High-efficiency molecular sieve adsorbent for deep purification of oxides and preparation and application thereof

Abstract

The application relates to a high-efficiency molecular sieve adsorbent for deep purification of oxygenates and preparation and application of the adsorbent, and the preparation process comprises the following steps: 1) molecular sieve synthesis: uniformly mixing an aluminum source, a silicon source, alkali, a template agent and water to obtain a crystallization liquid, aging, then carrying out microwave hydrothermal crystallization and traditional hydrothermal crystallization to obtain EMT / 13X mixed crystal molecular sieve, and then carrying out pressure filtration to obtain a wet filter cake; 2) granulation: drying the wet filter cake, uniformly mixing inorganic additives and pore-forming agents, rolling and granulating, and then drying; and 3) calcination: placing the granulated product in an oxygen-containing atmosphere for calcination, so that the EMT / 13X composite molecular sieve adsorbent is obtained. The application breaks through the double-template method for synthesizing the EMT / 13X mixed crystal molecular sieve with an EMT molecular sieve as the main component, complete structure and high crystallinity, the specific surface area of the molecular sieve is greater than or equal to 450 m 2 / g, ethylene adsorption heat is less than or equal to 70 DEG C, the oxygenate adsorption capacity is increased by more than 30%, the purification depth can reach below 1 ppb, and the molecular sieve is suitable for efficient removal of trace nonpolar or polar oxygenates such as dimethyl ether, methanol and propyl aldehyde in low-carbon olefins.

Description

Technical Field

[0001] The invention belongs to the technical field of adsorption material preparation, and relates to a high-efficiency molecular sieve adsorbent for deep purification of oxides, and the preparation and application of the adsorbent. Background Art

[0002] In the polyolefin industry, the method used to remove trace amounts of oxygenates in olefins is molecular sieve adsorption, and the molecular sieve adsorbent used is mostly 13X molecular sieve as the active component. However, in industrial applications, this type of molecular sieve adsorption has a high adsorption heat, and it is easy to produce oligomeric coke during use. In addition, the adsorption capacity of oxygenates adsorbed by this type of molecular sieve is low, and the removal accuracy is only 1ppm, which cannot meet the requirements of high-end polyolefin materials for olefin raw material purity (oxygenate ≤ 0.01ppm), such as metallocene polyethylene. In order to solve the above problems, Zhou Yongxian et al. (Microporous and Mesoporous Materials, 2018, 271: 273-283) were the first to propose the use of EMT molecular sieves with the same FAU structure to remove trace amounts of oxygenates in olefin streams, and developed a molecular sieve adsorbent for deep purification of oxygenates with a larger adsorption capacity, lower purification depth and adsorption heat. However, molecular sieve adsorbents with EMT molecular sieve as the active component can only remove highly polar oxygenates, but cannot remove non-polar or weakly polar oxygenates such as dimethyl ether, resulting in limited application of this type of molecular sieve adsorbent in the purification of olefins derived from the MTO process.

[0003] In view of the fact that 13X molecular sieve can remove non-polar or weakly polar oxygenates, it is proposed to prepare EMT / 13X composite molecular sieve adsorbent and apply it to the deep purification of oxygenates. However, expensive templates are required in the synthesis process of EMT molecular sieve, resulting in high preparation costs. If a dual template can be introduced in the synthesis process of EMT molecular sieve to synthesize EMT / 13X composite molecular sieve with EMT molecular sieve as the main component, it will help to reduce the preparation cost of molecular sieve adsorbent. At present, relevant research reports have been published on the preparation of EMT / 13X composite molecular sieves, but the prepared EMT / 13X composite molecular sieves have small particle size, low crystallinity, and poor heat resistance, and are not suitable for deep purification of oxygenates in olefins.

[0004] For example, Chinese patent ZL 201711259523.8 discloses a method for rapid crystallization synthesis of EMT molecular sieves, in which EMT molecular sieve seeds synthesized under template-free conditions are added to the synthesis system to form a gel. After aging the gel, the EMT molecular sieve is first hydrothermally crystallized for 12 to 72 hours and then crystallized under microwave conditions for 4 to 360 minutes to synthesize the EMT molecular sieve. However, the prepared EMT molecular sieve has low crystallinity and poor heat resistance, which cannot meet the current needs of the industry. SUMMARY

[0005] The present application aims to provide an efficient molecular sieve adsorbent for deep purification of oxygen-containing compounds and its preparation and application, which has larger adsorption capacity, higher purification depth and lower adsorption heat.

[0006] The object of the present application can be achieved by the following technical solutions.

[0007] The EMT / 13X mixed crystal molecular sieve mainly composed of EMT molecular sieve is synthesized by the method of first microwave hydrothermal crystallization and then traditional hydrothermal crystallization under the double-template system with the double-template agent as the structure directing agent, and is applied to the deep purification of oxygen-containing compound impurities in low-carbon olefins. The problem of preparing EMT / 13X mixed crystal molecular sieve with complete structure and high crystallinity by the double-template method is solved, and the way of directly granulating and forming the wet filter cake after pressure filtration is proposed to simplify the traditional process flow and reduce the manufacturing cost, and finally an efficient molecular sieve adsorbent for deep purification of oxygen-containing compounds in olefins is obtained, which has larger adsorption capacity, higher purification depth and lower adsorption heat.

[0008] Specifically, one of the technical solutions of the present application provides a preparation method of an efficient molecular sieve adsorbent for deep purification of oxygen-containing compounds, comprising the following steps:

[0009] (1) uniformly mixing an aluminum source, a silicon source, an alkali source, a template agent and water to obtain a crystallization liquid gel, aging, then microwave hydrothermal crystallization and traditional hydrothermal crystallization to obtain EMT / 13X mixed crystal molecular sieve, and then pressure filtration to obtain a wet filter cake;

[0010] (2) drying the wet filter cake, uniformly mixing after adding inorganic additives and pore-forming agents, rolling granulation and drying;

[0011] (3) placing the dried granulation in an oxygen-containing atmosphere for calcination to obtain an EMT / 13X composite molecular sieve adsorbent, which is the target product.

[0012] Further, the aluminum source is one or more of aluminum hydroxide, sodium metaaluminate, aluminum isopropoxide, aluminum sulfate and butyl aluminum.

[0013] Further, the silicon source is one or more of silica sol, sodium silicate, water glass sodium and tetraethyl orthosilicate, preferably sodium silicate.

[0014] Further, the alkali source is sodium hydroxide.

[0015] Further, the template agent is composed of template agent A and template agent B in a molar ratio of 6:4 to 8:2, wherein the template agent A is 18-crown ether-6 or 15-crown ether-5, and the template agent B is selected from one or more combinations of triethylamine, n-butylamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, polyethylene glycol or polyquaternium-6. Here, the EMT molecular sieve content in the mixed crystal can be reduced by reducing the amount of template agent A.

[0016] Furthermore, the material ratios for synthesizing the EMT / 13X mixed crystal molecular sieve are as follows: a molar ratio of sodium oxide to aluminum oxide of 2 to 10, a molar ratio of silicon oxide to aluminum oxide of 6 to 20, a molar ratio of water to aluminum oxide of 200 to 430, and a molar ratio of template to aluminum oxide of 0.5 to 2.

[0017] Furthermore, in step (1), the aging conditions are: aging time 36 to 96 hours, and aging temperature is room temperature.

[0018] Furthermore, the microwave hydrothermal crystallization conditions are: microwave power of 300-600W, crystallization temperature of 50-80°C, and crystallization time of 0.5-4h.

[0019] Furthermore, the conventional hydrothermal crystallization conditions are: crystallization temperature 90-180° C., and crystallization time 4-36 h.

[0020] Furthermore, in the EMT / 13X mixed crystal molecular sieve, there is no other type of molecular sieve except EMT molecular sieve and 13X molecular sieve, and the EMT molecular sieve content in the mixed crystal molecular sieve is 60-90wt% and the specific surface area is ≥600m 2 / g, pore volume ≥ 0.35cm 3 / g, relative crystallinity ≥95%, the structure of the mixed crystal molecular sieve does not collapse when calcined at a high temperature of ≤900°C, and the thermal stability is good.

