CN118343823A - Method for preparing scandium fluoride by low-temperature high-efficiency solid phase method - Google Patents
Method for preparing scandium fluoride by low-temperature high-efficiency solid phase method Download PDFInfo
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- CN118343823A CN118343823A CN202410495147.6A CN202410495147A CN118343823A CN 118343823 A CN118343823 A CN 118343823A CN 202410495147 A CN202410495147 A CN 202410495147A CN 118343823 A CN118343823 A CN 118343823A
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- fluorination
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- deamination
- scandium
- fluoride
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- OEKDNFRQVZLFBZ-UHFFFAOYSA-K scandium fluoride Chemical compound F[Sc](F)F OEKDNFRQVZLFBZ-UHFFFAOYSA-K 0.000 title claims abstract description 35
- 238000000034 method Methods 0.000 title claims abstract description 27
- 238000010532 solid phase synthesis reaction Methods 0.000 title claims abstract description 12
- 238000003682 fluorination reaction Methods 0.000 claims abstract description 51
- 230000009615 deamination Effects 0.000 claims abstract description 23
- 238000006481 deamination reaction Methods 0.000 claims abstract description 23
- MIMUSZHMZBJBPO-UHFFFAOYSA-N 6-methoxy-8-nitroquinoline Chemical compound N1=CC=CC2=CC(OC)=CC([N+]([O-])=O)=C21 MIMUSZHMZBJBPO-UHFFFAOYSA-N 0.000 claims abstract description 19
- HYXGAEYDKFCVMU-UHFFFAOYSA-N scandium oxide Chemical compound O=[Sc]O[Sc]=O HYXGAEYDKFCVMU-UHFFFAOYSA-N 0.000 claims abstract description 18
- 238000002156 mixing Methods 0.000 claims abstract description 13
- 238000004321 preservation Methods 0.000 claims abstract description 11
- 239000000203 mixture Substances 0.000 claims description 13
- 239000002245 particle Substances 0.000 claims description 12
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 10
- 230000001681 protective effect Effects 0.000 claims description 7
- 239000012298 atmosphere Substances 0.000 claims description 6
- 229910052751 metal Inorganic materials 0.000 claims description 6
- 239000002184 metal Substances 0.000 claims description 6
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims description 5
- 229910052737 gold Inorganic materials 0.000 claims description 5
- 239000010931 gold Substances 0.000 claims description 5
- 229910052697 platinum Inorganic materials 0.000 claims description 5
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 5
- 229910052721 tungsten Inorganic materials 0.000 claims description 5
- 239000010937 tungsten Substances 0.000 claims description 5
- KJTLSVCANCCWHF-UHFFFAOYSA-N Ruthenium Chemical compound [Ru] KJTLSVCANCCWHF-UHFFFAOYSA-N 0.000 claims description 3
- 229910052732 germanium Inorganic materials 0.000 claims description 3
- GNPVGFCGXDBREM-UHFFFAOYSA-N germanium atom Chemical compound [Ge] GNPVGFCGXDBREM-UHFFFAOYSA-N 0.000 claims description 3
- 229910052741 iridium Inorganic materials 0.000 claims description 3
- GKOZUEZYRPOHIO-UHFFFAOYSA-N iridium atom Chemical compound [Ir] GKOZUEZYRPOHIO-UHFFFAOYSA-N 0.000 claims description 3
- 239000000463 material Substances 0.000 claims description 3
- 229910052707 ruthenium Inorganic materials 0.000 claims description 3
- 238000002360 preparation method Methods 0.000 abstract description 8
- 238000005265 energy consumption Methods 0.000 abstract description 3
- -1 rare earth fluoride Chemical class 0.000 abstract description 3
- 229910052761 rare earth metal Inorganic materials 0.000 abstract description 3
- 230000015572 biosynthetic process Effects 0.000 abstract description 2
- 150000001875 compounds Chemical class 0.000 abstract description 2
- 238000003786 synthesis reaction Methods 0.000 abstract description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 14
- 238000004519 manufacturing process Methods 0.000 description 12
- 238000010438 heat treatment Methods 0.000 description 9
- 238000005516 engineering process Methods 0.000 description 8
- 229910052757 nitrogen Inorganic materials 0.000 description 7
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 6
- 239000001301 oxygen Substances 0.000 description 6
- 229910052760 oxygen Inorganic materials 0.000 description 6
- 239000007789 gas Substances 0.000 description 5
- 230000000630 rising effect Effects 0.000 description 5
- 229910052706 scandium Inorganic materials 0.000 description 5
- SIXSYDAISGFNSX-UHFFFAOYSA-N scandium atom Chemical compound [Sc] SIXSYDAISGFNSX-UHFFFAOYSA-N 0.000 description 5
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 4
- 239000012300 argon atmosphere Substances 0.000 description 4
- 239000012535 impurity Substances 0.000 description 4
