 3 mL of an aqueous solution of NaAIO2 (0.36 mol L' 1 , 1 .08 mmol). 0.75 mL of dilute acetic acid (5.76 mol L' 1, 4.32 mmol). Then, 0.27 mL of an aqueous solution of NaBr (4 mol L' 1 , 1.08 mmol). The glass reactor is sealed and heated in an aluminum block for 2 hours with stirring at 90 °C.
[0056] After cooling to room temperature, the precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours.
[0057] 3) Preparation of in a 14 mL Duran® glass reactor at 90 °C:
[0058] In a 14 mL Duran® glass reactor, 2 mL of water and 3 mL of an aqueous solution of NaAIO2 (0.36 mol L' 1 , 1 .08 mmol). 0.75 mL of dilute acetic acid (5.76 mol L' 1, 4.32 mmol). Then, 0.27 mL of an aqueous solution of NaI (4 mol U 1 , 1.08 mmol). The glass reactor is sealed and heated in an aluminum block for 2 hours with stirring at 90 °C.
[0059] After cooling to room temperature, the precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours.
[0060] 4) Preparation of fAl24(OH)56(CH3COO)i2l(OH)4 in a 14 mL Duran® glass reactor at 90 °C:
[0061] In a 14 mL Duran® glass reactor, 2.25 mL of water and 3 mL of an aqueous solution of NaAlO2 (0.36 mol L 1 , 1 .08 mmol). 0.75 mL of dilute acetic acid (5.76 mol L'1 , 4.32 mmol). The glass reactor is sealed and heated in an aluminum block for 2 hours with stirring at 90 °C.
[0062] After cooling to room temperature, the precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours.
[0063] 5) Preparation of fAl24(OH)56(CH3COO)i2l(SCN)4 in a 14 mL Duran® glass reactor at 90 °C:
[0064] In a 14 mL Duran® glass reactor, 2.73 mL of water and 2.25 mL of an aqueous solution of NaAIO2 (0.36 mol L' 1 , 0.81 mmol). 0.75 mL of dilute acetic acid (5.76 mol L' 1, 4.32 mmol). Then, 0.27 mL of an aqueous solution of NaSCN (4 mol L' 1 , 1.08 mmol). The glass reactor is sealed and heated in an aluminum block for 2 hours with stirring at 90 °C.
[0065] After cooling to room temperature, the precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours.
[0066] 6) Preparation of rAl24(OH)56(CH3COO)i2l(NO3)4 in a 14 mL Duran® glass reactor at 90 °C:
[0067] In a 14 mL Duran®^glass reactor, 1.6 mL of water and 0.75 mL of an aqueous solution of AI(NOs)3 (1.44 mol U 1 , 1.08 mmol). 0.938 mL (5.76 mol L' 1, 5.4 mmol) diluted acetic acid and 2.16 mL (2 mol L' 1 , 4.32 mmol) of diluted sodium hydroxide solution is added. The glass reactor is sealed and heated in an aluminum block for 2 hours with stirring at 90 °C.
[0068] After cooling to room temperature, the precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours.
[0069] 7) Preparation of fAl24(OH)56(CH3COO)i2l(HSO4)4 in a 14 mL Duran® glass reactor at 90 °C:
[0070] In a 14 mL Duran®^Glase reactor, 1.6 mL of water and 0.75 mL of an aqueous solution of Al2(SO4)5 (0.72 mol L' 1 , 0.54 mmol). 0.75 mL (5.76 mol L' 1, 4.32 mmol) diluted acetic acid and 2.7 mL (2 mol L' 1 , 5.4 mmol) of diluted sodium hydroxide solution is added. The glass reactor is sealed and heated in an aluminum block for 2 hours with stirring at 90 °C.
[0071] After cooling to room temperature, the precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours.