[0021] Furthermore, in step (1), the thickness of the obtained wet filter cake is ≤2 cm and the water content is 55-65 wt%.

[0022] Furthermore, in step (2), the drying conditions are: drying temperature is 40-80° C., drying time is 4-24 h, and the moisture content of the filter cake after drying is 35-45 wt %.

[0023] Furthermore, in step (2), the inorganic auxiliary agent is one or more of aluminum hydroxide, quick-de-powdering and pseudo-boehmite, and the amount of the inorganic auxiliary agent accounts for 15 to 40 wt% of the dry basis of the final calcined product.

[0024] Furthermore, the pore-forming agent is one or more of methyl cellulose, sesbania powder, maltodextrin, starch, carboxypropyl methyl cellulose and carboxyethyl cellulose, and the amount of the pore-forming agent accounts for 0.5-4wt% of the dry basis of the final calcined product.

[0025] Furthermore, in the granulation process, the rolling granulation method can be selected from sugar granulator granulation, disc granulation or drum granulation, preferably drum granulation, and the liquid binder used in the granulation process is water.

[0026] Furthermore, in step (3), the calcination process is carried out in a gas environment with an oxygen content of ≥40%, a calcination temperature of 350-550° C., and a calcination time of 1-10 h.

[0027] The second technical solution of the present invention provides a high-efficiency molecular sieve adsorbent for deep purification of oxygenated substances, which is prepared by any of the above-mentioned preparation methods. It has a larger specific surface area, smaller adsorption heat and lower abrasion, and its specific surface area is ≥450m 2 / g, ethylene adsorption heat ≤70℃, and abrasion ≤0.3wt%.

[0028] The third technical solution of the present invention provides an application of a high-efficiency molecular sieve adsorbent for deep purification of oxygenates, which is used for the efficient removal of non-polar or polar oxygenates in light olefins.

[0029] Specifically, the method for using the EMT / 13X mixed crystal molecular sieve adsorbent is to install the molecular sieve adsorbent in a fixed bed reactor, introduce a light olefin stream, and remove impurities from the reactor before flowing out from the other side. The carrier gas pressure is 1-2 MPa, the temperature is 30-40°C, the molar ratio of dimethyl ether, methanol and propionaldehyde is 1:1:1, and the feed gas space velocity is 0.3-3.5 h -1 The adsorbent performance was evaluated under the following conditions.

[0030] The EMT / 13X mixed crystal molecular sieve adsorbent has a higher oxygenate adsorption capacity and purification depth. Its oxygenate adsorption capacity increases by ≥30% and the purification depth can reach below 1ppb. It is suitable for the efficient removal of trace non-polar or polar oxygenates such as dimethyl ether, methanol, and propionaldehyde in light olefins, meeting the demand for higher purity olefins for high-end polyolefin catalysts.

[0031] Compared with the prior art, the present invention has the following advantages:

[0032] (1) The present invention synergistically combines the dual-template method with the two-step hydrothermal crystallization method of microwave hydrothermal crystallization followed by traditional hydrothermal crystallization, and solves the technical problem of preparing a structurally complete and highly crystallized EMT / 13X mixed crystal molecular sieve by the mixed template method for the first time. In the synthesis method provided by the present invention, the hydrothermal crystallization of the EMT molecular sieve is separated from the hydrothermal crystallization process of the 13X molecular sieve, and the EMT / 13X mixed crystal molecular sieve with the EMT molecular sieve as the main component can be achieved by simply regulating the dual-template composition and the crystallization temperature and crystallization time, thereby effectively reducing the synthesis cost of the EMT molecular sieve by reducing the amount of the crown ether template. In addition, the substantial shortening of the crystallization time greatly reduces the synthesis energy consumption of the mixed crystal molecular sieve and improves the synthesis yield of the mixed crystal molecular sieve.

[0033] (2) The present invention directly uses the EMT / 13X mixed crystal molecular sieve after filter pressing as raw material, and obtains the finished molecular sieve adsorbent after granulation and molding, which not only avoids the use of a large amount of water washing process of the original powder, but also reduces the process of high-temperature roasting to remove the template agent in the mixed crystal molecular sieve original powder. Its preparation process is shorter and energy consumption is lower. In addition, the preparation process of the EMT / 13X mixed crystal molecular sieve adsorbent does not require an additional curing process. The molecular sieve adsorbent can be given sufficient crushing strength by relying solely on the residual alkali in the wet filter cake, further shortening the preparation process and reducing energy consumption. The use of the dual template method and the two-step hydrothermal crystallization method of microwave hydrothermal crystallization followed by traditional hydrothermal crystallization and the mutual matching with the simplified molding process flow have greatly reduced the manufacturing cost of the molecular sieve adsorbent.

[0034] (3) The molecular sieve adsorbent prepared by the present invention is a dual-active component, which has a larger specific surface area, smaller adsorption heat and lower attrition. The low adsorption heat avoids the pre-loading process when the adsorbent is first used. In addition, the synergistic combination of 13X molecular sieve and EMT molecular sieve not only ensures the adsorption capacity and purification depth of the molecular sieve adsorbent for oxides, but also enables it to have the ability to deeply purify non-polar or weakly polar oxides. The adsorption capacity of the oxides of the prepared EMT / 13X mixed crystal molecular sieve adsorbent is increased by ≧30%, and the purification depth can reach below 1ppb, meeting the demand of high-end polyolefin catalysts for higher purity olefins. In addition, under the same filling volume, the regeneration cycle and service life of the EMT / 13X mixed crystal molecular sieve adsorbent prepared by the present invention are longer, and the regeneration switching frequency and operating costs are lower. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is the XRD spectrum of the EMT / 13X mixed crystal molecular sieve adsorbent prepared in Example 1;

[0036] Figure 2 This is the SEM spectrum of the EMT / 13X mixed crystal molecular sieve adsorbent prepared in Example 1;

[0037] Figure 3 is the XRD spectrum of the EMT / 13X mixed crystal molecular sieve adsorbent prepared in Example 2;

[0038] Figure 4 This is the XRD spectrum of the EMT / 13X mixed crystal molecular sieve adsorbent prepared in Example 3. DETAILED DESCRIPTION

[0039] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0040] In the following examples, unless otherwise specified, raw materials or processing techniques are conventional commercially available raw materials or conventional processing techniques in the art.

[0041] Example 1:

[0042] Synthesis of EMT / 13X mixed crystal molecular sieves: Sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 18-crown-6, and tetraethylammonium hydroxide were mixed uniformly at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6):n(tetraethylammonium hydroxide) = 1:10:5:300:0.6:0.4 to prepare the EMT molecular sieve. The method involved weighing a certain mass of flaky sodium hydroxide solid and dissolving it in deionized water. Sodium metaaluminate solid was then added under stirring to fully dissolve it. The solution was filtered to remove impurities and the silica sol and a certain ratio of 18-crown-6 and tetraethylammonium hydroxide templates were then slowly added. The mixture was aged at room temperature for 40 hours to obtain the synthesis solution. Finally, the obtained synthetic liquid is first subjected to microwave hydrothermal crystallization at 300W power and 60°C for 3 hours, then transferred to a hydrothermal reactor for hydrothermal crystallization at 150°C for 12 hours, and finally the crystallized mixed liquid is filtered to obtain a filter cake.

[0043] Granulation: The wet filter cake after filtration was dried at 60°C for 18 hours, and then the EMT / 13X mixed crystal molecular sieve filter cake, quick de-powdering, and 2wt% of the final calcined product starch were weighed according to a dry basis ratio of 80:20. After mixing evenly, water was used as a liquid binder and granulated using a drum. After drying at 100°C for 24 hours, the EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm was obtained by sieving.

[0044] Baking: the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product is placed in an atmosphere furnace, a gas with an oxygen content of 50% is introduced, and the temperature is increased to 550°C at a rate of 5°C / min, and baking is carried out for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0045] The content and structure analysis of the prepared EMT / 13X mixed crystal molecular sieve raw powder shows that the EMT molecular sieve content in the EMT / 13X mixed crystal molecular sieve raw powder is 60.18%, the 13X molecular sieve content is 39.82%, the specific surface area is 598.67m 2 / g, the pore volume is 0.34cm 2 / g, the relative crystallinity is 96.8%, the XRD spectrum is shown in Figure 1 , and the SEM image is shown in Figure 2 .

