CN112158850A - Method for preparing anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas by using phosphorus ore associated fluorine - Google Patents
Method for preparing anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas by using phosphorus ore associated fluorine Download PDFInfo
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Abstract
The invention discloses a method for preparing anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas by using phosphorus ore associated fluorine, and belongs to the technical field of phosphorus chemical industry. The method comprises the following steps: (1) after uniformly stirring the water-containing fluosilicic acid, adding washing sulfuric acid for reaction to obtain a gas mixture of fluorine-containing sulfuric acid, water-containing silicon tetrafluoride and hydrogen fluoride, wherein the washing sulfuric acid comes from step (3), the fluosilicic acid is selected from one or two of fluosilicic acid and fluorosilicate, and the mass ratio of water in the water-containing fluosilicic acid to the washing sulfuric acid is 1-3: 7; (2) heating the fluorine-containing sulfuric acid obtained in the step (1) at the temperature of 160-220 ℃ to obtain 70-80wt% of sulfuric acid and mixed gas of water-containing silicon tetrafluoride and hydrogen fluoride, wherein the 70-80wt% of sulfuric acid is used for preparing phosphoric acid; (3) and (3) washing the mixed gas obtained in the step (1) and the step (2) by using hot concentrated sulfuric acid to obtain a mixed gas of anhydrous silicon tetrafluoride and hydrogen fluoride, and washing sulfuric acid to be sent to the step (1).
Description
Technical Field
The invention relates to the technical field of phosphorus chemical industry, in particular to a method for preparing anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas by using phosphorus ore associated with fluorine.
Background
The hydrogen fluoride is a basic raw material of fluorine chemical industry, is also the only raw material for manufacturing the element fluorine, and can be used for producing important products required by various industries such as aerosol, metal cleaning agent, plastic foaming agent, surfactant, polytetrafluoroethylene and the like. Hydrogen fluoride is often used as a raw material for fluorine-containing catalysts, and can be used as a catalyst in alkylation, isomerization or polymerization of organic compounds; hydrogen fluoride is also a basic raw material for the nuclear industry to manufacture uranium hexafluoride, and high-purity or ultrapure hydrogen fluoride has been used in the optical, microelectronic and fine chemical industries. As the production and demand for fluorochemicals increases year by year, the demand for hydrogen fluoride also increases year by year. However, in recent years, the productivity of fluorine chemical plants has been increasing due to the scarcity of fluorite, but the operating rate has been insufficient, so that the supply of hydrogen fluoride is in short supply and the price has been historically high.
Silicon tetrafluoride is one of the important chemical materials in the field of fluorine chemical industry, is mainly applied to the electronic and semiconductor industries, is used for an etchant of silicon nitride, a P-type dopant, an epitaxial deposition diffusion silicon source and the like, and can also be used for preparing electronic-grade silane or silicon. With the rapid development of the electronic industry in the world, the demand of silicon tetrafluoride in the market is gradually increased.
A large amount of fluosilicic acid, sodium fluosilicate and other fluosilicic acid substances can be generated in the production process of the wet-process phosphoric acid. Most fluosilicic acid with the concentration of about 12 percent is used for producing Na2SiF6The value is low, the processing mode enables part of enterprises to be in a loss state, and the utilization enthusiasm is not highAnd a part of enterprises can even be directly added into the phosphorus compound fertilizer, so that a great deal of waste of fluorine resources and silicon resources is caused. At present, only a few enterprises produce by-product fluorine resources with the concentration of 18 percent fluosilicic acid for processing and utilization, five sets of devices are built in Guizhou, Yunnan and Hubei represented by Guizhou Van Fulan chemical Limited company, the utilization rate of the fluosilicic acid only accounts for about 20 percent of national by-products, 80 percent of the fluosilicic acid in the national range is influenced by factors such as concentration, transportation distance and the like, and the fluosilicic acid is only used as an environmental protection project for simple treatment.
The technology for decomposing concentrated fluosilicic acid by concentrated sulfuric acid in Guizhou Vanfu blue sky has the advantage of low cost in the aspect of utilization of associated fluorine of phosphorite. According to the technology, 30% of fluosilicic acid is decomposed by 98% of sulfuric acid, the obtained silicon tetrafluoride is absorbed by 18% of fluosilicic acid to obtain 30% of fluosilicic acid, the rest hydrogen fluoride-sulfuric acid-water system is subjected to high temperature to obtain hydrogen fluoride crude gas, and then the crude gas is rectified to obtain industrial-grade hydrogen fluoride. But is influenced by the factors of high raw material requirement (the concentration of the fluosilicic acid must reach 18 percent and is difficult to reach by most enterprises), the transportation distance of the fluosilicic acid, high treatment cost of the byproduct silica gel, large amount of byproduct dilute sulfuric acid (about 27 tons of 70 percent sulfuric acid by 1 ton of hydrogen fluoride), and the like, so the application range is very limited.
