A constant-temperature high-activity molecular sieve ion exchange process

Abstract

The application discloses a kind of constant temperature high activity molecular sieve ion exchange process, belong to adsorbent synthesis and preparation field.Using the reaction tank of unique design, filter loading disc, vacuum buffer tank regulation and control and multiple collection barrels, a constant temperature exchange process is formed, efficient mass transfer of solid phase material and liquid phase exchange liquid is realized, multistage utilization, exchange degree and exchange efficiency are improved.Combining with multiple control methods, compared with traditional intermittent exchange and column exchange, it has better exchange rate and solid phase recovery rate, at the same time, with valve group timing, collection barrel polling, pneumatic actuator automatic unloading and other control methods, greatly reduce the degree of operation complexity, reduce cost, realize multidimensional application.In industrial production, for different functional molecular sieve, adsorbent synthesis and preparation method, it has great applicability and practicality.

Description

Technical Field

[0001] This invention belongs to the field of molecular sieve synthesis and preparation, specifically relating to a constant-temperature, highly active molecular sieve ion exchange process. Background Technology

[0002] Molecular sieves have significant applications in industrial chemical engineering, VOCs treatment, water purification, separation and purification, and biomedicine. Based on the synthesis of different types of structures, their functions can be achieved by modifying the metal ions on their silicon-aluminum framework, such as 3A, 4A, 5A, and molecular sieves.

[0003] Molecular sieve adsorption is a novel method and will likely become the mainstream separation and purification method in the future chemical industry. It primarily uses molecular sieves as adsorbents, which are packed into appropriate adsorption devices. Taking the separation of mixed cresols as an example, molecular sieve-type adsorbents can be synthesized based on the molecular size of m- / p-cresols. Suitable desorbents can be selected, and corresponding process controls can be implemented to achieve the separation effect. Finally, the desorbent is removed, and methylphenol products with a purity of over 99.5% are separated and refined from the mixed cresols. The desorbent can be recovered and reused, and the entire process has almost no environmental cost. Therefore, the synthesis and preparation of functional adsorbents will be the main technological barrier.

[0004] In recent years, molecular sieve adsorption has been increasingly applied in traditional material separation fields. For example, patent CN114008222A previously used ion exchange of Ca... 2+ Resins, combined with DAC column methods, using BaY, KBaX, etc., are applied to second-generation sugar-liquid phase separation. They are also applied in emerging fields, such as patent CN116750776A, which uses exchanged Li-A type molecular sieves for lithium electrolyte water removal, employing an on-site molding and re-exchange method.

[0005] As is well known, molecular sieves can selectively adsorb because, compared to activated carbon, they not only have well-developed pores, but more importantly, they can achieve different surface structures and pore sizes by changing the bound metal ions. In the preparation process of molecular sieve adsorbents, ion exchange is generally used to replace the metal ions with different ones to achieve different adsorption functions and application scenarios.

[0006] Traditional ion exchange of molecular sieves generally employs batch reactor exchange, while column exchange, due to its high bed resistance, is primarily used for raw molecular sieve powders. Currently, column exchange is more common because it eliminates the need for repeated filtration and slurry preparation compared to batch exchange. It typically requires the addition of binders such as silica sol, kaolin, and attapulgite, followed by balling, extrusion, and spraying to form the molecular sieve before column exchange. Similarly, wet granular materials exhibit poor flowability and bed pressure drop issues. The introduction of amorphous clay components further complicates the exchange process. Once dynamic equilibrium is reached during ion exchange, further increases in exchange rate become difficult. For example, when attapulgite is introduced into oxygen-generating adsorbents, inorganic alkalis cannot be used for adjustment, as this easily leads to caking and other problems.

[0007] Therefore, there is an urgent need to invent and develop a process to solve these problems. Summary of the Invention

[0008] In response to the shortcomings of existing technologies and equipment issues, this invention discloses a constant-temperature, highly active molecular sieve ion exchange process.

