Nanosheet-shaped ZSM-5 molecular sieve as well as preparation method and application thereof

Abstract

The invention provides a nano lamellar ZSM-5 molecular sieve and a preparation method and application thereof, the preparation method comprises the following steps: 1) adding a silicon source and an aluminum source into a template agent and water, and uniformly stirring to obtain a crystallization liquid precursor; 2) successively adding a certain amount of mineralizing agent and complexing agent into the crystallization liquid precursor, and uniformly stirring by microwaves to obtain a crystallization liquid; and (3) putting the crystallization liquid into a reactor, and carrying out closed crystallization, so as to obtain the nanosheet-shaped ZSM-5 molecular sieve. Compared with the prior art, the method has the advantages that the high-crystallinity nanosheet-shaped ZSM-5 molecular sieve is prepared through continuous and rapid hydrothermal crystallization under the condition of low-concentration F <->, and huge harm to the environment caused by use of high-concentration F <-> is greatly reduced. In addition, the nano lamellar ZSM-5 molecular sieve which is free of twin crystals and has the thickness of 10-100 nm is prepared. The nanosheet-shaped ZSM-5 molecular sieve shows good adsorption separation and catalytic performance when applied to coal gas carbonyl sulfide removal, isomer separation and methanol-to-olefin.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of molecular sieve material preparation, and in particular to a nanosheet-like ZSM-5 molecular sieve and a preparation method and application thereof. BACKGROUND

[0002] It is known that the adsorption or catalytic performance of ZSM-5 molecular sieve is closely related to its mass transfer path in addition to its specific surface area, pore volume and pore surface properties. When the mass transfer path of ZSM-5 molecular sieve is too long, it will seriously hinder the diffusion of molecules in the pore channel of the molecular sieve, reduce the utilization rate of active sites, and ultimately affect the adsorption or catalytic performance of ZSM-5 molecular sieve. For ZSM-5 molecular sieve, its pore system is composed of straight pores with a b-axis direction pore size of 0.56 nm x 0.53 nm and zigzag pores with an a-axis direction pore size of 0.55 nm x 0.51 nm. Among the two types of pores, the mass transfer path is the shortest and the diffusion barrier is the smallest when the molecules pass through the b-axis direction. Therefore, if nanosheet-like ZSM-5 molecular sieve can be prepared, the diffusion path of the material molecules will be greatly shortened and the utilization rate of the active sites in the pore will be improved, and ultimately ZSM-5 molecular sieve with significantly improved adsorption or catalytic performance will be obtained.

[0003] For the synthesis of nanosheet-like MFI-type molecular sieve, the current methods mainly include gel particle method and nanosheet crystal fusion method, and the gel particle method is the most studied. At present, the gel particle method includes designing and synthesizing new structure template agents to prevent layering, using F - to promote the formation of nanosheet-like MFI-type molecular sieve, adding a regulator to the crystallization liquid, adjusting the pH of the crystallization liquid and etching method. Among the many synthesis methods, the most popular and successful method is the F - assisted crystallization method.

[0004] Dai et al. prepared nanosheet-like silicalite-1 molecular sieve with a thickness of 10-100 nm by F - assisted crystallization method, and the NH4 / SiO2 molar ratio in the crystallization liquid used was 0.8 (Journal of the American Chemical Society, 2021, 143, 1993-2004). Song et al. prepared nanosheet-like ZSM-5 molecular sieve with a thickness of 20-90 nm by F - assisted crystallization method, and the NH4 / SiO2 molar ratio in the crystallization liquid used was 0.8 (Chemistry of Materials, 2022, 34, 3217-3226). Celebi et al. prepared nanosheet-like ZSM-5 molecular sieve with a thickness of 20-90 nm by F -A nanosheet ZSM-5 zeolite with a thickness of 25 nm was prepared by an auxiliary crystallization method, and the molar ratio of NH4 / SiO2 in the crystallization solution used was 1.6 (Microporous and Mesoporous Materials, 2024, 365, 112905). Patent CN108275697 B reports a method for synthesizing nanosheet ZSM-5 zeolite with a thickness of more than 100 nm at low temperature using fluoride. Patent CN117208924 A discloses a preparation method of nanosheet MFI type zeolite, and a nanosheet MFI type zeolite with a thickness of 100-200 nm is prepared by introducing ammonium fluoride as a mineralizer. Although there are many reports on the use of F - as a mineralizer to assist the crystallization of nanosheet ZSM-5 zeolite, the F - concentration in the crystallization solution used is high, and high-concentration F - is harmful to the environment. In addition, the synthesized nanosheet ZSM-5 zeolite contains twin crystals, and the existence of these twin crystals will increase the mass transfer distance, thereby adversely affecting its adsorption or catalytic performance. In particular, when used as a catalyst, high-concentration F - will result in a high F residual amount, which will further adversely affect the catalytic performance of the catalyst. Considering the high efficiency of F - assisted crystallization and the structural integrity of the nanosheet ZSM-5 zeolite prepared, it is extremely important to continue to explore the preparation of nanosheet ZSM-5 zeolite by hydrothermal crystallization at low-concentration F - conditions. In addition, the existing synthesis of nanosheet ZSM-5 zeolite uses traditional hydrothermal crystallization, and the synthesis efficiency needs to be further improved. Compared with traditional hydrothermal crystallization, microwave hydrothermal crystallization is more efficient, but there are few reports on the preparation of nanosheet ZSM-5 zeolite by microwave hydrothermal crystallization. SUMMARY

[0005] The purpose of the present application is to provide a nanosheet ZSM-5 zeolite and a preparation method and application thereof. The present application realizes the hydrothermal crystallization of nanosheet ZSM-5 zeolite with high crystallinity and no twin crystals at low-concentration F conditions by complexing agent assisted F crystallization. Microwave technology is introduced during the stirring pretreatment process of the crystallization solution. The process method is simple to operate, has high synthesis efficiency, good stability and repeatability, and is easy to realize industrialization.