[0046] The EMT / 13X mixed crystal molecular sieve adsorbent after granulation is tested and analyzed, and the results are shown in Table 1.

[0047] Comparative Example 1

[0048] Granulation: pure phase EMT molecular sieve and pure phase 13X molecular sieve are weighed according to the EMT molecular sieve content (dry basis) of 60.18wt% and the 13X molecular sieve content (dry basis) of 39.82wt%, and then mixed uniformly; the EMT molecular sieve and the 13X molecular sieve mixed powder, the quick release powder, and the starch accounting for 2wt% of the total mass of the baked product are weighed according to the dry basis ratio of 80:20, mixed uniformly, and then granulated by using a drum with water as a liquid binder. After drying at 100°C for 24 hours, screening is carried out to obtain an EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0mm.

[0049] Baking: the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product is placed in an atmosphere furnace, a gas with an oxygen content of 50% is introduced, and the temperature is increased to 550°C at a rate of 5°C / min, and baking is carried out for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0050] The EMT / 13X mixed crystal molecular sieve adsorbent is tested and analyzed, and the results are shown in Table 1.

[0051] Example 2

[0052] Synthesis of EMT / 13X mixed crystal molecular sieves: Sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 18-crown-6, and tetraethylammonium hydroxide were mixed uniformly at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6):n(tetraethylammonium hydroxide) = 1:10:5:300:0.7:0.3. The EMT molecular sieve was prepared by mixing a certain amount of flaky sodium hydroxide solid in deionized water, adding sodium metaaluminate solid under stirring until fully dissolved, and filtering to remove impurities to obtain a sodium aluminate solution. Silica sol and a certain ratio of 18-crown-6 and tetraethylammonium hydroxide templates were then slowly added, and the mixture was aged at room temperature for 40 hours to obtain the synthesis solution. Finally, the obtained synthetic liquid is first subjected to microwave hydrothermal crystallization at 300W power and 60°C for 3 hours, then transferred to a hydrothermal reactor for hydrothermal crystallization at 150°C for 12 hours, and finally the crystallized mixed liquid is filtered to obtain a filter cake.

[0053] Granulation: The wet filter cake after filtration was dried at 60°C for 18 hours, and then the EMT / 13X mixed crystal molecular sieve filter cake, quick-de-powdering and starch accounting for 2 wt% of the total mass of the calcined product were weighed according to a dry basis ratio of 80:20. After mixing evenly, water was used as a liquid binder and granulated by a drum. After drying at 100°C for 24 hours, the EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm was obtained by sieving.

[0054] Calcination: Place the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0055] The content and structure analysis of the prepared EMT / 13X mixed crystal molecular sieve raw powder showed that the EMT molecular sieve content in the EMT / 13X mixed crystal molecular sieve raw powder was 73.45%, the 13X molecular sieve content was 26.55%, and the specific surface area was 591.1m 2 / g, pore volume of 0.36cm 2 / g, relative crystallinity is 100.3%, and its XRD spectrum is shown in Figure 3 .

[0056] The granulated EMT / 13X mixed crystal molecular sieve adsorbent was tested and analyzed, and the results are shown in Table 1.

[0057] Comparative Example 2

[0058] Granulation: EMT molecular sieve and 13X molecular sieve in pure phase were weighed according to the content of EMT molecular sieve (dry basis) of 73.45wt% and the content of 13X molecular sieve (dry basis) of 26.55wt%, and then mixed uniformly; EMT molecular sieve and 13X molecular sieve mixed powder, quick release powder and starch accounting for 2wt% of the total mass of the calcined product were weighed according to the dry basis ratio of 80:20, mixed uniformly, and then granulated by using a roller with water as a liquid binder. After drying at 100℃ for 24 hours, the EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0mm was obtained by screening.

[0059] Calcination: The dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product was placed in an atmosphere furnace, and a gas with an oxygen content of 50% was introduced. The temperature was raised to 550℃ at a rate of 5℃ / min, and calcination was carried out for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0060] The EMT / 13X mixed crystal molecular sieve adsorbent was tested and analyzed, and the results are shown in Table 1.

[0061] Example 3

[0062] EMT / 13X mixed crystal molecular sieve synthesis: Sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 18-crown-6 and tetraethylammonium hydroxide were mixed uniformly at room temperature according to the ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6):n(tetraethylammonium hydroxide) = 1:10:5:300:0.8:0.2 to prepare EMT molecular sieve. The specific method is as follows: a certain amount of flaky sodium hydroxide solid was dissolved in deionized water, and sodium metaaluminate solid was added under stirring conditions to make it fully dissolved, and the resulting sodium aluminate solution was filtered to remove impurities. Then, silica sol, 18-crown-6 and tetraethylammonium hydroxide template were slowly added, and the resulting synthesis liquid was aged at room temperature for 40 hours. Finally, the obtained synthesis liquid was subjected to microwave hydrothermal crystallization at 300w power and 60℃ for 3 hours, and then transferred to a hydrothermal reaction kettle for hydrothermal crystallization at 150℃ for 12h. Finally, the mixed liquid after crystallization was filtered to obtain a filter cake.

[0063] Granulation: The wet filter cake after filtration was dried at 60℃ for 18h, and then EMT / 13X mixed crystal molecular sieve filter cake, quick release powder and starch accounting for 2wt% of the total mass of the calcined product were weighed according to the dry basis ratio of 80:20, mixed uniformly, and then granulated by using a roller with water as a liquid binder. After drying at 100℃ for 24 hours, the EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0mm was obtained by screening.

[0064] Calcination: Place the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0065] The content and structure analysis of the prepared EMT / 13X mixed crystal molecular sieve raw powder showed that the EMT molecular sieve content in the EMT / 13X mixed crystal molecular sieve raw powder was 82.49%, the 13X molecular sieve content was 17.51%, and the specific surface area was 601.28m 2 / g, pore volume of 0.37cm 2 / g, relative crystallinity is 99.57%, and its XRD spectrum is shown in Figure 4 .

[0066] The granulated EMT / 13X mixed crystal molecular sieve adsorbent was tested and analyzed, and the results are shown in Table 1.

[0067] Comparative Example 3

[0068] Granulation: Pure EMT molecular sieve and pure 13X molecular sieve were weighed according to the EMT molecular sieve content (dry basis) of 82.49% and the 13X molecular sieve content (dry basis) of 17.51%, and then mixed evenly; EMT molecular sieve and 13X molecular sieve mixed powder, quick de-powdering and starch accounting for 2wt% of the total mass of the calcined product were weighed according to the dry basis ratio of 80:20. After mixing evenly, water was used as the liquid binder and granulated by a drum. After drying at 100°C for 24 hours, sieving can obtain an EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm.

[0069] Calcination: Place the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0070] The EMT / 13X mixed crystal molecular sieve adsorbent was tested and analyzed, and the results are shown in Table 1.

[0071] Comparative Example 4

[0072] To synthesize pure EMT molecular sieves, sodium metaaluminate, silica sol, sodium hydroxide, deionized water, and 18-crown-6 were mixed at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6) = 1:10:5:300:1. The method involved weighing a certain amount of flaky sodium hydroxide solid and dissolving it in deionized water. The sodium metaaluminate solid was then added under stirring to fully dissolve it. The solution was filtered to remove impurities and obtain a sodium aluminate solution. The silica sol and 18-crown-6 template were then slowly added, stirred at room temperature, and aged for 24 hours to obtain a synthetic solution. Finally, the resulting solution was transferred to a hydrothermal reactor for hydrothermal crystallization at 110°C for 15 days. The solution was then filtered, washed to a pH of 7-8, dried at 100°C, and calcined at 550°C for 6 hours to obtain the pure EMT molecular sieve.

[0073] Granulation: EMT molecular sieve powder, quick-drying powder and starch accounting for 2wt% of the total mass of the roasted product are weighed according to a dry basis ratio of 80:20. After mixing evenly, water is used as a liquid binder and granulated by a roller. After drying at 100°C for 24 hours, the pure phase EMT molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm is obtained by sieving.