[0009] To achieve the above objectives, the present invention adopts the following technical solution: It discloses a process for the synthesis and preparation of highly active molecular sieves, combining multiple control methods, using a multi-stage exchange method at a constant temperature to improve exchange efficiency. Combined with a uniquely designed filter carrier, utilizing channels and pores under micro-vacuum negative pressure, the filter cloth layer is adhered to form a vacuum cavity, delaying the liquid outflow time, increasing the efficient contact mass transfer between the exchange liquid and the molecular sieve adsorbent, and improving exchange efficiency.

[0010] Specifically, a constant-temperature, high-activity molecular sieve ion exchange process system includes a reaction device, a buffer device, and a recovery device.

[0011] The reaction apparatus includes a reaction vessel, inside which are a stirring paddle and a nozzle, and a lower cover is provided at the bottom. The lower cover adopts a concave disc-shaped tray structure, and the opening and closing angle α of the lower cover is controlled between 15 and 75º by a telescopic cylinder and a crank.

[0012] The buffer device includes buffer tank A and buffer tank B. The drain port of the tray is connected in series with buffer tank A and buffer tank B via a hose. Buffer tank A is equipped with a vacuum gas pipeline, and buffer tank B is equipped with a compressed gas pipeline. The recycling device includes n collection tanks. Buffer tank B is connected to the inlet pipe of each collection tank through the inlet liquid path. The outlet pipe of each collection tank is connected to the nozzle through the outlet liquid path, the circulation pump, and the circulation liquid path.

[0013] The filter carrier disc is embedded in the concave disc of the tray and adopts a convex structure. The protrusion has multiple concentric grooves with a width of 1~2mm and a depth of 0.5~1mm. The grooves have through holes with a diameter of 0.5~2mm. There are no less than 2 holes on each 1 / 4 ring of the groove. The non-protrusion surface of the filter carrier disc has O-shaped grooves. The filter cloth layer is fixed to the O-shaped grooves by O-rings.

[0014] n is an integer not less than 5.

[0015] Furthermore, the reaction vessel 1 has an enamel-lined inner wall with a jacket, or is made of fiberglass, and is heated by a heating medium to maintain a constant temperature. The upper cover is sealed and locked to the main body of the reaction vessel 1 using a handwheel and a connecting bolt. The upper surface of the upper cover includes a molecular sieve powder feeding port and an isolation sleeve for driving the agitator coupling. A fixed nozzle is located below the upper cover.

[0016] The lower cover has a hinge on one side and an automatic hook on the other side to support the filter tray, with a gap between the tray and the filter tray.

[0017] The impeller 2 has one or more of the following blade types: anchor type, frame type, ribbon type, etc.

[0018] Further, open the ball valve on the vacuum gas line and close the ball valve on the compressed gas line. The vacuum gas flow carries the filtrate from the reaction vessel through the drain port into the buffer device, temporarily storing the filtrate in buffer tank B. Only a small amount or no filtrate enters buffer tank A. Then, the reverse operation is performed, allowing compressed air to send the filtrate in buffer tank B to the recovery device without disrupting the system vacuum. This alternating process ensures continuous recycling of the exchange liquid. When the exchange liquid reaches its maximum number of exchanges, it no longer needs to be recovered; simply open the manual valve to drain it from the system.

[0019] The buffer tank A and buffer tank B are used together. Based on the discharge flow rate of the reaction tank, the liquid accumulation time in buffer tank B is determined. Simultaneously, the current occupancy of the collection tank needs to be considered to determine the discharge time of the accumulated liquid in buffer tank B. Sufficient time is provided to ensure the continuity and integrity of the process.

[0020] Specifically, the ratio of the time for liquid collection to liquid drainage is 2.5 to 5:1.

[0021] Furthermore, the recovery device consists of multiple collection tanks, which are independent of each other and are heated by a jacket. By changing the switching state of the valve group on the inlet and outlet pipes, the filtrate from different time segments in the buffer device can be collected. At the same time, the filtrate from different time segments in the recovery device is sent back to the reaction tank by a circulating pump and flows to the upper liquid surface of the raw powder wet material through the nozzle.