- 238000002441 X-ray diffraction Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000012071 phase Substances 0.000 description 3
- 239000007790 solid phase Substances 0.000 description 3
- 229910052786 argon Inorganic materials 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 239000012299 nitrogen atmosphere Substances 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 1
- 229910017665 NH4HF2 Inorganic materials 0.000 description 1
- 229910018096 ScF3 Inorganic materials 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 238000013019 agitation Methods 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000004334 fluoridation Methods 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000010907 mechanical stirring Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000005477 sputtering target Methods 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 238000010792 warming Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Abstract
The invention provides a method for preparing scandium fluoride by a low-temperature high-efficiency solid phase method, and belongs to the field of rare earth fluoride preparation. The invention provides a method for preparing scandium fluoride by a low-temperature high-efficiency solid phase method, which comprises the following steps: mixing excessive ammonium bifluoride and scandium oxide, and then carrying out fluorination and deamination to obtain scandium fluoride; the temperature of the fluorination is 120-180 ℃, and the heat preservation time is 2-4 hours; the deamination temperature is 350-500 ℃ and the heat preservation time is 2-4 h. The invention can lead the fluorination to react completely within 2-4 hours by controlling the fluorination temperature to be 120-180 ℃ to generate intermediate compounds, thereby reducing the energy consumption; by controlling the deamination temperature at 350-500 ℃, the deamination is ensured to be completely reacted within 2-4 hours, scandium fluoride is obtained, the synthesis time is reduced, and the efficiency is improved. The results of the examples show that the invention realizes the low-temperature efficient fluorination of scandium fluoride.
Description
Technical Field
The invention relates to the field of rare earth fluoride preparation, in particular to a method for preparing scandium fluoride by a low-temperature high-efficiency solid phase method.
Background
Scandium is widely used in various high-tech fields such as sputtering targets, laser materials, fuel cells and high-performance alloys. Scandium fluoride is an important raw material for producing scandium by a metallothermic reduction method in the industry at present, and the production cost of scandium and the purity of final scandium are influenced by the level of the preparation technology.
Scandium fluoride preparation technology comprises three types of wet fluorination, gas phase fluorination and solid phase fluorination. The existence of a large amount of water vapor in the wet fluorination technology easily ensures that the content of oxygen impurities in scandium fluoride is high, and the purity of subsequent scandium is reduced; although the gas phase fluorination technology has the advantages of short production flow, simple operation and the like, the HF or F 2 gas used by the gas phase fluorination technology has extremely toxic and corrosive properties, is easy to harm the health of operators, pollutes the environment and has serious damage to equipment; the ammonium bifluoride solid-phase fluorination technology is the mainstream technology for producing scandium fluoride and other rare earth fluoride at present due to the advantages of simple production flow, convenient product collection, safe operation and the like.
The current ammonium bifluoride solid-phase fluorination technology mainly comprises a two-stage temperature rising and constant-temperature process: the first stage is to keep the temperature for 2-4 hours at the high temperature of 300-350 ℃; the second stage is to perform heat preservation under vacuum condition of 500-600 deg.c for 8-10 hr [ Zhang Wenyang, huang Pei, huang Meisong, etc. the fluoridation mechanism of ammonium bifluoride and scandium oxide is studied [ J ]. Hunan non-ferrous metal 2022,38 (02): 41-43 ]. In practical production, although the fluorination technique shows a certain effectiveness in realizing the fluorination reaction, the high-temperature fluorination stage (300-350 ℃) and the total reaction time as long as 15 hours not only cause huge energy consumption and high equipment maintenance cost, but also lead to prolonged production period and severely limit the production efficiency.
