Crystallization apparatus for chloroiridic acid production

Abstract

This invention provides a crystallization device for the production of chloroiridium acid, including a crystallization vessel and a remelting cylinder disposed outside and connected to the crystallization vessel. The remelting cylinder includes a suction pipe extending from the side and communicating with the lower part of the crystallization vessel, a water distribution component located above the suction pipe for solution reflux, a second temperature control jacket sleeved on the outer surface for temperature control, a drive cylinder disposed at the center of the top of the remelting cylinder, a piston push plate slidably disposed inside the remelting cylinder and connected to the output end of the drive cylinder, a stirring component connected to the piston push plate for stirring the solution in the remelting cylinder, and a mother liquor replenishment port extending outward along the side of the remelting cylinder away from the suction pipe. The piston push plate is driven by the drive cylinder, and the suction pipe draws in the fine crystal solution in the lower part of the crystallization vessel. The fine crystals are then remelted in the remelting cylinder to redissolve into mother liquor, which is then introduced into the upper part of the crystallization vessel through the water distribution component for recrystallization.

Description

Technical Field

[0001] This invention relates to the field of chloroiridium acid production technology, and in particular to a crystallization device for chloroiridium acid production. Background Technology

[0002] Chloroiridic acid is an important precursor in the preparation of iridium-based catalysts, electrode coating materials, and other iridium compounds. In the production of chloroiridic acid, the purified mother liquor typically needs to be concentrated and crystallized to obtain chloroiridic acid hydrate crystals or high-concentration chloroiridic acid products. Crystallization equipment typically employs conventional stirred crystallizers or vacuum concentration crystallization.

[0003] The existing chloroiridium acid crystallization system suffers from a critical technological shortcoming: it is highly sensitive to supersaturation. The crystal nucleation and growth process has extremely low tolerance for changes in supersaturation, resulting in poor overall crystallization stability. In industrial production, even small fluctuations in process parameters such as cooling rate, solvent evaporation, stirring intensity, feed rate, and uneven system temperature can cause a sudden increase in localized or instantaneous supersaturation, disrupting the steady-state growth equilibrium of the crystals and triggering explosive homogeneous nucleation. This phenomenon leads to the rapid formation of numerous fine crystals within the system. These crystals cannot grow sufficiently and regularly, exhibiting problems such as small particle size, uneven particle size distribution, and irregular morphology. These fine crystals have a large specific surface area and high surface activity, readily adsorbing crystallization mother liquor containing impurity ions and acidic media. Conventional filtration and washing processes are insufficient to completely remove residual impurities, reducing product purity and crystallization yield while increasing feed viscosity and filtration resistance. In filtration and centrifugal separation processes, fine crystals are prone to aggregation and compaction, causing filter cloth blockage and filter cake caking. This significantly prolongs operation time, reduces production efficiency, and also leads to material retention losses, increasing production costs. Furthermore, the high surface energy and poor thermodynamic stability of fine crystals make them prone to adsorption, agglomeration, and clumping throughout the entire process of discharge, drying, and storage, and this clumping problem is difficult to reverse. The final product exhibits quality defects such as uneven particle size, poor flowability, and weak batch stability. This not only affects product appearance but also leads to uneven dissolution and reaction performance deviations in downstream applications such as catalysis and electroplating, severely restricting the product's high-end application value and significantly increasing the difficulty of production control and quality management. Summary of the Invention

[0004] Based on this, the purpose of this invention is to provide a crystallization device for the production of chloroiridic acid, so as to fundamentally solve the problem that the current crystallization device for the production of chloroiridic acid may produce a large number of small-diameter fine crystals in a short time due to improper control of supersaturation during the crystallization process. The fine crystals have small particle size, large specific surface area, are easy to carry mother liquor, increase filtration resistance, and are easy to stick together, leading to the agglomeration of subsequent products.

