A porous adsorption material for purifying organic waste gas and a preparation method thereof

Abstract

The present invention relates to the technical field of porous adsorption materials, and discloses a porous adsorption material for purifying organic waste gas and a preparation method thereof; the method comprises the following steps: ultrasonically dispersing modified titanium carbide MXene C in ethylene glycol, adding a palladium acetate solution, stirring evenly, heating to 150-155 °C for reaction for 2-2.5 h, cooling to room temperature, filtering, washing with deionized water and ethanol, and drying in vacuum at 70 °C for 12 h to obtain the porous adsorption material.

Description

Technical Field

[0001] The invention relates to the technical field of porous adsorption materials, in particular to a porous adsorption material for purifying organic waste gas and a preparation method thereof. Background Art

[0002] Volatile Organic Compounds (VOCs), as the main precursors of ozone and fine particulate matter PM2.5, are one of the important causes of complex air pollution in my country. Excessive release of VOCs not only seriously threatens the ecological environment, but also poses a huge threat to human health. Therefore, how to efficiently control VOCs has become an environmental problem that needs to be solved urgently.

[0003] At present, there are various technical means to control VOCs. Among them, catalytic oxidation technology is considered to be one of the most effective methods for VOCs removal due to its mature process, simple operation, high efficiency, low energy, and no secondary pollution. The key to catalytic oxidation technology is to find an efficient and stable catalyst. Supported precious metal catalysts are usually used for the efficient degradation of VOCs because of their high catalytic activity under low temperature conditions. However, since the VOCs emitted under actual working conditions contain a variety of complex components, these components often have a poisonous effect on the active components of the catalyst, resulting in a decrease in the activity of the catalyst or even inactivation.

[0004] In recent years, Metal-Organic Frameworks (MOFs) materials have received extensive attention in response to the problem of catalyst deactivation in complex environments. MOFs have high specific surface area, adjustable pore structure and excellent chemical stability. In particular, zirconium (Zr)-based UiO-66 has become an ideal carrier for supported precious metal catalysts due to its high hydrothermal stability and excellent loading capacity for precious metals. By loading precious metal nanoparticles on Zr-based UiO-66, not only can the dispersion and stability of precious metals be effectively improved, but also the structural characteristics of UiO-66 can enhance the catalyst's adsorption capacity for VOCs, thereby improving the catalytic efficiency.

[0005] In addition to catalytic oxidation technology, photocatalytic technology has also been widely studied in the removal of VOCs due to its advantages such as simple equipment, easy operation and sustainability. Photocatalytic technology based on traditional semiconductor materials can effectively degrade VOCs under ultraviolet or visible light irradiation without generating secondary pollution. However, traditional semiconductor photocatalysts have some inherent defects, such as high recombination rate of photogenerated carriers, narrow light response range, weak adsorption capacity for VOCs, and easy accumulation of degradation intermediates to deactivate them. These defects limit the performance and efficiency of traditional photocatalytic materials in practical applications.

[0006] Based on the above background, the development of a porous material with both high catalytic and adsorption performance, which can operate stably in complex environments for a long time, has become a current research hotspot. MOFs materials represented by Zr-based UiO-66 have shown great application potential in the fields of supported noble metal catalysts and photocatalysts due to their unique physical and chemical properties. By optimizing the structural design of MOFs, further improving their specific surface area, pore size distribution and chemical stability, and combining noble metal nanoparticles or modified semiconductor materials, it is expected to significantly improve the removal efficiency of VOCs and provide a new and efficient solution for the purification of organic waste gases.

[0007] Therefore, the present invention aims to provide a porous adsorption material based on MOFs materials, especially Zr-based UiO-66, and its preparation method to achieve efficient adsorption and catalytic degradation of VOCs with complex components, overcome the deficiencies in the prior art, and promote the development of VOCs treatment technology towards a more efficient and stable direction. This new material is not only applicable to the treatment of VOCs in the wood industry, but also can be widely used in the purification of organic waste gases in other industries, making an important contribution to air pollution control and environmental protection. Summary of the Invention

[0008] The purpose of the present invention is to provide a porous adsorption material for purifying organic waste gases and its preparation method to solve the problems raised in the above background technology.

