CN112320803B - Method for producing solid ammonium fluosilicate by using fluosilicic acid in phosphoric acid - Google Patents
Method for producing solid ammonium fluosilicate by using fluosilicic acid in phosphoric acid Download PDFInfo
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- C01B33/00—Silicon; Compounds thereof
- C01B33/08—Compounds containing halogen
- C01B33/10—Compounds containing silicon, fluorine, and other elements
- C01B33/103—Fluosilicic acid; Salts thereof
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Abstract
The invention belongs to the technical field of chemical industry, and particularly relates to a method for producing solid ammonium fluosilicate by utilizing fluosilicic acid in phosphoric acid. The invention adopts a precipitation method to separate SiF6 2‑Medium defluorination, low energy consumption and high recovery rate which reaches more than 95 percent; the invention adopts acidolysis of potassium fluosilicate to volatilize and separate SiF4、HF，SiF4Introducing HF mixed gas into a saturated ammonium fluosilicate solution to carry out amination to prepare ammonium fluosilicate, which is beneficial to preparing high-purity ammonium fluosilicate, and finally obtaining solid ammonium fluosilicate with higher purity of more than 99.5 percent; the invention fully recycles each product, adopts the precipitation method to separate fluorine, is easy to control the water balance of the whole process system, and solves the problem of generating a large amount of wastewater.
Description
Technical Field
The invention belongs to the technical field of chemical industry, and particularly relates to a method for producing solid ammonium fluosilicate by utilizing fluosilicic acid in phosphoric acid.
Background
Phosphoric acid is an intermediate product for producing ammonium phosphate, triple superphosphate and various phosphate products, and is an indispensable raw material in the industries of metallurgy, petroleum, chemical industry, electronics, medicine, food and the like. The purity of the starting phosphoric acid determines the purity and use of the individual phosphates in the subsequent product chain.
At present, phosphoric acid can be prepared by a wet method, the content of fluorine in the wet-method phosphoric acid is high, the use requirement is difficult to meet, and the fluorine in the phosphoric acid needs to be removed by a defluorination process, but the existing defluorination process has the following problems: (1) the defluorination efficiency is not high; (2) the consumption of phosphoric acid is large: at present, the domestic wet-process defluorination purification of concentrated phosphoric acid adopts more chemical precipitation defluorination, the chemical precipitation defluorination is realized by utilizing sodium hydroxide and fluosilicic acid to generate sodium fluosilicate, and the low solubility of the sodium fluosilicate in the phosphoric acid is utilized to cause the consumption of the phosphoric acid.
Although there is a method for preparing ammonium fluosilicate by using tail gas containing fluorine in phosphate fertilizer production, the method is directed at the procedures of phosphorite acidification in calcium phosphate production, phosphoric acid extraction in wet-process phosphoric acid production, phosphoric acid concentration and the like, the generated tail gas containing fluorine (SiF4+ HF) is collected and utilized, and the tail gas containing fluorine can only be used in the generated tail gas containing fluorine, and no good treatment method is provided for fluorine dissolved in phosphoric acid.
However, the fluorine element in the fluorine-containing phosphoric acid is not fully utilized in the existing phosphoric acid defluorination process, and a large amount of water is needed, so that a large amount of waste water is generated, for example, a wet-process phosphoric acid defluorination method of patent application CN201910893988.1 needs a large amount of steam, and the final product is sodium fluosilicate, so that high-purity ammonium fluosilicate cannot be obtained; or by chemical precipitation defluorination, for example, the defluorination method of wet-process phosphoric acid disclosed in patent application CN201911399698.8, which utilizes alkali metal salts or alkaline earth metal salts, including but not limited to sodium chloride, sodium sulfate, potassium sulfate, sodium carbonate, calcium chloride, calcium carbonate, potassium chloride, and 1:1 mixture of sodium chloride and potassium chloride, to perform precipitation defluorination, and utilizes the low solubility of fluorosilicate in phosphoric acid, which also results in phosphoric acid consumption.
At present, no method for producing solid ammonium fluosilicate by directly utilizing fluosilicic acid in phosphoric acid exists.
Therefore, it is urgent to find a method which can produce solid ammonium fluorosilicate by using fluosilicic acid in phosphoric acid, has good defluorination effect, high fluorine recovery rate, high purity of the obtained solid ammonium fluorosilicate, achieves water balance circulation in the whole process, can repeatedly use defluorination agent and hardly generates wastewater.