Patent No. CN201110446235 discloses a method for preparing silicon tetrafluoride and hydrogen fluoride by taking sodium fluosilicate as a raw material, which comprises the steps of adding dried sodium fluosilicate and sulfuric acid into a brick kiln reactor according to the molar ratio of 1:1, reacting at the temperature of 160-220 ℃, then removing dust, pressurizing and pre-cooling to-30 ℃, and then sending mixed gas to a rectifying tower for separation to respectively obtain anhydrous hydrogen fluoride and silicon tetrafluoride. The method has the disadvantages that firstly, a converter is used as a reactor, so that the energy consumption utilization rate is extremely low and is only about 25%; secondly, after being mixed, the concentrated sulfuric acid and the sodium fluosilicate have very high viscosity and are easy to bond on the inner wall of the brick kiln, and finally, the heat exchange performance of the kiln wall is poor, so that normal production cannot be realized; ③ can only be applied to solid sodium fluosilicate, but not applied to fluosilicic acid.
Therefore, it is necessary to research and invent a method suitable for both fluorosilicic acid and fluorosilicate to overcome the disadvantages of the above processes, so as to achieve the simultaneous high-efficiency utilization and wide application of fluorine and silicon resources in industry.
Disclosure of Invention
The invention aims to overcome the technical defect of the by-product fluosilicic acid in the existing wet-process phosphoric acid production process and provide a method which is more economic and effective, has wider application range and higher resource utilization rate. The separation method of the anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas is mature, so that the hydrogen fluoride and silicon tetrafluoride products are easily obtained. The scheme is as follows:
the embodiment of the invention provides a method for preparing anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas by phosphorus ore associated with fluorine, which comprises the following steps:
(1) after the hydrous fluosilicic acid is stirred uniformly, washing sulfuric acid (excessive) is added for reaction, and the mixed gas of fluorine-containing sulfuric acid, hydrous silicon tetrafluoride and hydrogen fluoride is obtained. Wherein the washing sulfuric acid is from step (3) (in the embodiment, excessive washing sulfuric acid is needed to generate a large amount of by-product sulfuric acid), the fluosilicic acid is selected from one or two of fluosilicic acid and fluorosilicate, the mass ratio of water in the aqueous fluosilicic acid to the washing sulfuric acid is 1-3:7 to ensure the concentration of the reacted sulfuric acid (simultaneously, the fluosilicic acid is uniformly mixed to ensure the reaction to be smoothly carried out; and the concentration of the sulfuric acid is also needed to ensure the decomposition reaction to be smoothly carried out), and the fluorine content in the aqueous fluosilicic acid is more than or equal to 24wt% (usually less than 60%) to ensure the concentration of the reacted sulfuric acid. In the step, silicon tetrafluoride, a small amount of hydrogen fluoride and water are mainly obtained.
(2) Heating the fluorine-containing sulfuric acid obtained in the step (1) at the temperature of 160-220 ℃ to obtain 70-80wt% of sulfuric acid and mixed gas of aqueous silicon tetrafluoride and hydrogen fluoride, wherein 70-80wt% of sulfuric acid is used for preparing phosphoric acid and is usually sent to an extraction process to react with phosphorite slurry, and the sulfate generated by the reaction of the method does not influence the preparation of the phosphoric acid (sulfate ions are removed in the form of phosphogypsum). In the step, hydrogen fluoride, water and a small amount of silicon tetrafluoride are mainly obtained.
And (3) cutting silicon tetrafluoride from water in the steps (1) and (2), so that the situation that the silicon tetrafluoride and the water form fluorosilicone ether to block a pipeline is avoided.
(3) And (3) washing the mixed gas obtained in the step (1) and the step (2) by using hot concentrated sulfuric acid to obtain a mixed gas of anhydrous silicon tetrafluoride and hydrogen fluoride, and sending the washed sulfuric acid to the step (1). Wherein the concentration of the hot concentrated sulfuric acid is 90-105wt%, and the temperature is 160-220 ℃.
Wherein, in the step (1), the aqueous fluosilicic acid is a mixture of fluosilicate and water, a mixture of fluosilicate and fluosilicic acid or a mixture of fluosilicate, fluosilicic acid and water.