[0005] A crystallization apparatus for producing chloroiridic acid according to an embodiment of the present invention includes a crystallization vessel and a remelting cylinder disposed outside and connected to the crystallization vessel; The remelting cylinder includes a suction pipe extending from the side and communicating with the lower part of the crystallization vessel, a water distribution component located above the suction pipe for solution reflux, a second temperature control jacket sleeved on the outer surface for temperature control, a drive cylinder located at the center of the top of the remelting cylinder, a piston push plate slidably disposed in the remelting cylinder and connected to the output end of the drive cylinder, a stirring component connected to the piston push plate for stirring the solution in the remelting cylinder, and a mother liquor replenishment port extending outward along the side of the remelting cylinder away from the suction pipe. The piston pusher plate is driven by the drive cylinder, and the fine crystal solution in the lower part of the crystallization vessel is drawn by the suction pipe. The fine crystals are then redissolved in the redissolution cylinder to become mother liquor. After that, the mother liquor is introduced into the upper part of the crystallization vessel through the water distribution component and then recrystallized.

[0006] Furthermore, the suction tube includes at least one upper branch tube extending outward from the top for suctioning the solution, turbidity detection heads respectively embedded in the suction tube and the upper branch tube passage, and spherical crystal shields respectively sleeved at the suction ports of the suction tube and the upper branch tube for isolating coarse crystals.

[0007] Furthermore, the crystallization vessel includes a first temperature control jacket fitted on its outer surface, and a stirring shaft assembly that runs through the center of the top of the crystallization vessel and is used for stirring the solution.

[0008] Furthermore, the regions inside the crystallization vessel are arranged from top to bottom as a gas-liquid entrainment region, a nucleation control region, a central crystal growth region, a fine crystal suction region, and a coarse crystal sedimentation region, with the suction port of the suction pipe distributed in the fine crystal suction region and above.

[0009] Furthermore, the water distribution component includes an annular distribution pipe embedded in the crystallization vessel, multiple support plates extending outward from the outer edge of the annular distribution pipe and fixedly connected to the inner wall of the crystallization vessel, a drain port extending outward from the bottom of the annular distribution pipe for draining the solution, and an outer pipe assembly penetrating the crystallization vessel and used to connect the annular distribution pipe with the remelting cylinder.

[0010] Furthermore, the external pipe assembly includes a liquid delivery pipe, a temperature control component disposed in the middle section of the liquid delivery pipe and connected thereto, and a branch pipe that bypasses the temperature control component and connects the two ends of the liquid delivery pipe.

[0011] Furthermore, the temperature control component includes a temperature control cylinder connected to the liquid delivery pipe, an annular cooling plate disposed on the inner wall of the temperature control cylinder, a spiral mixing blade embedded in the temperature control cylinder, and an annular temperature guiding plate disposed at the inlet of the temperature control cylinder near the remelting cylinder.

[0012] Furthermore, the agitation component includes a support shaft movably embedded in the center of the piston pusher plate, an inner driven gear sleeved on the support shaft, a stirring assembly disposed at the bottom of the inner driven gear and connected in series through the support shaft, and a driving assembly disposed on one side of the inner driven gear for driving.

[0013] Furthermore, the drive assembly includes an auxiliary cylinder disposed at the top of the remelting cylinder and near the drive cylinder, a helical tube disposed at the output end of the auxiliary cylinder, a twisted rod screwed to the inner wall of the helical tube and connected to it for transmission, and an inner drive gear disposed at the bottom end of the twisted rod and linked with the inner driven gear.

[0014] Furthermore, the stirring assembly includes an annular frame disposed at the bottom end of the inner driven gear and coaxially disposed therewith, and multiple telescopic stirring rods extending outward along the side of the annular frame away from the inner driven gear.

