CN113174147A - Submicron spherical zinc oxide particle and preparation method thereof - Google Patents
Submicron spherical zinc oxide particle and preparation method thereof Download PDFInfo
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- CN113174147A CN113174147A CN202110390657.3A CN202110390657A CN113174147A CN 113174147 A CN113174147 A CN 113174147A CN 202110390657 A CN202110390657 A CN 202110390657A CN 113174147 A CN113174147 A CN 113174147A
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
- C09C1/00—Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
- C09C1/04—Compounds of zinc
- C09C1/043—Zinc oxide
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
- C09C3/00—Treatment in general of inorganic materials, other than fibrous fillers, to enhance their pigmenting or filling properties
- C09C3/04—Physical treatment, e.g. grinding, treatment with ultrasonic vibrations
- C09C3/041—Grinding
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/01—Particle morphology depicted by an image
- C01P2004/03—Particle morphology depicted by an image obtained by SEM
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/30—Particle morphology extending in three dimensions
- C01P2004/32—Spheres
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
Abstract
The invention discloses a submicron spherical zinc oxide particle and a preparation method thereof. The preparation method of the submicron spherical-like zinc oxide particles comprises the following steps: 1) dispersing zinc oxide particles in an acidic solution or an alkaline solution to obtain slurry; 2) adding the slurry into a stirring mill, adding a grinding medium with the diameter of 0.1-1 mm, controlling the volume percentage of the grinding medium to be 60-85%, grinding, and drying to obtain the submicron spherical zinc oxide particles. The submicron-grade spherical zinc oxide particles are prepared by chemical corrosion-assisted wet superfine grinding, and the method has the advantages of simple preparation process, short preparation time, low cost, suitability for mass production and the like, and the obtained zinc oxide particles have high sphericity, fine granularity, narrow granularity distribution and high dispersion stability.
Description
Technical Field
The invention relates to the technical field of material processing, in particular to submicron spherical zinc oxide particles and a preparation method thereof.
Background
Submicron zinc oxide and nanometer zinc oxide have unique electrical, optical and thermal properties, and have been widely used in the fields of electronics, biomedicine, paint, filler, catalyst, cosmetics, etc. Besides the fineness, the appearance of the zinc oxide particles also has obvious influence on the application performance, wherein the zinc oxide particles with uniform particle size distribution and regular appearance (such as spherical or spheroidal) have the advantages of good fluidity, higher bulk density, larger specific surface area, lower thermal expansion coefficient and the like, and are beneficial to improving the product performance when in application.
At present, the methods for preparing ultrafine spherical or spheroidal zinc oxide particles are generally sol-gel methods, homogeneous precipitation methods, dropping ball methods, template methods and spraying methods, and the methods have the problems of complex process, high cost, low production efficiency and the like, and are difficult to popularize and apply in a large area. In addition, the mechanical grinding method is also a common method for preparing zinc oxide particles, but the shape of the superfine zinc oxide particles prepared by adopting a single mechanical grinding method is irregular, and the particle size distribution is not uniform.
Disclosure of Invention
The invention aims to provide submicron spherical zinc oxide particles and a preparation method thereof.
The technical scheme adopted by the invention is as follows:
a preparation method of submicron spherical zinc oxide particles comprises the following steps:
1) dispersing zinc oxide particles in an acidic solution or an alkaline solution to obtain slurry;
2) adding the slurry into a stirring mill, adding a grinding medium with the diameter of 0.1-1 mm, controlling the volume percentage of the grinding medium to be 60-85%, grinding, and drying to obtain the submicron spherical zinc oxide particles.
Preferably, the acidic solution in step 1) is at least one of a hydrochloric acid solution, a sulfuric acid solution, a citric acid solution, an oxalic acid solution and an acetic acid solution.
Preferably, the concentration of the acidic solution in the step 1) is 0.005mol/L to 0.1 mol/L.
Preferably, the alkaline solution in step 1) is at least one of a sodium hydroxide solution, ammonia water and an ammonium chloride solution.
Preferably, the concentration of the alkaline solution in the step 1) is 0.005 mol/L-0.1 mol/L.
Preferably, the solid content of the slurry in the step 1) is 10-50%.
Preferably, the grinding medium in step 2) is yttrium-stabilized zirconia beads.
Preferably, the grinding in the step 2) is carried out at a stirring and grinding rotating speed of 1000 r/min-2000 r/min, and the grinding time is 15 min-60 min.
Preferably, the drying in the step 2) is carried out at 60-100 ℃, and the drying time is 8-16 h.