[0074] Calcination: Place the dried pure phase EMT molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the pure phase EMT molecular sieve adsorbent.

[0075] The structural analysis of the prepared pure phase EMT molecular sieve raw powder showed that the specific surface area of ​​the pure phase EMT molecular sieve raw powder was 599.6m 2 / g, pore volume of 0.36cm 2 / g, and the relative crystallinity is 99.21%.

[0076] The pure phase EMT molecular sieve adsorbent after granulation was tested and analyzed, and the results are shown in Table 1.

[0077] Comparative Example 5

[0078] Granulation: Weigh 13X molecular sieve powder, quick-de-powder and 2 wt% of the total mass of the roasted product from Luoyang Jianlong at a dry basis ratio of 80:20. Mix well and use water as a liquid binder for granulation using a roller. Dry at 100°C for 24 hours and then sieve to obtain a pure phase 13X molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm.

[0079] Calcination: Place the dried pure phase 13X molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and raise the temperature to 550°C at 5°C / min for 4 hours to obtain the pure phase 13X molecular sieve adsorbent.

[0080] The structural analysis of the pure phase 13X molecular sieve raw powder shows that the specific surface area of ​​the pure phase EMT molecular sieve raw powder is 605.8m 2 / g, pore volume of 0.32cm 2 / g, and the relative crystallinity is 98.35%.

[0081] The pure phase 13X molecular sieve adsorbent was tested and analyzed, and the results are shown in Table 1.

[0082] Example 4:

[0083] Synthesis of EMT / 13X mixed crystal molecular sieve: Sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 18-crown-6, and tetraethylammonium hydroxide were mixed uniformly at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6):n(tetraethylammonium hydroxide) = 1:10:5:300:0.6:0.4 to prepare the EMT molecular sieve. The method involved weighing a certain amount of flaky sodium hydroxide solid and dissolving it in deionized water. Sodium metaaluminate solid was then added under stirring to fully dissolve it. The solution was filtered to remove impurities and the silica sol and a certain ratio of 18-crown-6 and tetraethylammonium hydroxide template were then slowly added. The mixture was aged at room temperature for 36 hours to obtain the synthesis solution. Finally, the obtained synthetic liquid was first subjected to microwave hydrothermal crystallization at 400W power and 60°C for 2 hours, then transferred to a hydrothermal reactor for hydrothermal crystallization at 90°C for 36 hours, and finally the crystallized mixed liquid was filtered to obtain a filter cake.

[0084] Granulation: The wet filter cake after filtration was dried at 60°C for 18 hours, and then the EMT / 13X mixed crystal molecular sieve filter cake, quick-drying powder, and starch accounting for 2 wt% of the total mass of the calcined product were weighed according to a dry basis ratio of 80:20. After mixing evenly, water was used as a liquid binder and granulated by a drum. After drying at 100°C for 24 hours, the EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm was obtained by sieving.

[0085] Calcination: Place the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0086] The content and structure analysis of the prepared EMT / 13X mixed crystal molecular sieve raw powder showed that the EMT molecular sieve content in the EMT / 13X mixed crystal molecular sieve raw powder was 59.23%, the 13X molecular sieve content was 40.77%, and the specific surface area was 595.15m 2 / g, pore volume of 0.33cm 2 / g, relative crystallinity is 95.1%

[0087] The EMT / 13X mixed crystal molecular sieve adsorbent was tested and analyzed, and the results are shown in Table 3.

[0088] Example 5:

[0089] Synthesis of EMT / 13X mixed crystal molecular sieves: Sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 18-crown-6, and tetraethylammonium hydroxide were mixed uniformly at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6):n(tetraethylammonium hydroxide) = 1:10:5:300:0.6:0.4 to prepare the EMT molecular sieve. The method involved weighing a certain mass of flaky sodium hydroxide solid and dissolving it in deionized water. Sodium metaaluminate solid was then added under stirring to fully dissolve it. The solution was filtered to remove impurities and the silica sol and a certain ratio of 18-crown-6 and tetraethylammonium hydroxide template were then slowly added. The mixture was aged at room temperature for 96 hours to obtain the synthesis solution. Finally, the obtained synthetic liquid was first subjected to microwave hydrothermal crystallization at 600W power and 80°C for 0.5 hour, then transferred to a hydrothermal reactor for hydrothermal crystallization at 180°C for 4 hours, and finally the crystallized mixed liquid was filtered to obtain a filter cake.

[0090] Granulation: The wet filter cake after filtration was dried at 60°C for 18 hours, and then the EMT / 13X mixed crystal molecular sieve filter cake, quick-drying powder, and starch accounting for 2 wt% of the total mass of the calcined product were weighed according to a dry basis ratio of 80:20. After mixing evenly, water was used as a liquid binder and granulated by a drum. After drying at 100°C for 24 hours, the EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm was obtained by sieving.

[0091] Calcination: Place the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0092] The content and structure analysis of the prepared EMT / 13X mixed crystal molecular sieve raw powder showed that the EMT molecular sieve content in the EMT / 13X mixed crystal molecular sieve raw powder was 63.53%, the 13X molecular sieve content was 36.47%, and the specific surface area was 592.17 m 2 / g, pore volume of 0.34cm 2 / g, and the relative crystallinity is 93.7%.

[0093] The EMT / 13X mixed crystal molecular sieve adsorbent was tested and analyzed, and the results are shown in Table 3.

[0094] Example 6:

[0095] Synthesis of EMT / 13X mixed crystal molecular sieve: Sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 18-crown-6, and tetraethylammonium hydroxide were mixed uniformly at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6):n(tetraethylammonium hydroxide) = 1:10:5:300:0.6:0.4 to prepare the EMT molecular sieve. The method involved weighing a certain amount of flaky sodium hydroxide solid and dissolving it in deionized water. Sodium metaaluminate solid was then added under stirring to fully dissolve it. The solution was filtered to remove impurities and the silica sol and a certain ratio of 18-crown-6 and tetraethylammonium hydroxide template were then slowly added. The mixture was aged at room temperature for 48 hours to obtain the synthesis solution. Finally, the obtained synthetic liquid was first subjected to microwave hydrothermal crystallization at 300W power and 50°C for 4 hours, then transferred to a hydrothermal reactor for hydrothermal crystallization at 120°C for 18 hours, and finally the crystallized mixed liquid was filtered to obtain a filter cake.

[0096] Granulation: The wet filter cake after filtration was dried at 60°C for 18 hours, and then the EMT / 13X mixed crystal molecular sieve filter cake, quick-drying powder, and starch accounting for 2 wt% of the total mass of the calcined product were weighed according to a dry basis ratio of 80:20. After mixing evenly, water was used as a liquid binder and granulated by a drum. After drying at 100°C for 24 hours, the EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm was obtained by sieving.

[0097] Calcination: Place the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0098] The content and structure analysis of the prepared EMT / 13X mixed crystal molecular sieve raw powder showed that the EMT molecular sieve content in the EMT / 13X mixed crystal molecular sieve raw powder was 62.74%, the 13X molecular sieve content was 37.26%, and the specific surface area was 593.13 m 2 / g, pore volume of 0.34cm 2 / g, and the relative crystallinity is 95.2%.

[0099] The EMT / 13X mixed crystal molecular sieve adsorbent was tested and analyzed, and the results are shown in Table 3.

[0100] Example 7:

[0101] Synthesis of EMT / 13X mixed crystal molecular sieves: Sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 15-crown-5, and tetraethylammonium hydroxide were mixed uniformly at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6):n(tetraethylammonium hydroxide) = 1:10:5:300:0.6:0.4 to prepare the EMT molecular sieve. The method involved weighing a certain amount of flaky sodium hydroxide solid and dissolving it in deionized water. Sodium metaaluminate solid was then added under stirring to fully dissolve it. The solution was filtered to remove impurities and the silica sol was then slowly added with a certain ratio of 15-crown-5 and tetraethylammonium hydroxide as templates. The mixture was aged at room temperature for 40 hours to obtain the synthesis solution. Finally, the obtained synthetic liquid is first subjected to microwave hydrothermal crystallization at 300W power and 60°C for 3 hours, then transferred to a hydrothermal reactor for hydrothermal crystallization at 150°C for 12 hours, and finally the crystallized mixed liquid is filtered to obtain a filter cake.