Disclosure of Invention
The invention aims to provide a method for preparing scandium fluoride by a low-temperature high-efficiency solid-phase method.
In order to achieve the above object, the present invention provides the following technical solutions:
the invention provides a method for preparing scandium fluoride by a low-temperature high-efficiency solid phase method, which comprises the following steps:
mixing excessive ammonium bifluoride and scandium oxide, and then carrying out fluorination and deamination to obtain scandium fluoride;
the temperature of the fluorination is 120-180 ℃, and the heat preservation time is 2-4 hours;
The deamination temperature is 350-500 ℃ and the heat preservation time is 2-4 h.
Preferably, the particle size of the ammonium bifluoride is less than 100 μm; the scandium oxide has a particle size of less than 30 μm.
Preferably, the molar ratio of the ammonium bifluoride to scandium oxide is 7-10: 1.
Preferably, the fluorination is carried out in a protective atmosphere.
Preferably, the temperature rising rate of the fluorination temperature is 5-10 ℃/min.
Preferably, the deamination pressure is 1 to 100Pa.
Preferably, the temperature rising rate of the deamination temperature is 10-20 ℃/min.
Preferably, the mixing is performed in a protective atmosphere.
Preferably, after the mixing, the method further comprises:
Placing the obtained mixture in a metal crucible for fluorination and deamination;
The purity of the crucible is greater than or equal to 99.99wt.%.
Preferably, the material of the metal crucible comprises one of tungsten, gold, platinum, iridium, germanium and ruthenium.
The invention provides a method for preparing scandium fluoride by a low-temperature high-efficiency solid phase method, which comprises the following steps: mixing excessive ammonium bifluoride and scandium oxide, and then carrying out fluorination and deamination to obtain scandium fluoride; the temperature of the fluorination is 120-180 ℃, and the heat preservation time is 2-4 hours; the deamination temperature is 350-500 ℃, the pressure is 1-100 Pa, and the heat preservation time is 2-4 h. The invention can lead the fluorination to react completely within 2-4 hours by controlling the fluorination temperature to be 120-180 ℃ to generate intermediate compounds, thereby reducing the energy consumption; by controlling the deamination temperature at 350-500 ℃, the deamination is ensured to be completely reacted within 2-4 hours, scandium fluoride is obtained, the synthesis time is reduced, and the efficiency is improved. The results of the examples show that the invention realizes the low-temperature fluorination of scandium fluoride (the temperature is reduced by about 200 ℃ compared with the temperature in the research on the fluorination reaction mechanism of ammonium bifluoride and scandium oxide), the efficient preparation (the time of the same amount of raw materials is shortened by about 50% compared with the prior art), and the high fluorination rate (more than 99.7%, and the fluorination rate in the prior art is about 99.2%).
Drawings
FIG. 1 is a flow chart of the present invention;
FIG. 2 is a schematic diagram of the product of example 1;
FIG. 3 is an XRD pattern of the product obtained in example 1;
FIG. 4 is an XRD pattern of the product obtained in example 2;
figure 5 is an XRD pattern of the product obtained in example 3.
Detailed Description
The invention provides a method for preparing scandium fluoride by a low-temperature high-efficiency solid phase method, which comprises the following steps:
And (3) mixing ammonium bifluoride and scandium oxide, and then carrying out fluorination and deamination to obtain scandium fluoride.
In the present invention, the molar ratio of ammonium bifluoride to scandium oxide is preferably 7 to 10:1, more preferably 7.2 to 9.6:1, still more preferably 8 to 9:1; the particle diameter of the ammonium bifluoride is preferably less than 100. Mu.m, more preferably 20 to 80. Mu.m, still more preferably 40 to 60. Mu.m; the particle size of scandium oxide is preferably less than 30. Mu.m, more preferably 5 to 25. Mu.m, and still more preferably 10 to 15. Mu.m.
In the present invention, the mixing is performed in a protective atmosphere; the mixing time is preferably 5 to 15 minutes, more preferably 10 to 15 minutes; the apparatus for mixing preferably includes a mechanical agitation type mixer, an air flow type mixer or a rotary type mixer.
