A MOFs-based sponge composite material, a preparation method and application thereof

Abstract

This invention relates to the field of hydrogen sulfide adsorption and purification technology, and discloses a MOFs-based sponge composite material, its preparation method, and its application. The composite material contains a modified sponge matrix and MOFs material supported on the modified sponge matrix, wherein the MOFs material contains metal salts and organic ligands in a mass ratio of 1-5:1; the composite material has a BET specific surface area of ​​90-300 m². 2 / g, average pore size 1-10nm, pore volume 0.05-0.5cm³ 3 / g; the dynamic adsorption capacity calculated from the adsorption breakthrough curve of hydrogen sulfide gas by this composite material is 1-14 mmol / g, the breakthrough time is 0.3-10h, and the saturation time is 1-15h. The MOFs-based sponge composite material provided by this invention has the characteristics of large adsorption capacity and high dynamic adsorption efficiency.

Description

Technical Field

[0001] This invention relates to the field of hydrogen sulfide adsorption and purification technology, specifically to a MOFs-based sponge composite material, its preparation method, and its application. Background Technology

[0002] MOFs (Metal-Organic Facility-Containing) materials are a novel type of porous material formed by the self-assembly of metal ions and organic ligands containing nitrogen and oxygen. MOFs possess high porosity and high specific surface area (1000–7000 m²). 2 Its excellent characteristics, such as rich and tunable structure, abundant metal ions and ligands, and unsaturated metal sites, make it promising for applications in gas adsorption and separation, catalysis, and sensing.

[0003] Hydrogen sulfide is highly harmful to the human body. Low concentrations can cause fever, dizziness, and difficulty breathing, while high concentrations can lead to suffocation. In industry, the acidity and corrosiveness of hydrogen sulfide can severely corrode equipment and pipelines, causing most catalysts to fail. The byproducts of the combustion of hydrogen sulfide in natural gas and petroleum gas, released into the atmosphere, contribute to acid rain.

[0004] Currently, H2S capture and removal technologies can be broadly classified into two categories: dry and wet methods. Wet methods include amine solution absorption, ionic liquid methods, and biological desulfurization; dry methods include adsorption and membrane separation. Wet methods are mainly used for desulfurization applications with high sulfur content and large scale, while deep desulfurization for concentrations as low as one part per million requires dry methods. Among these, the use of metal-organic frameworks (MOFs) to adsorb and remove hydrogen sulfide shows promising application prospects.

[0005] However, MOFs materials are powdery, and before application, the powder must be processed or integrated to achieve high mechanical strength and low pressure drop. This process reduces the specific surface area and adsorption performance of the material. Furthermore, the granulation process of MOFs is complex, which greatly increases the cost of material preparation and limits the progress of engineering applications of MOFs materials in adsorption treatment.

[0006] CN109926031A discloses a method for preparing MOFs / sponge composite materials. The method involves loading MOFs material BUT 10 onto a sponge using a solvothermal method. The composite material prepared by this method can retain the porous properties of the MOFs material itself and can also control the size of the composite material, which helps to realize the recycling and regeneration of MOFs / sponge composite materials and can effectively reduce application costs.

[0007] CN110038540A discloses a method for preparing a sponge-composite metal-organic framework material for adsorption and separation, which involves loading MOF materials into the internal pores of a sponge support through a two-step in-situ growth method. The composite material obtained by this method has the characteristics of large CO2 adsorption capacity, high adsorption and separation selectivity, and stable adsorption and separation performance.

[0008] However, none of the MOFs / sponge composites prepared by the aforementioned methods involve the adsorption and removal of hydrogen sulfide gas, and the existing MOFs / sponge composites have low adsorption efficiency for gases. Summary of the Invention

[0009] The purpose of this invention is to solve the problem of low dynamic adsorption efficiency of hydrogen sulfide adsorption materials in the prior art.

[0010] To achieve the above objectives, a first aspect of the present invention provides a MOFs-based sponge composite material, which contains a modified sponge matrix and MOFs material loaded on the modified sponge matrix, wherein the MOFs material contains a metal salt and an organic ligand in a mass ratio of 1-10:1; the composite material has a BET specific surface area of ​​90-300 m². 2 / g, the average pore size of the composite material is 1-10nm, and the pore volume of the composite material is 0.05-0.5cm. 3 / g;

[0011] The dynamic adsorption capacity obtained by calculating the adsorption breakthrough curve of hydrogen sulfide gas by the composite material is 1-14 mmol / g, the breakthrough time is 0.3-10h, and the saturation time is 1-15h.

