A method for preparing a zirconium-based metal-organic framework material by using a non-volatile organic carboxylate salt and a zirconium-based metal-organic framework material

Abstract

The application discloses a kind of non-volatile organic carboxylate salt adjustment preparation zirconium-based metal organic framework material and zirconium-based metal organic framework material, belong to nanometer material preparation technical field, including the following steps: zirconium source is dissolved in water, stirring is uniform, obtains zirconium source aqueous system;Organic polycarboxylic acid ligand is added to water, then non-volatile organic carboxylate salt regulator is added, mixed uniformly, obtains ligand-regulator aqueous system, then with zirconium source aqueous system mixed uniformly, and carry out crystallization reaction and cooling, obtain zirconium-based metal organic framework material slurry;Zirconium-based metal organic framework material slurry is carried out solid-liquid separation, then sequentially through washing, drying and vacuum activation, obtain zirconium-based metal organic framework material.The application has the advantages of raw material easy to obtain, low waste liquid burden, easy to scale-up preparation, etc., is conducive to the green synthesis and industrialization of zirconium-based metal organic framework material.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of nanomaterial preparation, and particularly relates to a method for preparing a zirconium-based metal organic framework material by using a non-volatile organic carboxylate salt as a regulator and the zirconium-based metal organic framework material. BACKGROUND

[0002] Metal-organic frameworks (MOFs) are a kind of crystalline porous materials formed by connecting metal ions or metal clusters with organic ligands through coordination bonds, and have characteristics such as a designable pore structure, a tunable composition and abundant functional sites, and have shown application potential in fields such as gas adsorption and separation, water vapor adsorption, catalysis, sensing and environmental governance.

[0003] Zirconium-based metal organic framework materials are usually constructed by connecting zirconium-oxygen clusters formed by hydrolysis of Zr(IV) ions with polycarboxylic acid organic ligands, and representative materials include MOF-801 using fumaric acid as a ligand, UiO series using terephthalic acid, 4,4'-biphenyldicarboxylic acid and functional derivatives thereof as ligands, and MOF-808 using trimesic acid as a ligand. The above-mentioned materials have high chemical stability, tunable pore structure and abundant node coordination sites, and have application value in fields such as water vapor adsorption, gas adsorption and separation, pollutant adsorption and catalysis. The ligand structures and node connection modes used by different zirconium-based MOFs are different, but the aqueous phase crystallization process thereof involves processes such as hydrolysis of a zirconium source, generation of a zirconium-oxygen cluster, deprotonation of an organic ligand, coordination competition, formation of a crystal nucleus and crystal growth.

[0004] Traditional zirconium-based MOFs are usually synthesized in organic solvents such as N,N-dimethylformamide (DMF), and free carboxylic acids such as formic acid and acetic acid are used as regulators to control the formation of zirconium-oxygen clusters, crystal nucleation and growth by competition between carboxylate and zirconium species. Free acids such as formic acid and acetic acid have high volatility, and can easily cause fluctuations in the actual amount of the regulator added and the composition of the system during feeding, temperature rising, temperature maintaining and refluxing; in the process of scale-up preparation, it also increases the burden of collecting volatile acidic components, tail gas treatment and material balance control. SUMMARY

[0005] The present application aims to overcome the deficiencies in the prior art, and provides a method for preparing a zirconium-based metal organic framework material by using a non-volatile organic carboxylate salt as a regulator and the zirconium-based metal organic framework material. In the present application, water is used as a reaction medium, a zirconium source and an organic polycarboxylic acid ligand are used as raw materials, and a non-volatile organic carboxylate salt is used to regulate the competition between zirconium-oxygen clusters and ligands and the crystal growth process, a water-phase regulation synthesis route for different zirconium-based metal organic framework materials is designed, the use of organic solvents such as DMF and volatile free acid regulators is reduced or avoided, and a green water-phase preparation route suitable for 1-10 L tank reactors is formed.

[0006] This invention provides the following technical solution:

[0007] In a first aspect, a method for preparing zirconium-based metal-organic framework materials by regulating the use of non-volatile organic carboxylates is provided, comprising the following steps:

[0008] The zirconium source was dissolved in water and stirred until homogeneous to obtain an aqueous zirconium source system.

[0009] Based on zirconium-based metal-organic framework materials, organic polycarboxylic acid ligands were determined, and the organic polycarboxylic acid ligands were added to water. Then, non-volatile organic carboxylic acid salt regulators were added and mixed evenly to obtain a ligand-regulator aqueous phase system.

[0010] The zirconium source aqueous system and the ligand-modifier aqueous system were mixed evenly and crystallization reaction was carried out in the aqueous phase. Then, the mixture was cooled to room temperature to obtain a zirconium-based metal-organic framework material slurry.

[0011] The zirconium-based metal-organic framework material slurry was subjected to solid-liquid separation, followed by washing, drying and vacuum activation to obtain the zirconium-based metal-organic framework material.

[0012] Furthermore, the zirconium source includes one or more of zirconium dichloride octahydrate, zirconium oxynitrate, zirconium nitrate, zirconium sulfate, zirconium acetate, or their hydrates, preferably one of zirconium dichloride octahydrate, zirconium oxynitrate, and zirconium nitrate.

[0013] Furthermore, the zirconium-based metal-organic framework material includes one of MOF-801, UiO-66, UiO-66-NH2, UiO-67, UiO-68, MOF-808, MOF-545 (PCN-222), PCN-224, NU-1000, NU-901, DUT-67, DUT-68, DUT-69, MIP-202 (Zr), and MIP-206. Preferably, the zirconium-based metal-organic framework material is one of MOF-801, UiO-66, UiO-66-NH2, UiO-67, and MOF-808.

[0014] Furthermore, the organic polycarboxylic acid ligand includes one of fumaric acid, 2-aminoterephthalic acid, 1,2,4,5-benzenetetracarboxylic acid, phthalic acid, 4,4′-biphenyldicarboxylic acid, and pyromellitic acid.

[0015] Furthermore, the organic carboxylic acid in the non-volatile organic carboxylic acid salt regulator includes one or more of aromatic carboxylic acids, substituted aromatic carboxylic acids, aliphatic monocarboxylic acids, aliphatic polycarboxylic acids, hydroxycarboxylic acids, aminocarboxylic acids, and heterocyclic carboxylic acids.

[0016] Furthermore, the cations in the non-volatile organic carboxylate regulator include one or more of alkali metal ions, alkaline earth metal ions, and ammonium ions, preferably sodium ions or potassium ions.

[0017] Furthermore, the solubility of the free organic carboxylic acid corresponding to the non-volatile organic carboxylic acid salt regulator in water at 25°C is not higher than 5 g / L, preferably not higher than 1 g / L.

[0018] Furthermore, the non-volatile organic carboxylate modifier includes sodium benzoate, disodium terephthalate, sodium pyridine-2-carboxylate, sodium acetate, sodium dihydrogen citrate, disodium succinate, sodium o-chlorobenzoate, sodium m-chlorobenzoate, sodium p-chlorobenzoate, sodium o-bromobenzoate, sodium m-bromobenzoate, sodium p-bromobenzoate, sodium o-methylbenzoate, sodium m-methylbenzoate, sodium p-methylbenzoate, sodium dichlorobenzoate, and dibromobenzoic acid. Sodium, sodium dimethylbenzoate, sodium fluorobenzoate, sodium iodobenzoate, sodium hydroxybenzoate, sodium methoxybenzoate, sodium citrate, trisodium citrate dihydrate, sodium malate, sodium tartrate, sodium oxalate, sodium malonate, sodium succinate, sodium glutarate, sodium adipate, sodium decanoate, sodium gluconate, sodium glycolate, sodium lactate, sodium salicylate, sodium nicotinate, sodium pyridinecarboxylate, sodium p-toluenesulfonate, sodium phenylphosphonate.

