CN114920248A - Synthetic method of silicon tetrafluoride - Google Patents
Synthetic method of silicon tetrafluoride Download PDFInfo
- Publication number
- CN114920248A CN114920248A CN202210790243.4A CN202210790243A CN114920248A CN 114920248 A CN114920248 A CN 114920248A CN 202210790243 A CN202210790243 A CN 202210790243A CN 114920248 A CN114920248 A CN 114920248A
- Authority
- CN
- China
- Prior art keywords
- reactor
- silicon tetrafluoride
- cold trap
- temperature
- silicon
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/08—Compounds containing halogen
- C01B33/107—Halogenated silanes
- C01B33/10705—Tetrafluoride
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Silicon Compounds (AREA)
Abstract
The invention discloses a method for synthesizing silicon tetrafluoride, which comprises the following steps: adding silicon powder into a reactor for pretreatment, heating the reactor, purging with inert gas, removing water and air in the reactor, after the reactor is cooled to room temperature, replacing the reactor with inert gas, and introducing fluorine gas into the reactor for reaction to obtain silicon tetrafluoride; and introducing the obtained silicon tetrafluoride into a cold trap for collection. The method has the advantages of simple conditions, no by-product and low energy consumption.
Description
Technical Field
The invention belongs to the technical field of fluoride preparation, and particularly relates to a synthesis method of silicon tetrafluoride.
Background
Silicon tetrafluoride is widely applied to the electronic and semiconductor industries, is an important raw material for preparing silane, crystalline silicon, optical fibers and the like, can also be used for preparing hardening agents, photosensitizers and the like of cement and marble, and has wide application prospects in the microelectronic industry.
Various methods for producing silicon tetrafluoride have been disclosed in the literature or patents at present. However, the high-temperature pyrolysis energy consumption of the fluorosilicate pyrolysis method is high; the sulfuric acid method has serious environmental pollution; the hydrofluoric acid method also needs to be heated to 200-300 ℃ for a long time, the energy consumption is high, and the cost of anhydrous hydrofluoric acid is high. Therefore, it is significant to develop a simple silicon tetrafluoride synthesis method with low energy consumption.
Disclosure of Invention
The technical problem to be solved by the present invention is to provide a method for synthesizing silicon tetrafluoride by fluorine gas (F) 2 ) Directly reacting with silicon (Si) simple substance to prepare crude silicon tetrafluoride (SiF) 4 ) Gas, simple method and low energy consumption.
In order to solve the technical problems, the invention adopts the technical scheme that: a method for synthesizing silicon tetrafluoride, which is characterized by comprising the following steps:
s1, adding silicon powder into a reactor, heating the reactor to 200-300 ℃, purging with inert gas, stopping heating after purging, and replacing the reactor with the inert gas when the temperature of the reactor is reduced to room temperature;
s2, mixing F 2 Introducing the mixture into a reactor after replacement for reaction, and controlling the temperature of the reactor to be 10-50 ℃ to obtain silicon tetrafluoride and light components;
the reaction principle in S2 is: 2F 2 +Si→SiF 4
And S3, introducing the silicon tetrafluoride and light components obtained in the S2 into a cold trap, and emptying the light components to obtain a crude product of the silicon tetrafluoride.
Preferably, the particle size of the silicon powder in S1 is 0.1 mm-3 mm.
Preferably, the purity of the inert gas in S1 is 99.999%, and the inert gas is nitrogen, helium or argon.
Preferably, the sweeping speed of the blowing in the S1 is 1L/h-10L/h, and the time is 2-8 h.
Preferably, the number of times of substitution in S1 is 10 to 20 times.
Preferably(iii) F in S2 2 Is 98%, said F 2 The flow rate of (A) is 1L/min to 10L/min.
Preferably, the silicon powder in S1 and the F in S2 2 In a molar ratio of 1: 2.
Preferably, the cold trap in S3 comprises a cold trap kettle and a cold trap column, wherein the temperature of the cold trap kettle is-120 ℃ to-65 ℃, and the temperature of the cold trap column is-70 ℃ to-50 ℃.