[0072] 8) Preparation of fAl24(OH)56(CH3COO)i2l(HS)4 in a 14 mL Duran® glass reactor at 90 °C:
[0073] In a 14 mL Duran® glass reactor, 2.73 mL of water and 2.25 mL of an aqueous solution of NaAIO2 (0.36 mol L' 1 , 0.81 mmol). 0.75 mL of dilute acetic acid (5.76 mol L'1 , 4.32 mmol). Then, 0.27 mL of an aqueous solution of Na2S (2 mol L' 1 , 0.54 mmol). The glass reactor is sealed and heated in an aluminum block for 2 hours with stirring at 90 °C.
[0074] After cooling to room temperature, the precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours. 9) Preparation of fAl24(OH)56(CH3COO)i2l(CIO3)4 in a 14 mL Duran® glass reactor at 90 °C:
[0075] In a 14 mL Duran® glass reactor, 2 mL of water and 3 mL of an aqueous solution of NaAIO2 (0.36 mol L' 1 , 1 .08 mmol). 0.75 mL of dilute acetic acid (5.76 mol L' 1, 4.32 mmol). Then, 0.27 mL of an aqueous solution of NaClOs (4 mol L' 1 , 1.08 mmol). The glass reactor is sealed and heated in an aluminum block for 2 hours with stirring at 90 °C.
[0076] After cooling to room temperature, the precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours.
[0077] 10) Preparation of fAl24(OH)56(CH3COO)i2l(CIO4)4 in a 14 mL Duran® glass reactor at 90 °C:
[0078] In a 14 mL Duran® glass reactor, 2.12 mL of water and 3 mL of an aqueous solution of NaAIO2 (0.36 mol L 1, 1 .08 mmol). 0.75 mL of dilute acetic acid (5.76 mol L' 1 , 4.32 mmol). Then, 0.135 mL of an aqueous solution of NaCIO4 (4 mol L' 1 , 0.54 mmol). The glass reactor is sealed and heated in an aluminum block for 2 hours with stirring at 90 °C.
[0079] After cooling to room temperature, the precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours.
[0080] 11) Preparation of in a 14 mL Duran®^glass reactor at 90 °C:
[0081] In a 14 mL Duran®^Glase reactor, 2.88 mL of water and 0.75 mL of an aqueous solution of AlCh (1.44 mol L' 1, 1 .08 mmol). To the solution, add 0.75 mL (2.88 mol U 1 , 2.16 mmol) diluted propionic acid and 1.62 mL (2 mol L' 1 , 3.24 mmol) of diluted sodium hydroxide solution is added. The glass reactor is sealed and heated in an aluminum block for 2 hours with stirring at 90 °C.
[0082] After cooling to room temperature, the precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours.
[0083] 12) Preparation of rAl24(OH)56(HCOO)x(CH3COO)i2-x1Cl4 with x = 1.2 in a 14 mL Duran® glass reactor at 90 °C:
[0084] In a 14 mL Duran®^Glase reactor, 1.97 mL of water and 0.75 mL of an aqueous solution of AlCh (1.44 mol L'1 , 1 .08 mmol). 0.75 mL (5.76 mol U 1 , 4.32 mmol) dilute acetic acid, 0.375 mL (2.88 mol L' 1 , 1.08 mmol) diluted formic acid, and 2.7 mL (2 mol L' 1 , 5.4 mmol) of diluted sodium hydroxide solution is added. The glass reactor is sealed and heated in an aluminum block for 2 hours with stirring at 90 °C.
[0085] After cooling to room temperature, the precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours.
[0086] The compound was dissolved in NaOD and D2O and the incorporation of the two carboxylates was carried out using 1 H-NMR spectroscopy (Figure 7).
[0087] 13) Preparation of fAl24(OH)56(HSCH2COO)i2lCl4 in a 2 mL steel autoclave:
[0088] In a 2 mL Teflon vessel, 296 pL of water and 250 pL of an aqueous solution of AlCh (1.44 mol L' 1 , 0.36 mmol). 94 pL (5.76 mol L' 1 , 0.54 mmol) diluted thioglycolic acid and 360 pL (2 mol L' 1 , 0.72 mmol) of diluted sodium hydroxide solution. The Teflon insert is sealed with a Teflon lid and placed in a steel autoclave. The sealed steel autoclave is then heated in an oven at 100 °C for 50 hours.