[0019] Furthermore, when the zirconium-based metal-organic framework material is MOF-801, UiO-66-NH2, UiO-66 or UiO-67, the molar ratio of zirconium, the organic polycarboxylic acid ligand and the non-volatile organic carboxylic acid salt regulator in the zirconium source is 1:(0.5~2.0):(0.1~20), preferably 1:(0.8~1.2):(1~10).

[0020] Furthermore, when the zirconium-based metal-organic framework material is MOF-808, the molar ratio of zirconium, the organic polycarboxylic acid ligand and the non-volatile organic carboxylic acid salt regulator in the zirconium source is 1:(0.2~0.6):(0.1~20).

[0021] Furthermore, the concentration of zirconium in the zirconium source is 0.01~1 mol / L.

[0022] Furthermore, when the zirconium-based metal-organic framework material is either MOF-801 or UiO-66-NH2, the preparation of the ligand-modifier aqueous system includes:

[0023] At a temperature of 20~100℃, organic polycarboxylic acid ligands are added to water, followed by the addition of non-volatile organic carboxylic acid salt regulators. The mixture is stirred or dispersed for 10~120 min until homogeneous, thus obtaining a ligand-regulator aqueous phase system.

[0024] Furthermore, when the zirconium-based metal-organic framework material is any one of UiO-66, UiO-67, and MOF-808, the preparation of the ligand-modifier aqueous system further includes deprotonation treatment, including:

[0025] At a temperature of 20~100℃, organic polycarboxylic acid ligands are added to water, followed by deprotonation treatment with 0.1~4 mol / L sodium hydroxide aqueous solution. Then, non-volatile organic carboxylic acid salt regulators are added, and the mixture is stirred or dispersed for 10~120 min until homogeneous to obtain a ligand-regulator aqueous phase system.

[0026] Furthermore, when the zirconium-based metal-organic framework material is UiO-66, the organic polycarboxylic acid ligand is terephthalic acid, and the molar ratio of sodium hydroxide to terephthalic acid is (0.5~2.0):1.

[0027] Furthermore, when the zirconium-based metal-organic framework material is UiO-67, the organic polycarboxylic acid ligand is 4,4′-biphenyldicarboxylic acid, and the molar ratio of sodium hydroxide to 4,4′-biphenyldicarboxylic acid is (1.0~2.0):1.

[0028] Furthermore, when the zirconium-based metal-organic framework material is MOF-808, the organic polycarboxylic acid ligand is trimesic acid, and the molar ratio of sodium hydroxide to trimesic acid is (1.0~3.0):1.

[0029] Furthermore, the zirconium source aqueous system is mixed with the ligand-modifier aqueous system and stirred at 50~500 rpm for 10~120 min. After the mixture is homogeneous, a crystallization reaction is carried out at a temperature of 60~140℃ for 2~48 h. After the reaction is completed, the mixture is cooled to room temperature to obtain a zirconium-based metal-organic framework material slurry.

[0030] Furthermore, the crystallization reaction is carried out in a sealed reaction vessel;

[0031] Alternatively, the crystallization reaction is carried out in a batch reactor with a total volume of 1 to 10 L and equipped with mechanical stirring, jacket temperature control, and reflux condensation device, with a reflux temperature of 95 to 105 °C and a reflux reaction time of 6 to 30 h.

[0032] Furthermore, the zirconium-based metal-organic framework material slurry is subjected to solid-liquid separation by vacuum filtration, pressure filtration, or centrifugation at 3000~10000 rpm for 5~30 min. It is then washed with water and ethanol 1~5 times in sequence, dried at 60~120℃ for 6~24 h, and vacuum activated at 80~200℃ for 4~24 h to obtain the zirconium-based metal-organic framework material.

[0033] In a second aspect, a zirconium-based metal-organic framework material is prepared by the method for preparing zirconium-based metal-organic framework materials according to any one of the first aspects using non-volatile organic carboxylates.

[0034] Compared with the prior art, the beneficial effects of the present invention are:

[0035] (1) This invention uses zirconium source as raw material, organic polycarboxylic acid ligand, non-volatile organic carboxylic acid salt regulator and water to construct a unified aqueous crystallization system. The non-volatile organic carboxylic acid salt is used as a source of carboxylic acid and a competitive coordination regulator, which can maintain the carboxylic acid effect required for zirconium species coordination regulation and crystal growth control. For regulators with low water solubility of corresponding free carboxylic acid, salt formation can improve their solubility or dispersion in the aqueous phase, so that the regulator participates in the zirconium species coordination and crystallization process in a more uniform state, further expanding the scope of application of regulators under pure aqueous phase conditions.

[0036] (2) Non-volatile organic carboxylates can be added quantitatively in the form of stable solids or aqueous solutions. They have a relatively stable material composition during heating, crystallization and reflux, which is beneficial for controlling the actual amount of regulator added, the ratio of reactants and the consistency of processes between batches.

[0037] (3) The present invention uses water as a crystallization medium and a salt-type regulator to form a preparation system with low organic solvent load and low volatile acid load, thereby reducing the collection of volatile acid components and tail gas treatment pressure, and is compatible with the batch scale-up process of mechanical stirring, jacket temperature control and condensation reflux.

[0038] (4) Non-volatile organic carboxylates have a rich variety of structural types. Different carboxyl group structures can be selected according to the ligand composition and crystallization conditions of the target zirconium-based MOF, expanding the range of regulators that can be selected for the traditional formic acid and acetic acid regulation system, and are applicable to the aqueous phase preparation of various zirconium-based MOFs. Attached Figure Description

[0039] Figure 1 The PXRD patterns and simulated XRD patterns of MOF-801 material in Examples 1, 3-8 of this invention are shown.

[0040] Figure 2 The nitrogen adsorption isotherm of MOF-801 material in Examples 1, 3-8 of this invention at 77K.

[0041] Figure 3 These are the PXRD patterns of the samples prepared in Examples 11-15 of this invention and the simulated XRD patterns of the corresponding target zirconium-based MOFs;

[0042] Figure 4 These are the nitrogen adsorption isotherms of the samples prepared in Examples 11-15 of this invention at 77 K.

[0043] Figure 5 These are the PXRD patterns of the samples prepared in Comparative Examples 1-6 of this invention and the simulated XRD patterns of the corresponding target zirconium-based MOFs;

[0044] Figure 6 These are the nitrogen adsorption isotherms of the samples prepared in Comparative Examples 1-6 of this invention at 77 K. Detailed Implementation

[0045] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0046] In the description of this invention, unless otherwise stated, "a plurality of" or "multiple" means two or more. The terms "comprising," "including," "having," "containing," etc., as used herein are open-ended, meaning they include but are not limited to.

[0047] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0048] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0049] This invention provides a method for preparing zirconium-based metal-organic framework materials by regulating the use of non-volatile organic carboxylates, comprising the following steps.

[0050] S1. Add the zirconium source to deionized water, stir to dissolve or disperse evenly to obtain a zirconium source aqueous phase system.

[0051] In one possible embodiment, the zirconium source includes any one or more of zirconium oxychloride octahydrate (ZrOCl2·8H2O), zirconium oxynitrate, zirconium nitrate, zirconium sulfate, zirconium acetate, or their hydrates, preferably a zirconium source capable of forming a homogeneous system in water, such as zirconium oxychloride octahydrate, zirconium oxynitrate, or zirconium sulfate.

[0052] S2. Determine the organic polycarboxylic acid ligand based on the target zirconium-based metal-organic framework material. Add the organic polycarboxylic acid ligand to water at a temperature of 20~100℃, then add a non-volatile organic carboxylic acid salt regulator, stir or assist dispersion for 10~120 min, mix evenly, and obtain the ligand-regulator aqueous phase system.

[0053] The organic polycarboxylic acid ligands were determined based on the target zirconium-based metal-organic framework material.

[0054] When the zirconium-based metal-organic framework material is MOF-801, the organic polycarboxylic acid ligand is fumaric acid.

[0055] When the zirconium-based metal-organic framework material is UiO-66, the organic polycarboxylic acid ligand is terephthalic acid.

