CN115057469B - Spherical calcium titanate preparation method - Google Patents
Spherical calcium titanate preparation method Download PDFInfo
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- CN115057469B CN115057469B CN202210735668.5A CN202210735668A CN115057469B CN 115057469 B CN115057469 B CN 115057469B CN 202210735668 A CN202210735668 A CN 202210735668A CN 115057469 B CN115057469 B CN 115057469B
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- calcium titanate
- spheroidization
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- AOWKSNWVBZGMTJ-UHFFFAOYSA-N calcium titanate Chemical compound [Ca+2].[O-][Ti]([O-])=O AOWKSNWVBZGMTJ-UHFFFAOYSA-N 0.000 title claims abstract description 59
- 238000002360 preparation method Methods 0.000 title claims abstract description 11
- 230000001788 irregular Effects 0.000 claims abstract description 26
- 238000000034 method Methods 0.000 claims abstract description 15
- 230000004048 modification Effects 0.000 claims abstract description 13
- 238000012986 modification Methods 0.000 claims abstract description 13
- 239000002994 raw material Substances 0.000 claims abstract description 9
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 8
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims abstract description 8
- 239000001301 oxygen Substances 0.000 claims abstract description 8
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 8
- 238000005054 agglomeration Methods 0.000 claims abstract description 6
- 230000002776 aggregation Effects 0.000 claims abstract description 5
- 239000012159 carrier gas Substances 0.000 claims abstract description 4
- 239000003345 natural gas Substances 0.000 claims abstract description 4
- 239000000843 powder Substances 0.000 claims abstract description 4
- 239000006087 Silane Coupling Agent Substances 0.000 claims description 7
- NKSJNEHGWDZZQF-UHFFFAOYSA-N ethenyl(trimethoxy)silane Chemical compound CO[Si](OC)(OC)C=C NKSJNEHGWDZZQF-UHFFFAOYSA-N 0.000 claims description 4
- FFUAGWLWBBFQJT-UHFFFAOYSA-N hexamethyldisilazane Chemical compound C[Si](C)(C)N[Si](C)(C)C FFUAGWLWBBFQJT-UHFFFAOYSA-N 0.000 claims description 4
- GJWAPAVRQYYSTK-UHFFFAOYSA-N [(dimethyl-$l^{3}-silanyl)amino]-dimethylsilicon Chemical compound C[Si](C)N[Si](C)C GJWAPAVRQYYSTK-UHFFFAOYSA-N 0.000 claims description 2
- 150000001343 alkyl silanes Chemical class 0.000 claims description 2
- FWDBOZPQNFPOLF-UHFFFAOYSA-N ethenyl(triethoxy)silane Chemical compound CCO[Si](OCC)(OCC)C=C FWDBOZPQNFPOLF-UHFFFAOYSA-N 0.000 claims description 2
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 abstract description 2
- 239000000945 filler Substances 0.000 abstract description 2
- 229910000077 silane Inorganic materials 0.000 abstract description 2
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 abstract 1
- 229910052791 calcium Inorganic materials 0.000 abstract 1
- 239000011575 calcium Substances 0.000 abstract 1
- 238000002485 combustion reaction Methods 0.000 abstract 1
- 239000007822 coupling agent Substances 0.000 abstract 1
- 230000000052 comparative effect Effects 0.000 description 15
- 239000002245 particle Substances 0.000 description 10
- 239000000047 product Substances 0.000 description 6
- 230000008569 process Effects 0.000 description 5
- 239000012467 final product Substances 0.000 description 3
- 239000000758 substrate Substances 0.000 description 3
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000002105 nanoparticle Substances 0.000 description 2
- 102220043159 rs587780996 Human genes 0.000 description 2
- 239000004593 Epoxy Substances 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 229910052454 barium strontium titanate Inorganic materials 0.000 description 1
- 229910002113 barium titanate Inorganic materials 0.000 description 1
- JRPBQTZRNDNNOP-UHFFFAOYSA-N barium titanate Chemical compound [Ba+2].[Ba+2].[O-][Ti]([O-])([O-])[O-] JRPBQTZRNDNNOP-UHFFFAOYSA-N 0.000 description 1
- YHWCPXVTRSHPNY-UHFFFAOYSA-N butan-1-olate;titanium(4+) Chemical compound [Ti+4].CCCC[O-].CCCC[O-].CCCC[O-].CCCC[O-] YHWCPXVTRSHPNY-UHFFFAOYSA-N 0.000 description 1
- 229910000019 calcium carbonate Inorganic materials 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000011259 mixed solution Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 239000003607 modifier Substances 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 239000002243 precursor Substances 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- 239000012798 spherical particle Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- VEALVRVVWBQVSL-UHFFFAOYSA-N strontium titanate Chemical compound [Sr+2].[O-][Ti]([O-])=O VEALVRVVWBQVSL-UHFFFAOYSA-N 0.000 description 1
- 238000000967 suction filtration Methods 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G23/00—Compounds of titanium
- C01G23/003—Titanates
- C01G23/006—Alkaline earth titanates
-
- 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
-
- 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
- C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/12—Surface area
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/80—Compositional purity
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Inorganic Chemistry (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