[0102] Granulation: The wet filter cake after filtration was dried at 60°C for 18 hours, and then the EMT / 13X mixed crystal molecular sieve filter cake, quick-drying powder, and starch accounting for 2 wt% of the total mass of the calcined product were weighed according to a dry basis ratio of 80:20. After mixing evenly, water was used as a liquid binder and granulated by a drum. After drying at 100°C for 24 hours, the EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm was obtained by sieving.

[0103] Calcination: Place the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0104] The content and structure analysis of the prepared EMT / 13X mixed crystal molecular sieve raw powder showed that the EMT molecular sieve content in the EMT / 13X mixed crystal molecular sieve raw powder was 57.29%, the 13X molecular sieve content was 42.71%, and the specific surface area was 596.17 m 2 / g, pore volume of 0.35cm 2 / g, and the relative crystallinity is 94.5%.

[0105] The EMT / 13X mixed crystal molecular sieve adsorbent was tested and analyzed, and the results are shown in Table 3.

[0106] Example 8:

[0107] Synthesis of EMT / 13X mixed crystal molecular sieve: Sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 18-crown-6, and triethylamine were mixed at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6):n(triethylamine) = 1:10:5:300:0.6:0.4 to prepare the EMT molecular sieve. The method involved weighing a certain mass of flaky sodium hydroxide solid and dissolving it in deionized water. Sodium metaaluminate solid was then added under stirring to fully dissolve it. The solution was filtered to remove impurities and the silica sol and a certain ratio of 18-crown-6 and triethylamine template were then slowly added. The mixture was aged at room temperature for 40 hours to obtain the synthesis solution. Finally, the obtained synthetic liquid is first subjected to microwave hydrothermal crystallization at 300W power and 60°C for 3 hours, then transferred to a hydrothermal reactor for hydrothermal crystallization at 150°C for 12 hours, and finally the crystallized mixed liquid is filtered to obtain a filter cake.

[0108] Granulation: The wet filter cake after filtration was dried at 60°C for 18 hours, and then the EMT / 13X mixed crystal molecular sieve filter cake, quick-drying powder, and starch accounting for 2 wt% of the total mass of the calcined product were weighed according to a dry basis ratio of 80:20. After mixing evenly, water was used as a liquid binder and granulated by a drum. After drying at 100°C for 24 hours, the EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm was obtained by sieving.

[0109] Calcination: Place the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0110] The content and structure analysis of the prepared EMT / 13X mixed crystal molecular sieve raw powder showed that the EMT molecular sieve content in the EMT / 13X mixed crystal molecular sieve raw powder was 62.69%, the 13X molecular sieve content was 37.31%, and the specific surface area was 596.31m 2 / g, pore volume of 0.35cm 2 / g, and the relative crystallinity is 97.2%.

[0111] The EMT / 13X mixed crystal molecular sieve adsorbent was tested and analyzed, and the results are shown in Table 3.

[0112] Example 9:

[0113] Synthesis of EMT / 13X mixed crystal molecular sieve: sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 18-crown-6 ether and n-butylamine are mixed uniformly at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6 ether):n(n-butylamine) = 1:10:5:300:0.6:0.4. The specific method is as follows: a certain amount of flaky sodium hydroxide solid is dissolved in deionized water, and sodium metaaluminate solid is added under stirring conditions to make it fully dissolved, and a sodium aluminate solution is obtained after filtration. Then, silica sol, 18-crown-6 ether and n-butylamine template agent are slowly added, and the synthesis liquid is obtained after aging at room temperature for 40 hours. Finally, the obtained synthesis liquid is first subjected to microwave hydrothermal crystallization at 300w power and 60°C for 3 hours, and then transferred to a hydrothermal reaction kettle for hydrothermal crystallization at 150°C for 12 hours, and finally the crystallized mixed liquid is filtered to obtain a filter cake.

[0114] Granulation: the wet filter cake after filtration is dried at 60°C for 18h, and then EMT / 13X mixed crystal molecular sieve filter cake, quick-release powder, and 2wt% of starch based on the total mass of the calcined product are weighed according to the dry basis ratio of 80:20, mixed uniformly, and granulated with water as the liquid binder using a drum. After drying at 100°C for 24 hours, the EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0mm is obtained after screening.

[0115] Calcination: the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product is placed in a gas atmosphere furnace, and a gas with an oxygen content of 50% is introduced, and the temperature is raised to 550°C at a rate of 5°C / min and calcined for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0116] The content and structure analysis of the prepared EMT / 13X mixed crystal molecular sieve raw powder shows that the EMT molecular sieve content in the EMT / 13X mixed crystal molecular sieve raw powder is 58.41%, the 13X molecular sieve content is 41.59%, the specific surface area is 596.78m 2 / g, the pore volume is 0.34cm 2 / g, and the relative crystallinity is 96.14%.

[0117] The EMT / 13X mixed crystal molecular sieve adsorbent is tested and analyzed, and the results are shown in Table 3.

[0118] Example 10:

[0119] Synthesis of EMT / 13X mixed crystal molecular sieve: Sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 18-crown-6, and tetramethylammonium hydroxide were mixed uniformly at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6):n(tetramethylammonium hydroxide) = 1:10:5:300:0.6:0.4 to prepare the EMT molecular sieve. The method involved weighing a certain amount of flaky sodium hydroxide solid and dissolving it in deionized water. Sodium metaaluminate solid was then added under stirring to fully dissolve it. The solution was filtered to remove impurities and the silica sol and a certain ratio of 18-crown-6 and tetramethylammonium hydroxide template were then slowly added. The mixture was aged at room temperature for 40 hours to obtain the synthesis solution. Finally, the obtained synthetic liquid is first subjected to microwave hydrothermal crystallization at 300W power and 60°C for 3 hours, then transferred to a hydrothermal reactor for hydrothermal crystallization at 150°C for 12 hours, and finally the crystallized mixed liquid is filtered to obtain a filter cake.

[0120] Granulation: The wet filter cake after filtration was dried at 60°C for 18 hours, and then the EMT / 13X mixed crystal molecular sieve filter cake, quick-drying powder, and starch accounting for 2 wt% of the total mass of the calcined product were weighed according to a dry basis ratio of 80:20. After mixing evenly, water was used as a liquid binder and granulated by a drum. After drying at 100°C for 24 hours, the EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm was obtained by sieving.

[0121] Calcination: Place the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0122] The content and structure analysis of the prepared EMT / 13X mixed crystal molecular sieve raw powder showed that the EMT molecular sieve content in the EMT / 13X mixed crystal molecular sieve raw powder was 55.29%, the 13X molecular sieve content was 44.71%, and the specific surface area was 596.13 m 2 / g, pore volume of 0.35cm 2 / g, and the relative crystallinity is 96.68%.

[0123] The EMT / 13X mixed crystal molecular sieve adsorbent was tested and analyzed, and the results are shown in Table 3.

[0124] Example 11:

[0125] Synthesis of EMT / 13X mixed crystal molecular sieves: Sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 18-crown-6, and tetraethylammonium hydroxide were mixed uniformly at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6):n(tetraethylammonium hydroxide) = 1:10:5:300:0.6:0.4 to prepare the EMT molecular sieve. The method involved weighing a certain mass of flaky sodium hydroxide solid and dissolving it in deionized water. Sodium metaaluminate solid was then added under stirring to fully dissolve it. The solution was filtered to remove impurities and the silica sol and a certain ratio of 18-crown-6 and tetraethylammonium hydroxide templates were then slowly added. The mixture was aged at room temperature for 40 hours to obtain the synthesis solution. Finally, the obtained synthetic liquid is first subjected to microwave hydrothermal crystallization at 300W power and 60°C for 3 hours, then transferred to a hydrothermal reactor for hydrothermal crystallization at 150°C for 12 hours, and finally the crystallized mixed liquid is filtered to obtain a filter cake.