[0012] A second aspect of the present invention provides a method for preparing the MOFs-based sponge composite material described in the first aspect, the method comprising:

[0013] (1) In the presence of a modifier and solvent I, the sponge matrix is ​​modified to obtain a modified sponge matrix; and

[0014] In the presence of solvent II, the metal salt and the organic ligand are brought into contact and mixed to obtain a mixed solution;

[0015] (2) The modified sponge matrix is ​​immersed in the mixed solution to carry out a contact reaction to obtain a precursor;

[0016] (3) The precursor is subjected to a third drying treatment.

[0017] The third aspect of the present invention provides the application of the MOFs-based sponge composite material described in the first aspect in the removal of hydrogen sulfide.

[0018] The MOFs-based sponge composite material provided by this invention has the characteristics of large adsorption capacity and high dynamic adsorption efficiency. When used for the removal of hydrogen sulfide gas, it can effectively solve the problems of low dynamic adsorption capacity of traditional hydrogen sulfide adsorption materials and the inability to directly use powdered MOFs materials. Detailed Implementation

[0019] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0020] In this invention, unless otherwise stated, the room temperature or normal temperature refers to 25±2℃.

[0021] As previously stated, a first aspect of the present invention provides a MOFs-based sponge composite material comprising a modified sponge matrix and MOFs material loaded on the modified sponge matrix, wherein the MOFs material contains a metal salt and an organic ligand in a mass ratio of 1-10:1; the composite material has a BET specific surface area of ​​90-300 m². 2 / g, the average pore size of the composite material is 1-10nm, and the pore volume of the composite material is 0.05-0.5cm. 3 / g;

[0022] The dynamic adsorption capacity obtained by calculating the adsorption breakthrough curve of hydrogen sulfide gas by the composite material is 1-14 mmol / g, the breakthrough time is 0.3-10h, and the saturation time is 1-15h.

[0023] Preferably, the BET specific surface area of ​​the composite material is 120-300 m². 2 / g, the average pore size of the composite material is 1-4nm, and the pore volume of the composite material is 0.2-0.4cm. 3 / g. The inventors discovered that, by adopting the specific embodiment under this preferred condition, composite materials with higher dynamic adsorption capacity and adsorption efficiency can be prepared.

[0024] Preferably, the mass ratio of the metal salt to the organic ligand is 1.2-5:1. The inventors have discovered that, using this preferred embodiment, MOF-based sponge composite materials with higher dynamic adsorption capacity can be prepared.

[0025] Preferably, the metal salt of the MOF material is selected from at least one of zinc nitrate hexahydrate, copper nitrate trihydrate, scandium trifluoromethanesulfonate, ferric chloride hexahydrate, and zirconium tetrachloride.

[0026] More preferably, the metal salt of the MOF material is selected from at least one of zinc nitrate hexahydrate, copper nitrate trihydrate, and zirconium tetrachloride.

[0027] Preferably, the organic ligand of the MOF material is selected from at least one of 2-aminoterephthalic acid, 2,6-naphthalenedicarboxylic acid, trimesic acid, biphenyl-3,3',5,5'-tetracarboxylic acid, and terephthalic acid. More preferably, the organic ligand of the MOF material is selected from at least one of biphenyl-3,3',5,5'-tetracarboxylic acid, trimesic acid, and terephthalic acid.

[0028] According to a particularly preferred embodiment, the metal salt of the MOF material is zirconium tetrachloride, and the organic ligand is terephthalic acid. The inventors have discovered that, in this preferred embodiment, the prepared composite material exhibits superior dynamic adsorption capacity.

[0029] Preferably, the sponge matrix is ​​polyurethane sponge and / or melamine sponge.

[0030] As previously stated, a second aspect of the present invention provides a method for preparing the MOFs-based sponge composite material described in the first aspect, the method comprising:

[0031] (1) In the presence of a modifier and solvent I, the sponge matrix is ​​modified to obtain a modified sponge matrix; and

[0032] In the presence of solvent II, the metal salt and the organic ligand are brought into contact and mixed to obtain a mixed solution;

[0033] (2) The modified sponge matrix is ​​immersed in the mixed solution to carry out a contact reaction to obtain a precursor;

[0034] (3) The precursor is subjected to a third drying treatment.