[0022] The height of the protrusion is 1 / 50 to 1 / 100 of the maximum thickness of the filter tray, and the diameter of the filter tray is the same as the inner diameter of the lower diameter-changing region of the reaction vessel. The filter tray is embedded in the tray. The non-protrusion surface of the filter tray does not have grooves or openings, but is designed with O-rings to fix the filter cloth layer. O-rings also serve as a seal between the reaction vessel and the filter tray. The diameter of the non-protrusion portion of the filter tray is the same as the outer diameter of the lower diameter-changing region of the reaction vessel.

[0023] The filter carrier is made of non-metallic material, including but not limited to one or more of polyetheretherketone, polytetrafluoroethylene, polyurethane, and polyimide. It may also contain a small amount of one or more of carbon fiber, glass fiber, graphite, and copper powder.

[0024] Furthermore, the nozzle adopts a ring-shaped design with duckbill-shaped openings facing the inner wall of the reaction tank 1. The exchange liquid drawn from the recovery device by the circulation pump is dispersed here and flows down the wall. The nozzle has no fewer than four duckbill-shaped openings.

[0025] Furthermore, the stirring speed ranges from 180 to 300 r / min.

[0026] Furthermore, the constant temperature range is 70~90°C.

[0027] Furthermore, the volumetric flow rate of the circulating pump is 1 / 10 to 1 / 25 of the volumetric flow rate of the filtrate discharged from the reaction tank. This can be adjusted according to the process. If a simultaneous liquid inlet and outlet method is used, in addition to the first discharge after slurrying, the subsequent exchange process and water washing process require liquid inlet and outlet to be carried out according to the aforementioned volumetric flow rate ratio to ensure the solid cake remains moist and prevents drying, cracking, or turbulence.

[0028] The control methods include, but are not limited to, one or more of the following: the vacuum traction liquid flow, the circulation pump injecting the exchange liquid, and the state of the stirring paddle. This invention provides a process method for a constant-temperature, highly active molecular sieve ion exchange system, comprising the following steps: Molecular sieve powder is loaded into the reaction vessel, and the exchange liquid in the collection tank is injected through a circulating pump. Stirring is started, and a heating medium is introduced into the jacket of the reaction vessel to heat the exchange material. Stirring is continued for 30~120 min. A negative pressure is created in buffer tanks A and B through a vacuum gas pipeline. The exchanged filtrate enters the buffer tank and the pressure in the buffer tank is adjusted through a compressed gas pipeline to transport the exchanged filtrate to the collection tank. After ion exchange, the molecular sieve is washed with deionized water and then discharged from the bottom of the reaction vessel. The exchange rules for the exchange solution are as follows: n collection buckets are named 1#, 2#, 3#, i#...n# from left to right. Among them, collection bucket 1# contains fresh exchange solution and is used for the n-2th exchange in the next exchange cycle. Collection bucket i# contains the exchange solution from the i-1th exchange and is used for the ni-1th exchange in the next exchange cycle. Collection bucket n-1# contains the exchange solution from the n-2th exchange and is used for the molecular formula powder to be slurried and discharged in the next exchange cycle. Collection bucket n# contains deionized water and is used to clean the molecular sieve after the exchange is completed. 2≤i≤n-2.

[0029] Furthermore, the process method of the isothermal high-activity molecular sieve ion exchange process system includes the following steps: Step 1: At the beginning, the molecular sieve powder is fed into the reaction tank through the feeding port (12). The exchange liquid in the collection tank is injected into the reaction tank by the circulating pump. The slurry is started and continues for 30~120 min. The heating medium is introduced into the jacket of the reaction tank to provide a constant temperature environment with a temperature range of 70~90°C. Step 2: After pulping, the filtrate is carried into buffer tank B and buffer tank A by negative pressure airflow with a vacuum degree of -5±0.5 Kpa, and then enters the collection tank in sequence for heat preservation. The exchange liquid in the next collection tank is introduced through the circulation pump. At this time, the stirring speed is reduced to 1 / 10 to 1 / 50 of the previous speed. Step 3: After normal continuous operation, the exchange solution with the highest number of exchanges should be used first. The n collection bins are named 1#, 2#, 3#, i#…n# from left to right; Collection tank #1 holds fresh exchange solution; named primary exchange solution; used for the next cycle's (n-2)th exchange. Collection tank #n-1 collects the tail liquid from the n-2th exchange, used for the next cycle's raw powder pulping. The nth collection tank is defined as collection tank #n, used to hold deionized water, used for washing after the last exchange. Wash water from two consecutive washes is recycled to collection tank #n for washing after the next exchange. When n=5 Collection container #1: Contains and stores fresh exchange medium; named primary exchange medium; used for the third exchange in the next cycle; #2 Collection Bucket: This bucket collects the tailings from the first exchange and names it the second exchange solution; it is used for the second exchange in the next cycle. #3 Collection Bucket: This bucket collects the tailings from the second exchange and names it the third exchange solution; it is used for the first exchange in the next cycle. Collection bucket #4: Collects the tail liquid from the third exchange, named the fourth exchange liquid; used for the raw powder stirring solution in the next cycle; 5# Collection Bucket: Collects wash water; used for cleaning the molecular sieve after exchange. After going through the above sequence, the blocky material with a solid content of about 75-82% is compressed by the brake mechanism driven by compressed air to contract and open to a suitable angle, and then the filter cloth and the material are discharged together.