[0089] After cooling to room temperature, the precipitate is separated by centrifugation in 2 mL centrifuge tubes for 5 minutes at a speed of 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours.
[0090] 14a) Preparation of rAl24 in a 14 mL Duran® glass reactor at 90 °C:
[0091] In a 14 mL Duran® glass reactor, 2.2 mL of water and 3 mL of an aqueous solution of NaAlO2 (0.36 mol L' 1 , 1 .08 mmol). 0.75 mL of dilute acetic acid (5.76 mol L' 1 , 4.32 mmol). Then, 13.5 pL of an aqueous solution of NaCl (4 mol U 1 , 54 pmol) and 40.5 pL of an aqueous solution of NaBr (4 mol L' 1, 162 mmol). The glass reactor is sealed and heated in an aluminum block for 2 hours with stirring at 90 °C.
[0092] After cooling to room temperature, the precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours.
[0093] 14b) Preparation of fAl24(OH)56(CH3COO)i2lCl2.3Bri.7 in a 14 mL Duran® glass reactor at 90
[0094] In a 14 mL Duran® glass reactor, 2.2 mL of water and 3 mL of an aqueous solution of NaAlO2 (0.36 mol L 1 , 1 .08 mmol). 0.75 mL of dilute acetic acid (5.76 mol L' 1 , 4.32 mmol). Then, 27 pL of an aqueous solution of NaCI (4 mol L1 , 108 pmol) and 27 pL of an aqueous solution of NaBr (4 mol L' 1 , 108 mmol). The glass reactor is sealed and heated in an aluminum block for 2 hours with stirring at 90 °C.
[0095] After cooling to room temperature, the precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours.
[0096] 14c) Preparation of fAl24(OH)56(CH3COO)i2lCl3Br in a 14 mL Duran® glass reactor at 90 °C:
[0097] In a 14 mL Duran® glass reactor, 2.2 mL of water and 3 mL of an aqueous solution of NaAIO2 (0.36 mol L' 1 , 1 .08 mmol). 0.75 mL of dilute acetic acid (5.76 mol L' 1, 4.32 mmol). Then, 40.5 pL of an aqueous solution of NaCl (4 mol L' 1 , 162 pmol) and 13.5 pL of an aqueous solution of NaBr (4 mol L- 1 , 54 mmol). The glass reactor is sealed and heated in an aluminum block for 2 hours with stirring at 90 °C.
[0098] After cooling to room temperature, the precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours.
[0099] 15a) Production of .5I0.5 in the 14 mL Duran® glass reactor at 90 °C:
[0100] In a 14 mL Duran® glass reactor, 2.2 mL of water and 3 mL of an aqueous solution of NaAIO2 (0.36 mol L 1, 1 .08 mmol). 0.75 mL of dilute acetic acid (5.76 mol L' 1 , 4.32 mmol). Then, 13.5 pL of an aqueous solution of NaBr (4 mol L' 1 , 54 pmol) and 40.5 pL of an aqueous solution of NaI (4 mol L 1 , 162 mmol). The glass reactor is sealed and heated in an aluminum block for 2 hours with stirring at 90 °C.
[0101] After cooling to room temperature, the precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours.
[0102] 15b) Production of .7I0.3 in a 14 mL Duran® glass reactor at 90 °C:
[0103] In a 14 mL Duran® glass reactor, 2.2 mL of water and 3 mL of an aqueous solution of NaAIO2 (0.36 mol L 1 , 1 .08 mmol). 0.75 mL of dilute acetic acid (5.76 mol L' 1 , 4.32 mmol). Then, 27 pL of an aqueous solution of NaBr (4 mol L' 1 , 108 pmol) and 27 pL of an aqueous solution of NaI (4 mol L' 1 , 108 mmol). The glass reactor is sealed and heated in an aluminum block for 2 hours with stirring at 90 °C.