Abstract
The invention discloses a preparation method of spherical calcium titanate, which belongs to the technical field of filler preparation and comprises the following steps: 1. use of silane with micron-sized irregular calcium titanateThe coupling agent or silazane is subjected to surface modification, so that the agglomeration problem of the powder is improved, and the surface modified irregular calcium titanate with better dispersibility is obtained; 2. takes surface modified irregular calcium titanate as raw material, takes a flame area formed by natural gas and oxygen combustion as a spheroidization area in a spheroidization furnace, the spheroidization feeding frequency is 10-30Hz, takes oxygen or air as carrier gas to be introduced into the spheroidization area for spheroidization and cyclone classification to obtain spherical calcium titanate, the obtained spherical calcium titanate D50 is 1-5 mu m, D100 is less than 15 mu m, and the specific surface area is 0.3-1.0m 2 And/g, the purity is more than 99.5%, and the sphericity is more than 98. The calcium titanate prepared by the method has high sphericity, so that the calcium titanate has good filling quantity and fluidity, and the preparation method is simple and environment-friendly.
Description
Technical Field
The invention belongs to the technical field of filler preparation, and particularly relates to a preparation method of spherical calcium titanate.
Background
The calcium titanate has good dielectric, ferroelectric and piezoelectric properties, and is an electronic ceramic material with wide application fields; in recent years, calcium titanate has been used in microstrip antennas, and in order to obtain a high dielectric constant, it is generally necessary to add calcium titanate to increase the dielectric constant, and at present, the existing market mainly includes irregularly shaped grade calcium titanate, and the self-agglomeration phenomenon is serious, and the addition amount of calcium titanate in a resin system of a microstrip antenna substrate is limited, so that the effect of increasing the dielectric constant by adding calcium titanate is not obvious, and therefore, it is necessary to improve the fluidity to increase the addition amount, and it is urgently required to sphericize calcium titanate to meet the requirements.
Chinese patent CN 106241859B discloses a solid phase preparation method of porous calcium titanate micro-nano particle balls, which comprises the steps of adding tetrabutyl titanate and an organic mixed solution into a high-pressure reaction kettle for thermal reaction, carrying out suction filtration, precipitation and washing on an obtained product to obtain a porous submicron particle ball precursor, stirring and mixing the porous submicron particle balls and calcium carbonate, heating the mixture to a preset temperature, keeping the mixture at the preset temperature for a preset time period, and naturally cooling to obtain the porous calcium titanate micro-nano particle balls with good dispersibility.
Disclosure of Invention
In order to solve the technical problems in the background technology, the invention provides spherical calcium titanate and a preparation method thereof. The method has the advantages of simple process, small specific surface area, high sphericity and good fluidity of the prepared spherical calcium titanate, and can obviously improve the addition amount.
The technical scheme of the invention is as follows: the preparation method of the spherical calcium titanate comprises the steps of carrying out surface modification on micron-sized irregular calcium titanate by using a silane coupling agent or silazane, taking the surface-modified irregular calcium titanate as a raw material, taking a flame zone formed by burning natural gas and oxygen as a spheroidizing zone in a spheroidizing furnace, introducing oxygen or air as carrier gas into the spheroidizing zone to spheroidize, and carrying out cyclone classification on the raw material to obtain the spherical calcium titanate, wherein the indexes of the spherical calcium titanate are as follows: d50 is 1-5 μm, D100 is less than 15 μm, and specific surface area is 0.3-1.0m 2 The purity is higher than 99.5 percent, and the sphericity is higher than 98 percent.
The method comprises the following specific steps: step 1, carrying out surface modification on micron-sized irregular calcium titanate by using a silane coupling agent or silazane, and improving the agglomeration problem of powder to obtain surface modified irregular calcium titanate with better dispersibility;
step 2, taking surface modified irregular calcium titanate as a raw material, taking a flame zone formed by burning natural gas and oxygen as a spheroidizing zone in a spheroidizing furnace, introducing oxygen or air as carrier gas into the spheroidizing zone to spheroidize and cyclone-grade the raw material to obtain spherical calcium titanate D50:1-5 mu m, D100 is less than 15 mu m, and the specific surface area is 0.3-1.0m 2 The purity is higher than 99.5 percent, and the sphericity is higher than 98 percent.