[0009] To solve the above technical problems, the present invention provides the following technical solutions:

[0010] A preparation method of a porous adsorption material for purifying organic waste gases, comprising the following steps:

[0011] S1: Add lithium fluoride to a hydrochloric acid solution, stir evenly, add carbon aluminum titanium MXene, heat to 35 - 38 °C and stir for 24 h, add the mixed solution to deionized water, centrifuge and wash until the pH is neutral, filter, ultrasonically disperse the precipitate in deionized water, centrifuge, and take the supernatant to obtain thin sheet titanium carbide MXene;

[0012] Further, the mass ratio of lithium fluoride to carbon aluminum titanium MXene is 1:1;

[0013] Further, the concentration of the hydrochloric acid solution is 27 - 28 wt%,

[0014] S2: Add sodium tungstate dihydrate to deionized water, adjust the pH to 1.2 - 1.3 with 0.3 M hydrochloric acid, sequentially add oxalic acid solution and ammonium sulfate, stir evenly, add titanium carbide MXene flakes, disperse by ultrasonic treatment, heat to 180 - 185 °C and react for 16 - 18 h, filter, wash with deionized water and ethanol, dry in vacuum at 80 °C, heat to 450 °C and calcine for 1 - 2 h to obtain modified titanium carbide MXene A;

[0015] Further, the mass ratio of sodium tungstate dihydrate: oxalic acid: ammonium sulfate: titanium carbide MXene flakes is (9.277 - 9.7408):(7.0900 - 7.4445):(28.1250 - 29.5312):5.01;

[0016] Further, the concentration of the oxalic acid solution is 105.037 mM;

[0017] S3: Add zirconium chloride and terephthalic acid to N,N - dimethylformamide, dissolve by ultrasonic treatment, add modified titanium carbide MXene A, heat to 120 °C and crystallize for 24 h, cool to room temperature, filter, wash with N,N - dimethylformamide and ethanol, dry in vacuum at 70 - 80 °C to obtain modified titanium carbide MXene B;

[0018] Further, the mass ratio of zirconium chloride: terephthalic acid: modified titanium carbide MXene A is (0.28 - 0.53):(0.19 - 0.34):5.01;

[0019] S4: Add modified titanium carbide MXene B to an aqueous solution of zinc nitrate, heat to 60 - 65 °C and react for 1 - 1.5 h, add sodium carbonate solution to adjust the pH to 7 - 7.5, keep the temperature for reaction for 5 - 5.5 h, let it stand and cool for 1 h, filter, wash the filtrate with deionized water until the pH is neutral, dry in vacuum at 110 °C, heat to 250 - 300 °C and calcine for 3.5 - 4 h to obtain modified titanium carbide MXene C;

[0020] Further, the mass ratio of modified titanium carbide MXene B: aqueous solution of zinc nitrate is (0.618 - 0.976):(0.86 - 1.3588);

[0021] Further, the concentration of the aqueous solution of zinc nitrate is 0.5 M, and the concentration of the sodium carbonate solution is 0.5 M;

[0022] S5: Disperse modified titanium carbide MXene C by ultrasonic treatment in ethylene glycol, add palladium acetate solution, stir evenly, heat to 150 - 155 °C and react for 2 - 2.5 h, cool to room temperature, filter, wash with deionized water and ethanol, dry in vacuum at 70 °C for 12 h to obtain a porous adsorption material.

[0023] Further, the concentration ratio of the modified titanium carbide MXene C: palladium acetate solution is 1:(1 - 2);

[0024] Further, the concentration of the palladium acetate solution is 0.03 M.

[0025] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0026] The present invention uses titanium carbide MXene with a large specific surface area and high surface activity as a carrier. First, a large number of needle-like tungsten trioxide (modified titanium carbide MXene A) are loaded on its surface. Using tungsten trioxide as a secondary carrier, a UiO-66 metal-organic framework (modified titanium carbide MXene B) is synthesized on its surface, maximizing the loading amount of UiO-66 per unit area. At the same time, due to the needle-like structure of tungsten trioxide, the contact area between UiO-66 and VOCs pollutants can be greatly increased, which can not only expand the light response range of the photocatalyst but also enhance the adsorption capacity for VOCs by using the porous structure and high specific surface area of MOFs, thereby reducing the recombination rate of photo-generated carriers and improving the photocatalytic efficiency. In addition, the adjustable pore size and excellent chemical stability of MOFs materials enable them to exhibit stronger anti-toxicity ability during the photocatalytic degradation process, effectively extending the service life of the photocatalyst.