[0104] After cooling to room temperature, the precipitate is separated by centrifugation in 15 mL centrifuge tubes for 10 minutes at 10,000 rpm. It is then washed twice with water and ethanol and centrifuged again for separation. The colorless precipitate is then dried at room temperature for 12 hours.
[0105] Dye-
[0106] Due to their structure and high positive surface charge, the new compounds [Al24(OH)s6(RCOO)i2]X4 are highly suitable as adsorbents for anions. For example, anionic dyes can be removed quickly and effectively from ethanolic and aqueous solutions by adsorption. Accordingly, the compounds could also be suitable as substrates for the production of pigments.
[0107] 7.2 mg of [Al24(OH)s6(RCOO)i2](HSO4)4 (2 pmol) are dispersed in 1 mL of water. 1 mL of an aqueous colored solution of Alizarin Red S (1 mmol L') is added to the dispersion. 1, 2 pmol) and stirred for 2 hours at room temperature. The red precipitate was separated from the colorless solution by centrifugation in 2 mL centrifuge tubes for 2 minutes at a speed of 9000 rpm. It was then washed twice with water and centrifuged again for separation. The red precipitate was then dried at 50 °C for 12 hours.
[0108] List of figures:
[0109] Figure 1: Structure of the cationic cages, 1a trinuclear building block of composition {Ah(p3-OH)( 2-OH)3} 5+ . Eight of these trinuclear building blocks are linked via 24 OH' and 12 CH3COO- ions (1b), forming a cationic cage of the composition [AI24(OH)56(CH3COO)I2] 4+ is formed (1c).
[0110] Figure 2: Arrangement of the cationic cages in the unit cell (body-centered cubic packing). The edges of the unit cell are shown in black.
[0111] Figure 3: X-ray powder diffractograms of the compounds according to the invention [AI24(OH)56(RCOO)I2]X4 with R = CH3{X = Ch (1), Br (2), h (3), OH' (4), SCN' (5), NO3' (6), HSO4' (7), HS' (8), CIO5' (9), CIO4- (10)}, R = C2H5 {X = CI'} (11) and R = H / CH3 {X = CI} (12), R = - CH2SH {X = CI-}(13)
[0112] Figure 4: X-ray powder diffractograms of the compounds according to the invention [AI24(OH)56(CH3COO)i2]ClyBr4-y with y = 1.3 (14a); 2.3 (14b); 3 (14c).
[0113] Figure 5: X-ray powder diffractograms of the compounds according to the invention [AI24(OH)56(CH3COO)i2]Br x l4-x with x = 3.5 (15a); 3.7 (15b).
[0114] Figure 6: X-ray powder diffractograms of the compound [AI24(OH)56(CH3COO)i2]Cl4 according to the invention prepared under different reaction conditions (reaction temperatures and reaction vessels).
[0115] Figure 7: NMR spectrum of [AI24(OH)56(HCOO)x(CH3COO)i2-x]CI4(12)
Claims
REQUIREMENTS 1. Porous, crystalline compounds according to the following formula: [Al24(OH)56(RCOO)i2]X4, wherein R can be hydrogen or a branched or unbranched, saturated or unsaturated, functionalized or non-functionalized hydrocarbon chain of length from 1 to 8 carbon atoms, and wherein the functionalization is selected from the group consisting of -OH, -F, -CI, -Br, -I, -SH, -NO2, -CHO, -COOH, -SO3H, -NH2, and wherein R can be the same or different, and wherein X can be the same or different, and wherein X is an anion, preferably a monovalent anion, particularly preferably a monovalent anion selected from the group consisting of CI', Br, I; OH; SCN; NO3; HSO4; HS-, CIOs', and CIO4' or mixtures of these anions.