[0015] Compared with the prior art, the crystallization equipment for producing chloroiridic acid in the above embodiments of the present invention uses a driving cylinder to drive a piston pusher plate, and a suction pipe to draw the fine crystal solution in the lower part of the crystallization vessel. After redissolving the fine crystals into mother liquor in the redissolution cylinder, the solution is introduced into the upper part of the crystallization vessel through a water distribution component for recrystallization. This solves the problem that the current crystallization equipment for producing chloroiridic acid may produce a large number of small-diameter fine crystals in a short time due to improper control of supersaturation during the crystallization process. The fine crystals have small particle size, large specific surface area, and are easy to carry mother liquor, increasing filtration resistance. They are also easy to stick together, leading to agglomeration of subsequent products. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the crystallization equipment for producing chloroiridic acid in an embodiment of the present invention; Figure 2 This is a partial cross-sectional structural diagram of the crystallization equipment for producing chloroiridic acid in an embodiment of the present invention; Figure 3 This is a partial cross-sectional schematic diagram of the crystallization vessel in the crystallization equipment for producing chloroiridic acid in an embodiment of the present invention; Figure 4 This is a partial structural diagram of the remelting cylinder and water distribution component in the crystallization equipment for producing chloroiridic acid in an embodiment of the present invention; Figure 5 This is a partial structural diagram of the remelting cylinder in the crystallization equipment for producing chloroiridic acid in an embodiment of the present invention; Figure 6 This is a partial structural schematic diagram of the agitation component in the crystallization equipment for producing chloroiridic acid in an embodiment of the present invention; Figure 7 This is a partial structural schematic diagram of the agitation component in the crystallization equipment for producing chloroiridic acid in an embodiment of the present invention; Figure 8 This is an enlarged structural diagram of section A of the crystallization equipment for producing chloroiridic acid in an embodiment of the present invention; Figure 9 This is a partial structural schematic diagram of the water distribution component in the crystallization equipment for producing chloroiridium acid in an embodiment of the present invention; Figure 10 This is a partial structural diagram of the temperature control component in the crystallization equipment for producing chloroiridic acid in an embodiment of the present invention; Figure 11 This is a partial structural diagram of the suction pipe in the crystallization equipment for producing chloroiridic acid in an embodiment of the present invention.

[0017] Explanation of key component symbols:

[0018] The following detailed description of the embodiments will further illustrate the present invention in conjunction with the above-described accompanying drawings. Detailed Implementation

[0019] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Several embodiments of the invention are illustrated in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

[0020] It should be noted that when a component is said to be "fixed to" another component, it can be directly on the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0022] Please see Figures 1 to 11The image shows a crystallization apparatus for producing chloroiridium acid according to an embodiment of the present invention. It includes a crystallization vessel 100 and a refluxing cylinder 200 disposed outside and connected to the crystallization vessel 100. The refluxing cylinder 200 includes a suction pipe 201 extending from its side and communicating with the lower part of the crystallization vessel 100; a water distribution component 300 located above the suction pipe 201 for solution reflux; a second temperature control jacket 204 fitted on its outer surface for temperature control; a drive cylinder 202 disposed at the center of the top of the refluxing cylinder 200; and a component slidably disposed inside the refluxing cylinder 200 and connected to the output end of the drive cylinder 202. The system includes a piston pusher plate 206, a stirring component 400 connected to the piston pusher plate 206 and used to stir the solution in the remelting cylinder 200, and a mother liquor replenishment port 205 extending outward from the side of the remelting cylinder 200 away from the suction pipe 201. The piston pusher plate 206 is driven by the drive cylinder 202, and the suction pipe 201 draws the fine crystal solution in the lower part of the crystallization vessel 100. After remelting in the remelting cylinder 200 to redissolve the fine crystals into mother liquor, it is introduced into the upper part of the crystallization vessel 100 through the water distribution component 300 for recrystallization.