[0027] By controlling the calcination temperature during the preparation of tungsten trioxide-loaded titanium carbide MXene, a large number of titanium dioxide nanoparticles grow uniformly on the edges of titanium carbide MXene, alleviating the stacking of titanium carbide MXene sheets, which is beneficial to the improvement of the overall specific surface area of the composite material and the increase of adsorption sites, further improving the photocatalytic performance of the porous adsorption material.

[0028] The present invention further uses UiO-66 as a carrier. Different from the traditional single-loaded catalyst Pd, in the form of internal encapsulation and external loading, zinc oxide is encapsulated inside UiO-66 (modified titanium carbide MXene C), and catalyst Pd nanoparticles are loaded on the surface of UiO-66 (porous adsorption material). The purpose is to maximize the use of space to load multiple catalysts per unit volume. By controlling the reaction variables, the encapsulation of zinc oxide and the surface loading of Pd nanoparticles are prevented from blocking the pores, and the purpose of purifying VOCs organic waste gas is achieved through the adsorption-catalytic oxidation technology. Specific Embodiments

[0029] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0030] In the following examples, the carbon-aluminum-titanium MXene has a specification of 400 mesh and is purchased from Eleven Technology Co., Ltd.; the rest of the raw materials are commercially available.

[0031] Example 1: A preparation method of a porous adsorbent material for purifying organic waste gas: S1: Add 30 mL of 37% v / v hydrochloric acid to 10 mL of deionized water, add 2 g of lithium fluoride, stir evenly, add 2 g of carbon-aluminum-titanium MXene, heat to 35 °C and stir for 24 h. Add the mixed solution to deionized water, centrifuge and wash at 3500 r until the pH is neutral, add deionized water for filtration to collect the precipitate. Ultrasonically disperse the precipitate in deionized water at 900 W, centrifuge at 3500 r, and take the supernatant to obtain thin flake titanium carbide MXene;

[0032] S2: Dilute 7.4445 g of oxalic acid to 750 mL to obtain an oxalic acid solution. Add 9.7408 g of sodium tungstate dihydrate to 300 mL of deionized water, adjust the pH to 1.2 with 0.3 M hydrochloric acid, sequentially add the oxalic acid solution and 29.5312 g of ammonium sulfate, stir evenly, add 5.01 g of thin flake titanium carbide MXene, ultrasonically disperse, heat to 180 °C and react for 16 h, filter, wash with deionized water and ethanol, and dry in vacuum at 80 °C. Heat to 450 °C and calcine for 1 h to obtain modified titanium carbide MXene A;

[0033] S3: Add 0.28 g of zirconium chloride and 0.19 g of terephthalic acid to 50 mL of N,N-dimethylformamide, ultrasonically dissolve, add 5.01 g of modified titanium carbide MXene A, heat to 120 °C and crystallize for 24 h. Cool to room temperature, filter, wash with N,N-dimethylformamide and ethanol, and dry in vacuum at 70 °C to obtain modified titanium carbide MXene B;

[0034] S4: Add 0.618 g of modified titanium carbide MXene B to 0.86 g of zinc nitrate aqueous solution, heat to 60 °C and react for 1 h, add sodium carbonate solution to adjust the pH to 7, keep warm and react for 5 h, stand and cool for 1 h, filter, wash the filtrate with deionized water until the pH is neutral, dry in vacuum at 110 °C, and calcine at 250 °C for 4 h to obtain modified titanium carbide MXene C;

[0035] S5: Ultrasonically disperse 1 g of modified titanium carbide MXene C in ethylene glycol, add 1 g of palladium acetate solution, stir evenly, heat to 150 °C and react for 2 h. Cool to room temperature, filter, wash with deionized water and ethanol, and dry in vacuum at 70 °C for 12 h to obtain the porous adsorbent material.