[0056] When the zirconium-based metal-organic framework material is UiO-66-NH2, the organic polycarboxylic acid ligand is 2-aminoterephthalic acid.

[0057] When the zirconium-based metal-organic framework material is UiO-66-(COOH)2, the organic polycarboxylic acid ligand is 1,2,4,5-benzenetetracarboxylic acid.

[0058] When the zirconium-based metal-organic framework material is UiO-67, the organic polycarboxylic acid ligand is 4,4′-biphenyldicarboxylic acid.

[0059] When the zirconium-based metal-organic framework material is MOF-808, the organic polycarboxylic acid ligand is pyromellitic acid.

[0060] In one possible embodiment, when the zirconium-based metal-organic framework material is any one of UiO-66, UiO-67, and MOF-808, the preparation of the ligand-modifier aqueous system further includes a deprotonation process. Specifically, this includes the following steps: At a temperature of 20–100°C, the organic polycarboxylic acid ligand is added to water, followed by the addition of a 0.1–4 mol / L sodium hydroxide aqueous solution for deprotonation treatment. Then, a non-volatile organic carboxylic acid salt modifier is added, and the mixture is stirred or assisted in dispersion for 10–120 min until homogeneous, thus obtaining the ligand-modifier aqueous system.

[0061] Specifically, when the zirconium-based metal-organic framework material is UiO-66, the molar ratio of sodium hydroxide to terephthalic acid is (0.5~2.0):1. When the zirconium-based metal-organic framework material is UiO-67, the molar ratio of sodium hydroxide to 4,4′-biphenyl dicarboxylic acid is (1.0~2.0):1. When the zirconium-based metal-organic framework material is MOF-808, the molar ratio of sodium hydroxide to trimesic acid is (1.0~3.0):1.

[0062] In one possible embodiment, the non-volatile organic carboxylic acid in the non-volatile organic carboxylic acid salt regulator includes any one or more of aromatic carboxylic acids, substituted aromatic carboxylic acids, aliphatic monocarboxylic acids, aliphatic polycarboxylic acids, hydroxycarboxylic acids, aminocarboxylic acids, and heterocyclic carboxylic acids. Preferably, it employs any one or more of aromatic monocarboxylic acids, substituted aromatic monocarboxylic acids, aliphatic monocarboxylic acids, aliphatic polycarboxylic acids, hydroxycarboxylic acids, aminocarboxylic acids, and heterocyclic carboxylic acids.

[0063] In one possible embodiment, the salt-forming cation in the non-volatile organic carboxylate regulator includes one or more of alkali metal ions, alkaline earth metal ions, and ammonium ions, preferably sodium ions or potassium ions.

[0064] Non-volatile organic carboxylate regulators specifically include any one or more of the following: sodium benzoate, disodium terephthalate, sodium pyridine-2-carboxylate, sodium acetate, sodium dihydrogen citrate, disodium succinate, sodium o-chlorobenzoate, sodium m-chlorobenzoate, sodium p-chlorobenzoate, sodium o-bromobenzoate, sodium m-bromobenzoate, sodium p-bromobenzoate, sodium o-methylbenzoate, sodium m-methylbenzoate, sodium p-methylbenzoate, sodium dichlorobenzoate, sodium dibromobenzoate, sodium dimethylbenzoate, sodium fluorobenzoate, sodium iodobenzoate, sodium hydroxybenzoate, sodium methoxybenzoate, sodium citrate, trisodium citrate dihydrate, sodium malate, sodium tartrate, sodium oxalate, sodium malonate, sodium succinate, sodium glutarate, sodium adipate, sodium decanoate, sodium gluconate, sodium glycolate, sodium lactate, sodium salicylate, sodium nicotinic acid, or sodium pyridinecarboxylate.

[0065] Furthermore, the solubility of the free organic carboxylic acid corresponding to the non-volatile organic carboxylic acid salt regulator in water at 25°C is not higher than 5 g / L, preferably not higher than 1 g / L; the corresponding organic carboxylic acid salt can form a homogeneous aqueous phase system under the preparation conditions of the ligand-regulator aqueous phase system.

[0066] S3. Mix the zirconium source aqueous system with the ligand-modifier aqueous system, stirring at 50-500 rpm for 10-120 min until homogeneous, ensuring full contact between the zirconium source, organic polycarboxylic acid ligand, and non-volatile organic carboxylic acid salt modifier. Place the mixture in a sealed reaction vessel, a heatable reaction container, or a batch reactor with a reflux condenser, using water as the sole solvent, and crystallize at 60-140℃ for 2-48 h. Small-scale laboratory tests can be conducted in a closed reaction vessel; scale-up preparation can be carried out in a batch reactor with mechanical stirring, jacketed temperature control, and a reflux condenser at 95-105℃ for 6-30 h, with a reaction volume of 1-10 L and a stirring speed of 50-500 rpm. After the reaction is complete, cool to obtain a zirconium-based metal-organic framework material slurry.

[0067] In one possible embodiment, when the zirconium-based metal-organic framework material is MOF-801, UiO-66, UiO-66-NH2, UiO-66-(COOH)2, or UiO-67, the molar ratio of zirconium, organic polycarboxylic acid ligand, and non-volatile organic carboxylic acid salt modifier in the zirconium source is 1:(0.5~2.0):(0.1~20), preferably 1:(0.8~1.2):(1~10). When the zirconium-based metal-organic framework material is MOF-808, the molar ratio of zirconium source, organic polycarboxylic acid ligand, and non-volatile organic carboxylic acid salt modifier is 1:(0.2~0.6):(0.1~20).

[0068] The concentration of zirconium in the reaction system is 0.01~1 mol / L.

[0069] S4. The zirconium-based metal-organic framework material slurry is filtered, pressure filtered, or centrifuged to obtain a solid. When centrifuging, the centrifugation speed is 3000~10000 rpm, and the centrifugation time is 5~30 min. The obtained solid is first washed with water to remove soluble inorganic salts, unreacted zirconium sources, and free ligands, and then washed with ethanol to replace residual moisture and organic residues between particles and in the pores. Water washing and ethanol washing are performed 1~5 times each. Then, it is dried at 60~120℃ for 6~24 h and activated under vacuum at 80~200℃ for 4~24 h to obtain the zirconium-based metal-organic framework material.

[0070] This invention employs non-volatile organic carboxylates as a source of carboxylate and a competing coordination modifier, providing a low-volatility and easily measurable alternative to traditional free small-molecule carboxylic acid regulation systems such as formic acid and acetic acid. It also reduces the operational and exhaust gas treatment burden associated with the direct addition of volatile free acids. Non-volatile organic carboxylates exhibit a relatively stable material composition during feeding, heating, and crystallization, which is beneficial for controlling the reactant ratio and batch consistency. For organic carboxylic acids with low water solubility, such as benzoic acid and its substituted derivatives, and medium- and long-chain aliphatic carboxylic acids, salt formation can further improve their solubility or dispersion in the aqueous phase, allowing the modifier to participate more uniformly in the coordination and crystallization process of zirconium species. Therefore, using non-volatile organic carboxylates as modifiers to construct an aqueous zirconium-based MOF preparation method improves the controllability of the process composition and is suitable for batch-scale preparation.

[0071] Example 1

[0072] In a 2 L glass batch reactor equipped with a mechanical stirrer, jacketed heating, and reflux condenser, 400 mL of deionized water was added, along with 16.11 g (50 mmol, as Zr) of zirconium oxychloride octahydrate. The mixture was stirred at room temperature until dissolved to obtain an aqueous zirconium source system. Separately, 600 mL of deionized water was added to a beaker, along with 5.8 g (50 mmol) of fumaric acid and 44.12 g (150 mmol) of trisodium citrate dihydrate. The mixture was stirred until a ligand-modifier aqueous system was formed, and then added to the batch reactor described above.