2. Porous, crystalline compound according to claim 1, characterized in that the compound comprises cationic [Al24(OH)s6(RCOO)i2] 4+- contains cages consisting of 8 trinuclear building blocks of composition {A (p3OH)( 2-OH)3} 5+ , 24 OH' and 12 RCOO' ions, with each of the three aluminum cations being Al 3+ octahedrally coordinated by 5 OH' and one RCOO' via the oxygen atom and the {Als(p3-OH)( 2-OH)3} 5+ Building units are arranged on the corners of a cube and adjacent {A (p3-OH)( 2-OH)3} 5+ - Building units are each linked by 2 OH' and 1 RCOO'.
3. Porous, crystalline compound according to claim 2, characterized in that the cationic [Al24(OH)s6(RCOO)i2] 4+ - Cages are arranged in a cubic, center-centered configuration.
4. Porous, crystalline compound according to one of the preceding claims, characterized in that the anions are monovalent anions.
5. Porous, crystalline compound according to claim 4, characterized in that the anions are selected from the group consisting of CI', Br, I; OH; SCN; NO , HSO4; HS; CIO3; and CIO4-. Porous, crystalline compound according to claim 4 or 5, characterized in that monovalent anions occupy 2 / 3 of the octahedrally arranged free sites, which are defined by the body-centered cubic arrangement of the cationic [Al24(OH)s6(RCOO)i2] 4+ - Cages form, occupy. Porous, crystalline compound according to one or more of the preceding claims, characterized in that it is selected from the group [AI24(OH)56(CH3COO)i2]CI4, [AI24(OH)56(CH3COO)i2]Br4, [A^OH CHsCOO^Jk, [AI24(OH)56(CH3COO)i2](OH)4, [Al24(OH)56(CH3COO)i2](SCN)4, [AI24(OH)56(CH3COO)I2](NO3)4, [AI24(OH)56(CH3COO)l2](HSO4)4, [AI24(OH)56(CH3COO)12](HS)4, [AI24(OH)56(CH3COO)12](CIO3)4, [AI24(OH)56(CH3COO)12](CIO4)4, [AI24(OH)56(C2H5COO)12]CI4, [AI24(OH)56(HCOO)x(CH3COO)i2-x]CI4mit x = 1 ; 2, [AI24(OH)56(HSCH2COO)i2]Cl4, [AI24(OH)56(CH3COO)i2]ClyBr4-y mit y = 0 bis 4, [AI24(OH)56(CH3COO)i2]Br yl4-y with y = 0 to 4. A process for the preparation of porous, crystalline compounds according to any one of the preceding claims, comprising the following steps: i. Providing an aqueous solution of an aluminum salt; ii. Adding the carboxylic acid or the mixture of carboxylic acids or their salts; iii. Optionally adding a water-soluble salt of the anion or the mixture of different anions X; iv. Tempering the mixture from step iii at room temperature to 140 °C for 4 weeks to 2 minutes; v. Optionally cooling the mixture to room temperature; vi. Separating the solid from the solution, for example by filtration, spray drying, or centrifugation; vii. Washing the resulting solid with water and / or alcohols; viii. Drying the washed solid. A process according to claim 8, characterized in that the anions X are selected from the group: CI', Br, |-, OH; SCN', NOs', HSO4', HS _, CIOs', and CIÜ4' or mixtures thereof.
10. Use of a porous, crystalline compound according to claims 1 to 7 as an adsorbent for anions.
11. Use of a porous, crystalline compound according to claims 1 to 7 for the adsorption of gases or liquids.
12. Use of a porous, crystalline compound according to claims 1 to 7 for the separation of gases or liquids.
13. Use of a porous, crystalline compound according to claims 1 to 7 as a filler for the production of porous membranes 14. Use of a porous, crystalline compound according to claims 1 to 7 as a coating material 15. Use of a porous, crystalline compound according to claims 1 to 7 for the production of aluminium oxides or aluminium hydroxides.
16. Use of a porous, crystalline compound according to claims 1 to 7 for the preparation of metal-organic framework compounds.