Compared with the prior art, the invention has the following advantages:
1. the invention can remove water and air in the reactor by heating and purging the reactor, thereby preventing the influence of impurities for ensuring the subsequent reaction.
2. According to the method, silicon powder and fluorine gas are directly reacted at normal temperature to generate the silicon tetrafluoride, and the method is simple in condition, free of by-products and low in energy consumption.
The technical solution of the present invention is further described in detail by the accompanying drawings and examples.
Drawings
FIG. 1 is a schematic flow diagram of a process for the synthesis of silicon tetrafluoride according to the invention.
Description of the reference numerals:
1-a reactor; 2-a feed inlet; 3, a dust remover; 4-cold trap.
Detailed Description
Example 1
The synthesis method of silicon tetrafluoride in the embodiment comprises the following steps:
s1, adding silicon powder with the particle size of 1mm into a reactor 1 from a feeding port 2, maintaining pressure and detecting leakage, heating the reactor 1 to 200 ℃, purging the reactor 1 with nitrogen with the purity of 99.999 percent at a purging speed of 1L/h for 8h, stopping heating after purging, and replacing the reactor 1 with the nitrogen with the purity of 99.999 percent for 10 times when the temperature of the reactor 1 is reduced to room temperature (25 ℃); the purpose of the purge is to remove water and air from the reactor 1;
s2, mixing F with the purity of 98% 2 Introducing the mixture into the reactor 1 after replacement for reaction, and simultaneously carrying out reactionOpening cooling circulating water, and controlling the temperature of the reactor 1 to be 10 ℃ to obtain silicon tetrafluoride and light components; said F 2 The flow rate of (2) is 2L/min; the light components comprise hydrogen and nitrogen, the hydrogen is obtained by heating a small amount of water which is not completely removed in the reactor 1, and the nitrogen is a small amount of nitrogen left in replacement;
silicon powder described in S1 and F described in S2 2 In a molar ratio of 1: 2;
s3, filtering the silicon tetrafluoride and the light components obtained in the S2 by a dust remover 3, and introducing the filtered silicon tetrafluoride and the light components into a cold trap 4, wherein the cold trap 4 comprises a cold trap kettle and a cold trap column, and after the light components are discharged from the top of the cold trap column to three wastes, crude silicon tetrafluoride is obtained and collected to the cold trap kettle; the temperature of the cold trap kettle is-65 ℃, and the temperature of the cold trap column is-50 ℃.
Through detection: the purity of the crude silicon tetrafluoride obtained in S3 was 97.1%.
In this embodiment, the particle size of the silicon powder may also be 0.1mm, 0.5mm, 0.8mm, or 1.5 mm; the sweeping speed of the purging can also be 2L/h, 3L/h, 4L/h, 6L/h, 7L/h, 8L/h or 9L/h, and the time can also be 4h, 5h, 6h or 7 h; said F 2 The flow rate of (2) may also be 1L/min, 3L/min, 4L/min, 6L/min, 7L/min, 8L/min or 9L/min.
Example 2
The synthesis method of silicon tetrafluoride in the embodiment comprises the following steps:
s1, adding silicon powder with the particle size of 2mm into a reactor 1 from a feed inlet 2, maintaining pressure and detecting leakage, heating the reactor 1 to 240 ℃, purging with helium with the purity of 99.999% at the purging speed of 10L/h for 2h, stopping heating after purging, and replacing the reactor 1 with the helium with the purity of 99.999% for 20 times when the temperature of the reactor 1 is reduced to room temperature (25 ℃);
s2, mixing F with the purity of 98% 2 Introducing the mixture into the reactor 1 after replacement for reaction, simultaneously opening cooling circulating water, and controlling the temperature of the reactor 1 to be 30 ℃ to obtain silicon tetrafluoride and light components; said F 2 The flow rate of (2) is 5L/min; the light component comprises hydrogen and helium, and the hydrogen is in the reactor 1A small amount of moisture which is not completely removed is heated to obtain helium which is a small amount of helium left in the replacement process;
silicon powder described in S1 and F described in S2 2 In a molar ratio of 1: 2;
s3, filtering the silicon tetrafluoride and the light components obtained in the S2 by a dust remover 3, and introducing the filtered silicon tetrafluoride and the light components into a cold trap 4, wherein the cold trap 4 comprises a cold trap kettle and a cold trap column, and after the light components are discharged from the top of the cold trap column to three wastes, crude silicon tetrafluoride is obtained and collected to the cold trap kettle; the temperature of the cold trap kettle is-120 ℃, and the temperature of the cold trap column is-70 ℃.