[0030] Meanwhile, the above-mentioned process rules and methods are also applied to the ion exchange of the shaped molecular sieve, including but not limited to tableting, rolling, extrusion, spraying, and dripping.

[0031] The beneficial effects of the present invention: The present invention discloses a constant temperature high-activity molecular sieve ion exchange process, wherein the three main control methods, multiple sets of collection tanks, vacuum buffer tanks and pneumatic actuators form a constant temperature exchange process.

[0032] Controlled by valve groups, the collection tank operates in a polling manner, with a circulating pump progressively exchanging the molecular sieve adsorbent in multiple stages, thus utilizing the exchange liquid and significantly reducing waste liquid discharge. Combined with a uniquely designed reaction vessel and filter tray, a vacuum buffer tank regulates the contact time between the exchange liquid and the wet material. Simultaneously, a pneumatic actuator controls the release and collection of materials, facilitating mass transfer and exchange with solid materials. Compared to traditional processes, this significantly reduces operational complexity and costs, enabling multi-dimensional applications. It has great applicability and practicality in industrial production, especially in the synthesis and preparation of various functional molecular sieves and adsorbents. Attached Figure Description

[0033] Figure 1 This is a process diagram of a constant-temperature, highly active molecular sieve ion exchange process.

[0034] Figure 2 yes Figure 1 Top view of the filter tray.

[0035] Figure 3 yes Figure 1 The main view of the filter carrier disk.

[0036] In the diagram, 1. Reaction vessel; 2. Stirring paddle; 3. Motor; 4. Upper cover; 5. Lower cover; 6. Telescopic rod cylinder; 7. Crank rod; 8. Hoses; 9-1. Buffer tank A; 9-2. Buffer tank B; 10. Vacuum circuit; 11. Compressed air circuit; 12-1. First liquid circuit ball valve; 12-2. Second liquid circuit ball valve; 12-3. Third liquid circuit ball valve; 13-1. First air circuit ball valve; 13-2. Second air circuit ball valve; 14-1. Inlet ball valve of #1 tank; 14-2. Outlet ball valve of #1 tank; 14-3. Inlet ball valve of #2 tank; 14-4. Outlet ball valve of #2 tank; 14-5. Inlet ball valve of #3 tank; 14-6. Outlet ball valve of #3 tank; 14-7. Inlet ball valve of #4 tank; 14-8. Outlet ball valve of #4 tank; 14-9. Inlet ball valve of #0 tank; 14 -10. Ball valve at the outlet of barrel #0; 15-1. First manual ball valve; 15-2. Second manual ball valve; 15-3. Third manual ball valve; 15-4. Fourth manual ball valve; 16. Nozzle; 17. Feeding port; 18. Circulating pump; 19. Liquid inlet path; 20. Liquid outlet path; 21. Circulating liquid path; 22. Collection barrel; 23. Handwheel union bolt; 24. Isolation sleeve; 25. Filter tray; 26. Tray; 27. Drain outlet; 28. Boss; 29. ​​Channel; 30. Groove; 31. Filter cloth layer; 32. Hole. Detailed Implementation