[0073] The total volume of the reaction system was adjusted to 1 L, and mechanical stirring was started at 300 rpm. Mixing was carried out at room temperature for 30 min. The molar ratio of zirconium (calculated as Zr), fumaric acid, and trisodium citrate dihydrate in this system was 1:1:3; the Zr concentration was 0.05 mol / L, the fumaric acid concentration was 0.05 mol / L, and the trisodium citrate dihydrate concentration was 0.15 mol / L. The mixture was then heated to reflux using a jacket, with the system temperature controlled at 98–100 °C. The mixture was refluxed and stirred for 18 h. After the reaction was complete, heating was stopped, and stirring was continued while cooling to room temperature to obtain MOF-801 slurry. This slurry was then washed three times with deionized water and twice with ethanol, dried at 80 °C for 12 h, and then activated under vacuum at 120 °C for 6 h to obtain powdered MOF-801 material.

[0074] Example 2

[0075] 92.9 mg (0.8 mmol) of fumaric acid and 2941 mg (10 mmol) of trisodium citrate dihydrate were added to deionized water to obtain a ligand-modifier aqueous system. This system was then mixed with 322.2 mg (1 mmol) of zirconium oxychloride octahydrate to form a 20 mL reaction system. The molar ratio of zirconium (calculated as Zr), fumaric acid, and trisodium citrate dihydrate in this system was 1:0.8:10; the Zr concentration was 0.05 mol / L, the fumaric acid concentration was 0.04 mol / L, and the trisodium citrate dihydrate concentration was 0.5 mol / L.

[0076] The above system was transferred to a 50 mL polytetrafluoroethylene-lined reactor and reacted at 110 °C for 18 h. After the reaction was completed, heating was stopped and stirring was continued. After cooling to room temperature, MOF-801 slurry was obtained.

[0077] After being filtered, the MOF-801 slurry was washed three times with deionized water and twice with ethanol, dried at 80℃ for 12 h, and then activated under vacuum at 120℃ for 6 h to obtain powdered MOF-801 material.

[0078] Example 3

[0079] Weigh 322.2 mg (1 mmol) of zirconium oxychloride octahydrate and add it to 4.0 mL of deionized water. Stir and dissolve to obtain a zirconium source aqueous phase system. Separately weigh 116.1 mg (1 mmol) of fumaric acid and 890.3 mg (5 mmol) of disodium malate and add them to 6 mL of deionized water. Stir for 20 min to form a uniformly dispersed ligand-modifier aqueous phase system.

[0080] The zirconium source aqueous system and the ligand-modifier aqueous system were mixed and stirred for 30 min before being transferred to a 25 mL polytetrafluoroethylene-lined reactor. The molar ratio of zirconium (calculated as Zr), fumaric acid, and disodium malate in this system was 1:1:5; based on a total volume of 10 mL after mixing, the Zr concentration was 0.1 mol / L, the fumaric acid concentration was 0.1 mol / L, and the disodium malate concentration was 0.5 mol / L. The reactor was placed in a 105℃ oven for crystallization reaction for 18 h. After the reaction was completed, it was cooled to room temperature to obtain MOF-801 slurry.

[0081] After being filtered, the MOF-801 slurry was washed three times with deionized water and twice with ethanol, dried at 80℃ for 12 h, and then activated under vacuum at 120℃ for 6 h to obtain powdered MOF-801 material.

[0082] Example 4

[0083] Weigh 322.2 mg (1 mmol, calculated as Zr) of zirconium oxychloride octahydrate and add it to 5 mL of deionized water. Stir and dissolve to obtain the zirconium source aqueous phase system. Separately weigh 139.3 mg (1.2 mmol) of fumaric acid and 872.6 mg (4 mmol) of sodium gluconate and add them to 7 mL of deionized water. Stir and sonicate for 15 min to obtain the ligand-modifier aqueous phase system.

[0084] The zirconium source aqueous system and the ligand-modifier aqueous system were mixed and stirred at room temperature for 30 min, then transferred to a 25 mL polytetrafluoroethylene-lined reactor. The molar ratio of zirconium (calculated as Zr), fumaric acid, and sodium gluconate in this system was 1:1.2:4; based on a total volume of 12 mL after mixing, the Zr concentration was 0.083 mol / L, the fumaric acid concentration was 0.1 mol / L, and the sodium gluconate concentration was 0.333 mol / L. The reactor was placed in a 110 °C oven for crystallization reaction for 16 h. After the reaction was completed, it was cooled to room temperature to obtain MOF-801 slurry.

[0085] After being filtered, the MOF-801 slurry was washed three times with deionized water and twice with ethanol, dried at 80℃ for 12 h, and then activated under vacuum at 120℃ for 6 h to obtain powdered MOF-801 material.

[0086] Example 5

[0087] Weigh 322.2 mg (1 mmol) of zirconium oxychloride octahydrate and add it to 5 mL of deionized water. Stir and dissolve to obtain the zirconium source aqueous phase system. Separately weigh 92.9 mg (0.8 mmol) of fumaric acid and 268 mg (2 mmol) of sodium oxalate and add them to 5 mL of deionized water. Stir for 20 min and mix thoroughly to obtain the ligand-modifier aqueous phase system.

[0088] The zirconium source aqueous system and the ligand-modifier aqueous system were mixed and stirred at room temperature for 30 min, then transferred to a 25 mL polytetrafluoroethylene-lined reactor. The molar ratio of zirconium (calculated as Zr), fumaric acid, and sodium oxalate in this system was 1:0.8:2; based on a total volume of 10 mL after mixing, the Zr concentration was 0.1 mol / L, the fumaric acid concentration was 0.08 mol / L, and the sodium oxalate concentration was 0.2 mol / L. The reactor was placed in a 100 °C oven for crystallization reaction for 20 h. After the reaction was completed, it was cooled to room temperature to obtain MOF-801 slurry.

[0089] After being filtered, the MOF-801 slurry was washed three times with deionized water and twice with ethanol, dried at 80℃ for 12 h, and then activated under vacuum at 120℃ for 6 h to obtain powdered MOF-801 material.

[0090] Example 6

[0091] 322.2 mg (1 mmol) of zirconium oxychloride octahydrate was weighed and dissolved in 8 mL of deionized water to obtain a zirconium source aqueous phase system. Separately, 116.1 mg (1 mmol) of fumaric acid and 194.3 mg (1 mmol) of sodium decanoate were weighed and added to 12 mL of deionized water. The mixture was stirred at 60 °C for 30 min and sonicated for 10 min until homogeneous to obtain a ligand-modifier aqueous phase system.

[0092] The zirconium source aqueous system and the ligand-modifier aqueous system were mixed and stirred at room temperature for 30 min, then transferred to a 50 mL polytetrafluoroethylene-lined reactor. The molar ratio of zirconium (calculated as Zr), fumaric acid, and sodium decanoate in this system was 1:1:1; based on a total volume of 20 mL after mixing, the concentrations of Zr, fumaric acid, and sodium decanoate were 0.05 mol / L. The reactor was placed in a 120℃ oven for crystallization reaction for 24 h. After the reaction was completed, it was cooled to room temperature to obtain MOF-801 slurry.

[0093] After being filtered, the MOF-801 slurry was washed three times with deionized water and twice with ethanol, dried at 80℃ for 12 h, and then activated under vacuum at 120℃ for 6 h to obtain powdered MOF-801 material.

[0094] Example 7

[0095] Weigh 322.2 mg (1 mmol, calculated as Zr) of zirconium oxychloride octahydrate and add it to 6 mL of deionized water. Stir and dissolve to obtain a zirconium source aqueous phase system. Separately weigh 116.1 mg (1 mmol) of fumaric acid and 315.1 mg (1.5 mmol) of disodium terephthalate and add them to 9 mL of deionized water. Stir and sonicate for 20 min to form a ligand-modifier aqueous phase system.

[0096] The zirconium source aqueous system and the ligand-modifier aqueous system were mixed and stirred at room temperature for 30 min, then transferred to a 25 mL polytetrafluoroethylene-lined reactor. The molar ratio of zirconium (calculated as Zr), fumaric acid, and disodium terephthalate in this system was 1:1.0:1.5; based on a total volume of 15.0 mL after mixing, the Zr concentration was 0.067 mol / L, the fumaric acid concentration was 0.067 mol / L, and the disodium terephthalate concentration was 0.1 mol / L. The reactor was placed in a 120 ℃ oven for crystallization reaction for 20 h. After the reaction was completed, it was cooled to room temperature to obtain MOF-801 slurry.