Submicron spherical-like zinc oxide particles prepared by the above method.
The invention has the beneficial effects that: the submicron-grade spherical zinc oxide particles are prepared by chemical corrosion-assisted wet superfine grinding, and the method has the advantages of simple preparation process, short preparation time, low cost, suitability for mass production and the like, and the obtained zinc oxide particles have high sphericity, fine granularity, narrow granularity distribution and high dispersion stability.
Specifically, the method comprises the following steps:
1) the submicron-size-fraction spheroidal zinc oxide particles are prepared by chemical-etching-assisted wet-process superfine grinding, and compared with zinc oxide particles obtained without chemical etching assistance, the sphericity of the zinc oxide particles is remarkably improved, the particle size of the particles is smaller, and the particle size distribution is narrower;
2) the method has the advantages of simple process flow, short grinding time, low energy consumption, no waste discharge and high yield, and is suitable for industrial production;
3) the sphericity of the submicron spherical zinc oxide particles prepared by the invention reaches 0.91, the particle size of the particles is 0.1-0.8 mu m, and the submicron spherical zinc oxide particles are spherical zinc oxide particles with high sphericity and smaller particle size and can be widely applied to actual production.
Drawings
FIG. 1 is a graph showing the particle size distribution of submicron-sized spherical-like zinc oxide particles of example 1, micron-sized random-morphology zinc oxide particles of comparative example 1, and submicron-sized spherical-like zinc oxide particles of comparative example 2.
FIG. 2 is an SEM image of submicron spheroidal zinc oxide particles of example 1.
Fig. 3 is an SEM image of the micron-sized random morphology zinc oxide particles of comparative example 1.
Fig. 4 is an SEM image of the submicron-sized spheroidal zinc oxide particles of comparative example 2.
Detailed Description
The invention will be further explained and illustrated with reference to specific examples.
Example 1:
a submicron spherical-like zinc oxide particle is prepared by the following steps:
1) adding 20g of micron-grade zinc oxide particles with irregular morphology (the sphericity is 0.74, the particle size of 95 wt% of the zinc oxide particles is less than 5 mu m) into 80mL of acetic acid solution with the concentration of 0.01mol/L, and uniformly stirring to obtain slurry;
2) adding the slurry into a vertical stirring mill, adding yttrium-stabilized zirconia grinding beads with the diameter of 0.6mm, controlling the volume percentage of the yttrium-stabilized zirconia grinding beads to be 80%, adjusting the rotating speed of the vertical stirring mill to 1000r/min, grinding for 30min, transferring the material into an evaporation pan, placing the evaporation pan in a constant-temperature oven, and drying at 80 ℃ for 10h to obtain the submicron spherical zinc oxide particles.
Example 2:
a submicron spherical-like zinc oxide particle is prepared by the following steps:
1) adding 30g of micron-grade zinc oxide particles with irregular morphology (the sphericity is 0.74, and the particle size of 95 wt% of the zinc oxide particles is less than 5 mu m) into 70mL of hydrochloric acid solution with the concentration of 0.05mol/L, and uniformly stirring to obtain slurry;
2) adding the slurry into a vertical stirring mill, adding yttrium-stabilized zirconia grinding beads with the diameter of 1mm, controlling the volume percentage of the yttrium-stabilized zirconia grinding beads to be 75%, adjusting the rotating speed of the vertical stirring mill to 1500r/min, grinding for 20min, transferring the material into an evaporation pan, placing the evaporation pan in a constant-temperature oven, and drying at 80 ℃ for 10h to obtain submicron spherical-like zinc oxide particles.
Example 3:
a submicron spherical-like zinc oxide particle is prepared by the following steps:
1) adding 40g of micron-grade zinc oxide particles with irregular morphology (the sphericity is 0.74, the particle size of 95 wt% of the zinc oxide particles is less than 5 mu m) into 60mL of citric acid solution with the concentration of 0.1mol/L, and uniformly stirring to obtain slurry;
2) adding the slurry into a vertical stirring mill, adding yttrium-stabilized zirconia grinding beads with the diameter of 0.6mm, controlling the volume percentage of the yttrium-stabilized zirconia grinding beads to be 70%, adjusting the rotating speed of the vertical stirring mill to 2000r/min, grinding for 40min, transferring the material into an evaporation pan, placing the evaporation pan in a constant-temperature oven, and drying at 80 ℃ for 10h to obtain the submicron spherical zinc oxide particles.