[0037] The following description, in conjunction with the accompanying drawings, describes preferred embodiments in a more accessible manner so that the advantages and features of the present invention can be more readily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0038] Figure 1 A constant-temperature, high-activity molecular sieve ion exchange process system is shown in the figure. This system includes a reaction apparatus, a buffer apparatus, and a recovery apparatus. The reaction apparatus includes a reaction vessel 1, which contains a stirring paddle 2 and a nozzle 16. An upper cover 4 is installed on the top, and the upper cover 4 is sealed and locked to the main body of the reaction vessel 1 using a handwheel and connecting bolts. The upper cover 4 has a feeding port 17 and an isolation sleeve 24 for driving the coupling of the stirring paddle 2. The nozzle 16 is located on the lower surface of the upper cover 4. A lower cover 5 is installed at the bottom of the reaction vessel 1. The lower cover 5 adopts a concave disc-shaped tray 26 structure, connected to the reaction vessel on one side by a hinge, and an automatic hook structure on the other side. A telescopic cylinder 6 is fixed to the reaction vessel 1, and the opening angle α of the lower cover 5 is controlled between 15 and 75º by a crank 7. The buffer device includes buffer tank A9-1 and buffer tank B9-2. The drain port 27 of the tray 26 is connected in series with buffer tank A9-1 and buffer tank B9-2 via hose 8. Buffer tank A9-1 is equipped with a vacuum gas pipeline 10, and buffer tank B9-2 is equipped with a compressed gas pipeline 11.

[0039] The recycling device includes five collection tanks 22. A buffer tank B9-2 is connected to the inlet pipe of each collection tank 22 via an inlet liquid passage 19. The outlet pipe of each collection tank 22 is connected to a nozzle 16 via an outlet liquid passage 20, a circulation pump 18, and a circulation liquid passage 21. A filter tray 25 is embedded in the concave disc of a tray 26 and has a convex structure. Multiple concentrically distributed channels 29 are formed on the protrusions 28, and multiple through holes 32 are provided on the channels 29. O-ring grooves 30 are provided on the non-protrusion surfaces of the filter tray 25, and the filter cloth layer 31 is fixed to the O-ring grooves 30 by O-ring rubber rings.

[0040] The agitator 2 is driven by the motor 3. The vacuum gas pipeline 10 is connected to the vacuum pump, the compressed gas pipeline 11 is connected to the air compressor, the fresh exchange liquid storage tank is connected to the inlet liquid pipeline 19, and the outlet pipeline of the buffer tank B is connected to the manual drain pipe.

[0041] Each collection tank 22 is equipped with a liquid ball valve on its inlet and outlet pipes, outlet liquid path 20, inlet liquid path 19, circulating liquid path 21, hose 8, and outlet pipes of buffer tank A and buffer tank B. Vacuum gas path 10 and compressed gas path 11 are each equipped with a gas ball valve. Specific valve numbers are as follows: Figure 1 As shown. Example 1

[0042] Adopting such Figure 1 As shown, the technical parameters are as follows: Reactor volume: laminated glass, φ320x600mm, 50L; Stirring paddle: made of metal with PTFE coating, 220mm wide x 250mm high, frame type, with a spiral band 350mm from the bottom of the paddle, 60mm wide; Buffer tanks A and B: φ360mm, 25L, spherical; Filter tray: polytetrafluoroethylene, φ295x120mm, pores φ2±0.5mm, 1920 in total, channel width 1.8±0.5mm, depth 0.8±0.5mm, 20 in total; spacing 3.5±0.5mm; Filter cloth layer: Polypropylene industrial filter cloth (fitted to the filter bosses, spread outwards and fixed by O-rings), 750A (density), plain weave, 300-350 mesh; Collection buckets: 5 in total, named 1#, 2#, 3#, 4#, and 0# respectively; φ300x450mm, 20 L; Water circulating vacuum pump: Model 2BV2061, flow rate 52 M³ / h 3 / H, vacuum degree -10 Kpa (adjustable); Air compressor: FB50A model, theoretical flow rate 280 L / min, pressure 0.8 MPa (adjustable); The following specific plan will be adopted:

[0043] Step 1, Pulping

[0044] The lower cover 5 is closed, and the filter cloth has been installed. 1.2 kg of NaY raw powder is added through the feeding port. The circulating pump is started for 5 minutes at 1 L / min to pump deionized water from collection tank #0. Then, the circulating pump is started for 10 minutes at 2.2 L / min to add about 15 kg of solution from the third exchange tail liquid from collection tank #3. The temperature is raised to 85-90℃, and the mixture is continuously stirred at a speed of 208 r / min.

