CN110980788A - Method for preparing superfine dysprosium oxide - Google Patents
Method for preparing superfine dysprosium oxide Download PDFInfo
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- CN110980788A CN110980788A CN201911379825.8A CN201911379825A CN110980788A CN 110980788 A CN110980788 A CN 110980788A CN 201911379825 A CN201911379825 A CN 201911379825A CN 110980788 A CN110980788 A CN 110980788A
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Abstract
The invention discloses a method for preparing superfine dysprosium oxide, which comprises the following steps: (1) stirring ammonia water for 5min, adding dysprosium chloride feed liquid, wherein the molar ratio of dysprosium chloride to ammonia water is 1 (3-4), stirring for 10min after feeding is finished, and adjusting the pH value to 6-7 by using ammonia water to obtain a colloidal solution; (2) heating an oxalic acid solution to 50-80 ℃ under the stirring condition, preserving heat, then adding the oxalic acid solution into a colloidal solution, stirring for 10min after the oxalic acid solution is added, standing for clarification, filtering to obtain a precipitate, washing the precipitate with high-purity water for 2-3 times, then washing with ethanol, and performing suction filtration to obtain a filter cake; (3) and drying the filter cake at 60 ℃ for 8-12 h, then crushing, burning at 850 ℃ for 2h, and naturally cooling to room temperature to obtain the ultrafine dysprosium oxide. The invention not only has simple process and low cost, but also improves the purity and quality of dysprosium oxide products.
Description
Technical Field
The invention belongs to the technical field of rare earth material preparation, and particularly relates to a method for preparing superfine dysprosium oxide.
Background
With the rapid development of high and new technology industries, rare earth products are more and more widely applied, for example, the application of rare earth oxide ultrafine powder in the fields of aviation, universe, atomic energy, ceramic industry and the like shows excellent performance. For example, dysprosium oxide can be used as a raw material for preparing metal dysprosium, glass, an additive for neodymium iron boron permanent magnets, and also can be used in metal halogen lamps, magneto-optical memory materials, yttrium iron or yttrium aluminum garnet and atomic energy industries. Dysprosium oxide is used as an additive of a neodymium-iron-boron permanent magnet, about 2-3% of dysprosium is added into the magnet to improve the coercive force of the magnet, the dysprosium oxide becomes a necessary additive element with the increase of the demand of neodymium-iron-boron magnets, but the grade of the dysprosium oxide needs to be about 95-99.9%, and the demands on indexes such as purity of dysprosium oxide products, physical properties of particles and the like are higher and higher with the increase of the demand of the dysprosium oxide.
The dysprosium oxide obtained by different dysprosium oxide synthesis methods has different particle morphology and specific surface area, so that the different particle morphology and specific surface area determine the properties of the final dysprosium oxide material, and especially, the dysprosium oxide after being ultrafined shows many characteristics such as small-size effect, high specific surface effect, quantum effect, extremely strong light, electricity, magnetic property, superconductivity, high chemical activity and the like, the performance and functions of the material can be greatly improved, a plurality of new materials are developed, and the development of the preparation method of the ultrafine dysprosium oxide with simple process and low cost has important application value.
Disclosure of Invention
Aiming at the defects, the invention discloses a method for preparing ultrafine dysprosium oxide, which has simple process and low cost.
The invention is realized by adopting the following technical scheme:
a method for preparing ultra-fine dysprosium oxide comprises the following steps:
(1) stirring ammonia water for 5min, adding dysprosium chloride feed liquid, wherein the molar ratio of dysprosium chloride to ammonia water is 1 (3-4), stirring for 10min after feeding is finished, and adjusting the pH value to 6-7 by using ammonia water to obtain a colloidal solution;
(2) weighing an oxalic acid solution according to the weight ratio of dysprosium oxide to oxalic acid being 1 (1.7-2.1), heating the oxalic acid solution to 50-80 ℃ under the stirring condition, preserving heat, adding the oxalic acid solution into the colloidal solution obtained in the step (1), stirring for 10min after the oxalic acid solution is added, standing, clarifying, filtering to obtain a precipitate, washing the precipitate with high-purity water for 2-3 times, then washing with ethanol, and performing suction filtration to obtain a filter cake;
(3) and (3) drying the filter cake obtained in the step (2) at 60 ℃ for 8-12 h, then crushing, burning at 850 ℃ for 2h, and naturally cooling to room temperature to obtain the ultrafine dysprosium oxide.
Furthermore, the concentration of the ammonia water is 3.0-15.0 mol/L.
Furthermore, the concentration of dysprosium chloride in the dysprosium chloride feed liquid is 0.448-1.597 mol/L.