[0035] Preferably, in step (1), the modifier is selected from at least one of polydimethylsiloxane, sodium dodecylbenzenesulfonate, sodium carboxymethyl cellulose, and dopamine hydrochloride.

[0036] Preferably, in step (1), the conditions for the modification treatment include at least: a temperature of 20-40°C and a time of 2-48h.

[0037] More preferably, in step (1), the conditions for the modification treatment include at least: a temperature of 20-40°C and a time of 12-24h.

[0038] Preferably, in step (1), the amount of solvent I is controlled so that the concentration of the modifier in solvent I is 0.01-0.05 g / mL.

[0039] Preferably, in step (1), the method further includes: pre-treating the modified matrix before modifying the sponge matrix.

[0040] Preferably, in step (1), the pretreatment includes sequentially cutting, first cleaning, and first drying of the sponge substrate.

[0041] To facilitate subsequent processing of the sponge substrate, the sponge substrate is cut into cylinders with an average diameter of 3-8 mm and an average length of 10-30 mm.

[0042] Preferably, in step (1), the solvent for the first cleaning is ethanol, and the conditions for the first cleaning include at least: ultrasonic power of 30-50kw, temperature of 20-40℃, and time of 20-40min.

[0043] Preferably, in step (1), the conditions for the first drying process include at least: a temperature of 100-120°C and a time of 2-4 hours.

[0044] Preferably, in step (1), the method further includes: subjecting the material undergoing the modification treatment to a second cleaning and a second drying treatment in sequence.

[0045] Preferably, in step (1), the solvent for the second cleaning is ethanol.

[0046] Preferably, in step (1), the conditions for the second drying process include at least: a temperature of 100-120°C and a time of 2-4 hours.

[0047] Preferably, in step (1), the mass ratio of the metal salt to the organic ligand is 1-10:1, more preferably 1.2-5:1.

[0048] Preferably, in step (1), the amount of solvent II is controlled so that the concentration of the metal salt in the mixed solution is 0.01-0.04 mol / mL.

[0049] Preferably, in step (1), the contact mixing conditions include at least: a temperature of 20-40°C and a time of 1.5-2.5h.

[0050] Preferably, in step (1), solvent I and solvent II are each independently selected from at least one of N,N-dimethylformamide and ethanol.

[0051] Preferably, in step (2), the conditions for the contact reaction include at least: a temperature of 70-150°C and a time of 18-72h.

[0052] More preferably, in step (2), the conditions for the contact reaction include at least: a temperature of 90-120°C and a time of 48-65 h. The inventors have found that, in this preferred embodiment, the prepared composite material exhibits superior dynamic adsorption capacity.

[0053] Preferably, in step (2), the method further includes: subjecting the mixed solution system to ultrasonic treatment before carrying out the contact reaction.

[0054] Preferably, in step (2), the conditions for ultrasonic treatment include at least: ultrasonic power of 30-50 kW, temperature of 20-40 °C, and time of 20-40 min.

[0055] Preferably, in step (3), the conditions for the third drying process include at least: a temperature of 80-130°C and a time of 1-5 hours.

[0056] More preferably, in step (3), the conditions for the third drying process include at least: a temperature of 110-120°C and a time of 2-4 hours.

[0057] As previously stated, a third aspect of the present invention provides the application of the MOFs-based sponge composite material described in the first aspect in the removal of hydrogen sulfide.

[0058] The present invention will be described in detail below through examples. In the following examples, unless otherwise specified, all raw materials and instruments used are commercially available products.

[0059] Sponge matrix: melamine sponge, purchased from Jiangsu Jieya Home Furnishings Co., Ltd.;

[0060] Modifier 1: Sodium carboxymethyl cellulose, CAS No. 9004-32-4, grade C804625, purchased from Shanghai Maclean Biochemical Technology Co., Ltd.

[0061] Modifier 2: Sodium dodecylbenzenesulfonate, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0062] Modifier 3: Dopamine hydrochloride, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0063] Modifier 4: KH550, purchased from Wuhan Hualun Organosilicon Co., Ltd.;

[0064] Metal salt 1: Zirconium tetrachloride, purchased from Shanghai Maclean Biochemical Technology Co., Ltd.;

[0065] Metal salt 2: Scandium trifluoromethanesulfonate, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0066] Metal salt 3: Copper nitrate trihydrate, purchased from Shanghai Maclean Biochemical Technology Co., Ltd.

