High-activity magnesium oxide and preparation method thereof
Highly active magnesium oxide was prepared by wet ball milling, spray drying and calcination, which solved the problem of insufficient activity in the existing technology, realized efficient and low-cost magnesium oxide production and improved the utilization rate of magnesite.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA ENFI ENG CORP
- Filing Date
- 2026-01-07
- Publication Date
- 2026-04-21
AI Technical Summary
Existing methods for preparing active magnesium oxide suffer from insufficient product activity, and traditional methods are costly, lengthy, and difficult to effectively utilize magnesite resources.
Highly active magnesium oxide is prepared by using lightly calcined magnesium oxide as raw material and through wet ball milling, spray drying and calcination processes, including wet ball milling with dispersant treatment, spray drying and calcination steps.
It significantly improves the activity of magnesium oxide, reduces production costs, increases the utilization rate of magnesite raw materials, and enables the efficient production of high-value-added products while being environmentally friendly and pollution-free.
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Figure CN121894686A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of chemical technology, and in particular to a highly active magnesium oxide and its preparation method. Background Technology
[0002] Compared with ordinary magnesium oxide, highly active magnesium oxide has different properties in terms of magnetism, optics, electricity, and heat, making it a new type of multifunctional material. Due to its high activity, high specific surface area, and high light transmittance, it is widely used in aerospace, rubber, electronics, defense, optics, instrumentation, and many other fields. In addition, highly active magnesium oxide has a strong adsorption capacity and can be used as an adsorbent to absorb toxic gases, protecting the environment. Furthermore, highly active magnesium oxide can also be used as a high-temperature and corrosion-resistant material, and in fine ceramic products.
[0003] Currently, the main methods for preparing active magnesium oxide include the brine-ammonium carbonate precipitation method, the calcination method, and the stepped calcination method. The brine-ammonium carbonate method uses brine as the magnesium source, reacting with ammonium carbonate to form a basic magnesium carbonate precursor, which is then calcined to decompose and obtain highly active magnesium oxide. This method suffers from a lengthy process and high cost. The calcination method uses high-quality magnesite as raw material, obtaining active magnesium oxide through physical impurity removal pretreatment and calcination. This process is simple and low-cost; however, with the continuous mining of magnesite, high-quality magnesite is decreasing year by year, and the amount of impurities in the mineral is increasing, making it difficult to obtain highly active magnesium oxide products using this method. The stepped calcination method uses a stepped heating and holding calcination process to calcine magnesite, which can shorten the magnesium oxide lattice transformation time and improve the activity of magnesium oxide to some extent, but the activity of the product obtained by this process still needs improvement. Summary of the Invention
[0004] To address the issue of insufficient activity in existing methods for preparing activated magnesium oxide, this invention provides a highly active magnesium oxide and its preparation method. This invention employs the following technical solution: This invention provides a method for preparing highly active magnesium oxide, comprising the following steps: Step 1) The lightly calcined magnesium oxide is subjected to wet ball milling to obtain magnesium oxide slurry; A dispersant is added during the wet ball milling process; Step 2) Spray dry the magnesium oxide slurry to obtain magnesium oxide powder; Step 3) The magnesium oxide powder is calcined to obtain the highly active magnesium oxide.
[0005] In an optional implementation, the mass fraction of magnesium oxide in the lightly calcined magnesium oxide in step one) is ≥80%.
[0006] In one optional implementation, the light-burned magnesium oxide in step one) is purchased from Haicheng Huanling Magnesium Products Manufacturing Co., Ltd., Dashiqiao Huayi Light-burned Magnesium Plant, or Dashiqiao Xinda Refractory Materials Co., Ltd.
[0007] In one alternative implementation, the liquid medium for the wet ball milling process in step one) includes water.
[0008] Optionally, the mass ratio of the lightly calcined magnesium oxide to the liquid medium is 1:(2-5). For example, the mass ratio of the lightly calcined magnesium oxide to the liquid medium can be any value among 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, 1:5, or any value within the range formed by any two of the above ratios.
[0009] In one optional embodiment, the dispersant includes at least one of sodium hexametaphosphate, water glass, and polyethylene glycol.
[0010] In one optional embodiment, the modulus of the water glass is 1-2, and the degree of polymerization of the polyethylene glycol is 300-500.