Disclosure of Invention
In order to solve the technical problems in the prior art, the invention provides a method for producing solid ammonium fluosilicate by using fluosilicic acid in phosphoric acid, which is realized by the following technical scheme:
a method for producing solid ammonium fluosilicate by utilizing fluosilicic acid in phosphoric acid is characterized by comprising the following steps:
(1) adding potassium sulfate into fluorine-containing phosphoric acid, aging, precipitating after aging, separating solid and liquid, and collecting respectively, wherein the liquid phase is defluorinated phosphoric acid and the solid phase is potassium fluosilicate;
(2) adding concentrated sulfuric acid into the solid-phase potassium fluosilicate obtained in the step (1), heating for reaction, and separating and collecting gas and reaction slag;
(3) introducing the gas separated and collected in the step (2) into saturated ammonium fluosilicate solution, and then adding NH into the saturated ammonium fluosilicate solution3Or NH4HCO3Controlling the pH value of the solution to be 2-3, and aging in a thickener;
(4) and (4) centrifugally dewatering the aged solution obtained in the step (3), drying the solid product to obtain solid ammonium fluosilicate, wherein the liquid is a saturated ammonium fluosilicate solution.
Preferably, the fluorine-containing phosphoric acid contains 0.5-5% of fluosilicic acid.
Preferably, the aging is carried out for an actual aging time of 30 min.
Preferably, the concentrated sulfuric acid has a concentration of 98%.
Preferably, the heating reaction in the step (2) is heating at 120-180 ℃ for 10-30min under normal pressure.
Preferably, the potassium sulfate reaction slag in the step (2) is collected and recycled to the step (1).
Preferably, the saturated ammonium fluorosilicate solution obtained in the step (4) is recycled to the step (3).
Compared with the prior art, the invention has the technical effects that:
(1) the invention adopts a precipitation method to separate SiF from phosphoric acid6 2-The separation process is simple, the energy consumption is low, and the recovery rate is high and reaches more than 95%.
(2) The invention adopts acidolysis of potassium fluosilicate to volatilize and separate SiF4And HF, so that ammonium fluosilicate is prepared, the preparation of high-purity ammonium fluosilicate is facilitated, and the purity of the finally obtained solid ammonium fluosilicate is higher and is more than 99.5%.
(3) The invention fully recycles each product, reduces the production cost, adopts the precipitation method to separate fluorine, is easy to control the water balance of the whole process system, and solves the problem of generating a large amount of waste water.
(4) The invention fully recycles the defluorinating agent potassium sulfate, reduces the production cost, generates no waste, and solves the problem that the prior chemical precipitation method defluorinates to generate a large amount of waste.
Detailed Description
The technical solution of the present invention is further defined below with reference to the specific embodiments, but the scope of the claims is not limited to the description.
Example 1
(1) Adding 175.8g of potassium sulfate into 5760g of fluorine-containing phosphoric acid, then aging for 30min, precipitating after the aging is finished, separating solid from liquid, and respectively collecting, wherein the liquid phase is defluorinated phosphoric acid, and the solid phase is potassium fluosilicate;
(2) adding 100g of 98% concentrated sulfuric acid into the solid-phase potassium fluosilicate obtained in the step (1), heating at 150 ℃ for 20min under normal pressure, separating and collecting gas and potassium sulfate reaction slag, collecting the potassium sulfate reaction slag, and recycling the potassium sulfate reaction slag into the step (1);
(3) introducing the gas separated and collected in the step (2) into saturated ammonium fluosilicate solution, and adding NH into the saturated ammonium fluosilicate solution3The mass is 34g, the pH value of the solution is controlled to be 2.5, and the solution is aged in a thickener;
(4) and (4) centrifugally dewatering the aged solution obtained in the step (3), drying the solid product to obtain solid ammonium fluosilicate, wherein the liquid is a saturated ammonium fluosilicate solution, and recycling the obtained saturated ammonium fluosilicate solution into the step (3).
The fluorine-containing phosphoric acid contains 2.5% of fluosilicic acid.