[0067] Metal salt 4: Ferric nitrate hexahydrate, purchased from Shanghai Maclean Biochemical Technology Co., Ltd.

[0068] Organic ligand 1: terephthalic acid, purchased from Shanghai Maclean Biochemical Technology Co., Ltd.;

[0069] Organic ligand 2: biphenyl-3,3',5,5'-tetracarboxylic acid, purchased from Shanghai Maclean Biochemical Technology Co., Ltd.;

[0070] Organic ligand 3: pyromellitic acid, purchased from Shanghai Maclean Biochemical Technology Co., Ltd.;

[0071] In the following examples, N,N-dimethylformamide and ethanol are analytical grade reagents.

[0072] Example 1

[0073] This embodiment provides a method for preparing MOFs-based sponge composite materials, the method comprising the following steps:

[0074] (1) Cut the sponge substrate into cylinders with an average diameter of 6 mm and an average length of 10 mm, then clean it with anhydrous ethanol. After cleaning, remove the sponge substrate and squeeze out the excess anhydrous ethanol. Finally, place it in an oven for the first drying process to obtain the cleaned sponge substrate.

[0075] The conditions for the first cleaning were: ultrasonic power of 40 kW, temperature of room temperature, and time of 30 min.

[0076] The conditions for the first drying process are: temperature 120℃, time 3h;

[0077] (2) Add 1g of modifier 1 to 20mL of ethanol to obtain a modifier 1 solution with a concentration of 0.05g / mL. Immerse the cleaned sponge matrix in the modifier 1 solution for modification treatment. Then, wash the modified material three times with anhydrous ethanol and place it in an oven for a second drying treatment to obtain the modified sponge matrix; and

[0078] 2g of metal salt 1, 1.5g of organic ligand 1 and 50mL of N,N-dimethylformamide were contacted and mixed to obtain a mixed solution; the mass ratio of metal salt 1 to organic ligand 1 was 4:3, and the concentration of metal salt 1 in the mixed solution was 0.03mol / mL.

[0079] The modification treatment conditions were: room temperature and 24 hours.

[0080] The conditions for the second drying process are: temperature 110℃, time 3h;

[0081] The conditions for contact mixing were: temperature 25℃, time 2 hours;

[0082] (3) The modified sponge matrix obtained above was immersed in 50 mL of mixed solution and ultrasonically treated to obtain MOFs-sponge system. The MOFs-sponge system was placed in a reaction vessel for contact reaction to obtain precursor.

[0083] The conditions for ultrasonic treatment were: ultrasonic power of 40 kW, temperature of room temperature, and time of 30 min.

[0084] The conditions for the contact reaction were: temperature 120℃ and time 48h;

[0085] (4) After the aforementioned precursor was naturally cooled to room temperature, it was washed twice with anhydrous ethanol and placed in an oven for a third drying treatment to obtain MOFs-based sponge composite material S1.

[0086] The conditions for the third drying process are: temperature 120℃ and time 3h.

[0087] In MOFs-based sponge composite S1, the specific surface area is 193 m². 2 / g, average pore size is 3.3nm, pore volume is 0.393cm³. 3 / g.

[0088] Example 2

[0089] This embodiment provides a method for preparing MOFs-based sponge composite materials, the method comprising the following steps:

[0090] (1) Cut the sponge substrate into cylinders with an average diameter of 6 mm and an average length of 10 mm, then clean it with anhydrous ethanol. After cleaning, remove the sponge substrate and squeeze out the excess anhydrous ethanol. Finally, place it in an oven for the first drying process to obtain the cleaned sponge substrate.

[0091] The conditions for the first cleaning were: ultrasonic power of 40 kW, temperature of room temperature, and time of 30 min.

[0092] The conditions for the first drying process are: temperature 100℃, time 3h;

[0093] (2) Add 1g of modifier 2 to 20mL of ethanol to obtain a modifier 2 solution with a concentration of 0.05g / mL. Immerse the cleaned sponge matrix in the modifier 2 solution for modification treatment. Then, wash the modified material three times with anhydrous ethanol and place it in an oven for a second drying treatment to obtain the modified sponge matrix; and

[0094] 2.4 g of metal salt 2, 1.2 g of organic ligand 2 and 50 mL of ethanol were contacted and mixed to obtain a mixed solution; the mass ratio of metal salt 2 to organic ligand 2 was 2:1, and the concentration of metal salt 2 in the mixed solution was 0.04 mol / mL.