[0045] Step 2, Exchange

[0046] In collection tank #1, the exchange solution (20 kg of 10 wt% potassium sulfate solution) is injected via the third manual ball valve 15-3. For other initial applications, the solution is also fresh. The exchange rules are followed, and used exchange solutions are recycled. Buffer tanks A and B can be used for temporary storage to avoid conflicts before being sent to the corresponding collection tank. As subsequent batches of wet material need to be exchanged increase, the principle of "the exchange solution with the most exchanges is used first" is adopted.

[0047] That is, the first time collecting bucket #1 Reduce the stirring speed to 12 r / min, turn on the vacuum pump, and use the first gas path ball valve 13-1 to collect the filtrate, which is the exchange tail liquid. Store it in the waste liquid tank through the first manual ball valve 15-1 for later treatment, or use it for other molecular sieve exchange liquids such as 3A.

[0048] Subsequently, the tertiary exchange liquid in collection tank #3 was heated to a constant temperature, and the wet material in the reaction vessel was exchanged for the first time using a circulating pump with an average flow rate of 2.7 L / min. Afterward, the stirring speed was maintained at 20 r / min, and the vacuum pump traction pressure was controlled at -6 kPa. The filtrate discharge volume flow rate was approximately 2.7 L / min. The recovered liquid temporarily stored in buffer tanks A and B was then transferred to collection tank #4 by compressed air at 0.23 MPa and ball valve 13-2 in the second air path. The filtrate is the tail liquid of the tertiary exchange and is used for dry powder pulping.

[0049] Similarly, the secondary exchange liquid in collection tank #2 is heated to a constant temperature to perform a second exchange on the wet material in the reaction tank. The filtrate is the tertiary exchange liquid, which is stored in collection tank #3 for the first exchange of the wet material.

[0050] Similarly, the primary exchange solution in collection tank #1 is heated to a constant temperature to perform a third exchange on the wet material in the reaction vessel. The filtrate is the primary exchange solution, which is stored in collection tank #2 for the second exchange of the wet material.

[0051] This process is repeated to complete the three-level exchange.

[0052] Step 3 Washing

[0053] After the above is completed, drain the exchange solution. Then, the circulation pump intermittently pumps 3.2 L / min of deionized water from collection tank #0 twice. Similarly, the filtrate is recovered to collection tank #0.

[0054] Step 4: Collection

[0055] After going through the above sequence, the blocky material with a solid content of about 75-82wt% is discharged along with the filter cloth layer by the extension cylinder 6 driven by compressed air at 0.6Mpa and opened to a suitable angle.

[0056] After drying at 105±5℃ for 24 hours, it becomes KY type adsorbent A. Example 2

[0057] Referring to Example 1, using the same process, KX adsorbent B was prepared from NaX molecular sieve as the raw material. Example 3

[0058] Referring to Example 1, in the final step 4 of Example 2, it is not necessary to open the tray. The washed wet material is retained, and the same process is used to sequentially exchange with 20wt% ammonium sulfate solution, and 0.25wt% ammonia water and 5wt% lithium hydroxide solution are used. During this process, 0.25wt% ammonia water and 0.05wt% lithium hydroxide solution are used respectively to adjust the pH value of the exchange solution to 5-12, and Li-X adsorbent C is prepared. Example 4

[0059] Referring to Examples 1 and 2, the raw powder was 4A molecular sieve, and the same process was used to prepare Li-A adsorbent D by sequentially passing through 8.5wt% potassium sulfate, 18.5wt% ammonium sulfate, and 4.2wt% lithium hydroxide solution.