[0023] Furthermore, the suction pipe 201 includes at least one upper branch pipe 2011 extending outward from the top for suctioning the solution, turbidity detection heads 2012 respectively embedded in the suction pipe 201 and the upper branch pipe 2011 passage, and spherical crystal-blocking covers 2013 respectively sleeved at the suction ports of the suction pipe 201 and the upper branch pipe 2011 for isolating coarse crystals. The crystallization vessel 100 includes a first temperature control jacket 101 sleeved on the outer surface, and a stirring shaft assembly 102 penetrating along the center of the top of the crystallization vessel 100 for stirring the solution. The suction ports of the suction pipe 201 are distributed in the fine crystal suction region 106 and above. The water distribution component 300 includes an annular distribution pipe 303 embedded in the crystallization vessel 100. Multiple support plates 304 extend outward from the outer edge of the annular distribution pipe 303 and are fixedly connected to the inner wall of the crystallization vessel 100; a drain port 305 extends outward from the bottom of the annular distribution pipe 303 for draining the solution; and an outer pipe assembly penetrates the crystallization vessel 100 and connects the annular distribution pipe 303 to the remelting cylinder 200. The outer pipe assembly includes a liquid delivery pipe 301, a temperature control component 500 disposed in the middle section of the liquid delivery pipe 301 and connected thereto, and a branch pipe 302 that bypasses the temperature control component 501 and connects to the two ends of the liquid delivery pipe 301. The temperature control component 500 includes a temperature control cylinder 501 connected to the liquid delivery pipe 301, an annular cooling plate 502 disposed on the inner wall of the temperature control cylinder 501, and a cooling plate embedded in the temperature control cylinder. The spiral mixing blade 503 inside the temperature control cylinder 501 and the annular temperature guiding plate 504 located at the inlet of the temperature control cylinder 501 near the remelting cylinder 200 are included. The stirring component 400 includes a support shaft 409 movably embedded in the center of the piston push plate 206, an inner driven gear 401 sleeved on the support shaft 409, a stirring assembly located at the bottom of the inner driven gear 401 and connected in series through the support shaft 409, and a driving assembly located on one side of the inner driven gear 401 for driving. The driving assembly includes an auxiliary cylinder 407 located at the top of the remelting cylinder 200 and near the driving cylinder 202, a spiral tube 406 located at the output end of the auxiliary cylinder 407, and a drive assembly screwed to the inner wall of the spiral tube 406 for transmission. The connecting twisted rod 405 and the inner driving gear 404 set at the bottom end of the twisted rod 405 and linked with the inner driven gear 401, the stirring assembly includes an annular frame 402 set at the bottom end of the inner driven gear 401 and coaxially arranged therewith, and multiple telescopic stirring rods 403 extending outward along the side of the annular frame 402 away from the inner driven gear 401. In some optional embodiments, the bottom end of the telescopic stirring rod 403 is provided with a counterweight block that abuts against the inner wall of the bottom of the remelting cylinder 200. While not affecting the subsequent rotation of the telescopic stirring rod 403 with the annular frame 402, the counterweight can also ensure the smooth extension and retraction of the telescopic stirring rod 403 and avoid structural jamming during the extension and retraction process.

[0024] It should be noted that the regions inside the crystallization vessel 100 are arranged from top to bottom as follows: gas-liquid entrainment region 103, nucleation control region 104, central crystal growth region 105, fine crystal suction region 106, and coarse crystal sedimentation region 107. Among them, the gas-liquid entrainment region 103 is located at the top of the crystallization vessel 100, which mainly realizes gas-liquid separation, intercepts droplets and fine foam generated by boiling, prevents the chloroiridium acid liquid from being lost with the gas phase, and at the same time buffers the fluctuation of the buffer surface, avoids the problem of violent boiling, and ensures the stability of the system inside the vessel. The nucleation control region 104 is located below the liquid surface, where the solution reaches a critical supersaturated state and generates the initial crystal nuclei. By controlling the nucleation rate and number of crystal nuclei through adjusting the operating conditions, concentrated burst nucleation is prevented, reducing the generation of ultrafine grains from the source, which is understandable to those skilled in the art. The central crystal growth region 105, as the core area for crystal growth, relies on a stable concentration, temperature, and flow field environment to allow crystal nuclei to grow continuously and uniformly, while promoting uniform solute diffusion, reducing the probability of impurity encapsulation, and ensuring regular crystal morphology and stable product quality. The fine crystal suction region 106 is connected to the remelting cylinder 200 through the suction pipe 201, and its main purpose is to target the suction of fine crystals. The coarse crystal sedimentation region 107... Located at the bottom of the crystallization vessel 100, the mature coarse crystals naturally settle and aggregate under gravity. The flow rate within this area is slow, minimizing disturbance to the crystal layer and achieving initial solid-liquid separation. This facilitates the subsequent discharge and processing of the finished crystals and mother liquor. Correspondingly, the agitator shaft assembly 102 within the crystallization vessel 100 primarily covers the nucleation control area 104, the central crystal growth area 105, and the fine crystal suction area 106. The agitation speed is also slow. In some optional embodiments, to improve the agitation quality, the agitator shaft assembly 102 is designed with an inner and outer double-helix blade design, such as... Figure 4 As shown, this can increase the contact area between the blades and the solution, improve the stirring quality, and ensure the subsequent solution crystallization efficiency.