[0036] Example 2: A preparation method of a porous adsorbent material for purifying organic waste gas: S1: Add 30 mL of 37% v / v hydrochloric acid to 10 mL of deionized water, add 2 g of lithium fluoride, stir evenly, add 2 g of carbon aluminum titanium MXene, heat to 35 °C and stir for 24 h. Add the mixed solution to deionized water, centrifuge and wash at 3500 r until the pH is neutral, add deionized water for filtration to collect the precipitate. Ultrasonically disperse the precipitate in deionized water at 900 W, centrifuge at 3500 r, and take the supernatant to obtain titanium carbide MXene flakes;

[0037] S2: Dilute 7.4445 g of oxalic acid to 750 mL to obtain an oxalic acid solution. Add 9.7408 g of sodium tungstate dihydrate to 300 mL of deionized water, adjust the pH to 1.2 with 0.3 M hydrochloric acid, sequentially add the oxalic acid solution and 29.5312 g of ammonium sulfate, stir evenly, add 5.01 g of titanium carbide MXene flakes, ultrasonically disperse, heat to 180 °C and react for 16 h, filter, wash with deionized water and ethanol, dry in vacuum at 80 °C, heat to 450 °C and calcine for 1 h to obtain modified titanium carbide MXene A;

[0038] S3: Add 0.53 g of zirconium chloride and 0.34 g of terephthalic acid to 50 mL of N,N-dimethylformamide, ultrasonically dissolve, add 5.01 g of modified titanium carbide MXene A, heat to 120 °C and crystallize for 24 h, cool to room temperature, filter, wash with N,N-dimethylformamide and ethanol, dry in vacuum at 70 °C to obtain modified titanium carbide MXene B;

[0039] S4: Add 0.618 g of modified titanium carbide MXene B to 0.86 g of zinc nitrate aqueous solution, heat to 60 °C and react for 1 h, add sodium carbonate solution to adjust the pH to 7, keep warm and react for 5 h, stand and cool for 1 h, filter, wash the filtrate with deionized water until the pH is neutral, dry in vacuum at 110 °C, and calcine at 250 °C for 4 h to obtain modified titanium carbide MXene C;

[0040] S5: Ultrasonically disperse 1 g of modified titanium carbide MXene C in ethylene glycol, add 1 g of palladium acetate solution, stir evenly, heat to 150 °C and react for 2 h, cool to room temperature, filter, wash with deionized water and ethanol, dry in vacuum at 70 °C for 12 h to obtain a porous adsorbent material.

[0041] Example 3: A preparation method of a porous adsorption material for purifying organic waste gas: S1: Add 30 mL of 37% v / v hydrochloric acid to 10 mL of deionized water, add 2 g of lithium fluoride, stir evenly, add 2 g of carbon aluminum titanium MXene, heat to 35 °C and stir for 24 h. Add the mixed solution to deionized water, centrifuge and wash at 3500 r until the pH is neutral, add deionized water for filtration to collect the precipitate. Ultrasonically disperse the precipitate in deionized water at 900 W, centrifuge at 3500 r, and take the supernatant to obtain thin sheet titanium carbide MXene;

[0042] S2: Dilute 7.4445 g of oxalic acid to 750 mL to obtain an oxalic acid solution. Add 9.7408 g of sodium tungstate dihydrate to 300 mL of deionized water, add 0.3 M hydrochloric acid to adjust the pH to 1.2, successively add the oxalic acid solution and 29.5312 g of ammonium sulfate, stir evenly, add 5.01 g of thin sheet titanium carbide MXene, ultrasonically disperse, heat to 180 °C and react for 16 h, filter, wash with deionized water and ethanol, dry in vacuum at 80 °C, heat to 450 °C and calcine for 1 h to obtain modified titanium carbide MXene A;

[0043] S3: Add 0.28 g of zirconium chloride and 0.19 g of terephthalic acid to 50 mL of N,N-dimethylformamide, ultrasonically dissolve, add 5.01 g of modified titanium carbide MXene A, heat to 120 °C and crystallize for 24 h, cool to room temperature, filter, wash with N,N-dimethylformamide and ethanol, dry in vacuum at 70 °C to obtain modified titanium carbide MXene B;

[0044] S4: Add 0.618 g of modified titanium carbide MXene B to 0.86 g of an aqueous solution of zinc nitrate, heat to 60 °C and react for 1 h, add sodium carbonate solution to adjust the pH to 7, keep warm and react for 5 h, stand and cool for 1 h, filter, wash the filtrate with deionized water until the pH is neutral, dry in vacuum at 110 °C, and calcine at 250 °C for 4 h to obtain modified titanium carbide MXene C;

[0045] S5: Ultrasonically disperse 1 g of modified titanium carbide MXene C in ethylene glycol, add 2 g of palladium acetate solution, stir evenly, heat to 150 °C and react for 2 h, cool to room temperature, filter, wash with deionized water and ethanol, dry in vacuum at 70 °C for 12 h to obtain the porous adsorption material.