[0011] In an optional embodiment, the mass ratio of light-burned magnesium oxide to dispersant is 100:(0.5-5.0). Exemplarily, the mass ratio of light-burned magnesium oxide to dispersant can be any value from 100:0.5, 100:0.7, 100:1, 100:1.2, 100:1.5, 100:1.7, 100:2, 100:2.3, 100:2.5, 100:2.7, 100:3, 100:3.2, 100:3.5, 100:3.7, 100:4, 100:4.3, 100:4.5, 100:4.7, 100:5, or any value within the range formed by any two of the above ratios.
[0012] In one optional implementation, the wet ball milling process in step one) is selected from drum ball milling, vibratory ball milling, or planetary ball milling.
[0013] In an optional implementation, the wet ball milling process in step one) is performed at a rotation speed of 300 rpm to 1200 rpm, with a ball-to-material ratio of (5-15):1, and a time of 1 h to 4 h. For example, the rotation speed can be any value from 300 rpm, 400 rpm, 500 rpm, 600 rpm, 700 rpm, 800 rpm, 900 rpm, 1000 rpm, 1100 rpm, 1200 rpm, or any value within the range formed by any two of the above ratios; the ball-to-material ratio can be any value from 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, 11:1, 12:1, 13:1, 14:1, 15:1, or any value within the range formed by any two of the above ratios; and the time can be any value from 1 h, 1.5 h, 2 h, 2.5 h, 3 h, 3.5 h, 4 h, or any value within the range formed by any two of the above ratios.
[0014] In an optional embodiment, the spray drying process in step two) is carried out at a temperature of 200℃-400℃ and a flow rate of 500mL / min-1000mL / min. For example, the temperature can be any value from 200℃, 220℃, 230℃, 250℃, 280℃, 290℃, 300℃, 320℃, 340℃, 350℃, 370℃, 380℃, 400℃, or any value within the range formed by any two of the above ratios; the flow rate can be any value from 500 mL / min, 550 mL / min, 600 mL / min, 650 mL / min, 700 mL / min, 750 mL / min, 800 mL / min, 850 mL / min, 900 mL / min, 950 mL / min, 1000 mL / min, or any value within the range formed by any two of the above ratios.
[0015] In an optional embodiment, step two) further includes sieving the magnesium oxide slurry before spray drying, and adding water to the undersize material to adjust the slurry.
[0016] In one optional implementation, the sieve mesh size is ≥300 mesh.
[0017] In an optional embodiment, the solids content of the slurry obtained by mixing is 15 wt.%-40 wt.%. Exemplarily, the solids content can be any value from 15 wt.%, 17 wt.%, 19 wt.%, 20 wt.%, 22 wt.%, 24 wt.%, 25 wt.%, 27 wt.%, 29 wt.%, 30 wt.%, 31 wt.%, 33 wt.%, 35 wt.%, 37 wt.%, 38 wt.%, 40 wt.%, or any value within a range formed by any two of the above ratios.
[0018] The solid content of a slurry refers to the mass fraction of solid substances in the slurry.
[0019] In an optional embodiment, the calcination treatment in step three) is carried out at a temperature of 400℃-800℃ for a time of 1h-4h. For example, the calcination temperature can be any value from 400℃, 430℃, 450℃, 480℃, 500℃, 520℃, 550℃, 600℃, 630℃, 650℃, 670℃, 700℃, 730℃, 750℃, 770℃, 800℃, or any value within the range formed by any two of the above ratios; the time can be any value from 1h, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, or any value within the range formed by any two of the above ratios.
[0020] The present invention also provides highly active magnesium oxide prepared by the above-mentioned method for preparing highly active magnesium oxide.
[0021] Optionally, the highly active magnesium oxide has an iodine uptake value ≥130 mg / g.
[0022] The beneficial effects of this invention are as follows: 1. This invention provides a method for preparing highly active magnesium oxide, comprising the following steps: Step 1) Wet ball milling of lightly calcined magnesium oxide to obtain magnesium oxide slurry; adding a dispersant during the wet ball milling process; Step 2) Spray drying of the magnesium oxide slurry to obtain magnesium oxide powder; Step 3) Calcination of the magnesium oxide powder to obtain highly active magnesium oxide.
[0023] This invention uses lightly calcined magnesia powder as raw material and employs wet ball milling, spray drying, and calcination processes to successfully produce a highly active magnesia product. Lightly calcined magnesia is a low-value-added product obtained from the calcination of magnesite raw materials. This invention uses lightly calcined magnesia as raw material to transform it into highly active magnesia, effectively improving the utilization rate of magnesite raw materials and realizing the effective transformation of inexpensive products into high-value-added products.