Further, the stirring speed in the step (1) is 200-600 r/min.
Further, the stirring speed in the step (2) is 200-600 r/min.
Furthermore, the concentration of the oxalic acid is 10-20 mol/L.
Further, ammonia water is taken in the step (1), stirred for 5min, and then dysprosium chloride feed liquid is added at a constant speed, wherein the adding time is controlled to be 25-100 min.
Further, the oxalic acid solution in the step (2) is added into the colloidal solution at a constant speed, and the adding time is controlled to be 20-100 min.
Further, the high-purity water in the step (2) is the pure water with the conductivity less than or equal to 20 Mus/M and the resistivity more than or equal to 5M omega cm after the raw water is treated.
The main chemical reactions taking place in the present invention are as follows:
(1) and (3) dysprosium hydroxide precipitation: DCl3+3NH3H2O→D(OH)3↓+3NH4Cl
(2) Oxalate precipitation: d (OH)3+H2C2O4+nH2O→D2(C2O4)3·nH2O↓+6H2O
(3) Burning decomposition: 2D2(C2O4)3·nH2O+3O2→2D2O3+12CO2↑+2nH2O
Compared with the prior art, the technical scheme has the following beneficial effects:
1. the invention adopts ammonia water to convert dysprosium ions in dysprosium chloride feed liquid into dysprosium hydroxide precipitates, strictly limits the molar ratio and the pH value of dysprosium chloride and ammonia water, not only ensures that dysprosium ions are completely precipitated due to excessive ammonia water, but also controls the amount of residual hydroxyl ions in the solution, prevents excessive oxalic acid from being consumed due to the reaction of acid-base neutralization in the subsequent oxalic acid conversion step, and increases the production cost.
2. In the invention, oxalic acid is added into the initial stage of the colloidal solution containing dysprosium hydroxide, and the oxalic acid reacts with excessive ammonia water to generate ammonium oxalate so that the colloidal solution contains ammonium ions, the change sensitivity of the precipitation saturation of dysprosium oxalate is reduced, the nucleation speed is high, and the generated precipitate of dysprosium oxalate is more stable and has better uniformity; meanwhile, the oxalic acid is heated to 50-80 ℃ before being added, the reaction speed of the hot oxalic acid and dysprosium hydroxide can be increased, and small-granularity precipitates can be obtained.
3. The invention respectively controls the adding time of the dysprosium chloride feed liquid and the oxalic acid solution, so that the dysprosium chloride feed liquid and the oxalic acid solution can be correspondingly added into the ammonia water and the colloidal solution for reaction at a reasonable speed, and precipitates with uniform granularity are obtained; because the too fast particle dispersibility that generates of feed rate is poor, easily the reunion, form the flocculent precipitate, the particle diameter of granule is inhomogeneous moreover, and feed rate is too slow can make the particle that generates low, the nucleation is fast in the supersaturation degree of solution, the particle diameter of granule is big, and the settling time is long, reduces production efficiency, increases the production energy consumption.
4. The method has the advantages of simplicity, short period, low cost and high production efficiency, is beneficial to large-scale production of the high-purity and good-quality ultrafine dysprosium oxide, improves the performance and the function of a dysprosium oxide material, and expands the application field of the dysprosium oxide material.
Detailed Description
The invention is further illustrated by the following examples, which are not to be construed as limiting the invention thereto. The specific experimental conditions and methods not indicated in the following examples are generally conventional means well known to those skilled in the art.
Example 1:
a method for preparing ultra-fine dysprosium oxide comprises the following steps:
(1) stirring 5.0mol/L ammonia water for 5min, adding dysprosium chloride feed liquid at a constant speed, controlling the adding time to be 50min, controlling the molar ratio of dysprosium chloride to ammonia water to be 1:3.3, stirring for 10min at the speed of 400r/min after the feeding is finished, and adjusting the pH value to be 6.5 by using the ammonia water to obtain a colloidal solution; the concentration of dysprosium chloride in the dysprosium chloride feed liquid is 0.897 mol/L;
(2) weighing an oxalic acid solution according to the weight ratio of dysprosium oxide to oxalic acid of 1:1.9, heating the oxalic acid solution to 70 ℃ under the stirring condition of 400r/min, preserving heat, then adding the oxalic acid solution into the colloidal solution obtained in the step (1) at a constant speed, controlling the adding time to be 25min, stirring the oxalic acid solution for 10min after the adding is finished, standing for clarification, filtering to obtain a precipitate, washing the precipitate with high-purity water for 3 times, then washing with ethanol, and performing suction filtration to obtain a filter cake; the concentration of the oxalic acid is 20 mol/L; the high-purity water is the pure water with the conductivity less than or equal to 20 mu s/M and the resistivity more than or equal to 5M omega cm after the raw water is treated;
(3) and (3) drying the filter cake obtained in the step (2) at 60 ℃ for 10h, then crushing, burning at 850 ℃ for 2h, and naturally cooling to room temperature to obtain the ultrafine dysprosium oxide.