[0060] Comparative Example 1

[0061] Using the same raw materials as in Implementation 1, granulated into particles of φ0.5-φ0.8mm, with the same exchange solution concentration and temperature, a traditional column exchange system was employed. The adsorption column specifications were φ78x800mm, 4L, fixed with flanges at both ends, and equipped with an H-tree type 8-stage distributor. Each end was filled with 50mm long φ3mm glass bulbs, and the volumetric hourly space velocity was 3.5H⁺. -1 The exchange ratio is 30-35 times the bed volume. During disassembly, localized caking was found, requiring purging with heated airflow to facilitate unloading; this was identified as KY-type adsorbent E.

[0062] Comparative Example 2

[0063] Using the same powdered raw material as in Example 1, with the same exchange solution concentration and temperature, a traditional batch exchange was conducted in a 50L glass reactor at 90 rpm. After stirring for 45 minutes at the same temperature, the mixture was discharged, filtered using a filter press, and then returned to the reactor. This process was repeated six times. The solid phase recovery rate was 67.32% for KY-type adsorbent F. Example 5

[0064] Exchange rate (%): The changes in metal ion content before and after adsorbents A, B, C, D, E, and F were analyzed using X-ray fluorescence spectrometry (XRF) and the ratios were calculated. Specific surface area S BET (m 2 / g): The specific surface area of ​​adsorbents A, B, C, D, E, and F was analyzed using the Mack ASAP2460 model.

[0065] Adsorption capacity τ (mg / g): Using the methods in patent documents CN115420074B, CN114100591B, and CN113834293B, after dehydration and activation of adsorbents A, B, C, and D, the water content was ≤0.5wt%, the adsorbate was Cyclo-C6, the test temperature was 30±5℃, and the partial pressure value P / P0=2.1.

[0066] Table 1. Example Data Table

[0067] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A constant-temperature, highly active molecular sieve ion exchange process system, comprising a reaction device, a buffer device, and a recovery device, characterized in that, The reaction device includes a reaction vessel (1) with a jacket. The reaction vessel (1) is equipped with a stirring paddle (2) and a nozzle (16) inside. A lower cover (5) is provided at the bottom. The lower cover (5) adopts a concave disc-shaped tray (26) structure. The opening and closing angle α of the lower cover (5) is controlled between 15-75º by a telescopic cylinder (6) and a crank (7). The buffer device includes buffer tank A (9-1) and buffer tank B (9-2). The drain port (27) of the tray (26) is connected in series with buffer tank A (9-1) and buffer tank B (9-2) via hose (8). Buffer tank A (9-1) is provided with a vacuum gas pipeline (10), and buffer tank B (9-2) is provided with a compressed gas pipeline (11). The recycling device includes n collection tanks (22), and the buffer tank B (9-2) is connected to the inlet pipe of each collection tank (22) through the inlet liquid path (19). The outlet pipe of each collection tank (22) is connected to the nozzle (16) through the outlet liquid path (20), the circulation pump (18), and the circulation liquid path (21). The filter tray (25) is embedded in the concave disc of the tray (26) and adopts a convex structure. The boss (28) has multiple concentric grooves (29) with a width of 1~2mm and a depth of 0.5~1mm. The grooves (29) have through holes (32) with a diameter of 0.5~2mm. There are no less than 2 holes (32) on each 1 / 4 ring of the groove (29). The non-bore surface of the filter tray (25) has an O-shaped groove (30). The filter cloth layer (31) is fixed to the O-shaped groove (30) by an O-ring. n is an integer not less than 5.

2. The ion exchange process system according to claim 1, characterized in that, The height of the boss (28) is 1 / 50 to 1 / 100 of the maximum thickness of the filter carrier (25), and the diameter of the filter carrier (25) is the same as the inner wall diameter of the variable diameter area at the bottom of the reaction vessel (1).

3. The ion exchange process system according to claim 1 or 2, characterized in that, The nozzle (16) adopts an annular structure with no less than 4 duckbill-shaped openings.

4. The ion exchange process system according to claim 1 or 2, characterized in that, The blades of the stirring paddle (2) are one or more of the following: anchor type, frame type, and ribbon type blades. The filter carrier (25) is made of non-metallic material.