[0024] Among them, wet ball milling refines the particle size of lightly calcined magnesium oxide powder through mechanical grinding, increases its specific surface area, and significantly improves the activity of magnesium oxide; at the same time, the addition of dispersant during wet ball milling can significantly reduce the agglomeration of particles caused by van der Waals forces; spray drying rapidly dries the slurry obtained by slurry preparation, maintains the particle dispersion state, and ensures the homogeneity of subsequent calcination; finally, a high-activity product with an iodine uptake value ≥130mg / g is obtained through calcination.
[0025] 2. The preparation method of this invention has a short process, high production efficiency, low production cost, and the obtained product has high activity. Furthermore, the entire preparation process of this invention does not use acid or alkali reagents, and no waste liquid or residue is generated during the reaction, thus causing no environmental pollution. Attached Figure Description
[0026] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0027] Figure 1 This is a flowchart illustrating the preparation process of highly active magnesium oxide in this invention. Detailed Implementation
[0028] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention. It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the present invention.
[0029] Furthermore, regarding the numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, are also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.
[0030] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.
[0031] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention.
[0032] In the following embodiments and comparative examples of the present invention, the light-burned magnesium oxide was purchased from Huayi Light-burned Magnesium Plant in Dashiqiao City.
[0033] In the following embodiments and comparative examples of the present invention, the test of active iodine uptake value was carried out in accordance with the HG / T 3928-2012 industrial active magnesium oxide test standard.
[0034] Example 1 This embodiment provides a method for preparing highly active magnesium oxide, the process of which is as follows: Figure 1 As shown, it includes the following steps: Lightly calcined magnesia (with a magnesium oxide mass fraction of 85%) was taken. Deionized water was added at a mass ratio of 1:4 for lightly calcined magnesia to deionized water, and sodium hexametaphosphate was added at a mass ratio of 100:2.5 for lightly calcined magnesia to sodium hexametaphosphate. After mixing evenly, the mixture was placed in a planetary ball mill jar and wet-milled at a ball-to-material ratio of 10:1 and a speed of 800 rpm for 2 hours. After the wet-milling, the magnesia slurry was passed through a 300-mesh sieve to obtain the undersize material. Water was added to the undersize material to prepare a slurry with a solid content of 20 wt.%. The slurry was then spray-dried at a flow rate of 800 mL / min and a temperature of 300 °C to obtain magnesia powder. The magnesia powder was then calcined at 600 °C for 2 hours to obtain highly active magnesia.
[0035] The test results showed that the iodine uptake value of the highly active magnesium oxide obtained in this embodiment was 140 mg / g. The calculated recovery rate of the highly active magnesium oxide (the percentage of highly active magnesium oxide by mass of MgO in the raw material (lightly calcined magnesium oxide)) was 82%.
[0036] Example 2 This embodiment provides a method for preparing highly active magnesium oxide, including the following steps: Lightly calcined magnesium oxide (with a magnesium oxide mass fraction of 80%) was taken and added to deionized water at a mass ratio of 1:2. Polyethylene glycol (PEG) was added at a mass ratio of 100:0.5 to calcined magnesium oxide (with a degree of polymerization of 300). After thorough mixing, the mixture was placed in a drum-type ball mill and wet-milled at a ball-to-material ratio of 15:1 and a speed of 300 rpm for 3 hours. After the milling process, the magnesium oxide slurry was passed through a 325-mesh sieve to obtain the undersize material. Water was added to the undersize material to prepare a slurry with a solid content of 40 wt.%. The slurry was then spray-dried at a flow rate of 1000 mL / min and a temperature of 400℃ to obtain magnesium oxide powder. The magnesium oxide powder was then calcined at 800℃ for 1 hour to obtain highly active magnesium oxide.
[0037] The test results showed that the iodine uptake value of the highly active magnesium oxide obtained in this embodiment was 150 mg / g. The recovery rate of the highly active magnesium oxide was calculated to be 81%.