[0025] In practical implementation, firstly, the operator can connect to external equipment through the gas-liquid interface at the top of the crystallization vessel 100 according to the gas-liquid ratio of the chloroiridic acid reaction process, and introduce the mother liquor into the crystallization vessel 100 according to the ratio to carry out the chloroiridic acid production crystallization operation. During the crystallization reaction, the operator can perform auxiliary crystallization operations by controlling the crystallization equipment for chloroiridic acid production. In some optional embodiments of the present invention, the controller can be set at any convenient location for the operator to operate on the crystallization equipment for chloroiridic acid production, and the controller can be an MCU (Microcontroller Unit). The controller (microcontroller unit) chip is used to control the crystallization equipment for chloroiridic acid production. The controller can also be electrically connected to the crystallization equipment, including wired and wireless connections. Wireless connections include, but are not limited to, Bluetooth, WiFi, IF radio frequency, and Zigbee. Wired connections include, but are not limited to, network communication lines connecting the crystallization equipment and the controller. Specifically, the controller controls the agitator shaft assembly 102 to initially stir the mother liquor in the crystallization vessel 100, and simultaneously controls the first temperature control jacket 101 to assist in the control of the crystallization process. The temperature inside the crystallizer 100 meets the crystallization temperature, causing the mother liquor to quickly become saturated and crystallize. During the process, considering that chloroiridium acid may produce a large number of small-diameter fine crystals in a short time due to improper control of supersaturation during crystallization, these fine crystals are completely suspended in the mother liquor and are mainly distributed in the nucleation control region 104, the middle crystal growth region 105, and the fine crystal suction region 106. Therefore, in some optional embodiments, the suction pipe 201 can be provided with multiple branch pipes that correspond to the nucleation control region 104, the middle crystal growth region 105, and the fine crystal suction region 106, respectively, so as to facilitate the targeted extraction of the mother liquor in the future.

[0026] Next, in the specific implementation of extracting the mother liquor from the crystallization vessel 100 through the remelting cylinder 200, the controller controls the drive cylinder 202 and drives the piston pusher plate 206 at its output end to move along the inner wall of the remelting cylinder 200. In some optional embodiments of the present invention, the piston pusher plate 206 may, but is not limited to, be a PFA plunger valve (both the valve body and the plunger are PFA); PTFE The V-shaped combination sealing ring is wear-resistant, corrosion-resistant, and leak-free; the zirconia ceramic guide sleeve prevents plunger wear and extends service life; its main purpose is to prevent reaction with chloroiridium acid. Then, under the drive of the piston push plate 206 and the drive cylinder 202, a negative pressure is generated in the remelting cylinder 200 to realize the suction operation of the mother liquor in the crystallization kettle 100. During the process of the mother liquor being introduced into the suction pipe 201 along the upper branch pipe 2011, the coarse crystals can also be isolated and filtered by the spherical crystal baffle 2013 so that the fine crystals that do not meet the volume requirement can be introduced. In addition, in some optional embodiments of the present invention, the use of the upper branch pipe 2011 can also be based on the turbidity detection head 2012 set on the current pipeline to monitor the turbidity of the mother liquor in the pipe in real time. It should be noted that the size of the fine crystal particles determines the turbidity of the mother liquor, and the turbidity detection head 2012 can control whether to use the current upper branch pipe 2011 according to the turbidity of the fine crystals.