[0097] After being filtered, the MOF-801 slurry was washed three times with deionized water and twice with ethanol, dried at 80℃ for 12 h, and then activated under vacuum at 120℃ for 6 h to obtain powdered MOF-801 material.

[0098] Example 8

[0099] Weigh 322.2 mg (1 mmol) of zirconium oxychloride octahydrate and add it to 5 mL of deionized water. Stir and dissolve to obtain the zirconium source aqueous phase system. Separately weigh 116.1 mg (1 mmol) of fumaric acid and 290.2 mg (2 mmol) of sodium pyridine-2-carboxylate and add them to 5 mL of deionized water. Stir for 20 min and mix thoroughly to obtain the ligand-modifier aqueous phase system.

[0100] The zirconium source aqueous system and the ligand-modifier aqueous system were mixed and stirred at room temperature for 30 min, then transferred to a 25 mL polytetrafluoroethylene-lined reactor. The molar ratio of zirconium (calculated as Zr), fumaric acid, and sodium pyridine-2-carboxylate in this system was 1:1:2; based on a total volume of 10 mL after mixing, the Zr concentration was 0.1 mol / L, the fumaric acid concentration was 0.1 mol / L, and the sodium pyridine-2-carboxylate concentration was 0.2 mol / L. The reactor was placed in a 105 ℃ oven for crystallization reaction for 18 h. After the reaction was completed, it was cooled to room temperature to obtain MOF-801 slurry.

[0101] After being filtered, the MOF-801 slurry was washed three times with deionized water and twice with ethanol, dried at 80℃ for 12 h, and then activated under vacuum at 120℃ for 6 h to obtain powdered MOF-801 material.

[0102] Example 9

[0103] 322.2 mg (1 mmol) of zirconium oxychloride octahydrate was weighed and dissolved in 5 mL of deionized water by stirring to obtain a zirconium source aqueous phase system. Separately, 116.1 mg (1 mmol) of fumaric acid, 882.3 mg (3 mmol) of trisodium citrate dihydrate, and 534.2 mg (3 mmol) of disodium malate were weighed and dissolved in 7 mL of deionized water, stirred, and sonicated for 15 min to form a compound regulator, thus obtaining a ligand-regulator aqueous phase system.

[0104] The zirconium source aqueous system and the ligand-modifier aqueous system were mixed and stirred at room temperature for 30 min, then transferred to a 25 mL polytetrafluoroethylene-lined reactor. The molar ratio of zirconium (calculated as Zr), fumaric acid, trisodium citrate dihydrate, and disodium malate in this system was 1:1:3:3. Based on a total volume of 12 mL after mixing, the Zr concentration was 0.083 mol / L, the fumaric acid concentration was 0.083 mol / L, and the total modifier concentration was 0.5 mol / L. The reactor was placed in a 110℃ oven for crystallization reaction for 18 h. After the reaction was completed, it was cooled to room temperature to obtain MOF-801 slurry.

[0105] After being filtered, the MOF-801 slurry was washed three times with deionized water and twice with ethanol, dried at 80℃ for 12 h, and then activated under vacuum at 120℃ for 6 h to obtain powdered MOF-801 material.

[0106] Example 10

[0107] In a 10 L batch reactor equipped with an anchor-type or propeller-type agitator, jacketed temperature control, and reflux condenser, 2 L of deionized water was added, followed by 64.45 g (200 mmol) of zirconium oxychloride octahydrate. The mixture was stirred and dissolved to obtain a zirconium source aqueous phase system. Separately, 18.57 g (160 mmol) of fumaric acid and 53.6 g (400 mmol) of sodium oxalate were added to 3 L of deionized water and dispersed by stirring to obtain a ligand-modifier aqueous phase system, which was then added to the batch reactor.

[0108] The total volume of the mixed reaction system was 5 L. The stirring speed was controlled at 250 rpm, and the mixture was stirred at room temperature for 40 min. The molar ratio of zirconium (calculated as Zr), fumaric acid, and sodium oxalate in the system was 1:0.8:2; the Zr concentration was 0.04 mol / L, the fumaric acid concentration was 0.032 mol / L, and the sodium oxalate concentration was 0.08 mol / L. The system was then heated to reflux, with the liquid phase temperature controlled at 98~100℃. The reaction was carried out under reflux and stirring for 20 h. During the reaction, the liquid level was kept stable by condensation and reflux. After the reaction was completed, the mixture was cooled to room temperature to obtain MOF-801 slurry.

[0109] After being filtered, the MOF-801 slurry was washed three times with deionized water and twice with ethanol, dried at 80℃ for 12 h, and then activated under vacuum at 120℃ for 6 h to obtain powdered MOF-801 material.

[0110] Example 11

[0111] Weigh 322.2 mg (1 mmol, calculated as Zr) of zirconium oxychloride octahydrate and add it to 5 mL of deionized water. Stir at room temperature until dissolved to obtain the zirconium source aqueous phase system. Separately weigh 166.1 mg (1 mmol) of terephthalic acid and add it to 5 mL of deionized water. Under stirring, add 1.5 mL (1.5 mmol) of 1.0 mol / L sodium hydroxide aqueous solution dropwise over 20 min, then stir at 60 °C for 30 min to obtain the terephthalate aqueous phase system. Weigh 474.4 mg (3 mmol) of sodium p-toluene and dissolve it in 3.5 mL of deionized water. Add this to the above ligand aqueous phase system and continue stirring for 20 min to obtain the ligand-modifier aqueous phase system.

[0112] The ligand-modifier aqueous system was added to the zirconium source aqueous system within 30 min, and stirred at 300 rpm for 30 min at room temperature. Deionized water was then added to bring the total volume of the reaction system to 15 mL. The molar ratio of zirconium (calculated as Zr), terephthalic acid, and sodium p-methylbenzoate in this system was 1:1:3, and the Zr concentration was 0.067 mol / L. The mixture was transferred to a 25 mL polytetrafluoroethylene-lined reactor and crystallized at 100 °C for 18 h. After cooling to room temperature, a white slurry was obtained. The slurry was filtered, and the resulting solid was washed three times with deionized water (20 mL each time) and twice with ethanol (20 mL each time). It was dried at 80 °C for 12 h and then activated under vacuum at 120 °C for 6 h to obtain a powdered UiO-66 sample.

[0113] Example 12

[0114] 322.2 mg (1 mmol, calculated as Zr) of zirconium oxychloride octahydrate was weighed and dissolved in 5 mL of deionized water by stirring to obtain a zirconium source aqueous phase system. Separately, 181.1 mg (1 mmol) of 2-aminoterephthalic acid and 410.2 mg (5 mmol) of sodium acetate were weighed and added to 10 mL of deionized water. The mixture was stirred at 60 °C for 30 min and then sonicated for 10 min to obtain a uniformly dispersed ligand-modifier aqueous phase system.

[0115] The zirconium source aqueous system was added to the ligand-modifier aqueous system and stirred at 300 rpm for 30 min at room temperature. The molar ratio of zirconium (calculated as Zr), 2-aminoterephthalic acid, and sodium acetate in this system was 1:1:5, the total reaction volume was 15 mL, and the Zr concentration was 0.067 mol / L. The mixture was transferred to a 25 mL polytetrafluoroethylene-lined reactor and crystallized at 90 °C for 24 h. After cooling to room temperature, a light yellow slurry was obtained. The slurry was filtered, and the resulting solid was washed three times with deionized water (20 mL each time) and twice with ethanol (20 mL each time). It was dried at 80 °C for 12 h and then activated under vacuum at 120 °C for 6 h to obtain a powdered UiO-66-NH2 sample.