[0046] Comparative Example 1: A preparation method of a porous adsorbent material for purifying organic waste gas: S2: Dilute 7.4445 g of oxalic acid to 750 mL to obtain an oxalic acid solution. Add 9.7408 g of sodium tungstate dihydrate to 300 mL of deionized water, adjust the pH to 1.2 with 0.3 M hydrochloric acid, successively add the oxalic acid solution and 29.5312 g of ammonium sulfate, stir evenly, add 5.01 g of thin sheet titanium carbide MXene, ultrasonically disperse, heat to 180 °C and react for 16 h, filter, wash with deionized water and ethanol, dry in vacuum at 80 °C, heat to 350 °C and calcine for 1 h to obtain modified titanium carbide MXene A;

[0047] The remaining steps are the same as those in Example 1.

[0048] Comparative Example 2: A preparation method of a porous adsorbent material for purifying organic waste gas: S2: Dilute 7.4445 g of oxalic acid to 750 mL to obtain an oxalic acid solution. Add 9.7408 g of sodium tungstate dihydrate to 300 mL of deionized water, adjust the pH to 1.2 with 0.3 M hydrochloric acid, successively add the oxalic acid solution and 29.5312 g of ammonium sulfate, stir evenly, add 5.01 g of thin sheet titanium carbide MXene, ultrasonically disperse, heat to 180 °C and react for 16 h, filter, wash with deionized water and ethanol, dry in vacuum at 80 °C, heat to 550 °C and calcine for 1 h to obtain modified titanium carbide MXene A;

[0049] The remaining steps are the same as those in Example 1.

[0050] Comparative Example 3: A preparation method of a porous adsorbent material for purifying organic waste gas: S3: Add 0.57 g of zirconium chloride and 0.36 g of terephthalic acid to 50 mL of N,N-dimethylformamide, ultrasonically dissolve, add 5.01 g of modified titanium carbide MXene A, heat to 120 °C and crystallize for 24 h, cool to room temperature, filter, wash with N,N-dimethylformamide and ethanol, dry in vacuum at 70 °C to obtain modified titanium carbide MXene B;

[0051] The remaining steps are the same as those in Example 1.

[0052] Comparative Example 4: A preparation method of a porous adsorbent material for purifying organic waste gas: S4: Add 0.618 g of modified titanium carbide MXene B to 1.4 g of an aqueous solution of zinc nitrate, heat to 60 °C and react for 1 h, add a sodium carbonate solution to adjust the pH to 7, keep the temperature and react for 5 h, let it stand and cool for 1 h, filter, wash the filtrate with deionized water until the pH is neutral, dry in vacuum at 110 °C, and calcine at 250 °C for 4 h to obtain modified titanium carbide MXene C;

[0053] The remaining steps are the same as those in Example 1.

[0054] Comparative Example 5: A preparation method of a porous adsorbent material for purifying organic waste gas: S3: Add 0.23 g of zirconium chloride and 0.19 g of amino-terephthalic acid to 50 mL of N,N-dimethylformamide, dissolve by ultrasonic treatment, add 5.01 g of modified titanium carbide MXene A, heat to 120 °C for crystallization for 24 h, cool to room temperature, filter, wash with N,N-dimethylformamide and ethanol, and dry in vacuum at 70 °C to obtain modified titanium carbide MXene B;

[0055] The remaining steps are the same as those in Example 1.

[0056] Comparative Example 6: A preparation method of a porous adsorbent material for purifying organic waste gas: S5: Add 1 g of modified titanium carbide MXene C to 1 g of palladium acetate solution, stir evenly, dry overnight at room temperature, dry in vacuum at 70 °C for 12 h, and reduce at 200 °C for 2 h under a hydrogen atmosphere to obtain a porous adsorbent material.

[0057] The remaining steps are the same as those in Example 1.

[0058] Experiment: After pressing the porous adsorbent material with a powder press, select those with a particle size of 20-60 mesh.