[0126] Granulation: The wet filter cake after filtration was dried at 60°C for 18 hours, and then the EMT / 13X mixed crystal molecular sieve filter cake, quick-drying powder, and starch accounting for 2 wt% of the total mass of the calcined product were weighed according to a dry basis ratio of 80:20. After mixing evenly, water was used as a liquid binder and granulated by a drum. After drying at 100°C for 24 hours, the EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm was obtained by sieving.

[0127] Calcination: Place the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0128] The content and structure analysis of the prepared EMT / 13X mixed crystal molecular sieve raw powder showed that the EMT molecular sieve content in the EMT / 13X mixed crystal molecular sieve raw powder was 61.83%, the 13X molecular sieve content was 38.17%, and the specific surface area was 595.91m 2 / g, pore volume of 0.34cm 2 / g, and the relative crystallinity is 97.14%.

[0129] The EMT / 13X mixed crystal molecular sieve adsorbent was tested and analyzed, and the results are shown in Table 3.

[0130] Example 12:

[0131] Synthesis of EMT / 13X mixed crystal molecular sieves: Sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 18-crown-6, and polyethylene glycol were mixed uniformly at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6):n(polyethylene glycol) = 1:10:5:300:0.6:0.4. The EMT molecular sieve was prepared by mixing a certain amount of flaky sodium hydroxide solid in deionized water, adding sodium metaaluminate solid under stirring until fully dissolved, and filtering to remove impurities to obtain a sodium aluminate solution. Silica sol and a certain ratio of 18-crown-6 and polyethylene glycol template were then slowly added, and the mixture was aged at room temperature for 40 hours to obtain the synthesis solution. Finally, the obtained synthetic liquid is first subjected to microwave hydrothermal crystallization at 300W power and 60°C for 3 hours, then transferred to a hydrothermal reactor for hydrothermal crystallization at 150°C for 12 hours, and finally the crystallized mixed liquid is filtered to obtain a filter cake.

[0132] Granulation: The wet filter cake after filtration was dried at 60°C for 18 hours, and then the EMT / 13X mixed crystal molecular sieve filter cake, quick-drying powder, and starch accounting for 2 wt% of the total mass of the calcined product were weighed according to a dry basis ratio of 80:20. After mixing evenly, water was used as a liquid binder and granulated by a drum. After drying at 100°C for 24 hours, the EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm was obtained by sieving.

[0133] Calcination: Place the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0134] The content and structure analysis of the prepared EMT / 13X mixed crystal molecular sieve raw powder showed that the EMT molecular sieve content in the EMT / 13X mixed crystal molecular sieve raw powder was 59.14%, the 13X molecular sieve content was 40.86%, and the specific surface area was 591.99 m 2 / g, pore volume of 0.34cm 2 / g, and the relative crystallinity is 95.21%.

[0135] The EMT / 13X mixed crystal molecular sieve adsorbent was tested and analyzed, and the results are shown in Table 3.

[0136] Example 13:

[0137] Synthesis of EMT / 13X mixed crystal molecular sieves: Sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 18-crown-6, and polyquaternium-6 were mixed at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6):n(polyquaternium-6) = 1:10:5:300:0.6:0.4 to prepare the EMT molecular sieve. The method was as follows: a certain amount of flaky sodium hydroxide solid was weighed and dissolved in deionized water. Sodium metaaluminate solid was added under stirring to fully dissolve it, and then filtered to remove impurities to obtain a sodium aluminate solution. Silica sol and a certain ratio of 18-crown-6 and polyquaternium-6 templates were then slowly added. The mixture was aged at room temperature for 40 hours to obtain the synthesis solution. Finally, the obtained synthetic liquid is first subjected to microwave hydrothermal crystallization at 300W power and 60°C for 3 hours, then transferred to a hydrothermal reactor for hydrothermal crystallization at 150°C for 12 hours, and finally the crystallized mixed liquid is filtered to obtain a filter cake.

[0138] Granulation: The wet filter cake after filtration was dried at 60°C for 18 hours, and then the EMT / 13X mixed crystal molecular sieve filter cake, quick-drying powder, and starch accounting for 2 wt% of the total mass of the calcined product were weighed according to a dry basis ratio of 80:20. After mixing evenly, water was used as a liquid binder and granulated by a drum. After drying at 100°C for 24 hours, the EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm was obtained by sieving.

[0139] Calcination: Place the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0140] The content and structure analysis of the prepared EMT / 13X mixed crystal molecular sieve raw powder showed that the EMT molecular sieve content in the EMT / 13X mixed crystal molecular sieve raw powder was 61.42%, and the 13X molecular sieve content was 38.58%. Its specific surface area was 592.92 m 2 / g, pore volume of 0.35cm 2 / g, and the relative crystallinity is 95.1%.

[0141] The EMT / 13X mixed crystal molecular sieve adsorbent was tested and analyzed, and the results are shown in Table 3.

[0142] Example 14:

[0143] EMT / 13X mixed crystal molecular sieve synthesis: aluminum hydroxide, silica sol, sodium hydroxide, deionized water, 18-crown-6 and tetraethylammonium hydroxide are mixed in a ratio of n(Al2O3): n(SiO2): n(Na2O): n(H2O): n(18-crown-6): n(tetraethylammonium hydroxide) = 1:10:5:300:0.6:0.4 at room temperature to prepare EMT molecular sieve, the specific method is: a certain mass of flaky sodium hydroxide solid is dissolved in deionized water, and aluminum hydroxide solid is added under stirring conditions to make it fully dissolved, and the impurities are removed by filtration to obtain an aluminum hydroxide solution. Then slowly add silica sol with a certain proportion of 18-crown-6 and tetraethylammonium hydroxide template, and age at room temperature for 40 hours to obtain a synthesis solution. Finally, the obtained synthesis solution is first subjected to microwave hydrothermal crystallization at 300w power and 60°C for 3 hours, and then transferred to a hydrothermal reaction kettle for hydrothermal crystallization at 150°C for 12h, and finally the crystallized mixed solution is filtered to obtain a filter cake.

[0144] Granulation: The wet filter cake after filtration is dried at 60°C for 18h, and then EMT / 13X mixed crystal molecular sieve filter cake, quick-release powder, and 2wt% of starch based on the total mass of the roasted product are weighed according to the dry basis ratio of 80:20, mixed uniformly, and granulated with water as the liquid binder using a drum. After drying at 100°C for 24 hours, sieving can obtain EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0mm.

[0145] Roasting: The dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product is placed in an atmosphere furnace, and a gas with an oxygen content of 50% is introduced, and the temperature is raised to 550°C at a rate of 5°C / min and roasted for 4 hours to obtain an EMT / 13X composite molecular sieve adsorbent.

[0146] The content and structure analysis of the prepared EMT / 13X mixed crystal molecular sieve raw powder shows that the EMT molecular sieve content in the EMT / 13X mixed crystal molecular sieve raw powder is 61.22%, the 13X molecular sieve content is 38.78%, the specific surface area is 590.13m 2 / g, the pore volume is 0.33cm 2 / g, and the relative crystallinity is 94.1%.

[0147] The EMT / 13X mixed crystal molecular sieve adsorbent is tested and analyzed, and the results are shown in Table 3.

[0148] Example 15:

[0149] Synthesis of EMT / 13X mixed crystal molecular sieves: Sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 18-crown-6, and tetraethylammonium hydroxide were mixed uniformly at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6):n(tetraethylammonium hydroxide) = 1:10:5:300:0.6:0.4 to prepare the EMT molecular sieve. The method involved weighing a certain mass of flaky sodium hydroxide solid and dissolving it in deionized water. Sodium metaaluminate solid was then added under stirring to fully dissolve it. The solution was filtered to remove impurities and the silica sol and a certain ratio of 18-crown-6 and tetraethylammonium hydroxide templates were then slowly added. The mixture was aged at room temperature for 40 hours to obtain the synthesis solution. Finally, the obtained synthetic liquid is first subjected to microwave hydrothermal crystallization at 300W power and 60°C for 3 hours, then transferred to a hydrothermal reactor for hydrothermal crystallization at 150°C for 12 hours, and finally the crystallized mixed liquid is filtered to obtain a filter cake.