[0006] The purpose of the present application is realized by the following technical solutions:

[0007] The first purpose of the present application is to provide a nanosheet ZSM-5 zeolite, and a preparation method thereof, which comprises the following steps:

[0008] 1) Preparation of crystallization liquid precursor: adding silicon source and aluminum source to template and water, stirring evenly to obtain crystallization liquid precursor;

[0009] 2) preparing a crystallization solution: adding a mineralizer mixture or a mineralizer to the crystallization solution precursor obtained in step 1), stirring the mixture uniformly under microwave conditions, then adding a complexing agent, and continuing to stir the mixture under microwave conditions to obtain a crystallization solution, wherein the mineralizer mixture is a mixture obtained by dissolving the mineralizer in water;

[0010] 3) Hydrothermal crystallization: The crystallization solution obtained in step 2) is placed in a reactor for closed hydrothermal crystallization. After separation, washing, drying and calcination, nano-flake ZSM-5 molecular sieve can be obtained.

[0011] Furthermore, in step 2), the mineralizer is a fluorine-containing compound, and the complexing agent is one or more of disodium ethylenediaminetetraacetic acid or a benzene derivative containing a phenolic hydroxyl group.

[0012] Furthermore, in step 1), the order of adding materials is: first, mix the template and water evenly, then add the aluminum source, and then slowly add the silicon source after the aluminum source is dissolved.

[0013] Furthermore, in step 1), in the crystallization liquid precursor, the molar ratio of the template, silicon in the silicon source, aluminum in the aluminum source, and water is (0.05-0.45):1:(0.01-0.4):(10-30).

[0014] Furthermore, in step 1), the silicon source can be selected from one or more of silicon dioxide (SiO2), silicon powder, solid silica gel, ammonium fluorosilicate, white carbon black, silica sol and tetraethyl orthosilicate.

[0015] Furthermore, the template can be selected from one or more of tetrapropylammonium hydroxide (TPAOH), tetramethylammonium hydroxide, tetraethylammonium hydroxide (TEAH), tetraethylammonium bromide, tetrapropylammonium bromide (TPABr), n-butylamine, n-propylamine, ethylenediamine, etc.

[0016] Furthermore, in step 1), the aluminum source can be selected from one or more of alumina (Al2O3), pseudo-boehmite, aluminum hydroxide, aluminum isopropoxide, aluminum sulfate, aluminum chloride, and the like.

[0017] Further preferably, in step 1), the molar ratio of the crystallization liquid precursor is (0.05-0.45) template: SiO2: (0.005-0.2) Al2O3: (10-30) H2O.

[0018] Further, in step 1), the uniform stirring is reflux stirring at 50-90℃, the stirring time is 1-24h, and the stirring speed is 200-500rpm.

[0019] Further, in step 2), the mineralizer is a fluoride salt.

[0020] Further, the fluoride salt can be selected from one or more of ammonium fluoride, sodium fluoride, potassium fluoride, calcium fluoride, magnesium fluoride, etc.

[0021] Further, in step 2), the complexing agent is an organic compound that can bind to nano-silicate particles, and can be selected from one or more of disodium ethylenediaminetetraacetate, o-dihydroxybenzene, m-dihydroxybenzene, p-dihydroxybenzene, phenol, etc.

[0022] Further, in step 2), the microwave stirring temperature is 50-90℃, the stirring time is 0.5-4h, the stirring speed is 500-1000rpm, and the microwave power is 300-600W.

[0023] Further, in step 3), in the crystallization solution, the molar ratio of the template agent, the silicon source, the aluminum source, the fluoride in the mineralizer, the complexing agent, and water is (0.05-0.45):1:(0.01-0.4):(0.005-0.2):(0.01-0.2):(10-60).

[0024] Further, in step 3), the molar ratio of the crystallization solution is (0.05-0.45) template agent:SiO2:(0.005-0.2)Al2O3:(0.005-0.2)F - :(0.01-0.2) complexing agent:(10-60) H2O.

[0025] Further, in step 3), the hydrothermal crystallization method is microwave crystallization, and during the crystallization process, a feed pump is used to continuously inject the crystallization solution into a polytetrafluoroethylene reactor with an inner diameter of 10-60mm, a wall thickness of 0.2-1mm, and a length of 1-3m, the crystallization temperature is 90-180℃, the crystallization time is 0.5-4h, and the microwave power is 500-2000W.

[0026] Further, in step 3), the washing is water washing until the pH is 8-9.

[0027] Further, in step 3), the drying temperature is 100-200℃, and the drying time is 2-24h.

[0028] Further, in step 3), the calcination temperature is 450-650℃, and the calcination time is 3-10h.

[0029] The second object of the present invention is to provide a nano-flaky ZSM-5 molecular sieve prepared by the preparation method.

[0030] Furthermore, the nano-sheet-like ZSM-5 molecular sieve has a high degree of crystallinity and no twins on the surface, and its thickness is 10-100 nm.

[0031] Furthermore, the relative crystallinity of the nano-flaky ZSM-5 molecular sieve is ≥95%.

[0032] A third object of the present invention is to provide an application of a nano-flaky ZSM-5 molecular sieve prepared using the preparation method. The nano-flaky ZSM-5 molecular sieve can be used in fields such as isomer separation, methanol-to-olefins, and carbonyl sulfide removal from coal gas. The nano-flaky ZSM-5 molecular sieve can be used in one or more of these applications, exhibiting excellent adsorptive separation and catalytic performance.

[0033] Furthermore, the nano-sheet-like ZSM-5 molecular sieve is loaded with Cu + Then, an adsorbent is obtained, and the adsorbent can be used for adsorption and removal of carbonyl sulfide (COS) in coal gas.

[0034] Furthermore, the adsorbent has a higher sulfur penetration adsorption capacity and better regeneration performance, with a COS penetration adsorption capacity of ≥20 mg / g and a removal rate of ≥95%.

[0035] The fourth object of the present invention is to provide a Cu-loaded + Nano-flaky ZSM-5 molecular sieve, wherein the nano-flaky ZSM-5 molecular sieve is loaded with Cu + get.

[0036] Furthermore, when the nano-sheet ZSM-5 molecular sieve is loaded with Cu + After that, the obtained loaded Cu + The nano-flaky ZSM-5 molecular sieve can be used for the adsorption and removal of carbonyl sulfide in coal gas, with a penetration capacity of ≥20 mg / g and a removal rate of ≥95%.