[0059] VOCs catalytic degradation performance test:

[0060] Place the porous adsorbent material in a U-shaped quartz reaction tube. Toluene liquid is vaporized in a vaporization chamber by a 30% O2 / Ar mixed gas with a flow rate of 35 mL / min and high-purity Ar with a flow rate of 15 mL / min introduced by an injector and an injection pump at a certain injection rate. By adjusting the injection rate, control the toluene concentration to be 1000 ppm. The total flow rate of the reaction gas is 50 mL / min, and the space velocity is 30000 mL / (g·h); the initial concentration of toluene, the concentration of toluene and CO2 after the reaction are detected by an on-line gas chromatograph equipped with two hydrogen flame ionization detectors.

[0061] VOCs t = 1 - C t / C0 × 100%;

[0062] Among them, VOCs t is the VOCs conversion rate; C t is the concentration of VOCs after the reaction (ppm); C0 is the initial concentration of VOCs (ppm).

[0063] Record the temperature when the VOCs conversion rate is 90% to evaluate the catalytic degradation performance.

[0064] Water resistance performance test of the porous adsorbent material:

[0065] Before 30% O2 / Ar at 35 mL / min and Ar at 15 mL / min enter the vaporization chamber, they are introduced into a bubbler filled with deionized water. Water vapor is introduced into the reaction system by means of gas carrying. The bubbler is placed in a water bath, and by adjusting the temperature of the water bath, the saturated vapor pressure of water vapor is changed, thereby controlling the content of water vapor introduced into the reaction system. Other conditions remain unchanged.

[0066] W = φP v / P;

[0067] where W is the water vapor content (vol.%), φ is the relative humidity (%), and P v is the saturated vapor pressure of water vapor at a specific temperature (Pa), and P is the standard atmospheric pressure (Pa).

[0068] Measure the VOCs conversion rate at 20.0 vol.% water vapor in the reaction system, and record the temperature when the VOCs conversion rate is 90% to evaluate the catalytic degradation performance.

[0069] Photocatalytic performance test:

[0070] A light source is set 15 cm above the quartz reaction tube. The porous adsorption material is placed in the quartz reaction tube. The 37% v / v formaldehyde solution is heated to 90 °C, and formaldehyde gas is evaporated into the reaction tube. The humidity in the reaction tube is adjusted by the bubbling method to simulate real environmental conditions. It is placed in the dark for 60 min to reach the adsorption-desorption equilibrium, and then the light is turned on. After a fixed illumination time, sampling is carried out by combining an air pump and a gas flowmeter. Finally, based on the color reaction between formaldehyde and acetylacetone, according to the methods in the international standard ISO4614 and the national standard GB / T15516 - 1195 "Determination of Formaldehyde in Air Quality - Acetylacetone Spectrophotometry", the formaldehyde concentration is calculated, and the formaldehyde degradation rate is calculated.

[0071] PA t = 1 - P t / P0×100%;

[0072] where PA t is the formaldehyde conversion rate, P t / is the concentration of formaldehyde after the reaction (ppm), and P0 is the initial concentration of formaldehyde (ppm).

[0073] The experimental data are shown in Table 1 below.

[0074]

[0075] Table 1 Performance test data table of porous adsorption material

[0076] Conclusion: The porous adsorption material prepared in the present invention has excellent organic waste gas purification function.

[0077] In Comparative Example 1, the calcination temperature was too low, and fewer irregular titanium dioxide nanoparticles grew on the edges of titanium carbide MXene, resulting in a decrease in catalytic performance. At the same time, it was not conducive to the dispersion of titanium carbide MXene sheets (the sheets were prone to stacking), as well as the increase in specific surface area and adsorption sites, leading to a decrease in performance.

[0078] In Comparative Example 2, the calcination temperature was too high, resulting in the dense titanium dioxide particles grown on titanium carbide MXene completely wrapping titanium carbide MXene, and the sheet structure was damaged, leading to a decrease in performance.

[0079] In Comparative Example 3, the amount of UiO-66 loaded on the rod-shaped tungsten trioxide on the surface of titanium carbide MXene was too much, resulting in a large amount of deposition blocking the photocatalytic effect and being not conducive to the photocatalytic reaction, leading to a decrease in performance.

[0080] In Comparative Example 4, too much metal was filled inside UiO-66, resulting in a significant decrease in pore volume, pore blockage, distortion or loss of the connecting ligands, leading to the destruction of the order of the MOF structure and a decrease in performance.