According to the method for preparing the ultrafine dysprosium oxide, the average particle size D50 of the obtained ultrafine dysprosium oxide is 2.24 um.
Example 2:
a method for preparing ultra-fine dysprosium oxide comprises the following steps:
(1) stirring 3.75mol/L ammonia water for 5min, adding dysprosium chloride feed liquid at a constant speed, controlling the adding time to be 50min, controlling the molar ratio of dysprosium chloride to ammonia water to be 1:3.5, stirring for 10min at the speed of 400r/min after the feeding is finished, and adjusting the pH value to 7 by using the ammonia water to obtain a colloidal solution; the concentration of dysprosium chloride in the dysprosium chloride feed liquid is 0.598 mol/L;
(2) weighing an oxalic acid solution according to the weight ratio of dysprosium oxide to oxalic acid of 1:2.0, heating the oxalic acid solution to 60 ℃ under the stirring condition of 400r/min, preserving heat, then adding the oxalic acid solution into the colloidal solution obtained in the step (1) at a constant speed, controlling the adding time to be 35min, stirring the oxalic acid solution for 10min after the adding is finished, standing for clarification, filtering to obtain a precipitate, washing the precipitate with high-purity water for 2 times, then washing with ethanol, and performing suction filtration to obtain a filter cake; the concentration of the oxalic acid is 15 mol/L; the high-purity water is the pure water with the conductivity less than or equal to 20 mu s/M and the resistivity more than or equal to 5M omega cm after the raw water is treated;
(3) and (3) drying the filter cake obtained in the step (2) at 60 ℃ for 12h, then crushing, burning at 850 ℃ for 2h, and naturally cooling to room temperature to obtain the ultrafine dysprosium oxide.
According to the method for preparing the ultrafine dysprosium oxide, the average particle size D50 of the obtained ultrafine dysprosium oxide is 2.44 um.
Example 3:
a method for preparing ultra-fine dysprosium oxide comprises the following steps:
(1) stirring 3.0mol/L ammonia water for 5min, adding dysprosium chloride feed liquid at a constant speed, controlling the adding time to be 100min, controlling the molar ratio of dysprosium chloride to ammonia water to be 1:4, stirring at the speed of 300r/min for 10min after the feeding is finished, and adjusting the pH value to 6.5 by using the ammonia water to obtain a colloidal solution; the concentration of dysprosium chloride in the dysprosium chloride feed liquid is 0.795 mol/L;
(2) weighing an oxalic acid solution according to the weight ratio of dysprosium oxide to oxalic acid of 1:1.8, heating the oxalic acid solution to 50 ℃ under the stirring condition of 500r/min, preserving heat, then adding the oxalic acid solution into the colloidal solution obtained in the step (1) at a constant speed, controlling the adding time to be 20min, stirring the oxalic acid solution for 10min after the adding is finished, standing for clarification, filtering to obtain a precipitate, washing the precipitate with high-purity water for 3 times, then washing with ethanol, and performing suction filtration to obtain a filter cake; the concentration of the oxalic acid is 10 mol/L; the high-purity water is the pure water with the conductivity less than or equal to 20 mu s/M and the resistivity more than or equal to 5M omega cm after the raw water is treated;
(3) and (3) drying the filter cake obtained in the step (2) at 60 ℃ for 9h, then crushing, burning at 850 ℃ for 2h, and naturally cooling to room temperature to obtain the ultrafine dysprosium oxide.
According to the method for preparing the ultrafine dysprosium oxide, the average particle size D50 of the obtained ultrafine dysprosium oxide is 2.72 um.