5. The process method of the ion exchange process system according to claim 1 or 2, characterized in that, Includes the following steps: Molecular sieve powder is loaded into the reaction vessel, and the exchange liquid in the collection tank is injected through the circulation pump. Stirring is started, and a heating medium is introduced into the jacket of the reaction vessel to heat the exchange material. Stirring is continued for 30~120 min. A negative pressure is created in buffer tank A (9-1) and buffer tank B (9-2) through vacuum gas pipeline (10). The exchanged filtrate enters the buffer tank, which is called liquid collection. The pressure in the buffer tank is adjusted through compressed gas pipeline (11) to transport the exchanged filtrate to the collection bucket, which is called liquid discharge. After ion exchange, the molecular sieve is washed with deionized water and then discharged from the bottom of the reaction vessel. The exchange rules for the exchange solution are as follows: n collection buckets are named 1#, 2#, 3#...i#...n# from left to right. Among them, collection bucket 1# contains fresh exchange solution and is used for the n-2th exchange in the next exchange cycle. Collection bucket i# contains the exchange solution from the i-1th exchange and is used for the ni-1th exchange in the next exchange cycle. Collection bucket n-1# contains the exchange solution from the n-2th exchange and is used for the molecular sieve powder to be slurried and discharged in the next exchange cycle. Collection bucket n# contains deionized water and is used to clean the molecular sieve after the exchange is completed. 2≤i≤n-2, The ratio of the time for liquid collection to liquid drainage is 2.5 to 5:

1.

6. The process method according to claim 5, characterized in that, The stirring speed range is 180~300 r / min.

7. The process method according to claim 5, characterized in that, The heating temperature is 70~90℃.

8. The process method according to claim 5, characterized in that, The volumetric flow rate of the circulating pump is 1 / 10 to 1 / 25 of the volumetric flow rate of the filtrate discharged from the reaction tank (1).

9. The process method according to any one of claims 5-7, characterized in that, The exchange steps are as follows: Step 1: At the beginning, the molecular sieve raw powder is loaded into the reaction tank through the feeding port (17). The exchange liquid in the n-1# collection tank is injected into the reaction tank by the circulating pump. Stirring is started and continued for 30~120min. The jacket of the reaction tank is circulated with heating medium to provide a constant temperature environment of 70~90℃. Step 2: After pulping, the filtrate is carried into buffer tank B and buffer tank A by negative pressure airflow with a vacuum degree of -5±0.5 Kpa, and then enters the collection tank in sequence for heat preservation. The exchange liquid in the n-2# collection tank is introduced through the circulation pump. At this time, the stirring speed is reduced to 1 / 10~1 / 50 of the previous speed. Step 3: After normal continuous operation, the exchange solution with the highest number of exchanges should be used first. The n collection buckets are named 1#, 2#, 3#…i#…n# from left to right; Collection tank #1 contains fresh exchange solution, named the first exchange solution, and is used for the (n-2)th exchange in the next cycle. Collection tank #n-1 collects the tail liquid from the (n-2)th exchange and is used for the raw powder stirring solution in the next cycle. Collection tank #i contains the (i-1)th exchange solution and is used for the (ni-1)th exchange in the next exchange cycle. The nth collection tank is defined as collection tank #n, which contains deionized water and is used for washing after the last exchange. The washing water from two consecutive washes is recycled to collection tank #n and used for washing after the next exchange cycle. When n=5 Collection container #1: Used to store fresh exchange solution, named primary exchange solution; Used for the third exchange in the next cycle; Collection bucket #2: This collection bucket collects the tailings from the first exchange and names it the second exchange solution. Used for the second exchange in the next cycle; Collection bucket #3: This collection bucket collects the tailings from the secondary exchange and names it the tertiary exchange solution. Used for the first exchange in the next cycle; Collection bucket #4: Collects the tailings from the third exchange, named the fourth exchange solution; Used for pulping raw powder in the next cycle; 5# Collection Bucket: Collects wash water; used for cleaning the molecular sieve after exchange. After going through the above sequence, the blocky material with a solid content of about 75-82% is discharged along with the filter cloth by the compression air-driven telescopic cylinder (6) after it contracts and opens to a suitable angle.

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