[0150] Granulation: The wet filter cake after filtration was dried at 60°C for 18 hours, and then the EMT / 13X mixed crystal molecular sieve filter cake, quick-drying powder, and methyl cellulose accounting for 2wt% of the total mass of the calcined product were weighed according to a dry basis ratio of 80:20. After mixing evenly, water was used as a liquid binder and granulated using a drum. After drying at 100°C for 24 hours, sieve to obtain an EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm.

[0151] Calcination: Place the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0152] Example 16:

[0153] Synthesis of EMT / 13X mixed crystal molecular sieves: Sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 18-crown-6, and tetraethylammonium hydroxide were mixed uniformly at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6):n(tetraethylammonium hydroxide) = 1:10:5:300:0.6:0.4 to prepare the EMT molecular sieve. The method involved weighing a certain mass of flaky sodium hydroxide solid and dissolving it in deionized water. Sodium metaaluminate solid was then added under stirring to fully dissolve it. The solution was filtered to remove impurities and the silica sol and a certain ratio of 18-crown-6 and tetraethylammonium hydroxide templates were then slowly added. The mixture was aged at room temperature for 40 hours to obtain the synthesis solution. Finally, the obtained synthetic liquid is first subjected to microwave hydrothermal crystallization at 300W power and 60°C for 3 hours, then transferred to a hydrothermal reactor for hydrothermal crystallization at 150°C for 12 hours, and finally the crystallized mixed liquid is filtered to obtain a filter cake.

[0154] Granulation: The wet filter cake after filtration was dried at 60°C for 18 hours, and then the EMT / 13X mixed crystal molecular sieve filter cake, aluminum hydroxide, and starch accounting for 2 wt% of the total mass of the calcined product were weighed according to a dry basis ratio of 80:20. After mixing evenly, water was used as a liquid binder and granulated by a drum. After drying at 100°C for 24 hours, sieve to obtain an EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm.

[0155] Calcination: Place the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0156] Example 17:

[0157] Synthesis of EMT / 13X mixed crystal molecular sieves: Sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 18-crown-6, and tetraethylammonium hydroxide were mixed uniformly at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6):n(tetraethylammonium hydroxide) = 1:10:5:300:0.6:0.4 to prepare the EMT molecular sieve. The method involved weighing a certain mass of flaky sodium hydroxide solid and dissolving it in deionized water. Sodium metaaluminate solid was then added under stirring to fully dissolve it. The solution was filtered to remove impurities and the silica sol and a certain ratio of 18-crown-6 and tetraethylammonium hydroxide templates were then slowly added. The mixture was aged at room temperature for 40 hours to obtain the synthesis solution. Finally, the obtained synthetic liquid is first subjected to microwave hydrothermal crystallization at 300W power and 60°C for 3 hours, then transferred to a hydrothermal reactor for hydrothermal crystallization at 150°C for 12 hours, and finally the crystallized mixed liquid is filtered to obtain a filter cake.

[0158] Granulation: The wet cake after filtration was dried at 60°C for 18 hours, and then the EMT / 13X mixed crystal molecular sieve filter cake, pseudo-boehmite, and starch accounting for 2 wt% of the total mass of the calcined product were weighed according to a dry basis ratio of 80:20. After mixing evenly, water was used as a liquid binder and granulated by a drum. After drying at 100°C for 24 hours, the EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm was obtained by sieving.

[0159] Calcination: Place the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0160] Comparative Example 6

[0161] Synthesis of EMT / 13X mixed crystal molecular sieve: Sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 18-crown-6, and tetraethylammonium hydroxide were mixed uniformly at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6):n(tetraethylammonium hydroxide) = 1:10:5:300:0.8:0.2 to prepare the EMT molecular sieve. The method was as follows: a certain amount of flaky sodium hydroxide solid was weighed and dissolved in deionized water. Sodium metaaluminate solid was added under stirring to fully dissolve it, and then filtered to remove impurities to obtain a sodium aluminate solution. Silica sol and a certain ratio of 18-crown-6 and tetraethylammonium hydroxide templates were then slowly added. The mixture was aged at room temperature for 40 hours to obtain the synthesis solution. Finally, the mixture was transferred to a hydrothermal reactor for hydrothermal crystallization at 150°C for 12 hours, and then the obtained synthetic liquid was subjected to microwave hydrothermal crystallization at 300W power and 60°C for 3 hours. Finally, the crystallized mixed liquid was filtered to obtain a filter cake.

[0162] Granulation: The wet filter cake after filtration was dried at 60°C for 18 hours, and then the EMT / 13X mixed crystal molecular sieve filter cake, quick-de-powdering and starch accounting for 2 wt% of the total mass of the calcined product were weighed according to a dry basis ratio of 80:20. After mixing evenly, water was used as a liquid binder and granulated by a drum. After drying at 100°C for 24 hours, the EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm was obtained by sieving.

[0163] Calcination: Place the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0164] The content and structure analysis of the prepared EMT / 13X mixed crystal molecular sieve raw powder showed that the EMT molecular sieve content in the EMT / 13X mixed crystal molecular sieve raw powder was 80.16%, and the 13X molecular sieve content was 19.84%. Its specific surface area was 500.24 m 2 / g, pore volume of 0.28cm 2 / g, and the relative crystallinity is 81.4%.

[0165] The EMT / 13X mixed crystal molecular sieve adsorbent was tested and analyzed, and the results are shown in Table 3.

[0166] Comparative Example 7

[0167] Synthesis of EMT / 13X mixed crystal molecular sieve: Sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 18-crown-6, and tetraethylammonium hydroxide were mixed uniformly at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6):n(tetraethylammonium hydroxide) = 1:10:5:300:0.8:0.2 to prepare the EMT molecular sieve. The method involves weighing a certain amount of flaky sodium hydroxide solid and dissolving it in deionized water. Sodium metaaluminate solid was then added under stirring to fully dissolve it. The solution was filtered to remove impurities and obtain a sodium aluminate solution. Silica sol and a certain ratio of 18-crown-6 and tetraethylammonium hydroxide templates were then slowly added. The mixture was aged at room temperature for 40 hours to obtain a synthetic solution. Finally, the resulting synthetic solution was transferred to a hydrothermal reactor for hydrothermal crystallization at 150°C for 15 hours. The crystallized mixture was then filtered to obtain a filter cake.

[0168] Granulation: The wet filter cake after filtration was dried at 60°C for 18 hours, and then the EMT / 13X mixed crystal molecular sieve filter cake, quick-de-powdering and starch accounting for 2 wt% of the total mass of the calcined product were weighed according to a dry basis ratio of 80:20. After mixing evenly, water was used as a liquid binder and granulated by a drum. After drying at 100°C for 24 hours, the EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm was obtained by sieving.

[0169] Calcination: Place the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0170] The content and structure analysis of the prepared EMT / 13X mixed crystal molecular sieve raw powder showed that the EMT molecular sieve content in the EMT / 13X mixed crystal molecular sieve raw powder was 81.64%, the 13X molecular sieve content was 18.36%, and the specific surface area was 491.62 m 2 / g, pore volume of 0.27cm 2 / g, and the relative crystallinity is 75.6%.

[0171] The EMT / 13X mixed crystal molecular sieve adsorbent was tested and analyzed, and the results are shown in Table 3.

[0172] Comparative Example 8

[0173] Synthesis of EMT / 13X mixed crystal molecular sieve: Sodium metaaluminate, silica sol, sodium hydroxide, deionized water, 18-crown-6, and tetraethylammonium hydroxide were mixed uniformly at room temperature in a ratio of n(Al2O3):n(SiO2):n(Na2O):n(H2O):n(18-crown-6):n(tetraethylammonium hydroxide) = 1:10:5:300:0.8:0.2 to prepare the EMT molecular sieve. The method involved weighing a certain amount of flaky sodium hydroxide solid and dissolving it in deionized water. Sodium metaaluminate solid was then added under stirring to fully dissolve it. The solution was filtered to remove impurities and obtain a sodium aluminate solution. Silica sol and a certain ratio of 18-crown-6 and tetraethylammonium hydroxide templates were then slowly added. The mixture was aged at room temperature for 40 hours to obtain a synthetic solution. Finally, the resulting synthetic solution was hydrothermally crystallized at 300 W power and 60°C for 15 hours. The crystallized mixture was then filtered to obtain a filter cake.

