Small-particle-size hexagonal crystal system lanthanum cerium precursor preparation device
By combining water boiling alkali conversion to fluorination and mechanical crushing processes with a jacketed insulated reactor and plate heat exchanger, the problem of uneven particle size of cerium-based rare earth polishing powder precursors in existing technologies has been solved. This has enabled the efficient preparation of small-particle-size hexagonal lanthanum-cerium precursors, improving product performance and reducing environmental impact.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-08
- Publication Date
- 2026-04-10
AI Technical Summary
Existing ball milling equipment has difficulty achieving particle sizes below 5 μm when preparing cerium-based rare earth polishing powder precursors, and the fluorinating agent does not act evenly, resulting in poor product consistency and affecting the quality of the polishing powder.
By employing a process of boiling alkali to convert to fluorination and mechanical crushing, combined with a jacketed insulated reactor and a plate heat exchanger, the precursor of rare earth polishing powder is pretreated. Through boiling alkali to convert to fluorination and mechanical crushing, a small-particle-size hexagonal lanthanum-cerium precursor with high crystallinity and uniform fluoride ion reaction is prepared, and thermal energy and water resources are recovered and utilized.
It improves the crystallinity and particle uniformity of the precursor, reduces pretreatment costs, reduces environmental pollution, and enhances the performance of the polishing powder.
Smart Images
Figure CN224100703U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to rare earth polishing powder preparation technical field, concretely to a kind of small particle size hexagonal crystal system lanthanum cerium precursor preparation device. BACKGROUND
[0002] The main component of cerium-based rare earth polishing powder is CeO2. Due to its superior physical properties and chemical activity, such as high hardness, moderate cutting rate, low surface roughness, and small heat generated during grinding process, it has shown great potential in the development process of modern industrial manufacturing refinement and high-end. Since the mid-20th century, it has been used for ordinary glass polishing. After continuous iteration and development, it has gradually replaced some polishing materials, and the market share has increased significantly.
[0003] With the increasing importance of cerium-based polishing powder industry in global high-end manufacturing, the market has more stringent requirements for the grinding performance and grinding effect of its products. Higher level of chemical mechanical polishing material is an effective method to meet this requirement. Related studies have shown that the polishing performance and surface quality of the ground workpiece of cerium-based rare earth polishing powder are mainly affected by its microstructure, phase composition, and particle size distribution. The industry generally fluorinates and wet-mills the polishing powder precursor. On the one hand, by introducing fluoride ions, the phase composition of the polishing powder product can be improved. On the other hand, after wet-milling and crushing, undesirable structural defects left over from the precursor generation process can be generated and developed, improving the structural stability of the precursor and making the fluorination agent more evenly distributed, thereby promoting the conversion of the phase to fluorine oxide, which is beneficial to improving the grinding capacity of the powder, and ultimately improving the polishing powder product. However, in actual operation, it is found that the particle size limit of the slurry is basically 5um during the front-end wet-milling of the rare earth polishing powder precursor using general ball milling equipment. To obtain a ball-milled product below 5um, a large amount of time and energy is required. Moreover, because the fluorocarbonate structure generated by the addition of fluorination agent and lanthanum cerium carbonate has significantly improved strength compared to carbonate, the particle size of carbonate decreases rapidly during the ball-milling process, resulting in uneven particle size of the precursor and uneven distribution of the fluorination agent, poor product consistency, and ultimately affecting the quality of the cerium-based polishing powder product. Therefore, new methods of pretreatment and fluorination of polishing powder precursors are of great significance. SUMMARY
[0004] The utility model aims at providing a small particle size hexagonal crystal system lanthanum cerium precursor preparation device, which obtains small particle size hexagonal crystal system lanthanum cerium precursor with high crystallinity, uniform fluoride ion reaction, small particles and uniform morphology through water boiling alkali conversion and fluorination, mechanical crushing and adjustment process. At the same time, the cost of pretreatment and crushing of the precursor is reduced, the recycling of water resources, heat energy and reagents during the fluorination process is realized, and the adverse effects on the external environment are reduced. Thus, the problems raised in the background technology are solved.
[0005] The utility model discloses a technical scheme as follows:
[0006] A small particle size hexagonal system lanthanum cerium precursor preparation device, including raw material mixing tank 1, jacketed reaction kettle 2, snake tube type heat exchanger 3, plate type heat exchanger 4, horizontal sand mill 5 and spray dryer 6, the raw material mixing tank 1 bottom liquid outlet is communicated with the liquid inlet of jacketed reaction kettle 2 and plate type heat exchanger 4 respectively, and the bottom discharge port of jacketed reaction kettle 2 is communicated with horizontal sand mill 5 and snake tube type heat exchanger 3 respectively, the outlet of horizontal sand mill 5 is communicated with spray dryer 6, the steam exhaust port set up at the top of jacketed reaction kettle 2 is connected to plate type heat exchanger 4 through pipeline, and the two outlets of snake tube type heat exchanger 3 are communicated to jacketed reaction kettle 2 and plate type heat exchanger 4 respectively through pipeline, and the two outlets of plate type heat exchanger 4 are all communicated to raw material mixing tank 1.