Comparative example 1:
micron-sized zinc oxide particles with irregular morphology (the sphericity is 0.74, and the particle size of 95 wt% of the zinc oxide particles is less than 5 μm). Comparative example 2:
a submicron spherical-like zinc oxide particle is prepared by the following steps:
1) adding 20g of micron-grade zinc oxide particles with irregular morphology (the sphericity is 0.74, and the particle size of 95 wt% of the zinc oxide particles is less than 5 microns) into 80mL of deionized water, and uniformly stirring to obtain slurry;
2) adding the slurry into a vertical stirring mill, adding yttrium-stabilized zirconia grinding beads with the diameter of 0.6mm, controlling the volume percentage of the yttrium-stabilized zirconia grinding beads to be 80%, adjusting the rotating speed of the vertical stirring mill to 1000r/min, grinding for 30min, transferring the material into an evaporation pan, placing the evaporation pan in a constant-temperature oven, and drying at 80 ℃ for 10h to obtain the submicron spherical zinc oxide particles.
And (3) performance testing:
the particle size distribution diagrams of the submicron order spherical zinc oxide particles of example 1, the micron order irregular morphology zinc oxide particles of comparative example 1, and the submicron order spherical zinc oxide particles of comparative example 2 are shown in fig. 1 (a in the figure is interval distribution, b is cumulative distribution), the Scanning Electron Microscope (SEM) diagram of the submicron order spherical zinc oxide particles of example 1 is shown in fig. 2, the scanning electron microscope diagram of the micron order irregular morphology zinc oxide particles of comparative example 1 is shown in fig. 3, and the scanning electron microscope diagram of the submicron order spherical zinc oxide particles of comparative example 2 is shown in fig. 4.
As can be seen from FIGS. 1 to 4: after the zinc oxide particles with the micron-size level irregular morphology are ground for 30min only by a vertical stirring mill, the sphericity of the zinc oxide particles is only improved from 0.74 to 0.78, and the particle size is reduced, but after the zinc oxide particles are ground by the chemical corrosion-assisted wet-method superfine machine, the sphericity of the zinc oxide particles is as high as 0.91, the particle size is 0.1-0.8 mu m, the sphericity of the particles is high, the particle size is smaller, and the particle size distribution is narrower.
In addition, the submicron-sized spherical zinc oxide particles prepared in examples 2 and 3 were found to have a sphericity, a particle size range, and a particle size distribution very close to those of the submicron-sized spherical zinc oxide particles prepared in example 1.
The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.
Claims (10)
1. A method for preparing submicron spherical zinc oxide particles is characterized by comprising the following steps:
1) dispersing zinc oxide particles in an acidic solution or an alkaline solution to obtain slurry;
2) adding the slurry into a stirring mill, adding a grinding medium with the diameter of 0.1-1 mm, controlling the volume percentage of the grinding medium to be 60-85%, grinding, and drying to obtain the submicron spherical zinc oxide particles.
2. The method for producing submicron spherical-like zinc oxide particles according to claim 1, characterized in that: the acid solution in the step 1) is at least one of hydrochloric acid solution, sulfuric acid solution, citric acid solution, oxalic acid solution and acetic acid solution.
3. The method for producing submicron spherical-like zinc oxide particles according to claim 2, characterized in that: the concentration of the acid solution in the step 1) is 0.005 mol/L-0.1 mol/L.
4. The method for producing submicron spherical-like zinc oxide particles according to claim 1, characterized in that: the alkaline solution in the step 1) is at least one of a sodium hydroxide solution, ammonia water and an ammonium chloride solution.
5. The method for producing submicron spherical-like zinc oxide particles according to claim 4, wherein: the concentration of the alkaline solution in the step 1) is 0.005 mol/L-0.1 mol/L.
6. The method for producing submicron spherical-like zinc oxide particles according to any one of claims 1 to 5, characterized in that: the solid content of the slurry in the step 1) is 10-50%.
7. The method for producing submicron spherical-like zinc oxide particles according to any one of claims 1 to 5, characterized in that: and 2) grinding media are yttrium-stabilized zirconia grinding beads.
8. The method for producing submicron spherical-like zinc oxide particles according to any one of claims 1 to 5, characterized in that: and 2) grinding is carried out at the stirring and grinding rotating speed of 1000 r/min-2000 r/min for 15 min-60 min.
9. The method for producing submicron spherical-like zinc oxide particles according to any one of claims 1 to 5, characterized in that: the drying in the step 2) is carried out at the temperature of 60-100 ℃, and the drying time is 8-16 h.
10. Submicron spherical-like zinc oxide particles produced by the method according to any one of claims 1 to 9.
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