[0038] Example 3 This embodiment provides a method for preparing highly active magnesium oxide, including the following steps: Lightly calcined magnesia (90% by mass) was taken and added to deionized water at a mass ratio of 1:5, and to water glass (modulus 1.5) at a mass ratio of 100:5. After mixing evenly, the mixture was placed in a vibrating ball mill jar and wet-milled at a ball-to-material ratio of 8:1 and a speed of 600 rpm for 4 hours. After the process, the magnesia slurry was passed through a 350-mesh sieve to obtain the undersize material. Water was added to the undersize material to prepare a slurry with a solid content of 15 wt.%. The slurry was then spray-dried at a flow rate of 500 mL / min and a temperature of 200 °C to obtain magnesia powder. The magnesia powder was then calcined at 400 °C for 3 hours to obtain highly active magnesia.
[0039] The test results showed that the iodine uptake value of the highly active magnesium oxide obtained in this embodiment was 160 mg / g. The recovery rate of the highly active magnesium oxide was calculated to be 86%.
[0040] Example 4 This embodiment provides a method for preparing highly active magnesium oxide, including the following steps: Lightly calcined magnesia (with a magnesia mass fraction of 85%) was taken. Deionized water was added at a mass ratio of 1:3 for lightly calcined magnesia to deionized water, and water glass (modulus 1) was added at a mass ratio of 100:3 for lightly calcined magnesia to water glass. After mixing evenly, the mixture was placed in a planetary ball mill jar and wet-milled at a ball-to-material ratio of 5:1 and a speed of 1200 rpm for 1 hour. After the wet-milling process, the magnesia slurry was passed through a 300-mesh sieve to obtain the undersize material. Water was added to the undersize material to prepare a slurry with a solid content of 25 wt.%. The slurry was then spray-dried at a flow rate of 600 mL / min and a temperature of 300 °C to obtain magnesia powder. The magnesia powder was then calcined at 550 °C for 2 hours to obtain highly active magnesia.
[0041] The tests showed that the highly active magnesium oxide obtained in this embodiment had an iodine uptake value of 180 mg / g. The recovery rate of the highly active magnesium oxide was calculated to be 84%.
[0042] Example 5 This embodiment provides a method for preparing highly active magnesium oxide, including the following steps: Lightly calcined magnesia (magnesia mass fraction of 85%) was taken, and deionized water was added at a mass ratio of 1:2. Sodium hexametaphosphate was added at a mass ratio of 100:1. After mixing evenly, the mixture was placed in a planetary ball mill jar and wet-milled at a ball-to-material ratio of 10:1 and a speed of 800 rpm for 2 hours. After the wet-milling, the magnesia slurry was passed through a 300-mesh sieve to obtain the undersize material. Water was added to the undersize material to make a slurry with a solid content of 20 wt.%. The slurry was then spray-dried at a flow rate of 800 mL / min and a temperature of 300℃ to obtain magnesia powder. The magnesia powder was then calcined at 600℃ for 2 hours to obtain highly active magnesia.
[0043] The test results showed that the iodine uptake value of the highly active magnesium oxide obtained in this embodiment was 130 mg / g. The recovery rate of the highly active magnesium oxide was calculated to be 81%.
[0044] Example 6 This embodiment provides a method for preparing highly active magnesium oxide, including the following steps: Lightly calcined magnesia (with a magnesia mass fraction of 85%) was taken. Deionized water was added at a mass ratio of 1:3 for lightly calcined magnesia to deionized water, and sodium hexametaphosphate was added at a mass ratio of 100:4 for lightly calcined magnesia to sodium hexametaphosphate. After mixing evenly, the mixture was placed in a planetary ball mill jar and wet-milled at a ball-to-material ratio of 10:1 and a speed of 800 rpm for 2 hours. After the wet-milling process, the magnesia slurry was passed through a 300-mesh sieve to obtain the undersize material. Water was added to the undersize material to prepare a slurry with a solid content of 20 wt.%. The slurry was then spray-dried at a flow rate of 800 mL / min and a temperature of 300 °C to obtain magnesia powder. The magnesia powder was then calcined at 600 °C for 2 hours to obtain highly active magnesia.
[0045] The test results showed that the iodine uptake value of the highly active magnesium oxide obtained in this embodiment was 135 mg / g. The recovery rate of the highly active magnesium oxide was calculated to be 82%.