[0116] Example 13

[0117] 322.2 mg (1 mmol, calculated as Zr) of zirconium oxychloride octahydrate was weighed and dissolved in 10 mL of deionized water by stirring to obtain an aqueous zirconium source system. Separately, 254.2 mg (1 mmol) of 1,2,4,5-benzenetetracarboxylic acid was weighed and added to 10 mL of deionized water, and stirred at 95 °C for 20 min. Then, 642.3 mg (3 mmol) of sodium dihydrogen citrate was added, and stirring was continued for another 20 min to obtain a ligand-modifier aqueous system.

[0118] The zirconium source aqueous system and the ligand-modifier aqueous system were mixed and stirred at 300 rpm for 30 min. The molar ratio of zirconium (calculated as Zr), 1,2,4,5-benzenetetracarboxylic acid, and sodium dihydrogen citrate in this system was 1:1:3, the total volume of the reaction system was 20 mL, and the Zr concentration was 0.05 mol / L. The mixture was transferred to a 50 mL polytetrafluoroethylene-lined reactor and crystallized at 100 °C for 48 h. After cooling to room temperature, a white slurry was obtained. The slurry was filtered, and the resulting solid was washed three times with deionized water (30 mL each time) and twice with ethanol (30 mL each time). It was dried at 60 °C for 12 h and then activated under vacuum at 100 °C for 8 h to obtain a powdered UiO-66-(COOH)2 sample.

[0119] Example 14

[0120] 966.6 mg (3 mmol, calculated as Zr) of zirconium oxychloride octahydrate was weighed and dissolved in 15 mL of deionized water by stirring to obtain an aqueous zirconium source system. Separately, 210.1 mg (1 mmol) of trimesic acid was weighed and added to 5 mL of deionized water. Under stirring, 3.0 mL (3 mmol) of 1.0 mol / L sodium hydroxide aqueous solution was added dropwise over 20 min. After stirring at 60 °C for 30 min, 820.3 mg (10 mmol) of sodium acetate was added, and stirring continued for another 20 min to obtain a ligand-modifier aqueous system.

[0121] The ligand-modifier aqueous system was added to the zirconium source aqueous system within 30 min, stirred at 300 rpm for 30 min, and deionized water was added to bring the total volume of the reaction system to 30 mL. The molar ratio of zirconium (calculated as Zr), trimesic acid, and sodium acetate in this system was 1:0.33:3.33, and the Zr concentration was 0.10 mol / L. The mixture was transferred to a 50 mL polytetrafluoroethylene-lined reactor and crystallized at 100 °C for 18 h. After cooling to room temperature, a white slurry was obtained. The slurry was filtered, and the resulting solid was washed three times with deionized water (30 mL each time) and twice with ethanol (30 mL each time). It was dried at 80 °C for 12 h and then activated under vacuum at 150 °C for 8 h to obtain a powdered MOF-808 sample.

[0122] Example 15

[0123] Weigh 322.2 mg (1 mmol, calculated as Zr) of zirconium oxychloride octahydrate and add it to 5 mL of deionized water. Stir at room temperature until dissolved to obtain the zirconium source aqueous phase system. Separately weigh 242.3 mg (1 mmol) of 4,4′-biphenyl dicarboxylic acid and add it to 6 mL of deionized water. Under stirring, add 1.8 mL (1.8 mmol) of 1.0 mol / L sodium hydroxide aqueous solution dropwise over 20 min, followed by stirring at 60 °C for 40 min to obtain the 4,4′-biphenyl dicarboxylate aqueous phase system. Weigh 486.1 mg (3 mmol) of disodium succinate and add it to 5 mL of deionized water. After stirring to dissolve, add it to the above ligand aqueous phase system and continue stirring for 20 min to obtain the ligand-modifier aqueous phase system.

[0124] The ligand-modifier aqueous system was added to the zirconium source aqueous system within 30 min, and stirred at 300 rpm for 30 min at room temperature. Deionized water was then added to bring the total volume of the reaction system to 20 mL. The molar ratio of zirconium (calculated as Zr), 4,4′-biphenyldicarboxylic acid, and disodium succinate in this system was 1:1.0:3.0, and the Zr concentration was 0.05 mol / L. The mixture was transferred to a 50 mL polytetrafluoroethylene-lined reactor and crystallized at 120 °C for 24 h. After cooling to room temperature, a white slurry was obtained. The slurry was filtered, and the resulting solid was washed three times with deionized water (30 mL each time) and twice with ethanol (30 mL each time). It was dried at 80 °C for 12 h and then activated under vacuum at 150 °C for 8 h to obtain a powdered UiO-67 sample.

[0125] Comparative Example 1

[0126] Weigh 322.2 mg (1 mmol) of zirconium oxychloride octahydrate and add it to 6 mL of deionized water. Stir until dissolved to obtain an aqueous solution of the zirconium source. Separately weigh 116.1 mg (1 mmol) of fumaric acid and 249.20 mg (1.5 mmol) of terephthalic acid and add them to 9 mL of deionized water. Stir and sonicate for 20 min to form a ligand-modifier mixture.

[0127] The zirconium source aqueous solution was mixed with the ligand-modifier mixture, stirred at room temperature for 30 min, and then transferred to a 25 mL polytetrafluoroethylene-lined reactor. The molar ratio of zirconium (calculated as Zr), fumaric acid, and terephthalic acid in this system was 1:1:1.5, and the total volume of the reaction system was 15 mL. Based on the total volume of 15.0 mL after mixing, the Zr concentration was 0.067 mol / L, the fumaric acid concentration was 0.067 mol / L, and the terephthalic acid concentration was 0.1 mol / L. The reactor was placed in a 120℃ oven for crystallization reaction for 20 h. After cooling to room temperature, the mixture was filtered. The obtained solid was washed three times with deionized water and twice with ethanol, dried at 80℃ for 12 h, and then activated under vacuum at 120℃ for 6 h to obtain the comparative example sample.

[0128] Comparative Example 2

[0129] 322.2 mg (1 mmol, calculated as Zr) of zirconium oxychloride octahydrate was weighed and added to 5 mL of deionized water. The solution was stirred at room temperature until dissolved to obtain an aqueous zirconium source solution. Separately, 166.1 mg (1 mmol) of terephthalic acid was weighed and added to 5 mL of deionized water. Under stirring, 1.5 mL (1.5 mmol) of a 1.0 mol / L sodium hydroxide aqueous solution was added dropwise over 20 min. The mixture was then stirred at 60 °C for 30 min to obtain an aqueous terephthalate system. 272.3 mg (2 mmol) of p-methylbenzoic acid was weighed and added to 10 mL of deionized water. The mixture was stirred at 60 °C for 20 min, then added to the aqueous terephthalate system and stirred for another 20 min to obtain a ligand-modifier mixed system.

[0130] The ligand-modifier mixture was added to a zirconium source aqueous solution over 30 min, stirred at 300 rpm for 30 min at room temperature, and deionized water was added to bring the total volume of the reaction system to 25 mL. The molar ratio of zirconium (calculated as Zr), terephthalic acid, and p-methylbenzoic acid in this system was 1:1:2. The mixture was transferred to a 50 mL polytetrafluoroethylene-lined reactor and crystallized at 100 °C for 18 h. After cooling to room temperature, the mixture was filtered. The resulting solid was washed three times with deionized water and twice with ethanol, dried at 80 °C for 12 h, and then activated under vacuum at 120 °C for 6 h to obtain the comparative example 2 sample.

[0131] Comparative Example 3

[0132] 322.2 mg (1 mmol, calculated as Zr) of zirconium oxychloride octahydrate was weighed and added to 5 mL of deionized water, stirred until dissolved, to obtain an aqueous zirconium source solution. Separately, 181.1 mg (1 mmol) of 2-aminoterephthalic acid was weighed and added to 7 mL of deionized water, stirred at 60 °C for 30 min, and sonicated for 10 min to obtain an aqueous ligand system. 313.1 mg (2 mmol) of p-chlorobenzoic acid was weighed and added to 10 mL of deionized water, stirred at 60 °C for 20 min, and then added to the aqueous ligand system and stirred for another 20 min to obtain a ligand-modifier mixed system.