[0007] The spray dryer 6 includes a blower 601, a natural gas combustion chamber 602, a drying tower 603, a cyclone 604 and an induced draft fan 605, the feed inlet of the drying tower 603 is communicated with the outlet of the horizontal sand mill 5, the air outlet of the blower 601 is communicated with the air inlet of the natural gas combustion chamber 602, the outlet of the natural gas combustion chamber 602 is communicated to the hot air inlet of the drying tower 603, the bottom discharge port of the drying tower 603 is communicated with the inlet of the cyclone 604, the dust discharge port of the cyclone 604 is connected with the induced draft fan 605, and the air outlet of the induced draft fan 605 is communicated to a pipeline inlet of the plate type heat exchanger 4 through a pipeline.
[0008] A transmission motor a101 is installed on the top of the raw material mixing tank 1, and the output shaft of the transmission motor a101 is connected with the stirring shaft of the stirrer arranged in the raw material mixing tank 1.
[0009] The top of the jacketed reaction kettle 2 is provided with a transmission motor b201, and the output shaft of the transmission motor b201 is connected with the stirring shaft of the stirrer arranged in the jacketed reaction kettle 2; and the jacketed reaction kettle 2 is externally provided with a heat insulation plate 202, and the material of the heat insulation plate 202 is polypropylene plastic.
[0010] The steam exhaust port of the jacketed reaction kettle 2, the condensate water outlet of the snake tube type heat exchanger 3 and the tail gas discharge port of the spray dryer 6 are all connected with the same inlet of the plate type heat exchanger 4 through a pipeline. The material in the raw material mixing tank is preheated, the condensate water of the plate type heat exchanger 4 returns to the raw material mixing tank 1, and the recovered material, water resource and related reagent are recovered. Another inlet of the plate type heat exchanger 4 is communicated to the bottom liquid outlet of the raw material mixing tank 1.
[0011] The heat source pipeline inlet of the snake tube heat exchanger 3 is connected to a steam pipeline, the heat source pipeline outlet of the snake tube heat exchanger 3 is communicated to the plate heat exchanger 4, the material passage outlet of the snake tube heat exchanger 3 is communicated to the upper portion of the jacketed heat preservation reaction kettle 2, and the material passage inlet of the snake tube heat exchanger 3 is communicated to the discharge port at the bottom of the jacketed heat preservation reaction kettle 2.
[0012] The horizontal sand mill 5 is filled with 0.5-1.5 mm zirconium balls as grinding materials to mechanically crush large particles in the water-boiled fluoridation slurry.
[0013] In summary, due to the adoption of the technical scheme, the beneficial effects of the present application are as follows:
[0014] The present application utilizes the water-boiled alkali conversion fluorination process to pretreat the rare earth polishing powder precursor, and through the water-boiled alkali conversion fluorination, mechanical crushing and adjustment process, a cerium-based rare earth polishing powder precursor with high crystallinity, uniform fluorine ion reaction, small particle size and uniform morphology is obtained, the pretreatment and crushing cost of the precursor is reduced, the fluorine ion reaction is complete, which is more conducive to the preparation of subsequent materials, and the product performance is improved. BRIEF DESCRIPTION OF DRAWINGS
[0015] Figure 1 The present application utilizes the water-boiled alkali conversion fluorination process to pretreat the rare earth polishing powder precursor, and through the water-boiled alkali conversion fluorination, mechanical crushing and adjustment process, a cerium-based rare earth polishing powder precursor with high crystallinity, uniform fluorine ion reaction, small particle size and uniform morphology is obtained, the pretreatment and crushing cost of the precursor is reduced, the fluorine ion reaction is complete, which is more conducive to the preparation of subsequent materials, and the product performance is improved.
[0016] Fig. 1 shows a raw material mixing tank; 101, a transmission motor a; 2, a jacketed heat preservation reaction kettle; 201, a transmission motor b; 202, an insulation plate; 3, a snake tube heat exchanger; 4, a plate heat exchanger; 5, a horizontal sand mill; 6, a spray dryer; 601, a blower; 602, a natural gas combustion chamber; 603, a drying tower; 604, a cyclone; and 605, an induced draft fan. DETAILED DESCRIPTION
[0017] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and completely below in combination with the drawings and specific data in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application.