[0037] The technical concept of the present invention is as follows:

[0038] When F - When the concentration is low, in order to improve its utilization rate, the crystallization liquid can be pretreated by microwave stirring to make F -It is fully dispersed in the crystallization solution, thereby maximizing the promotion of crystal nucleation and guiding the improvement of the template's arrangement efficiency along the ac crystal plane. In the synthesis process of ZSM-5 molecular sieve, only inorganic aluminosilicates can be used as active substances for crystal nucleation growth. After the complexing agent is introduced, it can form a complex with the inorganic aluminosilicates. These complexed aluminosilicates cannot be used as active substances for the growth of crystal nuclei, thereby effectively regulating the concentration of inorganic silicates in the crystallization solution. Under high temperature conditions, the complexed aluminosilicates can slowly decompose and release inorganic aluminosilicates, so that the inorganic aluminosilicate content in the crystallization solution is always maintained at a low concentration, achieving the purpose of guiding the directional growth of ZSM-5 molecular sieve. Compared with the growth rate in the b-axis direction, the growth rate in the ac-axis direction is faster, especially the growth rate in the c-axis direction is the fastest. Under the condition of relatively low inorganic aluminosilicate concentration, almost all active aluminosilicate is used for growth in the c-axis direction, thereby achieving the purpose of suppressing growth in the b-axis direction, and finally obtaining nano-flaky ZSM-5 (MFI type) molecular sieve. In addition, under this condition, the formation of new crystal nuclei during the crystallization process is also suppressed, solving the problem of twins generated by the deposition of new crystal nuclei on the b-face growth. Further, by introducing microwave crystallization, the rapid synthesis of nano-flaky MFI type molecular sieves is achieved, and by modifying the structure of the reactor, microwave continuous hydrothermal crystallization is achieved to prepare nano-flaky MFI type molecular sieves. Based on the above method, the nano-flaky MFI type molecular sieve is finally achieved at low concentrations of F - Nano-thin sheet MFI molecular sieves with high crystallinity, no surface twins and a thickness of 10-100 nm were prepared by continuous and rapid hydrothermal crystallization under certain conditions.

[0039] Compared with the prior art, the present invention has the following characteristics:

[0040] 1) Compared with the existing nano-thin sheet ZSM-5 molecular sieve preparation technology, the present invention uses a complexing agent to assist F - The crystallization method realizes the - The introduction of microwave technology in the pretreatment process of crystallization solution significantly improved the performance of low concentration F - The distribution uniformity in the crystallization liquid, the fully distributed F -This maximizes the promotion of nucleation and guides the efficient arrangement of the template along the ac crystal plane. The introduced complexing agent tightly binds to the inorganic aluminosilicate, effectively regulating the concentration of inorganic silicates in the crystallization solution. Its slow decomposition and release under high temperature conditions consistently maintains a low concentration of inorganic aluminosilicate in the crystallization solution. At low concentrations, nearly all of the active aluminosilicate is used for growth along the c-axis, significantly suppressing growth along the b-axis. This also inhibits the formation of new nuclei during the crystallization process, resolving the problem of twinning caused by the deposition of new nuclei on the b-plane. Ultimately, the preparation of twin-free nano-sheet ZSM-5 molecular sieve is achieved.

[0041] 2) Compared with the existing nano-flaky ZSM-5 molecular sieve preparation technology, the present invention realizes the preparation of nano-flaky ZSM-5 molecular sieve by microwave hydrothermal crystallization. By designing and modifying the reactor structure, it is possible to achieve the following results at low concentrations of F - Nano-flaky MFI molecular sieves with high crystallinity, no surface twins, and a thickness of 10-100 nm are prepared by continuous and rapid hydrothermal crystallization under certain conditions, which greatly improves the synthesis efficiency of nano-flaky ZSM-5 molecular sieves.

[0042] 3) Compared with the existing nano-flaky ZSM-5 molecular sieve preparation technology, the nano-flaky ZSM-5 molecular sieve prepared by the present invention exhibits better adsorption and catalytic performance when applied to the fields of isomer separation, methanol to olefins, and coal gas carbonyl sulfide removal. + After that, the obtained adsorbent has a higher sulfur penetration adsorption capacity and better regeneration performance, and its COS penetration adsorption capacity is ≥20mg / g and the removal rate is ≥95%.

[0043] 4) The preparation method for the nano-flaky ZSM-5 molecular sieve proposed in the present invention is simple to operate, has high synthesis efficiency, good stability and repeatability, and is suitable and easy for industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 The XRD spectrum of the nano-flaky ZSM-5 molecular sieve prepared in Example 1 is shown in FIG.

[0045] Figure 2 This is an SEM image of the nano-flaky ZSM-5 molecular sieve prepared in Example 1;

[0046] Figure 3 The XRD spectrum of the nano-flaky ZSM-5 molecular sieve prepared in Example 2 is shown in FIG.

[0047] Figure 4 This is an SEM image of the nano-flaky ZSM-5 molecular sieve prepared in Example 2;

[0048] Figure 5 The XRD spectrum of the nano-flaky ZSM-5 molecular sieve prepared in Example 3 is shown in FIG.

[0049] Figure 6 This is an SEM image of the nano-flaky ZSM-5 molecular sieve prepared in Example 3;

[0050] Figure 7 This is an SEM image of the nano-flaky ZSM-5 molecular sieve prepared in Example 4;

[0051] Figure 8 This is an SEM image of the nano-flaky ZSM-5 molecular sieve prepared in Example 5;

[0052] Figure 9 This is the SEM image of the ZSM-5 molecular sieve prepared in Comparative Example 1. DETAILED DESCRIPTION

[0053] The present invention is described in detail below with reference to specific embodiments, but is by no means intended to limit the present invention. Any features, such as preparation methods, materials, structures, or composition ratios, that are not explicitly described in this technical solution are considered to be common technical features disclosed in the prior art.

[0054] The present invention provides a nano-flaky ZSM-5 molecular sieve and its preparation method and application. The preparation method comprises the following steps:

[0055] 1) Adding a silicon source and an aluminum source to a template and water, stirring evenly to obtain a crystallization liquid precursor;

[0056] 2) adding a certain amount of mineralizer and complexing agent to the crystallization liquid precursor, and stirring the mixture uniformly by microwave to obtain a crystallization liquid;

[0057] 3) The crystallization liquid is placed in a reactor for closed crystallization to obtain nano-sheet-like ZSM-5 molecular sieve.

[0058] Compared with the prior art, the present invention realizes low concentration F - The high crystallinity nano-sheet ZSM-5 molecular sieve was prepared by continuous and rapid hydrothermal crystallization under the conditions, which greatly reduced the high concentration of F - The use of ZSM-5 molecular sieves has caused great harm to the environment. In addition, a nano-thin sheet ZSM-5 molecular sieve with no twins and a thickness of 10-100 nm is prepared. For the removal of carbonyl sulfide in coal gas, the nano-thin sheet ZSM-5 molecular sieve prepared by the present invention is loaded with Cu + Finally, it has higher COS penetration adsorption capacity and removal rate, and better regeneration performance.