[0095] The modification treatment conditions were: room temperature and 18 hours.

[0096] The conditions for the second drying process are: temperature 100℃, time 3h;

[0097] The conditions for contact mixing were: temperature 25℃, time 2.5h;

[0098] (3) The modified sponge matrix obtained above was immersed in 50 mL of mixed solution and ultrasonically treated to obtain MOFs-sponge system. The MOFs-sponge system was placed in a reaction vessel for contact reaction to obtain precursor.

[0099] The conditions for ultrasonic treatment were: ultrasonic power of 40 kW, temperature of room temperature, and time of 30 min.

[0100] The conditions for the contact reaction were: temperature 100℃ and time 65h.

[0101] (4) After the aforementioned precursor was naturally cooled to room temperature, it was washed three times with anhydrous ethanol and placed in an oven for a third drying treatment to obtain MOFs-based sponge composite material S2.

[0102] The conditions for the third drying process are: temperature 115℃ and time 3h.

[0103] In MOFs-based sponge composite S2, the specific surface area is 168 m². 2 / g, average pore size 3.4nm, pore volume 0.346cm³ 3 / g.

[0104] Example 3

[0105] This embodiment provides a method for preparing MOFs-based sponge composite materials, the method comprising the following steps:

[0106] (1) Cut the sponge substrate into cylinders with an average diameter of 6 mm and an average length of 10 mm, then clean it with anhydrous ethanol. After cleaning, remove the sponge substrate and squeeze out the excess anhydrous ethanol. Finally, place it in an oven for the first drying process to obtain the cleaned sponge substrate.

[0107] The conditions for the first cleaning were: ultrasonic power of 40 kW, temperature of room temperature, and time of 30 min.

[0108] The conditions for the first drying process are: temperature 110℃, time 3h;

[0109] (2) Add 1g of modifier 3 to 20mL of ethanol to obtain a modifier 3 solution with a concentration of 0.05g / mL. Immerse the cleaned sponge matrix in the modifier 3 solution for modification treatment. Then, wash the modified material three times with anhydrous ethanol and place it in an oven for a second drying treatment to obtain the modified sponge matrix; and

[0110] 2.46 g of metal salt 3, 0.5 g of organic ligand 3 and 50 mL of N,N-dimethylformamide were contacted and mixed to obtain a mixed solution; the mass ratio of metal salt 3 to organic ligand 3 was 5:1, and the concentration of metal salt 3 in the mixed solution was 0.01 mol / mL.

[0111] The modification treatment conditions were: room temperature and 18 hours.

[0112] The conditions for the second drying process are: temperature 100℃, time 3h;

[0113] The conditions for contact mixing were: temperature 25℃, time 1.5h;

[0114] (3) The modified sponge matrix obtained above was immersed in 50 mL of mixed solution and ultrasonically treated to obtain MOFs-sponge system. The MOFs-sponge system was placed in a reaction vessel for contact reaction to obtain precursor.

[0115] The conditions for ultrasonic treatment were: ultrasonic power of 40 kW, temperature of room temperature, and time of 30 min.

[0116] The conditions for the contact reaction were: temperature 90℃ and time 55h.

[0117] (4) After the aforementioned precursor was naturally cooled to room temperature, it was washed twice with anhydrous ethanol and placed in an oven for a third drying treatment to obtain MOFs-based sponge composite material S3.

[0118] The conditions for the third drying process are: temperature 110℃ and time 3h.

[0119] In MOFs-based sponge composite S3, the specific surface area is 268 m². 2 / g, with an average pore size of 1.4nm and a pore volume of 0.218cm³. 3 / g.

[0120] Example 4

[0121] In this embodiment, MOFs-based sponge composite material was prepared according to the method of Example 1. The difference is that in step (2), the amount of metal salt 1 used is 1.5g, that is, the mass ratio of metal salt 1 to organic ligand 1 is 1:1.

[0122] The remaining steps are the same as in Example 1, resulting in MOFs-based sponge composite material S4.