[0018] Therefore, the following detailed description of the embodiments of the present application is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.
[0019] Embodiment 1
[0020] As Figure 1 , the embodiment provides a small particle size hexagonal lanthanum cerium precursor preparation device, which comprises a raw material mixing tank 1, a jacketed heat preservation reaction kettle 2, a snake tube type heat exchanger 3, a plate type heat exchanger 4, a horizontal sand mill 5 and a spray dryer 6. The bottom liquid outlet of the raw material mixing tank 1 is communicated with the liquid inlet of the jacketed heat preservation reaction kettle 2 and the plate type heat exchanger 4 respectively. The bottom discharge port of the jacketed heat preservation reaction kettle 2 is communicated with the horizontal sand mill 5 through a pipeline to realize material discharge and also communicated with the snake tube type heat exchanger 3 to realize heating. The horizontal sand mill 5 is filled with 0.5-1.5 mm zirconium balls as grinding material to mechanically ball mill and crush large particles in the water boiling fluorination slurry, so as to improve the slurry particle size and morphology uniformity. The outlet of the horizontal sand mill 5 is communicated with the spray dryer 6 through a pipeline. The spray dryer 6 dehydrates and dries the fluorination slurry. The steam discharge port arranged at the top of the jacketed heat preservation reaction kettle 2 is connected to the plate type heat exchanger 4 through a pipeline. The steam discharge port at the top of the jacketed heat preservation reaction kettle 2 discharges the reagent high-temperature steam contained in the reaction kettle. The two outlets of the snake tube type heat exchanger 3 are respectively communicated to the jacketed heat preservation reaction kettle 2 and the plate type heat exchanger 4 through pipelines. The outlets of the two passages of the plate type heat exchanger 4 are both communicated to the upper part of the raw material mixing tank 1.
[0021] The spray dryer 6 comprises a blower 601, a natural gas combustion chamber 602, a drying tower 603, a cyclone 604 and an induced draft fan 605. The feed inlet of the drying tower 603 is communicated with the outlet of the horizontal sand mill 5 through a pipeline. The air outlet of the blower 601 is communicated with the air inlet of the natural gas combustion chamber 602. The outlet of the natural gas combustion chamber 602 is communicated to the hot air inlet of the drying tower 603. The bottom discharge port of the drying tower 603 is communicated with the inlet of the cyclone 604. The dust discharge port of the cyclone 604 is connected with the induced draft fan 605. The air outlet of the induced draft fan 605 is communicated to the pipeline inlet of the plate type heat exchanger 4 through a pipeline.
[0022] A transmission motor a101 is installed on the top of the raw material mixing tank 1. The output shaft of the transmission motor a101 is connected with the stirring shaft of the stirrer arranged inside the raw material mixing tank 1. The stirring in the raw material mixing tank 1 can realize the sufficient mixing of the rare earth polishing powder raw material, the fluorination agent and the PH regulator in the tap water system.
[0023] A transmission motor b201 is arranged at the top of the jacketed heat preservation reaction kettle 2. The output shaft of the transmission motor b201 is connected with the stirring shaft of the stirrer arranged inside the jacketed heat preservation reaction kettle 2. The stirring can make the materials in the reaction kettle keep uniform heating in the water boiling fluorination process. The jacketed heat preservation reaction kettle 2 is externally provided with a heat insulation plate 202. The material of the heat insulation plate 202 is polypropylene plastic, which can insulate the heat loss in the reaction kettle.
[0024] The steam exhaust port of the jacketed reaction kettle 2, the condensate outlet of the coil heat exchanger 3 and the tail gas discharge port of the spray dryer 6 are connected with the same inlet of the plate heat exchanger 4 through pipelines. The material in the raw material mixing tank is preheated, and the condensate water of the plate heat exchanger 4 returns to the raw material mixing tank 1, so that the material, water resources and related reagents are recovered, resource comprehensive utilization is realized, and the adverse effects on the external environment are reduced. Another inlet of the plate heat exchanger 4 is connected to the liquid outlet at the bottom of the raw material mixing tank 1.
[0025] The heat source pipeline inlet of the coil heat exchanger 3 is connected to the steam pipeline, that is, the heat source of the coil heat exchanger 3 is steam, the heat source pipeline outlet of the coil heat exchanger 3 is connected to the plate heat exchanger 4, the material passage outlet of the coil heat exchanger 3 is connected to the upper part of the jacketed reaction kettle 2, and the material passage inlet of the coil heat exchanger 3 is connected to the discharge port at the bottom of the jacketed reaction kettle 2.