Specifically, the concentration of the fluosilicic acid in the embodiment of the present invention is 2 to 25wt% (usually, the concentration of the fluosilicic acid as a by-product of phosphoric acid is 2 to 18 wt%), and the fluosilicate is an alkali metal fluosilicate or an alkaline earth metal fluosilicate.
Preferably, the fluosilicic acid in the embodiment of the invention is a phosphoric acid by-product fluosilicic acid; the fluorosilicate is obtained by reacting fluosilicic acid as a by-product of phosphoric acid with sodium chloride, and may be dried or not dried (preferably not dried).
Specifically, the fluorosilicate in the embodiment of the present invention is selected from sodium fluorosilicate, potassium fluorosilicate, magnesium fluorosilicate, calcium fluorosilicate, or the like.
Preferably, the aqueous fluosilicic acid product in the embodiment of the invention is a mixture of phosphoric acid by-product fluosilicic acid and fluorosilicate obtained by reaction, which can maximally utilize phosphoric acid by-product fluoride, ensure the concentration of sulfuric acid after reaction for reuse, and reduce the treatment cost.
Wherein, in the step (1), the reaction temperature is 70-160 ℃, and the heat comes from the self-carrying heat and the dilution heat of the washing sulfuric acid without additional heating.
Wherein, in the step (1), the reaction time is 30-120 min.
Wherein, in the step (2), the heating time is 10-60 min.
Specifically, the method provided by the invention comprises the following steps:
(1) after the hydrous fluosilicic acid is stirred uniformly, washing sulfuric acid is added for reaction for 30-120min, and the mixed gas of fluorine-containing sulfuric acid, hydrous silicon tetrafluoride and hydrogen fluoride is obtained. Wherein the washing sulfuric acid is obtained from the step (3), the hydrous fluosilicic acid product is a mixture of fluosilicic acid as a phosphoric acid by-product and a fluosilicate obtained by reaction (preferably not dried, containing about 10% of water, and dried if long-distance transportation is required), the mass ratio of water in the hydrous fluosilicic acid product to the washing sulfuric acid is 1-3:7, and the content of fluorine in the hydrous fluosilicic acid product is more than or equal to 24 wt%.
(2) Heating the fluorine-containing sulfuric acid obtained in the step (1) at the temperature of 160-.
(3) And (3) washing the mixed gas obtained in the step (1) and the step (2) by using hot concentrated sulfuric acid to obtain a mixed gas of anhydrous silicon tetrafluoride and hydrogen fluoride, and sending the washed sulfuric acid to the step (1). Wherein the concentration of the hot concentrated sulfuric acid is 90-105wt%, and the temperature is 160-220 ℃.
The invention has the following innovation points:
(1) because the fluosilicate is used as the raw material, the limit of the transportation distance of the fluosilicic acid is overcome, and the centralized utilization of the fluosilicic acid in the national range can be realized.
(2) The fluosilicic acid and the fluosilicate are used in a matching way, so that the fluorine concentration in a fluosilicic acid substance/water mixture can easily reach more than 24 percent, the range of raw materials for preparing the silicon tetrafluoride and hydrogen fluoride mixed gas is greatly expanded, the limitation that the fluosilicic acid concentration must be 18 percent in the Vanfu blue sky technology is overcome, all fluosilicic acid substances produced by wet-process phosphoric acid can be used for producing the silicon tetrafluoride and hydrogen fluoride mixed gas, and silicon tetrafluoride and hydrogen fluoride products can be obtained through simple separation.
(3) The right amount of water does not reduce the fluorine recovery rate, but rather makes the fluorine recovery rate higher because the reaction proceeds more easily.
Compared with the prior art for decomposing concentrated fluosilicic acid by concentrated sulfuric acid, the method has the following advantages:
(1) the use of the fluosilicic acid is not limited by the concentration limit value, and the range of raw materials is greatly widened.
(2) Fluosilicate (convenient for transportation and purchased from different places) can be used for replacing fluosilicic acid, so that the concentrated utilization of the associated fluorine resources of phosphorite can be realized, the large-scale gathering production is easy to realize, and a large base for efficiently utilizing the associated fluorine resources of phosphorite is extended.
(3) The use ratio of fluorine and sulfuric acid can be adjusted, the yield of the byproduct dilute sulfuric acid is reduced, the byproduct dilute sulfuric acid is sent to the phosphoric acid preparation process for reuse, the treatment of the byproduct is not required to be considered, and therefore the industrialization threshold of the technology is lowered.