[0046] Example 7 This embodiment provides a method for preparing highly active magnesium oxide, including the following steps: Lightly calcined magnesium oxide (with a magnesium oxide mass fraction of 85%) was taken and added to deionized water at a mass ratio of 1:3. Polyethylene glycol (with a degree of polymerization of 500) was added at a mass ratio of 100:4. After thorough mixing, the mixture was placed in a planetary ball mill jar and wet-milled at a ball-to-material ratio of 10:1 and a speed of 800 rpm for 2 hours. After the milling process, the magnesium oxide slurry was passed through a 300-mesh sieve to obtain the undersize material. Water was added to the undersize material to prepare a slurry with a solid content of 20 wt.%. The slurry was then spray-dried at a flow rate of 800 mL / min and a temperature of 300°C to obtain magnesium oxide powder. The magnesium oxide powder was then calcined at 600°C for 2 hours to obtain highly active magnesium oxide.
[0047] The test results showed that the iodine uptake value of the highly active magnesium oxide obtained in this embodiment was 145 mg / g. The recovery rate of the highly active magnesium oxide was calculated to be 82%.
[0048] Example 8 This embodiment provides a method for preparing highly active magnesium oxide, including the following steps: Lightly calcined magnesium oxide (with a magnesium oxide mass fraction of 85%) was taken and added to deionized water at a mass ratio of 1:4. Polyethylene glycol (PEG) was added at a mass ratio of 100:5 to MgO (degree of polymerization 400). After thorough mixing, the mixture was placed in a planetary ball mill jar and wet-milled at a ball-to-material ratio of 10:1 and a speed of 800 rpm for 2 hours. After the milling process, the magnesium oxide slurry was passed through a 300-mesh sieve to obtain the undersize material. Water was added to the undersize material to prepare a slurry with a solid content of 20 wt.%. The slurry was then spray-dried at a flow rate of 800 mL / min and a temperature of 300 °C to obtain magnesium oxide powder. The magnesium oxide powder was then calcined at 600 °C for 2 hours to obtain highly active magnesium oxide.
[0049] The test results showed that the iodine uptake value of the highly active magnesium oxide obtained in this embodiment was 148 mg / g. The recovery rate of the highly active magnesium oxide was calculated to be 81%.
[0050] Example 9 This embodiment provides a method for preparing highly active magnesium oxide, including the following steps: Lightly calcined magnesia (with a magnesia mass fraction of 85%) was taken. Deionized water was added at a mass ratio of 1:2 for lightly calcined magnesia to deionized water, and water glass (modulus 2) was added at a mass ratio of 100:1 for lightly calcined magnesia to water glass. After mixing evenly, the mixture was placed in a planetary ball mill jar and wet-milled at a ball-to-material ratio of 10:1 and a speed of 800 rpm for 2 hours. After the wet-milling process, the magnesia slurry was passed through a 300-mesh sieve to obtain the undersize material. Water was added to the undersize material to prepare a slurry with a solid content of 20 wt.%. The slurry was then spray-dried at a flow rate of 800 mL / min and a temperature of 300 °C to obtain magnesia powder. The magnesia powder was then calcined at 600 °C for 2 hours to obtain highly active magnesia.
[0051] The test results showed that the iodine uptake value of the highly active magnesium oxide obtained in this embodiment was 150 mg / g. The recovery rate of the highly active magnesium oxide was calculated to be 83%.
[0052] Comparative Example 1 This comparative example provides a method for preparing active magnesium oxide. Compared with Example 1, this comparative example does not perform wet ball milling treatment on lightly calcined magnesium oxide, and specifically includes the following steps: Lightly calcined magnesium oxide (with a magnesium oxide mass fraction of 85%) was passed through a 300-mesh sieve to obtain undersize material. Water was added to the undersize material to make a slurry with a solid content of 20 wt.%. The slurry was then spray-dried at a flow rate of 800 mL / min and a temperature of 300 °C to obtain magnesium oxide powder. The magnesium oxide powder was then calcined at 600 °C for 2 hours to obtain active magnesium oxide.
[0053] The test results showed that the active iodine uptake value of the active magnesium oxide obtained in this comparative example was 29 mg / g. The calculated recovery rate of the active magnesium oxide was 65%.
[0054] Comparative Example 2 This comparative example provides a method for preparing active magnesium oxide. Compared with Example 1, the addition of sodium hexametaphosphate in Example 1 is omitted, and the method specifically includes the following steps: Lightly calcined magnesia (magnesia mass fraction of 85%) was taken and added to deionized water at a mass ratio of 1:4. After mixing evenly, the mixture was placed in a planetary ball mill jar and wet-milled at a ball-to-material ratio of 10:1 and a speed of 800 rpm for 2 hours. After the wet-milling process, the magnesia slurry was passed through a 300-mesh sieve to obtain the undersize material. Water was added to the undersize material to prepare a slurry with a solid content of 20 wt.%. The slurry was then spray-dried at a flow rate of 800 mL / min and a temperature of 300℃ to obtain magnesia powder. The magnesia powder was then calcined at 600℃ for 2 hours to obtain highly active magnesia.