[0026] One of the inlet of the plate heat exchanger 4 is connected to the liquid outlet at the bottom of the raw material mixing tank 1 through a pipeline, and the other inlet is connected to the steam exhaust port of the jacketed reaction kettle 2, the condensate outlet of the coil heat exchanger 3 and the tail gas discharge port (the air outlet of the induced draft fan 605) of the spray dryer 6 through pipelines, respectively. The two outlet of the plate heat exchanger 4 are connected to the raw material mixing tank 1.
[0027] The device can be used for water boiling fluorination of cerium-based rare earth polishing powder precursors. Through pH value and fluorination temperature control of the fluorination system, and then supplemented by mechanical crushing means, the precursor has high crystallinity, consistent crystal structure, uniform morphology and small particle size, so that the fluorine ion reaction is complete, which is more conducive to the preparation of subsequent materials and improves the product performance. The device process can realize the recycling of water resources, heat energy and reagents, reduces the generation of industrial three wastes in the preparation process, and thus reduces the adverse effects on the external environment.
Claims
1. A small particle size hexagonal lanthanum cerium precursor preparation device, comprising a raw material slurry tank (1), a jacketed reaction kettle (2), a snake tube heat exchanger (3), a plate heat exchanger (4), a horizontal sand mill (5) and a spray dryer (6), characterized in that, The raw material mixing tank (1) is communicated with the jacketed heat preservation reaction kettle (2) and the plate heat exchanger (4) through the liquid outlet at the bottom, the bottom of the jacketed heat preservation reaction kettle (2) is communicated with the horizontal sand mill (5) and the coil heat exchanger (3), the outlet of the horizontal sand mill (5) is communicated with the spray dryer (6), the steam outlet at the top of the jacketed heat preservation reaction kettle (2) is connected to the plate heat exchanger (4) through a pipeline, the two outlets of the coil heat exchanger (3) are communicated to the jacketed heat preservation reaction kettle (2) and the plate heat exchanger (4) through pipelines, and the two outlets of the plate heat exchanger (4) are communicated to the raw material mixing tank (1). 2.The small particle size hexagonal lanthanum cerium precursor preparation device according to claim 1, characterized in that: The spray dryer (6) comprises an air blower (601), a natural gas combustion chamber (602), a drying tower (603), a cyclone (604) and an induced draft fan (605), the feed inlet of the drying tower (603) is communicated with the outlet of the horizontal sand mill (5), the air outlet of the air blower (601) is communicated with the air inlet of the natural gas combustion chamber (602), the outlet of the natural gas combustion chamber (602) is communicated with the hot air inlet of the drying tower (603), the bottom outlet of the drying tower (603) is communicated with the inlet of the cyclone (604), the dust outlet of the cyclone (604) is connected with the induced draft fan (605), and the air outlet of the induced draft fan (605) is communicated with one pipeline inlet of the plate heat exchanger (4) through a pipeline. 3.The device for preparing small particle size hexagonal lanthanum cerium precursor according to claim 1, characterized in that: The driving motor a (101) is installed at the top of the raw material mixing tank (1), and the output shaft of the driving motor a (101) is connected with the stirring shaft of the stirrer arranged in the raw material mixing tank (1). 4.The device for preparing small particle size hexagonal lanthanum cerium precursor according to claim 1, characterized in that: The driving motor b (201) is arranged at the top of the jacketed heat preservation reaction kettle (2), and the output shaft of the driving motor b (201) is connected with the stirring shaft of the stirrer arranged in the jacketed heat preservation reaction kettle (2); and the jacketed heat preservation reaction kettle (2) is externally provided with the heat insulation plate (202) made of polypropylene plastic. 5.The device for preparing small particle size hexagonal lanthanum cerium precursor according to claim 1, characterized in that: The steam outlet of the jacketed heat preservation reaction kettle (2), the condensate outlet of the coil heat exchanger (3) and the tail gas discharge port of the spray dryer (6) are all communicated with the same inlet of the plate heat exchanger (4) through pipelines. 6.The device for preparing small particle size hexagonal lanthanum cerium precursor according to claim 1, characterized in that: The heat source pipeline inlet of the coil heat exchanger (3) is connected to a steam pipeline, and the material passage outlet of the coil heat exchanger (3) is communicated to the upper portion of the jacketed heat preservation reaction kettle (2). 7.The device for preparing small particle size hexagonal lanthanum cerium precursor according to claim 1, characterized in that: The horizontal sand mill (5) is filled with 0.5-1.5 mm zirconium balls as grinding materials to mechanically crush large particles in the water-boiled fluorinated slurry.