[0027] Furthermore, after the mother liquor is introduced into the remelting cylinder 200, the operator can control the second temperature control jacket 204 through the controller to heat the solution in the remelting cylinder 200, so that the fine crystals in the mother liquor are heated and dissolved in the solution again. During the process, the piston push plate 206 is driven up and down, which can drive the inner drive gear 404 and the spiral rod 405 to slide up and down. During the sliding process, the spiral rod 405 and the solenoid 406 are threadedly driven, so that the driving force generated by the up and down sliding is applied to the spiral rod 405 to make it rotate axially, and drive the inner drive gear 404 to rotate. Then, the inner drive gear 404 drives the inner driven gear 401 to rotate, which drives the annular frame 402 and the telescopic stirring rod 403 at its bottom end to rotate, and stirs the mother liquor in the remelting cylinder 200 to help accelerate the fine crystals in the mother liquor and ensure that the fine crystals are fully dissolved.

[0028] Next, when the piston pusher plate 206 moves downward, the mother liquor, which has been fully dissolved in the remelting cylinder 200, can be reintroduced into the crystallization vessel 100 along the water distribution component 300, implementing a solution reflux operation. Specifically, the negative pressure generated by the downward movement of the piston pusher plate 206 draws the mother liquor from the remelting cylinder 200 to the delivery pipe 301. During this process, the solution will sequentially pass through one side of the delivery pipe 301 to the branch pipe 302 and then to the other side of the delivery pipe 301. Afterward, it enters the annular distribution pipe 303 for a diversion operation. The solution can be uniformly introduced into the crystallization vessel 100 in a ring shape through the drain port 305 at the bottom of the annular distribution pipe 303. It should be noted that the area corresponding to the bottom of the drain port 305 is the central crystal growth area 105. In addition, in some optional embodiments of the present invention, in order to avoid a large temperature difference between the mother liquor in the refluxing cylinder 200 and the mother liquor in the crystallization vessel 100 affecting subsequent crystallization, a temperature control component 500 is added to the liquid delivery pipe 301. The temperature control component 500 obtains the temperature of the mother liquor in the two liquid delivery pipes 301 in real time. Then, according to the temperature in the crystallization vessel 100, the temperature of the mother liquor discharged from the refluxing cylinder 200 is adjusted. It can be understood that when the detected temperature difference exceeds 5-10℃, the branch pipe 302 is closed, the temperature control cylinder 501 is opened and connected to the liquid delivery pipe 301, and the mother liquor is guided into the temperature control cylinder 501 to implement temperature regulation. After the temperature meets the discharge threshold, the liquid delivery pipe 301 is opened to guide the mother liquor into the crystallization vessel 100.

[0029] In summary, the crystallization equipment for producing chloroiridic acid in the above embodiments of the present invention drives the piston pusher plate 206 through the drive cylinder 202, and the suction pipe 201 draws the fine crystal solution in the lower part of the crystallization vessel 100. After redissolving the fine crystals into mother liquor in the redissolution cylinder 200, the solution is introduced into the upper part of the crystallization vessel 100 through the water distribution component 300 for recrystallization. This solves the problem that the current crystallization equipment for producing chloroiridic acid may produce a large number of small-diameter fine crystals in a short time due to improper control of supersaturation during the crystallization process. The fine crystals have small particle size, large specific surface area, and are easy to carry mother liquor, increasing filtration resistance. They are also easy to stick together, leading to agglomeration of subsequent products.