[0055] The test results showed that the active iodine uptake value of the active magnesium oxide obtained in this comparative example was 35 mg / g. The calculated recovery rate of the active magnesium oxide was 58%.
[0056] Comparative Example 3 This comparative example provides a method for preparing active magnesium oxide, comprising the following steps: Magnesite is taken, crushed, and then roasted at 800℃ for 2 hours. After roasting, it is passed through a 300-mesh sieve, and the material passing through the sieve is active magnesium oxide.
[0057] The test results showed that the active iodine uptake value of the active magnesium oxide obtained in this comparative example was 43 mg / g. The calculated recovery rate of the active magnesium oxide was 53%.
[0058] Comparative Example 4 This comparative example provides a method for preparing active magnesium oxide, comprising the following steps: Magnesite is taken, crushed, and then roasted. It is first roasted at 650℃ for 2 hours, and then the temperature is raised to 700℃ for 1 hour. After roasting, it is passed through a 300-mesh sieve. The material passing through the sieve is active magnesium oxide.
[0059] The test results showed that the active iodine uptake value of the active magnesium oxide obtained in this comparative example was 95 mg / g. The calculated recovery rate of the active magnesium oxide was 74%.
[0060] As can be seen from the comparison of the examples and comparative examples, the active iodine uptake value of the active magnesium oxide prepared by the method of this application is significantly improved, all exceeding 130 mg / g. Furthermore, the recovery rate of the highly active magnesium oxide prepared by the method of this application is also significantly improved, resulting in high production efficiency.
[0061] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.
Claims
1. A method for preparing highly active magnesium oxide, characterized in that, Includes the following steps: Step 1) The lightly calcined magnesium oxide is subjected to wet ball milling to obtain magnesium oxide slurry; A dispersant is added during the wet ball milling process; Step 2) Spray dry the magnesium oxide slurry to obtain magnesium oxide powder; Step 3) The magnesium oxide powder is calcined to obtain the highly active magnesium oxide.
2. The method for preparing highly active magnesium oxide according to claim 1, characterized in that, Step 1) The mass fraction of magnesium oxide in the lightly calcined magnesium oxide is ≥80%.
3. The method for preparing highly active magnesium oxide according to claim 1, characterized in that, Step 1) The liquid medium used in the wet ball milling process includes water; Optionally, the mass ratio of the lightly calcined magnesium oxide to the liquid medium is 1:(2-5).
4. The method for preparing highly active magnesium oxide according to claim 1, characterized in that, The dispersant includes at least one of sodium hexametaphosphate, water glass, and polyethylene glycol; Optionally, the modulus of the water glass is 1-2; Optionally, the degree of polymerization of the polyethylene glycol is 300-500.
5. The method for preparing highly active magnesium oxide according to claim 4, characterized in that, The mass ratio of the lightly calcined magnesium oxide to the dispersant is 100:(0.5-5.0).
6. The method for preparing highly active magnesium oxide according to claim 1, characterized in that, Step 1) The wet ball milling process is carried out at a speed of 300 rpm to 1200 rpm, a ball-to-material ratio of (5-15):1, and a time of 1 h to 4 h.
7. The method for preparing highly active magnesium oxide according to claim 1, characterized in that, Step 2) The spray drying process is carried out at a temperature of 200℃-400℃ and a flow rate of 500mL / min-1000mL / min.
8. The method for preparing highly active magnesium oxide according to claim 1, characterized in that, Step 2) Before spray drying the magnesium oxide slurry, the magnesium oxide slurry is also screened, and water is added to the undersize material to adjust the slurry. Optionally, the sieve mesh size is ≥300 mesh; And / or, the solid content of the slurry obtained by slurry preparation is 15wt.%-40wt.%.
9. The method for preparing highly active magnesium oxide according to claim 1, characterized in that, Step 3) The roasting treatment is carried out at a temperature of 400℃-800℃ for 1h-4h.
10. A highly active magnesium oxide, characterized in that, The highly active magnesium oxide is prepared by the method according to any one of claims 1-9.