(4) Two products of hydrogen fluoride and silicon tetrafluoride can be obtained, and the high-efficiency utilization of silicon resources is realized.
Compared with the prior art for decomposing sodium fluosilicate by concentrated sulfuric acid, the method has the following advantages:
(1) the sodium fluosilicate is replaced by part of fluosilicic acid, and the fluosilicic acid is not required to be completely prepared into the sodium fluosilicate, so that the manufacturing cost is reduced, and the consumption of concentrated sulfuric acid is reduced.
(2) The used salts such as sodium fluosilicate and the like do not need to be dried, the concentrated sulfuric acid dilution heat is used to the maximum extent in the process, a rotary kiln with low energy consumption utilization rate is not needed, the energy consumption is greatly reduced, and the cost is reduced.
(3) The system contains a certain amount of water, and the viscosity of the system is greatly reduced, so that common reaction equipment can be used, and industrial continuous and stable production is easy to realize.
In conclusion, the invention has the technical value of overcoming various defects of the prior art and comprehensively utilizing the fluorine-silicon resources in a high-efficiency and large-scale manner.
Drawings
FIG. 1 is a schematic block diagram of a method for preparing anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas by using phosphorus ore associated with fluorine according to an embodiment of the invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention are described in further detail below.
Example 1
Preparing 410g of 90wt% sodium fluosilicate (with the water content of 10%) and 540g of water into slurry, slowly adding 1360g of washing sulfuric acid (with the water content of 10%), reacting for 90min, and violently releasing heat of a system to obtain mixed gas of water-containing silicon tetrafluoride and hydrogen fluoride and fluorine-containing sulfuric acid; and (3) continuously carrying out defluorination on the fluorine-containing sulfuric acid at the temperature of 200 ℃ to obtain a mixed gas containing silicon tetrafluoride water and hydrogen fluoride, washing and dehydrating the mixed gas obtained in the two times through 1360g of hot concentrated sulfuric acid (98 wt%, 180 ℃) to obtain a mixed gas of anhydrous silicon tetrafluoride and hydrogen fluoride, and returning the washed sulfuric acid to the decomposition reaction.
In the process, the fluorine concentration of the fluorine-containing sulfuric acid is 0.28 percent, and the fluorine concentration after defluorination is 0.09 percent; the fluorine concentration of the washing sulfuric acid was 0.09%; the water content of the anhydrous silicon tetrafluoride-hydrogen fluoride mixed gas was 0.02%, the fluorine concentration (HF) was 26.2%, and the fluorine concentration (SiF)4) 52.8 percent; calculated as silicon dioxide (SiF)4Reduced to silica), silica content 41.3%. The fluorine recovery was 97.3%.
Example 2
Preparing 210g of 90wt% sodium fluosilicate (with the water content of 10%) and 1000g of 12wt% fluosilicic acid into slurry, slowly adding 2213g of washing sulfuric acid (with the water content of 10%), reacting for 60min, and violently releasing heat of the system to obtain mixed gas of water-containing silicon tetrafluoride and hydrogen fluoride and fluorine-containing sulfuric acid; and (3) continuously carrying out defluorination on the fluorine-containing sulfuric acid at 220 ℃ to obtain a mixed gas containing water silicon tetrafluoride and hydrogen fluoride, washing and dehydrating the mixed gas obtained in the two steps by 2250g of hot concentrated sulfuric acid (105 wt% and 190 ℃) to obtain a mixed gas of anhydrous silicon tetrafluoride and hydrogen fluoride, and returning the washed sulfuric acid to the decomposition reaction.
In the process, the fluorine concentration of the fluorine-containing sulfuric acid is 0.35 percent, and the fluorine concentration after defluorination is 0.11 percent; the fluorine concentration of the washing sulfuric acid is 0.07%; the water content of the anhydrous silicon tetrafluoride-hydrogen fluoride mixed gas was 0.05%, the fluorine concentration (HF) was 25.7%, and the fluorine concentration (SiF)4) 52.3 percent; calculated as silicon dioxide (SiF)4Reduced to silica), silica content 41.1%. The fluorine recovery was 98.4%.