[0030] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0031] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A crystallization apparatus for the production of chloroiridium acid, characterized in that, It includes a crystallization vessel and a remelting cylinder disposed outside and connected to the crystallization vessel; The remelting cylinder includes a suction pipe extending from the side and communicating with the lower part of the crystallization vessel, a water distribution component located above the suction pipe for solution reflux, a second temperature control jacket sleeved on the outer surface for temperature control, a drive cylinder located at the center of the top of the remelting cylinder, a piston push plate slidably disposed in the remelting cylinder and connected to the output end of the drive cylinder, a stirring component connected to the piston push plate for stirring the solution in the remelting cylinder, and a mother liquor replenishment port extending outward along the side of the remelting cylinder away from the suction pipe. The piston pusher plate is driven by the drive cylinder, and the fine crystal solution in the lower part of the crystallization vessel is drawn by the suction pipe. The fine crystals are then redissolved in the redissolution cylinder to become mother liquor. After that, the mother liquor is introduced into the upper part of the crystallization vessel through the water distribution component and then recrystallized.

2. The crystallization equipment for producing chloroiridium acid according to claim 1, characterized in that, The suction tube includes at least one upper branch tube extending outward from the top for suctioning the solution, turbidity detection heads respectively embedded in the suction tube and the upper branch tube passage, and spherical crystal shields respectively sleeved at the suction ports of the suction tube and the upper branch tube for isolating coarse crystals.

3. The crystallization equipment for producing chloroiridium acid according to claim 1, characterized in that, The crystallization vessel includes a first temperature control jacket fitted on its outer surface, and a stirring shaft assembly that runs through the center of the top of the crystallization vessel and is used for stirring the solution.

4. The crystallization equipment for producing chloroiridium acid according to claim 3, characterized in that, The regions inside the crystallization vessel are arranged from top to bottom as a gas-liquid entrainment region, a nucleation control region, a central crystal growth region, a fine crystal suction region, and a coarse crystal sedimentation region. The suction ports of the suction pipe are distributed in the fine crystal suction region and the regions above it.

5. The crystallization equipment for producing chloroiridium acid according to claim 3, characterized in that, The water distribution component includes an annular distribution pipe embedded in the crystallization vessel, multiple support plates extending outward from the outer edge of the annular distribution pipe and fixedly connected to the inner wall of the crystallization vessel, a drain port extending outward from the bottom of the annular distribution pipe for draining the solution, and an outer pipe assembly penetrating the crystallization vessel and used to connect the annular distribution pipe with the remelting cylinder.

6. The crystallization equipment for producing chloroiridium acid according to claim 5, characterized in that, The external pipe assembly includes a liquid delivery pipe, a temperature control component disposed in the middle section of the liquid delivery pipe and connected thereto, and a branch pipe that bypasses the temperature control component and connects the two ends of the liquid delivery pipe.

7. The crystallization equipment for producing chloroiridium acid according to claim 6, characterized in that, The temperature control component includes a temperature control cylinder connected to the liquid delivery pipe, an annular cooling plate disposed on the inner wall of the temperature control cylinder, a spiral mixing blade embedded in the temperature control cylinder, and an annular temperature guiding plate disposed at the inlet of the temperature control cylinder near the remelting cylinder.

8. The crystallization equipment for producing chloroiridium acid according to claim 7, characterized in that, The agitation component includes a support shaft movably embedded in the center of the piston pusher plate, an inner driven gear sleeved on the support shaft, a stirring assembly disposed at the bottom of the inner driven gear and connected in series through the support shaft, and a driving assembly disposed on one side of the inner driven gear for driving.

9. The crystallization equipment for producing chloroiridium acid according to claim 8, characterized in that, The drive assembly includes an auxiliary cylinder disposed at the top of the remelting cylinder and near the drive cylinder, a helical tube disposed at the output end of the auxiliary cylinder, a twisted rod screwed to the inner wall of the helical tube and connected to it for transmission, and an inner drive gear disposed at the bottom end of the twisted rod and linked with the inner driven gear.

10. The crystallization equipment for producing chloroiridium acid according to claim 9, characterized in that, The stirring assembly includes an annular frame coaxially disposed at the bottom end of the inner driven gear, and multiple telescopic stirring rods extending outward along the side of the annular frame away from the inner driven gear.

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