Example 2
(1) Adding 175.8g of potassium sulfate into 5760g of fluorine-containing phosphoric acid, then aging for 30min, precipitating after the aging is finished, separating solid from liquid, and respectively collecting, wherein the liquid phase is defluorinated phosphoric acid, and the solid phase is potassium fluosilicate;
(2) adding 100g of 98% concentrated sulfuric acid into the solid-phase potassium fluosilicate obtained in the step (1), heating at 120 ℃ for 30min under normal pressure, separating and collecting gas and potassium sulfate reaction slag, collecting the potassium sulfate reaction slag, and recycling the potassium sulfate reaction slag into the step (1);
(3) introducing the gas separated and collected in the step (2) into saturated ammonium fluosilicate solution, and adding NH into the saturated ammonium fluosilicate solution3The mass is 34g, the pH value of the solution is controlled to be 2, and the solution is aged in a thickener;
(4) and (4) centrifugally dewatering the aged solution obtained in the step (3), drying the solid product to obtain solid ammonium fluosilicate, wherein the liquid is a saturated ammonium fluosilicate solution, and recycling the obtained saturated ammonium fluosilicate solution into the step (3).
The fluorine-containing phosphoric acid contains 2.5% of fluosilicic acid.
Example 3
(1) Adding 175.8g of potassium sulfate into 5760g of fluorine-containing phosphoric acid, then aging for 30min, precipitating after the aging is finished, separating solid from liquid, and respectively collecting, wherein the liquid phase is defluorinated phosphoric acid, and the solid phase is potassium fluosilicate;
(2) adding 100g of 98% concentrated sulfuric acid into the solid-phase potassium fluosilicate obtained in the step (1), heating at the normal pressure of 180 ℃ for 10min, separating and collecting gas and potassium sulfate reaction slag, collecting the potassium sulfate reaction slag, and recycling the potassium sulfate reaction slag into the step (1);
(3) introducing the gas separated and collected in the step (2) into saturated ammonium fluosilicate solution, and then adding NH into the saturated ammonium fluosilicate solution4HCO3The mass is 158g, the pH value of the solution is controlled to be 3, and the solution is aged in a thickener;
(4) and (4) performing centrifugal dehydration on the solution aged in the step (3), drying the solid product to obtain solid ammonium fluosilicate, wherein the liquid is saturated ammonium fluosilicate solution, and recycling the obtained saturated ammonium fluosilicate solution to the step (3).
The fluorine-containing phosphoric acid contains 2.5% of fluosilicic acid.
Example 4
(1) Adding 175.8g of potassium sulfate into 28800g of fluorine-containing phosphoric acid, then aging for 30min, precipitating after the aging is finished, separating solid from liquid, and respectively collecting, wherein the liquid phase is defluorinated phosphoric acid, and the solid phase is potassium fluosilicate;
(2) adding 100g of 98% concentrated sulfuric acid into the solid-phase potassium fluosilicate obtained in the step (1), heating at 150 ℃ for 20min under normal pressure, separating and collecting gas and potassium sulfate reaction slag, collecting the potassium sulfate reaction slag, and recycling the potassium sulfate reaction slag into the step (1);
(3) introducing the gas separated and collected in the step (2) into saturated ammonium fluosilicate solution, and adding NH into the saturated ammonium fluosilicate solution3The mass of (2) is 34g, the pH value of the solution is controlled to be 2.5, and the solution is aged in a thickener;
(4) and (4) centrifugally dewatering the aged solution obtained in the step (3), drying the solid product to obtain solid ammonium fluosilicate, wherein the liquid is a saturated ammonium fluosilicate solution, and recycling the obtained saturated ammonium fluosilicate solution into the step (3).
The fluorine-containing phosphoric acid contains 0.5% of fluosilicic acid.
Example 5
(1) Adding 175.8g of potassium sulfate into 2880g of fluorine-containing phosphoric acid, then aging for 30min, precipitating after the aging is finished, separating solid from liquid, and respectively collecting, wherein the liquid phase is defluorinated phosphoric acid, and the solid phase is potassium fluosilicate;
(2) adding 100g of 98% concentrated sulfuric acid into the solid-phase potassium fluosilicate obtained in the step (1), heating at 150 ℃ for 20min under normal pressure, separating and collecting gas and potassium sulfate reaction slag, collecting and recycling the potassium sulfate reaction slag into the step (1);
(3) introducing the gas separated and collected in the step (2) into saturated ammonium fluosilicate solution, and adding NH into the saturated ammonium fluosilicate solution3The mass of (2) is 34g, the pH value of the solution is controlled to be 2.5, and the solution is aged in a thickener;
(4) and (4) centrifugally dewatering the aged solution obtained in the step (3), drying the solid product to obtain solid ammonium fluosilicate, wherein the liquid is a saturated ammonium fluosilicate solution, and recycling the obtained saturated ammonium fluosilicate solution into the step (3).