Preferably, in step 1, the purity of the irregular calcium titanate is greater than 99.5%.
Preferably, in step 1, the irregular calcium titanate has d50=1.0-5.0 μm and a specific surface area of 1.0-2.0m 2 /g。
Preferably, in step 1, the silane coupling agent is alkylsilane, vinyltrimethoxysilane or vinyltriethoxysilane.
Preferably, in step 1, the silazane is hexamethyldisilazane or tetramethyldisilazane.
Preferably, the spheroidization temperature in step 1 is greater than 1980 ℃.
Preferably, the spheroidizing feed frequency in step 2 is 15-20Hz.
The invention has the following advantages:
(1) The irregular calcium titanate is modified by a silane coupling agent or silazane, so that the irregular calcium titanate has better dispersibility and fluidity, the problem of larger granularity after spheroidization caused by raw material agglomeration before spheroidization is solved, then the surface modified irregular calcium titanate is spheroidized at high temperature, and the spherical calcium titanate with stable granularity and high sphericity is obtained by adjusting and controlling spheroidization process parameters.
(2) Compared with the irregular calcium titanate raw material, the spherical calcium titanate prepared by the invention has obviously improved fluidity, obviously reduced specific surface area and viscosity.
Detailed Description
The following description of the preferred embodiments of the present invention is provided for the purpose of illustration and explanation only and is not intended to limit the present invention.
Example 1
The purity is more than 99.5%, D50=1.0-5.0 μm, and the specific surface area is 1.0-2.0m 2 And (3) carrying out high-temperature spheroidization of the irregular calcium titanate per gram at a temperature higher than 1980 ℃ with a spheroidization feeding frequency of 20Hz, and then carrying out cyclone classification to obtain spherical calcium titanate.
Example 2
The purity is more than 99.5%, D50=1.0-5.0 μm, and the specific surface area is 1.0-2.0m 2 The irregular calcium titanate of/g is subjected to surface modification by using vinyl trimethoxy silane, the adding proportion is 0.5%, the modification temperature is 110-120 ℃, the irregular calcium titanate subjected to surface modification is subjected to high-temperature spheroidization at a temperature higher than 1980 ℃, the spheroidization feeding frequency is 20Hz, and then the spherical calcium titanate is obtained through cyclone classification.
Comparative example 1
This comparative example is essentially the same as example 2, except that the spheroidization temperature is 1800-1950 ℃ only.
Comparative example 2
This comparative example is essentially the same as example 2, with the difference that the spheroidizing feed frequency is only 10Hz.
Comparative example 3
This comparative example is essentially the same as example 2, with the difference that the spheroidizing feed frequency is only 30Hz.
Comparative example 4
This comparative example is substantially the same as example 2, except that only epoxy silane was used for surface modification, the addition ratio was 0.5%, and the modification temperature was 80℃to 100 ℃.
Table 1 shows the product property data obtained for the examples and comparative examples
It can be seen from the table that, in example 1 and example 2, the irregular calcium titanate was surface-treated with vinyltrimethoxysilane before spheroidization, the particle size after spheroidization was close to the raw material particle size, the sphericity was high, the surface treatment was not performed before spheroidization, the particle size after spheroidization was significantly increased compared with that before spheroidization, and there was some irregular spherical particles due to agglomeration problem, resulting in a decrease in sphericity.
The difference in spheroidization temperature has a larger influence on sphericity and specific surface area of the final product than in comparative example 1 and example 2.
Comparative examples 2, 3 have a larger influence on the particle size, specific surface area and sphericity of the product than example 2, and the lower feed frequency of comparative example 2 has a smaller difference than example 2, but the lower feed frequency results in a lower product yield, which is not the optimal process. The higher feed frequency of comparative example 3 resulted in larger particle size and specific surface area and lower sphericity than example 2, mainly because of the increased feed amount, resulting in future and spheroidization of a part of the powder.
Comparative example 4 was surface treated with a different silane coupling agent than example 2, and the particle size and sphericity of the final product were different, comparative example 4 being larger in particle size and slightly lower in sphericity, indicating that the type of modifier affects the particle size and sphericity of the final product.