[0174] Granulation: The wet filter cake after filtration was dried at 60°C for 18 hours, and then the EMT / 13X mixed crystal molecular sieve filter cake, quick-de-powdering and starch accounting for 2 wt% of the total mass of the calcined product were weighed according to a dry basis ratio of 80:20. After mixing evenly, water was used as a liquid binder and granulated by a drum. After drying at 100°C for 24 hours, the EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product with a particle size of 3.0-4.0 mm was obtained by sieving.

[0175] Calcination: Place the dried EMT / 13X mixed crystal molecular sieve adsorbent semi-finished product in an atmosphere furnace, introduce a gas with an oxygen content of 50%, and calcine at 5°C / min to 550°C for 4 hours to obtain the EMT / 13X composite molecular sieve adsorbent.

[0176] The content and structure analysis of the prepared EMT / 13X mixed crystal molecular sieve raw powder showed that the EMT molecular sieve content in the EMT / 13X mixed crystal molecular sieve raw powder was 81.17%, and the 13X molecular sieve content was 18.83%. Its specific surface area was 411.35 m 2 / g, pore volume of 0.29cm 2 / g, and the relative crystallinity is 84.32%.

[0177] The EMT / 13X mixed crystal molecular sieve adsorbent was tested and analyzed, and the results are shown in Table 3.

[0178] Example 18

[0179] The prepared molecular sieve balls (1.5 g) with different composition contents were installed in a fixed bed reactor. The olefin stream flowed through the reactor and, after impurities were removed, flowed into a gas phase detector (GC2060, chromatographic column KB-5, 30 m) from the other side of the reactor. The carrier gas pressure was 1.2 MPa, the temperature was 35°C, the molar ratio of methanol, propionaldehyde and dimethyl ether was 1:1:1, and the feed gas space velocity was 2.5 h -1 Under the conditions of 100 ppm, the removal of oxygenate impurities from an olefin stream was evaluated, with a breakthrough concentration of 1 ppb. The resulting data are shown in Tables 1 and 2 below.

[0180] Table 1 General performance data of the adsorbents prepared in Examples 1-3 and Comparative Examples 1-5

[0181]

[0182] Table 2 Evaluation data of oxygenate purification performance of adsorbents prepared in Examples 1-3 and Comparative Examples 1-5

[0183]

[0184]

[0185] Table 3 General performance data of the adsorbents prepared in Examples 4-14 and Comparative Examples 6-8

[0186]

[0187] As shown in Tables 1 and 2, the prepared EMT / 13X mixed crystal molecular sieve adsorbent exhibits good deep purification performance for dimethyl ether, methanol and propionaldehyde. As the content of 13X molecular sieve in the EMT / 13X mixed crystal molecular sieve adsorbent increases, the adsorption capacity of the EMT / 13X mixed crystal molecular sieve adsorbent for dimethyl ether increases. Compared with Comparative Examples 1-3, the adsorbent prepared using the EMT / 13X mixed crystal molecular sieve obtained by direct crystallization as a raw material has a larger oxide adsorption capacity, higher crushing strength and lower ethylene adsorption heat, which may be attributed to the residual sodium hydroxide acting as a binder to increase the strength of the granulated product. At the same time, the residual sodium hydroxide in the pores not only reduces the molecular sieve pores, but also weakens the surface properties of the pores and reduces the electrostatic field, thereby reducing the ethylene adsorption heat.

[0188] In general, the present invention breaks through the dual-template method to synthesize the EMT / 13X mixed crystal molecular sieve with complete structure and high crystallinity based on EMT molecular sieve. The preparation process of the proposed molecular sieve adsorbent is shorter and has lower energy consumption. The prepared molecular sieve adsorbent has a larger specific surface area, higher adsorption capacity and purification depth of oxides, and lower adsorption heat. Its specific surface area is ≥450m 2 / g, ethylene adsorption heat ≤70℃, oxygenate adsorption capacity increased by more than 30%, purification depth can reach below 1ppb, suitable for the efficient removal of trace dimethyl ether, methanol, propionaldehyde and other non-polar or polar oxygenates in light olefins.

[0189] 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 a high-efficiency molecular sieve adsorbent for deep purification of oxygenated substances, characterized in that: The following steps are involved: (1) Aluminum source, silicon source, alkali source, template and water are uniformly mixed to obtain a crystallized lyogel, which is then subjected to microwave hydrothermal crystallization and then conventional hydrothermal crystallization after aging to obtain an EMT / 13X mixed crystal molecular sieve, which is then filtered to obtain a wet cake; (2) Dry the wet filter cake, add inorganic additives and pore-forming agents, mix evenly, roll granulate and dry; (3) The dried granules are placed in an oxygen-containing atmosphere and calcined to obtain an EMT / 13X composite molecular sieve adsorbent, which is the target product; The template agent is composed of template agent A and template agent B in a molar ratio of 6:4 to 8:2, wherein the template agent A is 18-crown-6 or 15-crown-5, and the template agent B is selected from one or a combination of triethylamine, n-butylamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, polyethylene glycol or polyquaternium-6.

2. The method for preparing a high-efficiency molecular sieve adsorbent for deep purification of oxygenates according to claim 1, characterized in that: The aluminum source is one or more of aluminum hydroxide, sodium metaaluminate, aluminum isopropoxide, aluminum sulfate and butyl-tert-aluminum; The silicon source is one or more of silica sol, sodium silicate, sodium water glass, and tetraethyl orthosilicate; The alkali source is sodium hydroxide.

3. The method for preparing a high-efficiency molecular sieve adsorbent for deep purification of oxygenates according to claim 1, characterized in that: The material ratio of the EMT / 13X mixed crystal molecular sieve in step (1) is as follows: the molar ratio of sodium oxide to aluminum oxide is 2-10, the molar ratio of silicon oxide to aluminum oxide is 6-20, the molar ratio of water to aluminum oxide is 200-430, and the molar ratio of template to aluminum oxide is 0.5-2.

4. The method for preparing a high-efficiency molecular sieve adsorbent for deep purification of oxygenates according to claim 1, characterized in that: In step (1), the aging conditions are: aging time 36 to 96 h, aging temperature is room temperature; The microwave hydrothermal crystallization conditions are as follows: microwave power of 300-600 W, crystallization temperature of 50-80 °C, and crystallization time of 0.5-4 h; The traditional hydrothermal crystallization conditions are: crystallization temperature 90~180 ℃, crystallization time 4~36 h.

5. The method for preparing a high-efficiency molecular sieve adsorbent for deep purification of oxygenates according to claim 1, characterized in that: In step (1), the thickness of the obtained wet filter cake is ≤2 cm and the water content is 55-65 wt%; In step (2), the drying conditions are: drying temperature is 40-80 °C, drying time is 4-24 h, and the moisture content of the filter cake after drying is 35-45 wt%.

6. The method for preparing a high-efficiency molecular sieve adsorbent for deep purification of oxygenates according to claim 1, characterized in that: In step (2), the inorganic additive is one or more of aluminum hydroxide, quick-de-powdering and pseudo-boehmite, and the amount of the inorganic additive accounts for 15-40 wt% of the dry basis of the final calcined product; The pore-forming agent is one or more of methyl cellulose, sesbania powder, maltodextrin, starch, carboxypropyl methyl cellulose and carboxyethyl cellulose, and the amount of the pore-forming agent accounts for 0.5-4 wt% of the dry basis of the final calcined product.

7. The method for preparing a high-efficiency molecular sieve adsorbent for deep purification of oxygenates according to claim 1, characterized in that: In step (3), the roasting process is: carried out in a gas environment with an oxygen content of ≥40%, the roasting temperature is 350~550℃, and the roasting time is 1~10 hours.

8. A high-efficiency molecular sieve adsorbent for deep purification of oxygenated substances, prepared by the preparation method according to any one of claims 1 to 7.

9. The use of the high-efficiency molecular sieve adsorbent for deep purification of oxygenates according to claim 8, characterized in that: The adsorbent is used for the efficient removal of non-polar or polar oxygenates in light olefins.

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