[0133] An aqueous solution of the zirconium source was added to the ligand-modifier mixture, and the mixture was stirred at 300 rpm for 30 min at room temperature. Deionized water was then added to bring the total volume of the reaction system to 25 mL. The molar ratio of zirconium (calculated as Zr), 2-aminoterephthalic acid, and p-chlorobenzoic acid in this system was 1:1:2. The mixture was transferred to a 50 mL polytetrafluoroethylene-lined reactor and crystallized at 90 °C for 24 h. After cooling to room temperature, the mixture was filtered. The resulting solid was washed three times with deionized water and twice with ethanol, dried at 80 °C for 12 h, and then activated under vacuum at 120 °C for 6 h to obtain the comparative example 3 sample.

[0134] Comparative Example 4

[0135] Weigh 322.2 mg (1 mmol, calculated as Zr) of zirconium oxychloride octahydrate and add it to 10 mL of deionized water. Stir until dissolved to obtain an aqueous zirconium source solution. Separately weigh 254.2 mg (1 mmol) of 1,2,4,5-benzenetetracarboxylic acid and add it to 10 mL of deionized water. Stir at 95 °C for 20 min to obtain an aqueous ligand system. Weigh 313.1 mg (2 mmol) of m-chlorobenzoic acid and add it to 10 mL of deionized water. Stir at 60 °C for 20 min, then add the aqueous ligand system and continue stirring for 20 min to obtain a ligand-modifier mixed system.

[0136] The zirconium source aqueous solution was mixed with the ligand-modifier mixture and stirred at 300 rpm for 30 min. The molar ratio of zirconium (calculated as Zr), 1,2,4,5-benzenetetracarboxylic acid, and m-chlorobenzoic acid in this system was 1:1:2, the total volume of the reaction system was 30 mL, and the Zr concentration was 0.033 mol / L. The mixture was transferred to a 50 mL polytetrafluoroethylene-lined reactor and crystallized at 100 °C for 48 h. After cooling to room temperature, the mixture was filtered. The obtained solid was washed three times with deionized water and twice with ethanol, dried at 60 °C for 12 h, and then activated under vacuum at 100 °C for 8 h to obtain Comparative Example 4 sample.

[0137] Comparative Example 5

[0138] 966.6 mg (3 mmol, calculated as Zr) of zirconium oxychloride octahydrate was weighed and added to 15 mL of deionized water, stirred until dissolved, to obtain an aqueous zirconium source solution. Separately, 210.1 mg (1 mmol) of trimesic acid was weighed and added to 5 mL of deionized water. Under stirring, 3.0 mL (3 mmol) of 1.0 mol / L sodium hydroxide aqueous solution was added dropwise over 20 min, followed by stirring at 60 °C for 30 min, to obtain a trimesic acid aqueous phase system. 272.3 mg (2 mmol) of m-methylbenzoic acid was weighed and added to 10 mL of deionized water, stirred at 60 °C for 20 min, then added to the aforementioned trimesic acid aqueous phase system and stirring continued for 20 min, to obtain a ligand-modifier mixed system.

[0139] The ligand-modifier mixture was added to a zirconium source aqueous solution within 30 min, stirred at 300 rpm for 30 min, and deionized water was added to bring the total volume of the reaction system to 40 mL. The molar ratio of zirconium (calculated as Zr), trimesic acid, and m-methylbenzoic acid in this system was 1:0.33:0.67. The mixture was transferred to a 50 mL polytetrafluoroethylene-lined reactor and crystallized at 100 °C for 18 h. After cooling to room temperature, the mixture was filtered. The obtained solid was washed three times with deionized water and twice with ethanol, dried at 80 °C for 12 h, and activated under vacuum at 150 °C for 8 h to obtain the comparative example 5 sample.

[0140] Comparative Example 6

[0141] 322.2 mg (1 mmol, calculated as Zr) of zirconium oxychloride octahydrate was weighed and added to 5 mL of deionized water. The solution was stirred at room temperature until dissolved to obtain an aqueous zirconium source solution. Separately, 242.3 mg (1 mmol) of 4,4′-biphenyl dicarboxylic acid was weighed and added to 6 mL of deionized water. Under stirring, 1.8 mL (1.8 mmol) of 1.0 mol / L sodium hydroxide aqueous solution was added dropwise over 20 min. The mixture was then stirred at 60 °C for 40 min to obtain an aqueous 4,4′-biphenyl dicarboxylate system. 272.3 mg (2 mmol) of p-methylbenzoic acid was weighed and added to 10 mL of deionized water. The mixture was stirred at 60 °C for 20 min, then added to the aqueous 4,4′-biphenyl dicarboxylate system and stirred for another 20 min to obtain a ligand-modifier mixed system.

[0142] The ligand-modifier mixture was added to a zirconium source aqueous solution over 30 min, and stirred at 300 rpm for 30 min at room temperature. Deionized water was then added to bring the total volume of the reaction system to 25 mL. The molar ratio of zirconium (calculated as Zr), 4,4′-biphenyldicarboxylic acid, and p-methylbenzoic acid in this system was 1:1:2. The mixture was transferred to a 50 mL polytetrafluoroethylene-lined reactor and crystallized at 120 °C for 24 h. After cooling to room temperature, the mixture was filtered. The resulting solid was washed three times with deionized water and twice with ethanol, dried at 80 °C for 12 h, and then activated under vacuum at 150 °C for 8 h to obtain Comparative Example 6 sample.

[0143] like Figure 1 The images show the powder X-ray diffraction (PXRD) patterns of MOF-801 materials prepared in Examples 1, 3-8, and simulated XRD patterns of MOF-801 materials. Figure 1 It can be seen that the positions of the main diffraction peaks of the samples in each embodiment correspond to the simulated MOF-801 pattern, indicating that the non-volatile organic carboxylate conditioning system of the present invention can form the MOF-801 crystal phase in the aqueous phase.

[0144] like Figure 2 The figures show the nitrogen adsorption isotherms at 77 K for the MOF-801 materials prepared in Examples 1, 3-8. The P / P0 ratio on the horizontal axis represents the relative pressure, which is dimensionless, where P is the equilibrium partial pressure of nitrogen in the test system and P0 is the saturated vapor pressure of nitrogen at 77 K. All samples from these examples exhibit the adsorption characteristics of microporous materials, indicating that the prepared MOF-801 materials possess a detectable pore structure.

[0145] Figure 3 The simulated XRD patterns of the samples obtained in Examples 11-15 using PXRD and the corresponding target zirconium-based MOFs are given. Figure 4 The nitrogen adsorption isotherms of the samples obtained in Examples 11-15 at 77 K are given, further confirming the feasibility of the non-volatile organic carboxylate regulator provided by the present invention in the preparation of other zirconium-based metal-organic framework materials.

[0146] Figure 5 The PXRD patterns of the samples obtained in Comparative Examples 1-6 and the simulated XRD patterns of the corresponding target zirconium-based MOFs are presented. Figure 6 Nitrogen adsorption isotherms at 77 K are presented for the samples obtained in Comparative Examples 1-6. Compared with the corresponding salt-type regulator examples, the target characteristic diffraction peaks of the comparative examples are significantly weakened or disappeared, and the overall nitrogen adsorption performance is reduced, indicating that under the aqueous phase preparation conditions, the use of the corresponding free organic carboxylic acid is not conducive to the formation of the target crystal phase and pore structure.

[0147] This invention uses water as the primary reaction medium and non-volatile organic carboxylate salts as the source of carboxylate ions and competitive coordination modifiers. It combines direct aqueous phase feeding or quantitative deprotonated feeding methods for different ligands to form an aqueous phase preparation method suitable for MOF-801, UiO-66, UiO-66-NH2, UiO-66-(COOH)2, UiO-67, and MOF-808. The salt-type modifier provides a low-volatility, easily quantifiable alternative to traditional free small-molecule carboxylic acid regulation systems such as formic acid and acetic acid, and is compatible with scale-up batch reactor processes. The zirconium-based metal-organic framework materials prepared by this invention can be used in adsorption separation and other fields.