In the present invention, after the mixing, the method further comprises:
Placing the obtained mixture in a metal crucible for fluorination and deamination;
the purity of the metal crucible is preferably 99.99wt.% or more; the crucible is preferably made of one of tungsten, gold, platinum, iridium, germanium and ruthenium.
In the present invention, the fluorination is preferably performed in a protective atmosphere; other preferred protective atmospheres include nitrogen, argon or a mixture of nitrogen and argon; the temperature of the fluorination is 120-180 ℃, preferably 150-170 ℃, more preferably 155-160 ℃; the pressure is preferably atmospheric pressure; the heat preservation time is preferably 2 to 4 hours, more preferably 2.5 to 3 hours; the heating rate to the fluorination temperature is preferably 5 to 10 ℃, more preferably 6 to 9 ℃, and even more preferably 7 to 8 ℃.
In the present invention, the following reaction may occur during the warming to the fluorination temperature:
NH4HF2+Sc2O3→(NH4)3ScF6；
if ammonium bifluoride is excessive, the following reaction occurs when Sc 2O3 is excessive:
(NH4)3ScF6+Sc2O3→(NH4)5Sc3F14。
In the present invention, the deamination temperature is preferably 350 to 500 ℃, more preferably 350 to 450 ℃, still more preferably 360 to 400 ℃; the pressure is preferably 1 to 100Pa, more preferably 20 to 80Pa, still more preferably 40 to 60Pa; the heat preservation time is 2-4 hours, preferably 2.5-3 hours; the heating rate to the deamination temperature is preferably 10 to 20 ℃, more preferably 12 to 18 ℃, and even more preferably 13 to 15 ℃.
The deamination process may take place as follows:
(NH4)5Sc3F14/(NH4)3ScF6→NH4ScF4→(NH4)2Sc3F11→NH4Sc3F10
(180～350℃)；
NH4Sc3F10→ScF3(350～500℃)。
the method for preparing scandium fluoride by using the low-temperature high-efficiency solid phase method is shown in figure 1.
The method for preparing scandium fluoride by the low-temperature high-efficiency solid phase method provided by the invention is described in detail below with reference to examples, but they are not to be construed as limiting the scope of the invention.
Example 1
S1: ammonium bifluoride (particle size 50 μm) and scandium oxide (particle size 5 μm) in a molar ratio of 8.4:1 were thoroughly mixed in an argon atmosphere having a purity of 99.99wt.% using a mechanical stirring mixer for 10min to give 100g of a mixture;
S2: heating the mixture to 160 ℃ at a heating rate of 5 ℃/min in a tungsten crucible with the purity of 99.99wt.% under the condition of normal pressure in an argon atmosphere with the purity of 99.99wt.% for 2h of fluorination;
S3: the mixture was deaminated in a tungsten crucible having a purity of 99.99wt.% under vacuum at a temperature rising rate of 10 ℃/min to 400 ℃ for 2h under a vacuum condition of 20Pa to obtain a product.
The fluorination rate of the product is 99.7%; the physical pattern of the product is shown in FIG. 2, and XRD is shown in FIG. 3.
As can be seen from fig. 3, all diffraction peaks are characteristic peaks of scandium fluoride, and no other impurity peaks exist; the oxygen content of the product was 0.505wt.%; the nitrogen content of the product was 0.356wt.%.
Therefore, the embodiment 1 realizes the low-temperature efficient preparation of scandium fluoride, has high fluorination rate, improves the production efficiency, reduces the production cost of scandium fluoride, and has remarkable economic effect.
Example 2
S1: ammonium bifluoride (particle size: 30 μm) and scandium oxide (particle size: 10 μm) in a molar ratio of 8.4:1 were thoroughly mixed in a nitrogen atmosphere having a purity of 99.99wt.% using a gas flow mixer for 15min to obtain 10g of a mixture;
S2: heating the mixture to 170 ℃ at a heating rate of 10 ℃/min in a gold crucible with the purity of 99.99wt.% under the normal pressure condition in a nitrogen atmosphere with the purity of 99.99wt.% for 2h of fluorination;
S3: the mixture was deaminated in a gold crucible having a purity of 99.99wt.% under a vacuum of 5Pa at a temperature rising rate of 15 ℃/min to 500 ℃ for 2h to obtain the product.