Example 3
288g of 90wt% potassium fluosilicate (with the water content of 10%) and 1160g of 8wt% fluosilicic acid are mixed into slurry, 2692g of washing sulfuric acid (with the water content of 10%) is slowly added, the reaction lasts for 30min, and the system releases heat violently to obtain the mixed gas of the aqueous silicon tetrafluoride and the hydrogen fluoride and the fluorine-containing sulfuric acid; and (3) continuously carrying out defluorination on the fluorine-containing sulfuric acid at 160 ℃ to obtain a mixed gas containing water silicon tetrafluoride and hydrogen fluoride, washing and dehydrating the mixed gas obtained in the two times by 2700g of hot concentrated sulfuric acid (105 wt%, 220 ℃) to obtain a mixed gas of anhydrous silicon tetrafluoride and hydrogen fluoride, and returning the washed sulfuric acid to the decomposition reaction.
In the process, the fluorine concentration of the fluorine-containing sulfuric acid is 0.63 percent, and the fluorine concentration after defluorination is 0.13 percent; the fluorine concentration of the washing sulfuric acid is 0.05%; the water content of the anhydrous silicon tetrafluoride-hydrogen fluoride mixed gas was 0.12%, the fluorine concentration (HF) was 25.1%, and the fluorine concentration (SiF) was4) 51.6 percent; calculated as silicon dioxide (SiF)4Reduced to silica), silica content 40.5%. The fluorine recovery was 96.5%.
Example 4
Preparing 310g of 90wt% sodium fluosilicate (with the water content of 10%) and 424g of 16wt% fluosilicic acid into slurry, slowly adding 951g of washing sulfuric acid (with the weight content of 95%), reacting for 120min, and violently releasing heat of the system to obtain mixed gas of water-containing silicon tetrafluoride and hydrogen fluoride and fluorine-containing sulfuric acid; and (3) continuously carrying out defluorination on the fluorine-containing sulfuric acid at 220 ℃ to obtain a mixed gas containing water silicon tetrafluoride and hydrogen fluoride, washing and dehydrating the mixed gas obtained in the two times by 950g of hot concentrated sulfuric acid (98 wt%, 160 ℃) to obtain a mixed gas of anhydrous silicon tetrafluoride and hydrogen fluoride, and returning the washed sulfuric acid to the decomposition reaction.
In the process, the fluorine concentration of the fluorine-containing sulfuric acid is 0.43 percent, and the fluorine concentration after defluorination is 0.06 percent; the fluorine concentration of the washing sulfuric acid is 0.14%; the water content of the anhydrous silicon tetrafluoride-hydrogen fluoride mixed gas was 0.13%, the fluorine concentration (HF) was 25.9%, and the fluorine concentration (SiF)4) 52.5 percent; calculated as silicon dioxide (SiF)4Reduced to silica), silica content 41.7%. The fluorine recovery was 97.6%.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (10)
1. A method for preparing anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas by phosphorus ore associated fluorine is characterized by comprising the following steps:
(1) after uniformly stirring the water-containing fluosilicic acid, adding washing sulfuric acid for reaction to obtain a fluorine-containing sulfuric acid and a mixed gas of water-containing silicon tetrafluoride and hydrogen fluoride, wherein the washing sulfuric acid is obtained in step (3), the fluosilicic acid is selected from one or two of fluosilicic acid and fluosilicate, the mass ratio of water in the water-containing fluosilicic acid to the washing sulfuric acid is 1-3:7, and the content of fluorine in the water-containing fluosilicic acid is more than or equal to 24 wt%;
(2) heating the fluorine-containing sulfuric acid obtained in the step (1) at the temperature of 160-220 ℃ to obtain 70-80wt% of sulfuric acid and mixed gas of water-containing silicon tetrafluoride and hydrogen fluoride, wherein the 70-80wt% of sulfuric acid is used for preparing phosphoric acid;
(3) washing the mixed gas obtained in the step (1) and the step (2) by using hot concentrated sulfuric acid to obtain anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas, and sending the washed sulfuric acid to the step (1); the concentration of the hot concentrated sulfuric acid is 90-105wt%, and the temperature is 160-220 ℃.
2. The method for preparing anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas by using phosphorus ore associated with fluorine according to claim 1, wherein in step (1), the aqueous fluorosilicate is a mixture of fluorosilicate and water, a mixture of fluorosilicate and fluorosilicic acid or a mixture of fluorosilicate, fluorosilicic acid and water.
3. The method for preparing anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas by using phosphorus ore associated with fluorine according to claim 2, wherein the concentration of the fluosilicic acid is 2-25wt%, and the fluosilicate is an alkali metal fluosilicate or an alkaline earth metal fluosilicate.