[0059] In the following examples, unless otherwise specified, the reagents used are conventional commercially available products, and the methods employed are well known in the art.

[0060] In the following examples, pseudo-boehmite was purchased from Chinalco Shandong Co., Ltd., model number PDF-07. Coffin-shaped ZSM-5 molecular sieve was purchased from Fuyu (Zhangjiagang) New Materials Co., Ltd., model number SAR-40S.

[0061] Example 1

[0062] This embodiment provides a method for preparing nano-flaky ZSM-5 molecular sieve, comprising the following steps:

[0063] 1) Preparation of Crystallization Liquid Precursor: A crystallization liquid precursor was prepared according to a molar ratio of 0.05 template: 1 silicon from the silicon source: 0.01 aluminum from the aluminum source: 10 H2O. 40.6 g of TPAOH (25 wt% aqueous solution), 211.5 g of tetraethyl orthosilicate, and 149.7 g of deionized water were weighed and mixed to obtain a transparent solution. 0.515 g of pseudo-boehmite was then slowly added to the transparent solution. After stirring at room temperature for 1 hour, the solution was heated to 50°C and refluxed with stirring for 12 hours at 300 rpm to obtain the crystallization liquid precursor.

[0064] 2) Preparation of crystallization solution: The molar ratio is 0.05 template agent: 1 silicon in silicon source: 0.01 aluminum in aluminum source: 0.2 fluorine (F) in mineralizer. - A crystallization solution was prepared using a ratio of 0.2 complexing agent to 10 H2O. 7.42 g of ammonium fluoride was weighed and added to the above crystallization solution precursor, followed by reflux at 50°C with microwave stirring (500 rpm) for 4 h at a microwave power of 300 W. After uniform stirring, 22.0 g of hydroquinone was added, and the mixture was stirred under microwave reflux at 50°C for 1 h to obtain a crystallization solution.

[0065] 3) Hydrothermal crystallization: The crystallization solution obtained in step 2) was pumped into a polytetrafluoroethylene reactor with an inner diameter of 10 mm, a wall thickness of 0.2 mm, and a length of 1 m using a feed pump. The feed rate of the feed pump was adjusted so that the residence time of the crystallization solution in the constant temperature zone of 90° C. was 4 h. Microwave crystallization was performed with a microwave power of 500 W. After separation, the solution was washed with deionized water to a pH of 8-9, dried at 100° C. for 8 h, and calcined at 450° C. for 10 h. After cooling, nano-flaky ZSM-5 molecular sieves were prepared.

[0066] The phase structure and morphology of the nano-thin sheet ZSM-5 molecular sieve prepared above were analyzed. Figure 1 and 2 Analysis shows that the prepared ZSM-5 molecular sieve is pure phase, has a relative crystallinity of 98.4%, has no surface twins and is in the form of flakes with a thickness of 80-100 nm.

[0067] Example 2

[0068] This embodiment provides a method for preparing nano-flaky ZSM-5 molecular sieve, comprising the following steps:

[0069] 1) Preparation of Crystallization Liquid Precursor: A crystallization liquid precursor was prepared according to a molar ratio of 0.25 template: 1 silicon from the silicon source: 0.01 aluminum from the aluminum source: 10 H2O. 203.3 g of TPAOH (25 wt% aqueous solution), 211.5 g of tetraethyl orthosilicate, and 27.7 g of deionized water were weighed and mixed to obtain a transparent solution. 0.515 g of pseudo-boehmite was then slowly added to the transparent solution. After stirring at room temperature for 1 hour, the solution was heated to 90°C and refluxed with stirring for 4 hours at 300 rpm to obtain the crystallization liquid precursor.

[0070] 2) Preparation of crystallization solution: The molar ratio is 0.25 template agent: 1 silicon in silicon source: 0.01 aluminum in aluminum source: 0.1 fluorine (F) in mineralizer. - A crystallization solution was prepared by mixing 3.7 g of ammonium fluoride and 270 g of deionized water. The mixture was then added to the crystallization solution precursor and refluxed at 90°C for 0.5 h under microwave stirring (1000 rpm) with a microwave power of 500 W. After uniform stirring, 11.0 g of hydroquinone was added and the mixture was stirred at 90°C for 1 h under microwave reflux to obtain a crystallization solution.

[0071] 3) Hydrothermal crystallization: The crystallization solution obtained in step 2) was pumped into a polytetrafluoroethylene reactor with an inner diameter of 10 mm, a wall thickness of 0.2 mm, and a length of 1 m using a feed pump. The feed rate of the feed pump was adjusted so that the residence time of the crystallization solution in the constant temperature zone of 90° C. was 4 h. Microwave crystallization was performed with a microwave power of 1000 W. After separation, the solution was washed with deionized water to a pH of 8-9, dried at 100° C. for 8 h, and calcined at 650° C. for 3 h. After cooling, nano-flaky ZSM-5 molecular sieves were prepared.

[0072] The phase structure and morphology of the nano-thin sheet ZSM-5 molecular sieve prepared above were analyzed. Figure 3 and 4 Analysis shows that the prepared ZSM-5 molecular sieve is pure phase, has a relative crystallinity of 97.2%, has no surface twins and is in the form of flakes with a thickness of 60-80 nm.

[0073] Example 3

[0074] This embodiment provides a method for preparing nano-flaky ZSM-5 molecular sieve, comprising the following steps:

[0075] 1) Preparation of Crystallization Liquid Precursor: A crystallization liquid precursor was prepared according to a molar ratio of 0.05 template: 1 silicon from the silicon source: 0.01 aluminum from the aluminum source: 10 H2O. 40.6 g of TPAOH (25 wt% aqueous solution), 211.5 g of tetraethyl orthosilicate, and 149.7 g of deionized water were weighed and mixed to obtain a transparent solution. 0.515 g of pseudo-boehmite was then slowly added to the transparent solution. After stirring at room temperature for 1 hour, the solution was heated to 50°C and refluxed with stirring for 12 hours at 500 rpm to obtain the crystallization liquid precursor.