[0123] In MOFs-based sponge composite S4, the specific surface area is 128 m². 2 / g, average pore size is 3.5nm, pore volume is 0.193cm³ 3 / g.

[0124] Example 5

[0125] In this embodiment, MOFs-based sponge composite material was prepared according to the method of Example 1. The difference is that in step (2), metal salt 1 was replaced with metal salt 4 of equal mass.

[0126] The remaining steps are the same as in Example 1, and MOFs-based sponge composite material S5 is obtained.

[0127] In MOFs-based sponge composite S5, the specific surface area is 124 m². 2 / g, average pore size is 1.52nm, pore volume is 0.133cm³. 3 / g.

[0128] Example 6

[0129] In this embodiment, MOFs-based sponge composite material was prepared according to the method of Example 1, except that the contact mixing time in step (2) was 0.5 h.

[0130] The remaining steps are the same as in Example 1, and MOFs-based sponge composite material S6 is obtained.

[0131] In MOF-based sponge composite S6, the specific surface area is 190.6 m². 2 / g, with an average pore size of 3.4nm and a pore volume of 0.293cm³. 3 / g.

[0132] Example 7

[0133] In this embodiment, MOFs-based sponge composite material was prepared according to the method of Example 1, except that the modification treatment time in step (2) was 48 hours.

[0134] The remaining steps are the same as in Example 1, resulting in MOFs-based sponge composite material S7.

[0135] In MOFs-based sponge composite S7, the specific surface area is 163 m².2 / g, with an average pore size of 4.3nm and a pore volume of 0.153cm³. 3 / g.

[0136] Example 8

[0137] In this embodiment, MOFs-based sponge composite material was prepared according to the method of Example 1, except that the contact reaction temperature in step (2) was 70°C.

[0138] The remaining steps are the same as in Example 1, and MOFs-based sponge composite material S8 is obtained.

[0139] In MOFs-based sponge composite S8, the specific surface area is 92 m². 2 / g, average pore size is 3.72nm, pore volume is 0.116cm³. 3 / g.

[0140] Example 9

[0141] In this embodiment, MOFs-based sponge composite material was prepared according to the method of Example 1, except that the contact reaction time in step (2) was 18 hours.

[0142] The remaining steps are the same as in Example 1, and MOFs-based sponge composite material S9 is obtained.

[0143] In MOFs-based sponge composite S9, the specific surface area is 112 m². 2 / g, average pore size is 3.26nm, pore volume is 0.104cm³. 3 / g.

[0144] Example 10

[0145] In this embodiment, MOFs-based sponge composite material was prepared according to the method of Example 1, except that in step (2), modifier 1 was replaced with an equal mass of modifier 4;

[0146] The specific operating steps include:

[0147] (1) Cut the sponge substrate into cylinders with an average diameter of 6 mm and an average length of 10 mm, then clean it with anhydrous ethanol. After cleaning, remove the sponge substrate and squeeze out the excess anhydrous ethanol. Finally, place it in an oven for the first drying process to obtain the cleaned sponge substrate.

[0148] The conditions for the first cleaning were: ultrasonic power of 40 kW, temperature of room temperature, and time of 30 min.

[0149] The conditions for the first drying process are: temperature 120℃, time 3h;

[0150] (2) Add 1g of modifier 4 to 20mL of sodium hydroxide solution (0.5mol / L) to obtain a modifier 4 solution with a concentration of 0.05g / mL. Immerse the cleaned sponge matrix in the modifier 4 solution for modification treatment. Then, wash the modified material three times with anhydrous ethanol and place it in an oven for a second drying treatment to obtain the modified sponge matrix; and

[0151] 2g of metal salt 1, 1.5g of organic ligand 1 and 50mL of N,N-dimethylformamide were contacted and mixed to obtain a mixed solution; the mass ratio of metal salt 1 to organic ligand 1 was 4:3, and the concentration of metal salt 1 in the mixed solution was 0.03mol / mL.

[0152] The modification treatment conditions were: room temperature and 24 hours.

[0153] The conditions for the second drying process are: temperature 110℃, time 3h;

[0154] The conditions for contact mixing were: temperature 25℃, time 2 hours;

[0155] (3) The modified sponge matrix obtained above was immersed in 50 mL of mixed solution and ultrasonically treated to obtain MOFs-sponge system. The MOFs-sponge system was placed in a reaction vessel for contact reaction to obtain precursor.