[0148] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing zirconium-based metal-organic framework materials by regulating the use of non-volatile organic carboxylate, characterized in that, Includes the following steps: The zirconium source was dissolved in water and stirred until homogeneous to obtain an aqueous zirconium source system. Based on zirconium-based metal-organic framework materials, organic polycarboxylic acid ligands were determined, and the organic polycarboxylic acid ligands were added to water. Then, non-volatile organic carboxylic acid salt regulators were added and mixed evenly to obtain a ligand-regulator aqueous phase system. The zirconium source aqueous system and the ligand-modifier aqueous system were mixed evenly and crystallization reaction was carried out in the aqueous phase. Then, the mixture was cooled to room temperature to obtain a zirconium-based metal-organic framework material slurry. The zirconium-based metal-organic framework material slurry was subjected to solid-liquid separation, followed by washing, drying and vacuum activation to obtain the zirconium-based metal-organic framework material. The zirconium-based metal-organic framework material includes one of MOF-801, UiO-66, UiO-66-NH2, UiO-67, UiO-68, MOF-808, MOF-545, PCN-224, NU-1000, NU-901, DUT-67, DUT-68, DUT-69, MIP-202(Zr), or MIP-206; When the zirconium-based metal-organic framework material is any one of UiO-66, UiO-67, and MOF-808, sodium hydroxide aqueous solution is added for deprotonation treatment before adding the non-volatile organic carboxylate regulator. When the zirconium-based metal-organic framework material is UiO-66, the organic polycarboxylic acid ligand is terephthalic acid, and the molar ratio of sodium hydroxide to terephthalic acid is (0.5~2.0):1; When the zirconium-based metal-organic framework material is UiO-67, the organic polycarboxylic acid ligand is 4,4′-biphenyldicarboxylic acid, and the molar ratio of sodium hydroxide to 4,4′-biphenyldicarboxylic acid is (1.0~2.0):1; When the zirconium-based metal-organic framework material is MOF-808, the organic polycarboxylic acid ligand is pyromellitic acid, and the molar ratio of sodium hydroxide to pyromellitic acid is (1.0~3.0):

1.

2. The method for preparing zirconium-based metal-organic framework materials according to claim 1, characterized in that, The zirconium source includes one or more of zirconium dichloride octahydrate, zirconium oxynitrate, zirconium nitrate, zirconium sulfate, zirconium acetate, or their hydrates; And / or, the organic polycarboxylic acid ligand includes one of fumaric acid, 2-aminoterephthalic acid, 1,2,4,5-benzenetetracarboxylic acid, terephthalic acid, 4,4′-biphenyldicarboxylic acid, and pyromellitic acid.

3. The method for preparing zirconium-based metal-organic framework materials by adjusting the use of non-volatile organic carboxylate as described in claim 1, characterized in that, The organic carboxylic acid in the non-volatile organic carboxylic acid salt regulator includes one or more of the following: aromatic carboxylic acids, substituted aromatic carboxylic acids, aliphatic monocarboxylic acids, aliphatic polycarboxylic acids, hydroxycarboxylic acids, aminocarboxylic acids, and heterocyclic carboxylic acids. And / or, the cations in the non-volatile organic carboxylate regulator include one or more of alkali metal ions, alkaline earth metal ions, and ammonium ions; And / or, the solubility of the free organic carboxylic acid corresponding to the non-volatile organic carboxylic acid salt regulator in water at 25°C is not higher than 5 g / L.

4. The method for preparing zirconium-based metal-organic framework materials by adjusting the use of non-volatile organic carboxylate as described in claim 1, characterized in that, The non-volatile organic carboxylate regulators include one or more of the following: sodium benzoate, disodium terephthalate, sodium pyridine-2-carboxylate, sodium acetate, sodium dihydrogen citrate, disodium succinate, sodium o-chlorobenzoate, sodium m-chlorobenzoate, sodium p-chlorobenzoate, sodium o-bromobenzoate, sodium m-bromobenzoate, sodium p-bromobenzoate, sodium o-methylbenzoate, sodium m-methylbenzoate, sodium p-methylbenzoate, sodium dichlorobenzoate, sodium dibromobenzoate, sodium dimethylbenzoate, sodium fluorobenzoate, sodium iodobenzoate, sodium hydroxybenzoate, sodium methoxybenzoate, sodium citrate, trisodium citrate dihydrate, sodium malate, sodium tartrate, sodium oxalate, sodium malonate, sodium succinate, sodium glutarate, sodium adipate, sodium decanoate, sodium gluconate, sodium glycolate, sodium lactate, sodium salicylate, sodium nicotinic acid, and sodium pyridinecarboxylate.

5. The method for preparing zirconium-based metal-organic framework materials according to claim 1, characterized in that, When the zirconium-based metal-organic framework material is MOF-801, UiO-66-NH2, UiO-66 or UiO-67, the molar ratio of zirconium, the organic polycarboxylic acid ligand and the non-volatile organic carboxylic acid salt regulator in the zirconium source is 1: (0.5~2.0): (0.1~20). And / or, when the zirconium-based metal-organic framework material is MOF-808, the molar ratio of zirconium, the organic polycarboxylic acid ligand and the non-volatile organic carboxylic acid salt modifier in the zirconium source is 1:(0.2~0.6):(0.1~20). And / or, the concentration of zirconium in the zirconium source is 0.01~1 mol / L.

6. The method for preparing zirconium-based metal-organic framework materials according to claim 1, characterized in that, When the zirconium-based metal-organic framework material is either MOF-801 or UiO-66-NH2, the preparation of the ligand-modifier aqueous system includes: At a temperature of 20~100℃, organic polycarboxylic acid ligands are added to water, followed by the addition of non-volatile organic carboxylic acid salt regulators. The mixture is stirred for 10~120 min until homogeneous, thus obtaining a ligand-regulator aqueous phase system.

7. The method for preparing zirconium-based metal-organic framework materials according to claim 1, characterized in that, When the zirconium-based metal-organic framework material is any one of UiO-66, UiO-67, and MOF-808, the preparation of the ligand-modifier aqueous system includes: At a temperature of 20~100℃, organic polycarboxylic acid ligands are added to water, followed by deprotonation treatment with 0.1~4 mol / L sodium hydroxide aqueous solution. Then, non-volatile organic carboxylic acid salt regulators are added, and the mixture is stirred for 10~120 min until homogeneous to obtain a ligand-regulator aqueous phase system.

8. The method for preparing zirconium-based metal-organic framework materials according to claim 1, characterized in that, The zirconium source aqueous system and the ligand-modifier aqueous system are mixed and stirred at 50-500 rpm for 10-120 min. After the mixture is homogeneous, a crystallization reaction is carried out at 60-140℃ for 2-48 h. After the reaction is completed, the mixture is cooled to room temperature to obtain a zirconium-based metal-organic framework material slurry.

9. The method for preparing zirconium-based metal-organic framework materials by adjusting the non-volatile organic carboxylate according to claim 8, characterized in that, The crystallization reaction is carried out in a sealed reaction vessel; or, the crystallization reaction is carried out in a batch reactor with a total volume of 1~10 L and equipped with mechanical stirring, jacket temperature control and reflux condensation device, with a reflux temperature of 95~105℃ and a reflux reaction time of 6~30 h. And / or, the zirconium-based metal-organic framework material slurry is subjected to solid-liquid separation by vacuum filtration, pressure filtration, or centrifugation at 3000~10000 rpm for 5~30 min, followed by washing with water and ethanol 1~5 times, drying at 60~120℃ for 6~24 h, and vacuum activation at 80~200℃ for 4~24 h to obtain the zirconium-based metal-organic framework material.

10. A zirconium-based metal-organic framework material prepared by the method of preparing zirconium-based metal-organic framework materials using the non-volatile organic carboxylate as described in any one of claims 1 to 9.

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