[0076] 2) Preparation of crystallization solution: The molar ratio is 0.05 template agent: 1 silicon in silicon source: 0.01 aluminum in aluminum source: 0.2 fluorine (F) in mineralizer. - A crystallization solution was prepared by mixing 0.2 complexing agent and 10 H2O. 7.42 g of ammonium fluoride was weighed and added to the above crystallization solution precursor, followed by reflux at 50°C with microwave stirring (700 rpm) for 4 h at a microwave power of 400 W. After uniform stirring, 22.0 g of catechol was added, and the mixture was further stirred at 50°C with microwave reflux for 1 h to obtain a crystallization solution.

[0077] 3) Hydrothermal crystallization: The crystallization solution obtained in step 2) was pumped into a polytetrafluoroethylene reactor with an inner diameter of 60 mm, a wall thickness of 1 mm, and a length of 3 m using a feed pump. The feed rate of the feed pump was adjusted so that the residence time of the crystallization solution in the constant temperature zone of 180° C. was 0.5 h. Microwave crystallization was performed with a microwave power of 1200 W. After separation, the product was washed with deionized water to a pH of 8-9, dried at 150° C. for 4 h, and calcined at 550° C. for 6 h. After cooling, nano-flaky ZSM-5 molecular sieves were prepared.

[0078] The phase structure and morphology of the nano-thin sheet ZSM-5 molecular sieve prepared above were analyzed. Figure 5 and 6 Analysis shows that the prepared ZSM-5 molecular sieve is pure phase, has a relative crystallinity of 99.6%, has no surface twins and is in the form of flakes with a thickness of 90-100 nm.

[0079] Example 4

[0080] This embodiment provides a method for preparing nano-flaky ZSM-5 molecular sieve, comprising the following steps:

[0081] 1) Preparation of Crystallization Liquid Precursor: A crystallization liquid precursor was prepared according to a molar ratio of 0.25 template agent: 1 silicon from the silicon source: 0.1 aluminum from the aluminum source: 10 H2O. 203.3 g of TEAH (25 wt% aqueous solution), 211.5 g of tetraethyl orthosilicate, and 27.7 g of deionized water were weighed and mixed to obtain a transparent solution. 7.92 g of aluminum hydroxide was then weighed and added to the transparent solution. After stirring at room temperature for 1 hour, the solution was heated to 90°C and refluxed with stirring for 4 hours at 300 rpm to obtain the crystallization liquid precursor.

[0082] 2) Preparation of crystallization solution: The molar ratio is 0.25 template agent: 1 silicon in silicon source: 0.1 aluminum in aluminum source: 0.1 fluorine (F) in mineralizer. - A crystallization solution was prepared by mixing 3.7 g of ammonium fluoride and 270 g of deionized water. The mixture was then added to the crystallization solution precursor and refluxed at 90°C for 0.5 h under microwave stirring (500 rpm) with a microwave power of 600 W. After uniform stirring, 16.5 g of resorcinol was added and the mixture was stirred at 90°C for 1 h under microwave reflux to obtain a crystallization solution.

[0083] 3) Hydrothermal crystallization: The crystallization solution obtained in step 2) was pumped into a polytetrafluoroethylene reactor with an inner diameter of 30 mm, a wall thickness of 0.5 mm, and a length of 2 m using a feed pump. The feed rate of the feed pump was adjusted so that the residence time of the crystallization solution in the constant temperature zone of 90° C. was 4 h. Microwave crystallization was performed with a microwave power of 800 W. After separation, the solution was washed with deionized water to a pH of 8-9, dried at 100° C. for 8 h, and calcined at 550° C. for 6 h. After cooling, nano-flaky ZSM-5 molecular sieves were prepared.

[0084] The morphology of the nano-thin sheet ZSM-5 molecular sieve prepared above was analyzed. Figure 7 Analysis shows that the prepared ZSM-5 molecular sieve is 85-100 nm thick and has no surface twins, and a relative crystallinity of 96.9%.

[0085] Example 5

[0086] This embodiment provides a method for preparing nano-flaky ZSM-5 molecular sieve, comprising the following steps:

[0087] 1) Preparation of Crystallization Liquid Precursor: A crystallization liquid precursor was prepared according to a molar ratio of 0.1 template: 1 silicon from the silicon source: 0.02 aluminum from the aluminum source: 30 H2O. 26.9 g of TPABr, 211.5 g of tetraethyl orthosilicate, and 540.6 g of deionized water were weighed and mixed to obtain a transparent solution. 1.03 g of pseudoboehmite was then slowly added to the transparent solution. After stirring at room temperature for 1 hour, the solution was heated to 90°C and refluxed with stirring for 12 hours at 300 rpm to obtain the crystallization liquid precursor.

[0088] 2) Preparation of crystallization solution: The molar ratio is 0.1 template agent: 1 silicon in silicon source: 0.02 aluminum in aluminum source: 0.2 fluorine (F) in mineralizer. - Prepare a crystallization solution with a ratio of 0.1 complexing agent: 60H2O. Mix 7.4g of ammonium fluoride and 360g of deionized water, then add it to the above crystallization solution precursor, continue to stir and reflux at 90°C for 2h, microwave power 400W. After stirring, add 11.0g of catechol, continue stirring at 90°C for 1h to obtain a crystallization solution;

[0089] 3) Hydrothermal crystallization: The crystallization solution obtained in step 2) was pumped into a polytetrafluoroethylene reactor with an inner diameter of 60 mm, a wall thickness of 1 mm, and a length of 3 m using a feed pump. The feed rate of the feed pump was adjusted so that the residence time of the crystallization solution in the constant temperature zone of 180° C. was 0.5 h. Microwave crystallization was performed with a microwave power of 2000 W. After separation, the product was washed with deionized water to a pH of 8-9, dried at 150° C. for 4 h, and calcined at 550° C. for 6 h. After cooling, nano-flaky ZSM-5 molecular sieves were prepared.

[0090] The morphology of the nano-thin sheet ZSM-5 molecular sieve prepared above was analyzed. Figure 8 Analysis shows that the prepared ZSM-5 molecular sieve is a thin sheet with no twins on the surface and a thickness of 40-60 nm, and its relative crystallinity is 98.1%.