Example 4:
a method for preparing ultra-fine dysprosium oxide comprises the following steps:
(1) stirring 7.5mol/L ammonia water for 5min, adding dysprosium chloride feed liquid at a constant speed, controlling the adding time to be 100min, controlling the molar ratio of dysprosium chloride to ammonia water to be 1:3.2, stirring for 10min at a speed of 500r/min after the feeding is finished, and adjusting the pH value to 7 by using the ammonia water to obtain a colloidal solution; the concentration of dysprosium chloride in the dysprosium chloride feed liquid is 0.795 mol/L;
(2) weighing an oxalic acid solution according to the weight ratio of dysprosium oxide to oxalic acid of 1:2.1, heating the oxalic acid solution to 80 ℃ under the stirring condition of 500r/min, preserving heat, then adding the oxalic acid solution into the colloidal solution obtained in the step (1) at a constant speed, controlling the adding time to be 40min, stirring the oxalic acid solution for 10min after the adding is finished, standing for clarification, filtering to obtain a precipitate, washing the precipitate with high-purity water for 3 times, then washing with ethanol, and performing suction filtration to obtain a filter cake; the concentration of the oxalic acid is 20 mol/L; the high-purity water is the pure water with the conductivity less than or equal to 20 mu s/M and the resistivity more than or equal to 5M omega cm after the raw water is treated;
(3) and (3) drying the filter cake obtained in the step (2) at 60 ℃ for 8-12 h, then crushing, burning at 850 ℃ for 2h, and naturally cooling to room temperature to obtain the ultrafine dysprosium oxide.
According to the method for preparing the ultrafine dysprosium oxide, the average particle size D50 of the obtained ultrafine dysprosium oxide is 2.66 um.
Example 5:
a method for preparing ultra-fine dysprosium oxide comprises the following steps:
(1) stirring ammonia water with the concentration of 15.0mol/L for 5min, then adding dysprosium chloride feed liquid at a constant speed, controlling the adding time to be 35min, controlling the molar ratio of dysprosium chloride to ammonia water to be 1:3, stirring for 10min under the condition that the speed is 600r/min after the feeding is finished, and simultaneously adjusting the pH value to be 6 by using the ammonia water to obtain a colloidal solution; the concentration of dysprosium chloride in the dysprosium chloride feed liquid is 1.597 mol/L;
(2) weighing an oxalic acid solution according to the weight ratio of dysprosium oxide to oxalic acid of 1:2.1, heating the oxalic acid solution to 70 ℃ under the stirring condition of the speed of 600r/min, preserving heat, then adding the oxalic acid solution into the colloidal solution obtained in the step (1) at a constant speed, controlling the adding time to be 50min, stirring the oxalic acid solution for 10min after the adding is finished, standing for clarification, filtering to obtain a precipitate, washing the precipitate with high-purity water for 2 times, then washing with ethanol, and performing suction filtration to obtain a filter cake; the concentration of the oxalic acid is 15 mol/L; the high-purity water is the pure water with the conductivity less than or equal to 20 mu s/M and the resistivity more than or equal to 5M omega cm after the raw water is treated;
(3) and (3) drying the filter cake obtained in the step (2) at 60 ℃ for 8-12 h, then crushing, burning at 850 ℃ for 2h, and naturally cooling to room temperature to obtain the ultrafine dysprosium oxide.
According to the method for preparing the ultrafine dysprosium oxide, the average particle size D50 of the obtained ultrafine dysprosium oxide is 2.85 um.
Example 6:
a method for preparing ultra-fine dysprosium oxide comprises the following steps:
(1) stirring 5.0mol/L ammonia water for 5min, adding dysprosium chloride feed liquid at a constant speed, controlling the adding time to be 25min, controlling the molar ratio of dysprosium chloride to ammonia water to be 1:3.5, stirring at a speed of 200r/min for 10min after the feeding is finished, and adjusting the pH value to 7 by using the ammonia water to obtain a colloidal solution; the concentration of dysprosium chloride in the dysprosium chloride feed liquid is 0.448 mol/L;
(2) weighing an oxalic acid solution according to the weight ratio of dysprosium oxide to oxalic acid of 1:1.7, heating the oxalic acid solution to 80 ℃ under the stirring condition of the speed of 200r/min, preserving heat, then adding the oxalic acid solution into the colloidal solution obtained in the step (1) at a constant speed, controlling the adding time to be 100min, stirring the oxalic acid solution for 10min after the adding is finished, standing for clarification, filtering to obtain a precipitate, washing the precipitate with high-purity water for 2 times, then washing with ethanol, and performing suction filtration to obtain a filter cake; the concentration of the oxalic acid is 20 mol/L; the high-purity water is the pure water with the conductivity less than or equal to 20 mu s/M and the resistivity more than or equal to 5M omega cm after the raw water is treated;
(3) and (3) drying the filter cake obtained in the step (2) at 60 ℃ for 8-12 h, then crushing, burning at 850 ℃ for 2h, and naturally cooling to room temperature to obtain the ultrafine dysprosium oxide.
According to the method for preparing the ultrafine dysprosium oxide, the average particle size D50 of the obtained ultrafine dysprosium oxide is 2.52 um.
Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.
Claims (8)
1. A method for preparing ultra-fine dysprosium oxide is characterized in that: the method comprises the following steps:
(1) stirring ammonia water for 5min, adding dysprosium chloride feed liquid, wherein the molar ratio of dysprosium chloride to ammonia water is 1 (3-4), stirring for 10min after feeding is finished, and adjusting the pH value to 6-7 by using ammonia water to obtain a colloidal solution;
(2) weighing an oxalic acid solution according to the weight ratio of dysprosium oxide to oxalic acid being 1 (1.7-2.1), heating the oxalic acid solution to 50-80 ℃ under the stirring condition, preserving heat, adding the oxalic acid solution into the colloidal solution obtained in the step (1), stirring for 10min after the oxalic acid solution is added, standing, clarifying, filtering to obtain a precipitate, washing the precipitate with high-purity water for 2-3 times, then washing with ethanol, and performing suction filtration to obtain a filter cake;
(3) and (3) drying the filter cake obtained in the step (2) at 60 ℃ for 8-12 h, then crushing, burning at 850 ℃ for 2h, and naturally cooling to room temperature to obtain the ultrafine dysprosium oxide.
2. The method for preparing ultra-fine dysprosium oxide as claimed in claim 1, wherein: the concentration of the ammonia water is 3.0-15.0 mol/L.
3. The method for preparing ultra-fine dysprosium oxide as claimed in claim 1, wherein: the concentration of dysprosium chloride in the dysprosium chloride feed liquid is 0.448-1.597 mol/L.
4. The method for preparing ultra-fine dysprosium oxide as claimed in claim 1, wherein: and (2) taking ammonia water in the step (1), stirring for 5min, then adding dysprosium chloride liquid at a constant speed, and controlling the adding time to be 25-100 min.
5. The method for preparing ultra-fine dysprosium oxide as claimed in claim 1, wherein: and (3) adding the oxalic acid solution into the colloidal solution at a constant speed in the step (2), wherein the adding time is controlled to be 20-100 min.
6. The method for preparing ultra-fine dysprosium oxide as claimed in claim 1, wherein: the concentration of the oxalic acid is 10-20 mol/L.
7. The method for preparing ultra-fine dysprosium oxide as claimed in claim 1, wherein: in the step (1), the stirring speed is 200-600 r/min.
8. The method for preparing ultra-fine dysprosium oxide as claimed in claim 1, wherein: in the step (2), the stirring speed is 200-600 r/min.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111533158A (en) * | 2020-04-24 | 2020-08-14 | 广西科学院 | Microwave calcination preparation method of dysprosium oxide nano powder |
| CN113023761A (en) * | 2021-04-14 | 2021-06-25 | 中稀(常州)稀土新材料有限公司 | Industrial processing technology for effectively improving mixing and clarifying effects of dysprosium oxide |
| CN115159557A (en) * | 2022-08-09 | 2022-10-11 | 赣州湛海新材料科技有限公司 | Preparation method of nano dysprosium oxide |
| CN117185336A (en) * | 2023-11-08 | 2023-12-08 | 中稀(江苏)稀土有限公司 | Controllable preparation method for superfine dysprosium oxide specific surface area |
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2019
- 2019-12-27 CN CN201911379825.8A patent/CN110980788A/en active Pending
Non-Patent Citations (1)
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| 陈其安等: ""细粒度氧化钇生产的新方法"", 《中国稀土学报》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111533158A (en) * | 2020-04-24 | 2020-08-14 | 广西科学院 | Microwave calcination preparation method of dysprosium oxide nano powder |
| CN113023761A (en) * | 2021-04-14 | 2021-06-25 | 中稀(常州)稀土新材料有限公司 | Industrial processing technology for effectively improving mixing and clarifying effects of dysprosium oxide |
| CN115159557A (en) * | 2022-08-09 | 2022-10-11 | 赣州湛海新材料科技有限公司 | Preparation method of nano dysprosium oxide |
| CN115159557B (en) * | 2022-08-09 | 2024-01-30 | 赣州湛海新材料科技有限公司 | Preparation method of nano dysprosium oxide |
| CN117185336A (en) * | 2023-11-08 | 2023-12-08 | 中稀(江苏)稀土有限公司 | Controllable preparation method for superfine dysprosium oxide specific surface area |
| CN117185336B (en) * | 2023-11-08 | 2024-01-16 | 中稀(江苏)稀土有限公司 | Controllable preparation method for superfine dysprosium oxide specific surface area |
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Application publication date: 20200410 |