[0156] The conditions for ultrasonic treatment were: ultrasonic power of 40 kW, temperature of room temperature, and time of 30 min.

[0157] The conditions for the contact reaction were: temperature 120℃ and time 48h;

[0158] (4) After the aforementioned precursor was naturally cooled to room temperature, it was washed twice with anhydrous ethanol and placed in an oven for a third drying treatment to obtain MOFs-based sponge composite material S1.

[0159] The conditions for the third drying process are: temperature 120℃ and time 3h.

[0160] The remaining steps are the same as in Example 1, and MOFs-based sponge composite material S10 is obtained.

[0161] In MOF-based sponge composite S10, the specific surface area is 91.5 m². 2 / g, average pore size is 3.65nm, pore volume is 0.094cm³. 3 / g.

[0162] Comparative Example 1

[0163] MOFs-based sponge composites were prepared according to the method in Example 1, except that the sponge matrix was not modified.

[0164] The specific operating steps include:

[0165] (1) Cut the sponge substrate into cylinders with an average diameter of 6 mm and an average length of 10 mm, then clean it with anhydrous ethanol. After cleaning, remove the sponge substrate and squeeze out the excess anhydrous ethanol. Finally, place it in an oven for the first drying process to obtain the cleaned sponge substrate.

[0166] The conditions for the first cleaning were: ultrasonic power of 40 kW, temperature of room temperature, and time of 30 min.

[0167] The conditions for the first drying process are: temperature 120℃, time 3h;

[0168] (2) 2g of metal salt 1, 1.5g of organic ligand 1 and 50mL of N,N-dimethylformamide were mixed to obtain a mixed solution; the mass ratio of metal salt 1 to organic ligand 1 was 4:3, and the concentration of metal salt 1 in the mixed solution was 0.03mol / mL.

[0169] The conditions for contact mixing were: temperature 25℃, time 2h;

[0170] (3) The aforementioned sponge matrix was immersed in 50 mL of mixed solution and subjected to ultrasonic treatment to obtain MOFs-sponge system. The MOFs-sponge system was placed in a reaction vessel for contact reaction to obtain precursor.

[0171] The conditions for ultrasonic treatment were: ultrasonic power of 40 kW, temperature of room temperature, and time of 30 min.

[0172] The conditions for the contact reaction were: temperature 120℃ and time 48h;

[0173] (4) After the aforementioned precursor was naturally cooled to room temperature, it was washed twice with anhydrous ethanol and placed in an oven for a third drying treatment to obtain MOFs-based sponge composite material S1.

[0174] The conditions for the third drying process are: temperature 120℃ and time 3h.

[0175] In MOF-based sponge composite DS1, the specific surface area is 83 m². 2 / g, average pore size 4.62nm, pore volume 0.037cm³ 3 / g.

[0176] Comparative Example 2

[0177] The MOFs-based sponge composite material was prepared according to the method of Example 1, except that in step (2), the metal salt 1 used was 0.5g, that is, the mass ratio of metal salt 1 to organic ligand 1 was 1:3.

[0178] The remaining steps are the same as in Example 1, and MOFs-based sponge composite material DS2 is obtained.

[0179] In the MOF-based sponge composite DS2, the specific surface area is 63.7 m². 2 / g, average pore size 4.65nm, pore volume 0.062cm³ 3 / g.

[0180] Test case

[0181] The adsorption breakthrough curves of hydrogen sulfide gas on the MOFs-based sponge composites prepared in the examples and comparative examples were determined using a multi-component competitive adsorption breakthrough curve analyzer. The dynamic adsorption capacity of each gram of composite sample for hydrogen sulfide was calculated. The specific results are shown in Table 1.

[0182] The specific test method is as follows: 1g of composite material sample is activated at 150℃ for 3h, and then the activated composite material sample is placed in a penetration column with an inner diameter of 6mm and a sample loading height of 60mm. The adsorption breakthrough curve of MOFs-based sponge composite material for hydrogen sulfide under normal pressure is obtained at a gas flow rate of 100ppm and a purge gas nitrogen of 50ccm, and the dynamic adsorption capacity is calculated.