[0091] Example 6

[0092] This embodiment provides an application of a nano-flaky ZSM-5 molecular sieve, comprising the following steps:

[0093] The nano-flaky ZSM-5 molecular sieve prepared in Example 1 was mixed with a 0.1 mol / L cuprous chloride aqueous solution at a solid-liquid ratio of 1:3, stirred at 80°C (500 rpm) for 4 h, separated, washed, dried (120°C / 6 h) and calcined (500°C / 3 h) to obtain Cu 2+ -ZSM-5 molecular sieve. Using 5% CO / 95% N2 mixed gas to 2+-ZSM-5 molecular sieve is reduced and reduced at 220℃ for 2h to obtain Cu + -ZSM-5 molecular sieve (loaded Cu + Nano-flaky ZSM-5 molecular sieve).

[0094] The nano-thin ZSM-5 molecular sieve was replaced with the commonly used coffin-shaped ZSM-5 molecular sieve, and the Cu + - Preparation of ZSM-5 molecular sieve to obtain loaded Cu + Coffin-shaped ZSM-5 molecular sieve.

[0095] The raw gas is simulated coal gas, which consists of hydrogen (59%), methane (25%), carbon monoxide (5%), nitrogen (2%), carbon dioxide (3%), oxygen (3%), ethane (0.7%), ethylene (2.1%), propylene (0.2%), and a COS content of 200 ppm. The gas pressure is 0.1 MPa, the adsorption temperature is 20°C, and the space velocity is 1000 h -1 , the two Cu + -ZSM-5 molecular sieve (pressed and crushed and sieved with 10-30 mesh) COS penetration adsorption capacity (with the outlet content exceeding 10ppm as the penetration point) was tested. The results showed that the loaded Cu + The COS penetration adsorption capacity of the nano-thin ZSM-5 molecular sieve is 23.1 mg / g, and the removal rate reaches 96.2%; the loaded Cu + The COS penetration adsorption capacity of the coffin-shaped ZSM-5 molecular sieve is 10.5 mg / g, and the removal rate is 90.1%. + The nano-flaky ZSM-5 molecular sieve has better COS removal performance.

[0096] Example 7

[0097] This embodiment provides an application of a nano-flaky ZSM-5 molecular sieve, comprising the following steps:

[0098] The nano-flaky ZSM-5 molecular sieve prepared in Example 2 was mixed with a 0.1 mol / L cuprous chloride aqueous solution at a solid-liquid ratio of 1:3, stirred at 80°C (500 rpm) for 4 h, separated, washed, dried (120°C / 6 h) and calcined (500°C / 3 h) to obtain Cu 2+ -ZSM-5 molecular sieve. Using 5% CO / 95% N2 mixed gas to 2+ -ZSM-5 molecular sieve is reduced and reduced at 220℃ for 2h to obtain Cu + -ZSM-5 molecular sieve (loaded Cu +Nano-flaky ZSM-5 molecular sieve).

[0099] The nano-thin ZSM-5 molecular sieve was replaced with the commonly used coffin-shaped ZSM-5 molecular sieve, and the Cu + - Preparation of ZSM-5 molecular sieve to obtain loaded Cu + Coffin-shaped ZSM-5 molecular sieve.

[0100] The raw gas is simulated coal gas, which consists of hydrogen (59%), methane (25%), carbon monoxide (5%), nitrogen (2%), carbon dioxide (3%), oxygen (3%), ethane (0.7%), ethylene (2.1%), propylene (0.2%), and a COS content of 200 ppm. The gas pressure is 0.1 MPa, the adsorption temperature is 20°C, and the space velocity is 1000 h -1 , the two Cu + -ZSM-5 molecular sieve (pressed and crushed and sieved with 10-30 mesh) COS penetration adsorption capacity (with the outlet content exceeding 10ppm as the penetration point) was tested. The results showed that the loaded Cu + The COS penetration adsorption capacity of the nano-thin ZSM-5 molecular sieve is 21.2 mg / g, and the removal rate is 95.8%; the loaded Cu + The COS penetration adsorption capacity of the coffin-shaped ZSM-5 molecular sieve is 11.9 mg / g, and the removal rate reaches 91.3%. + The nano-flaky ZSM-5 molecular sieve has better COS removal performance.

[0101] Example 8

[0102] This embodiment provides an application of a nano-flaky ZSM-5 molecular sieve, comprising the following steps:

[0103] The nano-flaky ZSM-5 molecular sieve prepared in Example 3 was mixed with a 0.1 mol / L cuprous chloride aqueous solution at a solid-liquid ratio of 1:3, stirred at 80°C (500 rpm) for 4 h, separated, washed, dried (120°C / 6 h) and calcined (500°C / 3 h) to obtain Cu 2+ -ZSM-5 molecular sieve. Using 5% CO / 95% N2 mixed gas to 2+ -ZSM-5 molecular sieve is reduced and reduced at 220℃ for 2h to obtain Cu + -ZSM-5 molecular sieve (loaded Cu + Nano-flaky ZSM-5 molecular sieve).

[0104] The nano-thin ZSM-5 molecular sieve was replaced with the commonly used coffin-shaped ZSM-5 molecular sieve, and the Cu + - Preparation of ZSM-5 molecular sieve to obtain loaded Cu + Coffin-shaped ZSM-5 molecular sieve.

[0105] The raw gas is simulated coal gas, which consists of hydrogen (59%), methane (25%), carbon monoxide (5%), nitrogen (2%), carbon dioxide (3%), oxygen (3%), ethane (0.7%), ethylene (2.1%), propylene (0.2%), and a COS content of 200 ppm. The gas pressure is 0.1 MPa, the adsorption temperature is 20°C, and the space velocity is 1000 h -1 , the two Cu + -ZSM-5 molecular sieve (pressed and crushed and sieved with 10-30 mesh) COS penetration adsorption capacity (with the outlet content exceeding 10ppm as the penetration point) was tested. The results showed that the loaded Cu + The COS penetration adsorption capacity of the nano-thin ZSM-5 molecular sieve is 20.5 mg / g, and the removal rate reaches 96.5%; the loaded Cu + The COS penetration adsorption capacity of the coffin-shaped ZSM-5 molecular sieve is 10.7 mg / g, and the removal rate reaches 89.2%. + The nano-flaky ZSM-5 molecular sieve has better COS removal performance.