[0081] In Comparative Example 5, Pd was loaded on the surface of UiO-66 0 The number of species decreased, leading to a decrease in performance.

[0082] In Comparative Example 6, UiO-66 was functionalized with NH2 groups. The introduction of NH2 into UiO-66 led to a decrease in space volume and an increase in the weight of MOFs. After loading Pd, the specific surface area and total pore volume of MOFs decreased, leading to a decrease in performance.

[0083] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A preparation method of a porous adsorption material for purifying organic waste gas, characterized in that: It includes the following steps: ultrasonically disperse modified titanium carbide MXene C in ethylene glycol, add palladium acetate solution, stir evenly, heat for reaction, cool to room temperature, filter, wash with deionized water and ethanol, and vacuum dry at 70 °C for 12 h to obtain a porous adsorption material; The preparation method of the modified titanium carbide MXene C includes the following steps: add modified titanium carbide MXene B into an aqueous solution of zinc nitrate, heat to 60 - 65 °C for reaction for 1 - 1.5 h, add sodium carbonate solution to adjust the pH to 7 - 7.5, keep the temperature for reaction for 5 - 5.5 h, let it stand and cool for 1 h, filter, wash the filtrate with deionized water until the pH is neutral, vacuum dry at 110 °C, and calcine to obtain modified titanium carbide MXene C; The preparation method of the modified titanium carbide MXene B includes the following steps: add zirconium chloride and terephthalic acid into N,N - dimethylformamide, ultrasonically dissolve, add modified titanium carbide MXene A, heat to 120 °C for crystallization for 24 h, cool to room temperature, filter, wash with N,N - dimethylformamide and ethanol, and vacuum dry at 70 - 80 °C to obtain modified titanium carbide MXene B; The preparation method of the modified titanium carbide MXene A includes the following steps: add sodium tungstate dihydrate into deionized water, add 0.3 M hydrochloric acid to adjust the pH to 1.2 - 1.3, successively add oxalic acid solution and ammonium sulfate, stir evenly, add flake titanium carbide MXene, ultrasonically disperse, heat to 180 - 185 °C for reaction for 16 - 18 h, filter, wash with deionized water and ethanol, vacuum dry at 80 °C, and calcine to obtain modified titanium carbide MXene A; The preparation method of the flake titanium carbide MXene includes the following steps: add lithium fluoride into hydrochloric acid solution, stir evenly, add carbon aluminum titanium MXene, heat to 35 - 38 °C and stir for 24 h, add the mixed solution into deionized water, centrifuge and wash until the pH is neutral, filter, ultrasonically disperse the precipitate in deionized water, centrifuge, and take the supernatant to obtain flake titanium carbide MXene; the mass ratio of lithium fluoride to carbon aluminum titanium MXene is 1:

1.

2. The preparation method of a porous adsorbent material for purifying organic waste gas according to claim 1, characterized in that: The mass ratio of the modified titanium carbide MXene C to the palladium acetate solution is 1:(1 - 2); the heating reaction temperature is 150 - 155 °C, and the heating reaction time is 2 - 2.5 h.

3. The preparation method of a porous adsorption material for purifying organic waste gas according to claim 1, characterized in that: The mass ratio of the modified titanium carbide MXene B to the aqueous solution of zinc nitrate is (0.618 - 0.976):(0.86 - 1.3588); during the preparation process of the modified titanium carbide MXene C, the calcination temperature is 250 - 300 °C, and the calcination time is 3.5 - 4 h.

4. The preparation method of a porous adsorption material for purifying organic waste gas according to claim 1, characterized in that: The mass ratio of zirconium chloride:terephthalic acid:modified titanium carbide MXene A is (0.28 - 0.53):(0.19 - 0.34):5.

01.

5. The preparation method of a porous adsorbent material for purifying organic waste gas according to claim 1, characterized in that: The mass ratio of sodium tungstate dihydrate: oxalic acid: ammonium sulfate: titanium carbide MXene flakes is (9.277 - 9.7408):(7.0900 - 7.4445):(28.1250 - 29.5312):5.01; during the preparation of the modified titanium carbide MXene A, the calcination temperature is 450 °C and the calcination time is 1 - 2 h.

6. A porous adsorbent material prepared by the method for preparing a porous adsorbent material for purifying organic waste gas according to any one of claims 1 - 5.

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