Through detection: the purity of the crude silicon tetrafluoride obtained in S3 was 97.4%.
Example 3
The synthesis method of silicon tetrafluoride in the embodiment comprises the following steps:
s1, adding silicon powder with the particle size of 3mm into a reactor 1 from a feeding port 2, maintaining pressure and detecting leakage, heating the reactor 1 to 300 ℃, purging with argon with the purity of 99.999 percent at the purging speed of 5L/h for 3h, stopping heating after purging, and replacing the reactor 1 with the argon with the purity of 99.999 percent for 15 times when the temperature of the reactor 1 is reduced to room temperature (24 ℃);
s2, mixing F with the purity of 98% 2 Introducing the mixture into the reactor 1 after replacement for reaction, simultaneously opening cooling circulating water, and controlling the temperature of the reactor 1 to be 50 ℃ to obtain silicon tetrafluoride and light components; said F 2 The flow rate of (2) is 10L/min; the light components comprise hydrogen and argon, the hydrogen is obtained by heating a small amount of water which is not completely removed in the reactor 1, and the argon is a small amount of argon left during replacement;
silicon powder described in S1 and F described in S2 2 In a molar ratio of 1: 2;
s3, filtering the silicon tetrafluoride and the light components obtained in the step S2 by a dust remover 3, and introducing the filtered silicon tetrafluoride and the light components into a cold trap 4, wherein the cold trap 4 comprises a cold trap kettle and a cold trap column, and after the light components are discharged from the top of the cold trap column to three wastes, crude silicon tetrafluoride is obtained and collected to the cold trap kettle; the temperature of the cold trap kettle is-100 ℃, and the temperature of the cold trap column is-60 ℃.
And (3) detection: the purity of the crude silicon tetrafluoride obtained in S3 was 96.7%.
In examples 1-3, the top of the reactor 1 used was provided with three feed ports 2 for the addition of silicon powder; the reactor 1 is a stainless steel cylinder, the outer wall of the reactor is provided with a jacket, the jacket is connected with cooling water, and the temperature of the reactor 1 is kept between 0 ℃ and 50 ℃.
The above description is only for the preferred embodiment of the present invention, and is not intended to limit the present invention in any way. Any simple modification, change and equivalent changes of the above embodiments according to the technical essence of the invention are still within the protection scope of the technical solution of the invention.
Claims (8)
1. A method for synthesizing silicon tetrafluoride, which is characterized by comprising the following steps:
s1, adding silicon powder into a reactor, heating the reactor to 200-300 ℃, purging with inert gas, stopping heating after purging, and replacing the reactor with the inert gas when the temperature of the reactor is reduced to room temperature;
s2, mixing F 2 Introducing the mixture into a reactor after replacement for reaction, and controlling the temperature of the reactor to be 10-50 ℃ to obtain silicon tetrafluoride and light components;
and S3, introducing the silicon tetrafluoride and the light component obtained in the S2 into a cold trap, and emptying the light component to obtain a crude product of the silicon tetrafluoride.
2. The method for synthesizing silicon tetrafluoride according to claim 1, wherein the particle size of the silicon powder in S1 is 0.1mm to 3 mm.
3. The method as claimed in claim 1, wherein the purity of the inert gas in the step S1 is 99.999%, and the inert gas is nitrogen, helium or argon.
4. The method for synthesizing silicon tetrafluoride according to claim 1, wherein the sweeping speed of the blowing in S1 is 1-10L/h, and the time is 2-8 h.