[0106] Comparative Example 1

[0107] This comparative example provides a method for preparing a ZSM-5 molecular sieve, comprising the following steps:

[0108] 1) Preparation of Crystallization Liquid Precursor: A crystallization liquid precursor was prepared according to a molar ratio of 0.05 template: 1 silicon from the silicon source: 0.01 aluminum from the aluminum source: 10 H2O. 40.6 g of TPAOH (25 wt% aqueous solution), 211.5 g of tetraethyl orthosilicate, and 149.7 g of deionized water were weighed and mixed to obtain a transparent solution. 0.515 g of pseudo-boehmite was then slowly added to the transparent solution. After stirring at room temperature for 1 hour, the solution was heated to 50°C and refluxed with stirring for 12 hours at 300 rpm to obtain the crystallization liquid precursor.

[0109] 2) Crystallization Solution Preparation: A crystallization solution was prepared at a molar ratio of 0.05 template agent: 1 silicon from the silicon source: 0.01 aluminum from the aluminum source: 0.2 complexing agent: 10 H2O. The crystallization solution precursor was refluxed at 50°C with microwave stirring (500 rpm) for 4 h at a microwave power of 300 W. 22.0 g of hydroquinone was then added, and the mixture was refluxed at 50°C with microwave stirring for 1 h to obtain the crystallization solution.

[0110] 3) Hydrothermal crystallization: The crystallization solution obtained in step 2) was pumped into a polytetrafluoroethylene reactor with an inner diameter of 10 mm, a wall thickness of 0.2 mm, and a length of 1 m using a feed pump. The feed rate of the feed pump was adjusted so that the residence time of the crystallization solution in the constant temperature zone of 90° C. was 4 h. Microwave crystallization was performed with a microwave power of 500 W. After separation, the solution was washed with deionized water to a pH of 8-9, dried at 100° C. for 8 h, and calcined at 450° C. for 10 h. After cooling, the ZSM-5 molecular sieve was prepared.

[0111] like Figure 9 As shown in the figure, the coffin-shaped ZSM-5 molecular sieve with a large number of twins on the surface is prepared. The nano-sheet-shaped ZSM-5 molecular sieve in Example 6 is replaced with the ZSM-5 molecular sieve of this comparative example, and the Cu + - Preparation of ZSM-5 molecular sieve to obtain loaded Cu + ZSM-5 molecular sieve.

[0112] The same test as in Example 6 was carried out, and the results showed that the Cu + The COS penetration adsorption capacity of ZSM-5 molecular sieve is 8.7 mg / g, and the removal rate reaches 74.8%.

[0113] Compared with Example 1, this comparative example did not obtain a flaky ZSM-5 molecular sieve, and the Cu + The COS penetration adsorption capacity of ZSM-5 molecular sieve is low and the removal rate is poor.

[0114] Comparative Example 2

[0115] This comparative example provides a method for preparing a ZSM-5 molecular sieve, comprising the following steps:

[0116] 1) Preparation of Crystallization Liquid Precursor: A crystallization liquid precursor was prepared according to a molar ratio of 0.05 template: 1 silicon from the silicon source: 0.01 aluminum from the aluminum source: 10 H2O. 40.6 g of TPAOH (25 wt% aqueous solution), 211.5 g of tetraethyl orthosilicate, and 149.7 g of deionized water were weighed and mixed to obtain a transparent solution. 0.515 g of pseudo-boehmite was then slowly added to the transparent solution. After stirring at room temperature for 1 hour, the solution was heated to 50°C and refluxed with stirring for 12 hours at 300 rpm to obtain the crystallization liquid precursor.

[0117] 2) Preparation of crystallization solution: The molar ratio is 0.05 template agent: 1 silicon in silicon source: 0.01 aluminum in aluminum source: 0.2 fluorine (F) in mineralizer. -):0.2 complexing agent:10 H2O. 7.42 g of ammonium fluoride was weighed into the above crystallization liquid precursor, and then stirred (500 rpm) at 50 °C for 4 h under reflux. After uniform stirring, 22.0 g of hydroquinone was added, and the crystallization liquid was obtained after stirring at 50 °C for 1 h under reflux;

[0118] 3) Hydrothermal crystallization: the crystallization liquid obtained in step 2) was pumped into a polytetrafluoroethylene reactor with an inner diameter of 10 mm, a wall thickness of 0.2 mm, and a length of 1 m using a feed pump. The residence time of the crystallization liquid in the constant-temperature zone at 90 °C was 4 h by adjusting the feed rate of the feed pump. Microwave crystallization was performed at a microwave power of 500 W. After separation, the product was washed with deionized water until the pH was 8-9, dried at 100 °C for 8 h, calcined at 450 °C for 10 h, and then cooled to obtain ZSM-5 molecular sieves.

[0119] The same test as in Example 6 was performed, and the results showed that the COS breakthrough adsorption capacity of the Cu + -loaded ZSM-5 molecular sieves of the present comparative example was 10.1 mg / g, and the removal rate reached 74.8%.

[0120] Compared with Example 1, the COS breakthrough adsorption capacity of the Cu + -loaded ZSM-5 molecular sieves prepared in the present comparative example was lower, and the removal rate was poorer.

[0121] Comparative Example 3

[0122] The present comparative example provides a method for preparing ZSM-5 molecular sieves, comprising the following steps:

[0123] 1) Crystallization liquid precursor preparation: a crystallization liquid precursor was prepared according to a molar ratio of 0.05 template: 1 silicon in the silicon source: 0.01 aluminum in the aluminum source: 10 H2O. 40.6 g of TPAOH (25 wt% aqueous solution), 211.5 g of tetraethyl orthosilicate, and 149.7 g of deionized water were mixed uniformly to obtain a transparent solution. Then, 0.515 g of pseudoboehmite was slowly added to the transparent solution, and the above solution was stirred at room temperature for 1 h. Then, the solution was heated to 50 °C and stirred under reflux for 12 h at a stirring speed of 300 rpm, to obtain a crystallization liquid precursor;

[0124] 2) Crystallization liquid preparation: a crystallization liquid was prepared according to a molar ratio of 0.05 template: 1 silicon in the silicon source: 0.01 aluminum in the aluminum source: 0.2 fluorine (F - ) in the mineralizer: 0.2 complexing agent: 10 H2O. 7.42 g of ammonium fluoride was weighed into the above crystallization liquid precursor, and then stirred (500 rpm) at 50 °C for 4 h under reflux. After uniform stirring, 22.0 g of hydroquinone was added, and the crystallization liquid was obtained after stirring at 50 °C for 1 h under reflux;

[0125] 3) Hydrothermal crystallization: The crystallization solution obtained in step 2) was pumped into a polytetrafluoroethylene reactor with an inner diameter of 100 mm, a wall thickness of 10 mm, and a length of 0.5 m using a feed pump. The feed rate of the feed pump was adjusted so that the residence time of the crystallization solution in the constant temperature zone of 90° C. was 4 h. Microwave crystallization was performed with a microwave power of 500 W. After separation, the solution was washed with deionized water to a pH of 8-9, dried at 100° C. for 8 h, and calcined at 450° C. for 10 h. After cooling, the ZSM-5 molecular sieve was prepared.