The fluorine-containing phosphoric acid contains 5% of fluosilicic acid.
Example 6
(1) Adding 175.8g of potassium sulfate into 5760g of fluorine-containing phosphoric acid, then aging for 30min, precipitating after the aging is finished, separating solid from liquid, and collecting respectively, wherein the liquid phase is defluorinated phosphoric acid, and the solid phase is potassium fluosilicate;
(2) adding 100g of 98% concentrated sulfuric acid into the solid-phase potassium fluosilicate obtained in the step (1), heating at 150 ℃ for 20min under normal pressure, separating and collecting gas and potassium sulfate reaction slag, collecting the potassium sulfate reaction slag, and recycling the potassium sulfate reaction slag into the step (1);
(3) introducing the gas separated and collected in the step (2) into saturated ammonium fluosilicate solution, and adding NH into the saturated ammonium fluosilicate solution4HCO3The mass of (2) was 158g, the pH of the solution was controlled to 2.5, and the solution was aged in a thickener；
(4) And (4) centrifugally dewatering the aged solution obtained in the step (3), drying the solid product to obtain solid ammonium fluosilicate, wherein the liquid is a saturated ammonium fluosilicate solution, and recycling the obtained saturated ammonium fluosilicate solution into the step (3).
The fluorine-containing phosphoric acid contains 2.5% of fluosilicic acid.
Comparative example 1
The process was carried out according to patent application CN201911399698.8, example 5 of a defluorination process for wet phosphoric acid, using a fluosilicic acid content of 2.5% in the fluorine-containing phosphoric acid.
Comparative example 2
(1) Adding 175.8g of potassium sulfate into 5760g of fluorine-containing phosphoric acid, then aging for 30min, precipitating after the aging is finished, separating solid from liquid, and respectively collecting, wherein the liquid phase is defluorinated phosphoric acid, and the solid phase is potassium fluosilicate;
(2) adding 100g of 98% concentrated sulfuric acid into the solid-phase potassium fluosilicate obtained in the step (1), heating at 150 ℃ for 20min under normal pressure, separating and collecting gas and potassium sulfate reaction slag, collecting the potassium sulfate reaction slag, and recycling the potassium sulfate reaction slag into the step (1);
(3) and (3) treating the gas separated and collected in the step (2) according to patent CN201010200763.2, wherein the treatment is carried out according to example 1 of the method for preparing ammonium fluosilicate by using tail gas containing fluorine in phosphate fertilizer production.
The fluorine-containing phosphoric acid contains 2.5% of fluosilicic acid.
The results of examples 1-6 and comparative examples 1-2 were examined and recorded as follows:
finally, it should be noted that the above embodiments are merely representative examples of the present invention. Obviously, the technical solution of the present invention is not limited to the above-described embodiments, and many variations are possible. All modifications which can be derived or suggested by a person skilled in the art from the disclosure of the present invention are to be considered within the scope of the invention.
Claims (4)
1. A method for producing solid ammonium fluosilicate by utilizing fluosilicic acid in phosphoric acid is characterized by comprising the following steps:
(1) adding potassium sulfate into fluorine-containing phosphoric acid, aging, precipitating after aging, separating solid and liquid, and collecting respectively, wherein the liquid phase is defluorinated phosphoric acid and the solid phase is potassium fluosilicate;
(2) adding concentrated sulfuric acid into the solid-phase potassium fluosilicate obtained in the step (1), heating for reaction, separating and collecting gas and reaction slag, collecting and recycling the potassium sulfate reaction slag into the step (1), wherein the heating for reaction is heating for 10-30min at the temperature of 120-180 ℃ under normal pressure;
(3) introducing the gas separated and collected in the step (2) into saturated ammonium fluosilicate solution, and adding NH into the saturated ammonium fluosilicate solution3Or NH4HCO3Controlling the pH =2-3 of the solution, and aging in a thickener;
(4) and (4) centrifugally dewatering the aged solution obtained in the step (3), drying the solid product to obtain solid ammonium fluosilicate, wherein the liquid is a saturated ammonium fluosilicate solution, and recycling the obtained saturated ammonium fluosilicate solution into the step (3).