4. The method for preparing anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas by using phosphorus ore associated fluorine according to claim 3, wherein the fluosilicic acid is a by-product fluosilicic acid of phosphoric acid; the fluosilicate is obtained by reacting a phosphoric acid byproduct, namely fluosilicic acid, and is dried or not dried.
5. The method for preparing anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas by using phosphorus ore associated with fluorine according to claim 3, wherein the fluorosilicate is selected from sodium fluorosilicate, potassium fluorosilicate, magnesium fluorosilicate or calcium fluorosilicate.
6. The method for preparing anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas by using phosphorus ore associated fluorine according to claim 1, wherein the aqueous fluosilicic acid product is a mixture of a fluosilicic acid byproduct of phosphoric acid and a fluorosilicate obtained by the reaction.
7. The method for preparing the anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas by the phosphorus ore associated with fluorine according to claim 1, wherein in the step (1), the reaction temperature is 70-160 ℃, and the heat is derived from the self-carrying heat and dilution heat of the washing sulfuric acid.
8. The method for preparing the anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas by the phosphorus ore associated with fluorine according to claim 1, wherein in the step (1), the reaction time is 30-120 min.
9. The method for preparing the anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas by the phosphorus ore associated with fluorine according to claim 1, wherein in the step (2), the heating time is 10-60 min.
10. The method for preparing the anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas by the phosphorus ore associated with fluorine according to claim 1, characterized by comprising the following steps:
(1) after uniformly stirring the water-containing fluosilicic acid, adding washing sulfuric acid for reaction for 30-120min to obtain a gas mixture of fluorine-containing sulfuric acid, water-containing silicon tetrafluoride and hydrogen fluoride, wherein the washing sulfuric acid is obtained in step (3), the water-containing fluosilicic acid is a mixture of a phosphoric acid by-product fluosilicic acid and a fluorosilicate obtained by reaction, the mass ratio of water in the water-containing fluosilicic acid to the washing sulfuric acid is 1-3:7, and the content of fluorine in the water-containing fluosilicic acid is more than or equal to 24 wt%;
(2) heating the fluorine-containing sulfuric acid obtained in the step (1) at the temperature of 160-;
(3) and (3) washing the mixed gas obtained in the step (1) and the step (2) by using hot concentrated sulfuric acid to obtain anhydrous silicon tetrafluoride and hydrogen fluoride mixed gas, and sending the washed sulfuric acid to the step (1), wherein the concentration of the hot concentrated sulfuric acid is 90-105wt%, and the temperature is 160-220 ℃.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114920202A (en) * | 2022-05-31 | 2022-08-19 | 江西天行化工有限责任公司 | Preparation method of hydrogen fluoride |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3257167A (en) * | 1961-10-02 | 1966-06-21 | Stauffer Chemical Co | Process for recovering strong hf from phosphate rock digestion processes |
| US3645680A (en) * | 1970-03-09 | 1972-02-29 | Wellman Lord Inc | Concentrating fluosilicic acid |
| CN1696050A (en) * | 2004-05-10 | 2005-11-16 | 四川大学 | Technique for preparing waterless hydrogen fluoride on high purity |
| CN107601434A (en) * | 2017-11-07 | 2018-01-19 | 衢州市鼎盛化工科技有限公司 | A kind of method and apparatus that hydrogen fluoride is prepared by fluosilicic acid |
-
2020
- 2020-09-27 CN CN202011029531.5A patent/CN112158850A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3257167A (en) * | 1961-10-02 | 1966-06-21 | Stauffer Chemical Co | Process for recovering strong hf from phosphate rock digestion processes |
| US3645680A (en) * | 1970-03-09 | 1972-02-29 | Wellman Lord Inc | Concentrating fluosilicic acid |
| CN1696050A (en) * | 2004-05-10 | 2005-11-16 | 四川大学 | Technique for preparing waterless hydrogen fluoride on high purity |
| CN107601434A (en) * | 2017-11-07 | 2018-01-19 | 衢州市鼎盛化工科技有限公司 | A kind of method and apparatus that hydrogen fluoride is prepared by fluosilicic acid |
Non-Patent Citations (1)
| Title |
|---|
| 管凌飞等: "我国磷矿伴生氟资源回收利用制无水氟化氢的发展现状及前景", 《有机氟工业》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114920202A (en) * | 2022-05-31 | 2022-08-19 | 江西天行化工有限责任公司 | Preparation method of hydrogen fluoride |
| CN114920202B (en) * | 2022-05-31 | 2023-06-06 | 江西天行化工有限责任公司 | Preparation method of hydrogen fluoride |
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