The fluorination rate of the product is 99.8%; XRD of the product is shown in figure 4.
As can be seen from fig. 4, all diffraction peaks are characteristic peaks of scandium fluoride, and no other impurity peaks exist; the oxygen content of the product was 0.556wt.%; the nitrogen content of the product was 0.319wt.%.
It can be seen that: the embodiment 2 realizes the low-temperature efficient preparation of scandium fluoride, has high fluorination rate, improves the production efficiency, reduces the production cost of scandium fluoride, and has remarkable economic effect.
Example 3
S1: ammonium bifluoride (particle size 50 μm) and scandium oxide (particle size 10 μm) in a molar ratio of 7.2:1 were thoroughly mixed in an argon atmosphere having a purity of 99.99wt.% using a rotary mixer for 15min to obtain 100g of a mixture;
S2: heating the mixture to 160 ℃ at a heating rate of 5 ℃/min in a platinum crucible with the purity of 99.99wt.% under the condition of normal pressure in an argon atmosphere with the purity of 99.99wt.% for 2h of fluorination;
s3: the mixture was deaminated under vacuum conditions of 20Pa in a platinum crucible having a purity of 99.99wt.% at a heating rate of 10℃per minute to 400℃for 3h to give the product.
The fluorination rate of the product is 99.7%; XRD of the product is shown in figure 5.
As can be seen from fig. 5, all diffraction peaks are characteristic peaks of scandium fluoride, and no other impurity peaks exist; the oxygen content of the product was 0.476wt.%; the nitrogen content of the product was 0.375wt.%.
Therefore, the embodiment 3 realizes the low-temperature efficient preparation of scandium fluoride, has high fluorination rate, improves the production efficiency, reduces the production cost of scandium fluoride, and has remarkable economic effect.
TABLE 1 fluorination Rate, oxygen content and Nitrogen content of the products of the prior art and examples 1 to 3
| Fluorination Rate (%) | Oxygen content (wt.%) | Nitrogen content (wt.%) | |
| Prior Art | 99.2 | - | - |
| Example 1 | 99.7 | 0.505 | 0.356 |
| Example 2 | 99.8 | 0.556 | 0.319 |
| Example 3 | 99.7 | 0.476 | 0.375 |
The foregoing is merely a preferred embodiment of the present invention and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present invention, which are intended to be comprehended within the scope of the present invention.
Claims (10)
1. The method for preparing scandium fluoride by using the low-temperature high-efficiency solid phase method is characterized by comprising the following steps of:
mixing excessive ammonium bifluoride and scandium oxide, and then carrying out fluorination and deamination to obtain scandium fluoride;
the temperature of the fluorination is 120-180 ℃, and the heat preservation time is 2-4 hours;
The deamination temperature is 350-500 ℃ and the heat preservation time is 2-4 h.
2. The method according to claim 1, wherein the ammonium bifluoride has a particle size of less than 100 μm; the scandium oxide has a particle size of less than 30 μm.
3. The method according to claim 1 or 2, characterized in that the molar ratio of ammonium bifluoride to scandium oxide is 7-10: 1.
4. The method of claim 1, wherein the fluorination is conducted in a protective atmosphere.
5. The method according to claim 1, wherein the temperature rise rate to the fluorination temperature is 5 to 10 ℃/min.
6. The method according to claim 1, wherein the deamination pressure is 1 to 100Pa .
7. The method according to claim 1, wherein the rate of temperature rise to the deamination temperature is 10-20 ℃/min.
8. The method of claim 1, wherein the mixing is performed in a protective atmosphere.
9. The method of claim 1 or 8, wherein after the mixing, further comprising:
Placing the obtained mixture in a metal crucible for fluorination and deamination;
The purity of the crucible is greater than or equal to 99.99wt.%.
10. The method of claim 9, wherein the material of the metallic crucible comprises one of tungsten, gold, platinum, iridium, germanium, and ruthenium.
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN118343823A true CN118343823A (en) | 2024-07-16 |
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