2. A method for producing solid ammonium fluosilicate by utilizing fluosilicic acid in phosphoric acid as claimed in claim 1, wherein the content of the fluosilicic acid in the fluorine-containing phosphoric acid is 0.5-5%.
3. The method for producing solid ammonium fluorosilicate by utilizing fluosilicic acid in phosphoric acid as set forth in claim 1 or 2, wherein the aging is carried out for an actual aging time of 30 min.
4. The method for producing solid ammonium fluosilicate by using fluosilicic acid in phosphoric acid according to claim 1 or 2, wherein the concentrated sulfuric acid has a concentration of 98%.
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| CN114715904B (en) * | 2022-02-24 | 2023-06-23 | 深圳市环保科技集团股份有限公司 | Cooperative treatment method for CVD dust and ammonium chloride waste liquid |
| CN115124019B (en) * | 2022-06-15 | 2024-05-28 | 湖北大学 | Method for preparing silicon-carbon material by utilizing fluosilicic acid waste |
| CN115626647A (en) * | 2022-10-18 | 2023-01-20 | 宜都兴发化工有限公司 | Method for preparing potassium fluosilicate from fluorine-containing liquid |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4046860A (en) * | 1973-05-14 | 1977-09-06 | Kidde Gustave E | Ammonium fluoride process for defluorinating phosphoric acids and production of ammonium fluosilicate |
| US4981664A (en) * | 1988-04-14 | 1991-01-01 | International Minerals & Chemical Corporation | Method of production of high purity silica and ammonium fluoride |
| CN101708832A (en) * | 2009-11-02 | 2010-05-19 | 山东红日阿康化工股份有限公司 | Method for producing defluorinated ammonium phosphate |
| CN101717290A (en) * | 2009-11-02 | 2010-06-02 | 山东红日阿康化工股份有限公司 | Method for producing defluorinated sulfenyl nitrogen-phosphorus-potassium compound fertilizer |
| CN101850978A (en) * | 2010-06-06 | 2010-10-06 | 程建方 | Method for preparing ammonium fluosilicate by utilizing tail gas containing fluorine in phosphatic fertilizer production |
| CN102951611A (en) * | 2012-12-24 | 2013-03-06 | 贵州省化工研究院 | Method for preparing anhydrous hydrogen fluoride by utilizing fluorine-containing waste liquid or fluorosilicic acid in phosphate fertilizer enterprises |
-
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- 2020-10-27 CN CN202011165476.2A patent/CN112320803B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4046860A (en) * | 1973-05-14 | 1977-09-06 | Kidde Gustave E | Ammonium fluoride process for defluorinating phosphoric acids and production of ammonium fluosilicate |
| US4981664A (en) * | 1988-04-14 | 1991-01-01 | International Minerals & Chemical Corporation | Method of production of high purity silica and ammonium fluoride |
| CN101708832A (en) * | 2009-11-02 | 2010-05-19 | 山东红日阿康化工股份有限公司 | Method for producing defluorinated ammonium phosphate |
| CN101717290A (en) * | 2009-11-02 | 2010-06-02 | 山东红日阿康化工股份有限公司 | Method for producing defluorinated sulfenyl nitrogen-phosphorus-potassium compound fertilizer |
| CN101850978A (en) * | 2010-06-06 | 2010-10-06 | 程建方 | Method for preparing ammonium fluosilicate by utilizing tail gas containing fluorine in phosphatic fertilizer production |
| CN102951611A (en) * | 2012-12-24 | 2013-03-06 | 贵州省化工研究院 | Method for preparing anhydrous hydrogen fluoride by utilizing fluorine-containing waste liquid or fluorosilicic acid in phosphate fertilizer enterprises |
Non-Patent Citations (2)
| Title |
|---|
| Further investigation on the formation mechanisms of (NH4)(2)SiF6 synthesized by dry etching technique;Kabacelik, I;《APPLIED SURFACE SCIENCE》;20070824;第254卷(第6期);第1870-1873页 * |
| 利用磷肥企业氟化物生产固体氟硅酸铵的方法;唐波;《无机盐工业》;20151031;第47卷(第10期);第294页 * |
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