[0183] The formula for calculating the dynamic adsorption capacity is as follows:

[0184] In the formula, q is the adsorption capacity of the adsorbent, and the unit is mmol / g;

[0185] F represents the adsorption gas velocity, in L / min;

[0186] c0 is the mass concentration of the adsorbate in the feed gas, in mol / L;

[0187] t is the adsorption time, in minutes;

[0188] c(t) is the mass concentration of the adsorbate in the tail gas at time t, in mol / L;

[0189] m represents the adsorbate loading mass, in grams.

[0190] Table 1

[0191]

[0192]

[0193] As can be seen from the results in Table 1, the MOFs-based sponge composite material provided by this invention has the characteristics of large dynamic adsorption capacity and high adsorption efficiency when used for the removal of hydrogen sulfide gas.

[0194] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A MOFs-based sponge composite material, characterized in that, The composite material contains a modified sponge matrix and MOFs material loaded on the modified sponge matrix, and the MOFs material contains a metal salt and an organic ligand in a mass ratio of 1-10:1; the metal salt of the MOFs material is selected from at least one of zinc nitrate hexahydrate, copper nitrate trihydrate, scandium trifluoromethanesulfonate, ferric chloride hexahydrate, and zirconium tetrachloride. The BET specific surface area of ​​the composite material is 90-300 m². 2 / g, the average pore size of the composite material is 1-10nm, and the pore volume of the composite material is 0.05-0.5cm. 3 / g; The dynamic adsorption capacity obtained by analyzing the adsorption breakthrough curve of hydrogen sulfide gas by this composite material is 2.0-14 mmol / g, the breakthrough time is 0.3-10 h, and the saturation time is 1-15 h. The modified sponge matrix is ​​prepared by the following method: the sponge matrix is ​​modified in the presence of a modifier and solvent I to obtain the modified sponge matrix; the solvent I is selected from at least one of N,N-dimethylformamide and ethanol; The modifier is selected from at least one of polydimethylsiloxane, sodium dodecylbenzenesulfonate, sodium carboxymethyl cellulose, and dopamine hydrochloride; The conditions for the modification treatment include at least the following: a temperature of 20-40℃.

2. The composite material according to claim 1, wherein, The BET specific surface area of ​​the composite material is 120-300 m². 2 / g, the average pore size of the composite material is 1-4nm, and the pore volume of the composite material is 0.2-0.4cm. 3 / g.

3. The composite material according to claim 1 or 2, wherein, The mass ratio of the metal salt to the organic ligand is 1.2-5:

1.

4. The composite material according to claim 1 or 2, wherein, The organic ligands of the MOFs material are selected from at least one of 2-aminoterephthalic acid, 2,6-naphthalenedicarboxylic acid, pyromellitic acid, biphenyl-3,3',5,5'-tetracarboxylic acid, and terephthalic acid.

5. The composite material according to any one of claims 1 or 2, wherein, The sponge matrix is ​​polyurethane sponge and / or melamine sponge.

6. A method for preparing the MOFs-based sponge composite material according to any one of claims 1-5, characterized in that, The method includes: (1) In the presence of a modifier and solvent I, the sponge matrix is ​​modified to obtain a modified sponge matrix; and In the presence of solvent II, the metal salt and the organic ligand are brought into contact and mixed to obtain a mixed solution; The modifier is selected from at least one of polydimethylsiloxane, sodium dodecylbenzenesulfonate, sodium carboxymethyl cellulose, and dopamine hydrochloride; the solvent I is selected from at least one of N,N-dimethylformamide and ethanol. The conditions for the modification treatment include at least the following: a temperature of 20-40℃; (2) The modified sponge matrix is ​​immersed in the mixed solution to carry out a contact reaction to obtain a precursor; The conditions for the contact reaction include at least the following: a temperature of 90-120°C and a time of 18-72 hours. (3) The precursor is subjected to a third drying treatment.

7. The method according to claim 6, wherein, In step (1), the conditions for the modification treatment include at least the following: a time of 2-48 hours.

8. The method according to claim 6, wherein, In step (1), the amount of solvent II is controlled so that the concentration of the metal salt in the mixed solution is 0.01-0.04 mol / mL.

9. The method according to claim 6, wherein, In step (3), the conditions for the third drying process include at least the following: a temperature of 80-130°C and a time of 1-5 hours.

10. The application of the MOFs-based sponge composite material according to any one of claims 1-5 in the removal of hydrogen sulfide.

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