[0126] The same test as in Example 6 was carried out, and the results showed that the Cu + The COS penetration adsorption capacity of ZSM-5 molecular sieve is 9.4 mg / g, and the removal rate reaches 71.1%.

[0127] Compared with Example 1, the Cu-loaded + The COS penetration adsorption capacity of ZSM-5 molecular sieve is low and the removal rate is poor.

[0128] The above description of the embodiments is intended to facilitate understanding and use of the invention by those skilled in the art. It will be apparent that those skilled in the art can readily make various modifications to these embodiments and apply the general principles described herein to other embodiments without requiring inventive effort. Therefore, the present invention is not limited to the above-described embodiments. Improvements and modifications made by those skilled in the art based on the disclosure of the present invention, without departing from the scope of the present invention, should be within the scope of protection of the present invention.

Claims

1. A method for preparing nano-flaky ZSM-5 molecular sieve, characterized in that: The preparation method of the nano-flaky ZSM-5 molecular sieve comprises the following steps: 1) Adding a silicon source and an aluminum source to a template and water, stirring evenly to obtain a crystallization liquid precursor; 2) adding a mineralizer mixture or a mineralizer to the crystallization solution precursor obtained in step 1), stirring the mixture uniformly under microwave conditions, then adding a complexing agent, and continuing to stir the mixture under microwave conditions to obtain a crystallization solution, wherein the mineralizer mixture is a mixture obtained by dissolving the mineralizer in water; 3) subjecting the crystallization solution obtained in step 2) to closed hydrothermal crystallization, followed by separation, washing, drying and calcination to obtain nano-flaky ZSM-5 molecular sieve; In step 2), the mineralizer is a fluorine-containing compound, and the complexing agent is one or more of disodium ethylenediaminetetraacetic acid or a benzene derivative containing a phenolic hydroxyl group.

2. The method for preparing nano-flaky ZSM-5 molecular sieve according to claim 1, characterized in that: In step 1), the template and water are first mixed uniformly, and then the aluminum source is added. After the aluminum source is dissolved, the silicon source is added; In step 1), in the crystallization liquid precursor, the molar ratio of the template, the silicon in the silicon source, the aluminum in the aluminum source, and water is (0.05-0.45):1:(0.01-0.4):(10-30); In step 1), the silicon source is selected from one or more of silicon dioxide, silicon powder, solid silica gel, ammonium fluorosilicate, white carbon black, silica sol and tetraethyl orthosilicate; The template agent is selected from one or more of tetrapropylammonium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetraethylammonium bromide, tetrapropylammonium bromide, n-butylamine, n-propylamine, and ethylenediamine; In step 1), the aluminum source is selected from one or more of alumina, pseudo-boehmite, aluminum hydroxide, aluminum isopropoxide, aluminum sulfate, and aluminum chloride.

3. The method for preparing nano-flaky ZSM-5 molecular sieve according to claim 1, characterized in that: In step 1), the uniform stirring is performed by stirring under reflux at 50-90° C., the stirring time is 1-24 h, and the stirring speed is 200-500 rpm.

4. The method for preparing nano-flaky ZSM-5 molecular sieve according to claim 1, characterized in that: In step 2), the mineralizer is a fluoride salt; The fluoride salt is selected from one or more of ammonium fluoride, sodium fluoride, potassium fluoride, calcium fluoride and magnesium fluoride; In step 2), the complexing agent is selected from one or more of disodium edetate, catechol, resorcinol, hydroquinone, and phenol.

5. The method for preparing nano-flaky ZSM-5 molecular sieve according to claim 1, characterized in that: In step 2), the microwave stirring temperature is 50-90° C., the stirring time is 0.5-4 h, the stirring speed is 500-1000 rpm, and the microwave power is 300-600 W.

6. The method for preparing nano-flaky ZSM-5 molecular sieve according to claim 1, characterized in that: In step 3), in the crystallization solution, the molar ratio of the template, silicon source, aluminum source, fluorine in the mineralizer, complexing agent, and water is (0.05-0.45):1:(0.01-0.4):(0.005-0.2):(0.01-0.2):(10-60).

7. The method for preparing nano-flaky ZSM-5 molecular sieve according to claim 1, characterized in that: In step 3), the hydrothermal crystallization method is microwave crystallization. During the crystallization process, a feed pump is used to continuously inject the crystallization liquid into a polytetrafluoroethylene reactor with an inner diameter of 10-60 mm, a wall thickness of 0.2-1 mm, and a length of 1-3 m. The crystallization temperature is 90-180° C., the crystallization time is 0.5-4 h, and the microwave power is 500-2000 W; In step 3), the washing is performed with water until the pH is 8-9; In step 3), the drying temperature is 100-200° C. and the drying time is 2-24 hours; In step 3), the calcination temperature is 450-650° C. and the calcination time is 3-10 hours.

8. A nano-flaky ZSM-5 molecular sieve prepared by the preparation method according to any one of claims 1 to 7, characterized in that: The nano-sheet-like ZSM-5 molecular sieve has a thickness of 10-100 nm, has no twins on the surface, and has a relative crystallinity of ≥95%.

9. An application of a nano-flaky ZSM-5 molecular sieve prepared by the preparation method according to any one of claims 1 to 7, characterized in that: The nano-flaky ZSM-5 molecular sieve is applied to one or more of coal gas carbonyl sulfide removal, isomer separation and methanol to olefins.

10. A Cu-loaded + Nano-flaky ZSM-5 molecular sieve, prepared by the method according to any one of claims 1 to 7, and loaded with Cu + It is characterized by that When the nano-thin ZSM-5 molecular sieve is loaded with Cu + After that, the loaded Cu + The nano-flaky ZSM-5 molecular sieve is used for the adsorption and removal of carbonyl sulfide in coal gas, with a penetration capacity of ≥20 mg / g and a removal rate of ≥95%.

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