The product obtained in example 4 was already applied to the microstrip antenna substrate of the client, and compared with the irregular calcium titanate, the specific surface area of the product is obviously reduced, the fluidity is improved, the viscosity is obviously reduced, the adding proportion of the client is increased, and the dielectric property of the microstrip antenna substrate is obviously improved.
In addition, titanate having a perovskite structure such as barium titanate and strontium titanate can be spheroidized by adjusting the spheroidization process according to the above-described process.
Finally, it should be noted that: the foregoing description is only a preferred embodiment of the present invention, and the present invention is not limited thereto, but it is to be understood that modifications and equivalents of some of the technical features described in the foregoing embodiments may be made by those skilled in the art, although the present invention has been described in detail with reference to the foregoing embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
The foregoing is merely a preferred embodiment of the invention, and it should be noted that modifications could be made by those skilled in the art without departing from the principles of the invention, which modifications would also be considered to be within the scope of the invention.
Claims (7)
1. The preparation method of the spherical calcium titanate is characterized by comprising the following steps:
step 1: carrying out surface modification on the micron-sized irregular calcium titanate by using a silane coupling agent or silazane, and improving the agglomeration problem of the powder to obtain the surface modified irregular calcium titanate with better dispersibility;
step 2: the method comprises the steps of taking surface modified irregular calcium titanate as a raw material, taking a flame area formed by burning natural gas and oxygen as a spheroidizing area in a spheroidizing furnace, wherein spheroidizing feeding frequency is 10-30Hz, introducing the surface modified irregular calcium titanate into the spheroidizing area by taking oxygen or air as carrier gas, spheroidizing, cyclone grading to obtain spherical calcium titanate, wherein the D50 of the spherical calcium titanate is 1-5 mu m, D100 is less than 15 mu m, specific surface area is 0.3-1.0m < 2/g, purity is more than 99.5%, and sphericity is more than 98.
2. The method for preparing spherical calcium titanate according to claim 1, wherein the silane coupling agent in the step 1 is alkylsilane, vinyltrimethoxysilane or vinyltriethoxysilane.
3. The method for preparing spherical calcium titanate according to claim 1, wherein the silazane in the step 1 is hexamethyldisilazane or tetramethyldisilazane.
4. The method according to claim 1, wherein the spheroidization temperature in the step 2 is more than 1980 ℃.
5. The method for preparing spherical calcium titanate according to claim 1, wherein the purity of the irregular calcium titanate in the step 1 is more than 99.5%.
6. The method for preparing spherical calcium titanate according to claim 1, wherein d50=1.0 to 5.0 μm and specific surface area of the irregular calcium titanate of step 1 is 1.0 to 2.0m2/g.
7. The method for preparing spherical calcium titanate according to claim 1, wherein the spheroidization feeding frequency in the step 2 is 15-20Hz.
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| CN202210735668.5A CN115057469B (en) | 2022-06-27 | 2022-06-27 | Spherical calcium titanate preparation method |
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| CN202210735668.5A CN115057469B (en) | 2022-06-27 | 2022-06-27 | Spherical calcium titanate preparation method |
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| CN115057469B true CN115057469B (en) | 2023-12-22 |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105384177A (en) * | 2015-11-27 | 2016-03-09 | 江苏联瑞新材料股份有限公司 | Preparing method of submicrometer spherical silicon dioxide micropowder |
| CN110372913A (en) * | 2019-08-30 | 2019-10-25 | 江苏联瑞新材料股份有限公司 | A kind of Method in situ modification of electron grade spherical filler |
| CN111511686A (en) * | 2017-12-20 | 2020-08-07 | 日本化学工业株式会社 | Modified perovskite-type composite oxide, method for producing same, and composite dielectric material |
| CN215439693U (en) * | 2021-07-26 | 2022-01-07 | 江苏联瑞新材料股份有限公司 | High-purity spherical filler production purification device |
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- 2022-06-27 CN CN202210735668.5A patent/CN115057469B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105384177A (en) * | 2015-11-27 | 2016-03-09 | 江苏联瑞新材料股份有限公司 | Preparing method of submicrometer spherical silicon dioxide micropowder |
| CN111511686A (en) * | 2017-12-20 | 2020-08-07 | 日本化学工业株式会社 | Modified perovskite-type composite oxide, method for producing same, and composite dielectric material |
| CN110372913A (en) * | 2019-08-30 | 2019-10-25 | 江苏联瑞新材料股份有限公司 | A kind of Method in situ modification of electron grade spherical filler |
| CN215439693U (en) * | 2021-07-26 | 2022-01-07 | 江苏联瑞新材料股份有限公司 | High-purity spherical filler production purification device |
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