5. The method according to claim 1, wherein the number of times of substitution in S1 is 10 to 20.
6. The method as claimed in claim 1, wherein the silicon powder in S1 and the F in S2 are mixed together to form the silicon tetrafluoride 2 In a molar ratio of 1: 2.
7. The method as claimed in claim 1, wherein F in S2 is F 2 Has a purity of 98%, said F 2 The flow rate of (A) is 1L/min to 10L/min.
8. The method as claimed in claim 1, wherein the cold trap in S3 comprises a cold trap kettle and a cold trap column, the temperature of the cold trap kettle is-120 ℃ to-65 ℃, and the temperature of the cold trap column is-70 ℃ to-50 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210790243.4A CN114920248A (en) | 2022-07-05 | 2022-07-05 | Synthetic method of silicon tetrafluoride |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210790243.4A CN114920248A (en) | 2022-07-05 | 2022-07-05 | Synthetic method of silicon tetrafluoride |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114920248A true CN114920248A (en) | 2022-08-19 |
Family
ID=82816206
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210790243.4A Pending CN114920248A (en) | 2022-07-05 | 2022-07-05 | Synthetic method of silicon tetrafluoride |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114920248A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115318234A (en) * | 2022-08-31 | 2022-11-11 | 神华准能资源综合开发有限公司 | Gallium chloride preparation system |
-
2022
- 2022-07-05 CN CN202210790243.4A patent/CN114920248A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115318234A (en) * | 2022-08-31 | 2022-11-11 | 神华准能资源综合开发有限公司 | Gallium chloride preparation system |
| CN115318234B (en) * | 2022-08-31 | 2024-04-30 | 神华准能资源综合开发有限公司 | Gallium chloride preparation system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3751326B2 (en) | Manufacturing method of high purity transparent quartz glass | |
| CN102030329B (en) | Polycrystalline silicon producing device and process | |
| WO2018113478A1 (en) | Method for producing lithium hydroxide monohydrate using lithium carbonate as raw material | |
| CN114920248A (en) | Synthetic method of silicon tetrafluoride | |
| CN113651341A (en) | Method for synthesizing lithium hexafluorophosphate solution by using fluorine-containing waste residues | |
| CN105197966B (en) | A kind of purification process of super-active lithium fluoride | |
| CN101531367B (en) | Process for producing silicane | |
| JP2001220126A (en) | Crystalline synthetic silica powder and glass compact using the same | |
| JP2001220157A (en) | Amorphous synthetic silica powder and glass compact using the same | |
| RU2330811C2 (en) | Method of obtaining high-purity lithium fluoride | |
| CN114715850A (en) | Method for synthesizing chlorine trifluoride with high yield | |
| CN102502530A (en) | Method for producing electronic-grade sulfuric acid by static fusion crystallization | |
| CN111204801B (en) | Phosphoric acid method production process of zirconia powder of high-silicon zirconium-containing waste | |
| CN101708852B (en) | Method for purifying liquid phase silica recovered from solar polysilicon tail gas | |
| CN106220534A (en) | The preparation facilities of a kind of biruea and preparation method | |
| CN101293654A (en) | Industrial silicon pressurization purification method | |
| CN111762787B (en) | Combined preparation method of chlorosilane and quartz | |
| CN103879977B (en) | A kind of continuous production method of high pure nitric acid and production equipment | |
| CN113526544A (en) | Method for preparing high-purity germanium tetrafluoride by thermal decomposition of barium fluorogermanate | |
| CN112960673A (en) | Process for preparing 4H silicon carbide electronic material by in-situ synthesis method | |
| CN213326765U (en) | Device for producing low-silicon dry-process aluminum fluoride by using high-silicon fluorite powder | |
| CN117208915A (en) | High-purity optical coated silicon dioxide and preparation method thereof | |
| CN203678355U (en) | High-temperature gas-solid reaction device for high-purity quartz sand | |
| KR101615307B1 (en) | Polysilicon production apparatus | |
| CN107055552A (en) | A kind of purification method of silicon tetrachloride and application |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication |