CN112607708B - Hydrogen fluoride gas treatment process - Google Patents
Hydrogen fluoride gas treatment process Download PDFInfo
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- CN112607708B CN112607708B CN202011533873.0A CN202011533873A CN112607708B CN 112607708 B CN112607708 B CN 112607708B CN 202011533873 A CN202011533873 A CN 202011533873A CN 112607708 B CN112607708 B CN 112607708B
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B7/00—Halogens; Halogen acids
- C01B7/19—Fluorine; Hydrogen fluoride
- C01B7/191—Hydrogen fluoride
- C01B7/195—Separation; Purification
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B7/00—Halogens; Halogen acids
- C01B7/19—Fluorine; Hydrogen fluoride
- C01B7/191—Hydrogen fluoride
- C01B7/195—Separation; Purification
- C01B7/196—Separation; Purification by distillation
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B7/00—Halogens; Halogen acids
- C01B7/19—Fluorine; Hydrogen fluoride
- C01B7/191—Hydrogen fluoride
- C01B7/195—Separation; Purification
- C01B7/197—Separation; Purification by adsorption
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- Inorganic Chemistry (AREA)
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Abstract
The invention discloses a hydrogen fluoride gas treatment process, which comprises the following steps: s1, preparing fluosilicic acid and silicon dioxide; s2, preparing hydrogen fluoride gas for the first-stage treatment; s3, preparing hydrogen fluoride gas for secondary treatment; s4, preparing hydrogen fluoride gas of the third-stage treatment, and S5, preparing hydrogen fluoride gas of the fourth-stage treatment; s6, preparing high-purity anhydrous hydrogen fluoride gas; the invention has the beneficial effects that: 1 through adopting concentrated sulfuric acid to carry out the dehydration of hydrogen fluoride gas and the acidity regulation of silicon tetrafluoride gas, pass through the molecular rectification again, separate sulphuric acid molecule and hydrogen fluoride, adopt water or rare fluosilicic acid to impurity gas to absorb simultaneously, the hydrogen fluoride after the processing lets in proper order among the microchannel apparatus after the wall modification treatment, handle in the spherical desicator that contains the molecular sieve again, thereby realize the abundant absorption of impurity in the hydrogen fluoride gas in the microchannel apparatus, and the abundant absorption of impurity such as steam in the course of working, and then realize abundant absorptive purpose.
Description
Technical Field
The invention relates to the technical field of hydrogen fluoride treatment, in particular to a hydrogen fluoride gas treatment process.
Background
There can be a large amount of fluorine-containing waste gas to escape in phosphate fertilizer production process in a large amount of fluorine-containing waste gas, and direct emission will cause the pollution and bring the loss of resource for the atmosphere, and along with the improvement of environmental protection requirement and the shortage of resource, many enterprises begin to regard the recovery and the utilization to fluorine-containing gas. In phosphate fertilizer plants, fluorine-containing gas is generally absorbed by water to produce fluosilicic acid, and the chemical equation is as follows:
3SiF4+ 4H2O→2H2SiF6+SiO2·2H2O↓
SF4+ 2HF→H2SiF6
in general, phosphate fertilizer enterprises process the obtained fluorosilicic acid solution into fluorosilicate, fluoride and the like, and the processing into hydrogen fluoride is less at present. Meanwhile, silicon tetrafluoride gas is doped while hydrogen fluoride is generated, so that the concentration of hydrogen fluoride gas is influenced, which is one of the reasons for restricting the yield of hydrogen fluoride. Most of the existing hydrogen fluoride absorption adopts water solution to absorb and convert into hydrofluoric acid, and then the hydrofluoric acid is used as a chemical raw material, but the existing industrial hydrogen fluoride contains various impurities, especially silicon tetrafluoride gas, and silicon dioxide particles precipitate or a silica gel solution can be generated in the absorption stage to hinder the hydrogen fluoride gas absorption, and meanwhile, the silicon dioxide particles are easy to stack in the equipment to block the equipment, so that how to remove the silicon tetrafluoride gas and prevent the blockage of the silicon dioxide impurities is one of the problems to be solved urgently in the existing hydrogen fluoride absorption stage.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a hydrogen fluoride gas treatment process so as to at least achieve the aim of fully absorbing impurities.
The purpose of the invention is realized by the following technical scheme:
a hydrogen fluoride gas treatment process comprises the following steps:
s1, introducing hydrogen fluoride gas containing silicon tetrafluoride to be treated into a concentrated sulfuric acid solution, collecting the obtained sulfuric acid solution containing hydrogen fluoride by utilizing different molecular polarities, and absorbing escaped silicon tetrafluoride gas by water or dilute fluosilicic acid to obtain fluosilicic acid and silicon dioxide;
s2, carrying out molecular rectification on concentrated sulfuric acid containing hydrogen fluoride, and collecting to obtain hydrogen fluoride gas subjected to first-stage treatment;
s3, introducing the hydrogen fluoride gas subjected to the first-stage treatment into the microchannel equipment, and simultaneously performing modified cross-linked polyethylene glycol treatment on the wall surface of the microchannel equipment to obtain the hydrogen fluoride gas subjected to the second-stage treatment;
s4, introducing the obtained hydrogen fluoride gas subjected to the second-stage treatment into microchannel equipment, and treating the hydrogen fluoride gas subjected to the third-stage treatment by using modified dimethyl polysilane or phenyl polysilane on the wall surface of the microchannel equipment;
s5, introducing the hydrogen fluoride gas subjected to the third-stage treatment into a drying tower containing granular activated carbon to obtain a hydrogen fluoride gas subjected to the fourth-stage treatment;
s6, introducing the hydrogen fluoride gas subjected to the fourth-stage treatment into a spherical dryer containing a molecular sieve to obtain a high-purity anhydrous hydrogen fluoride gas product.
Preferably, for the purpose of further achieving sufficient impurity absorption, the microchannel device is selected from one or more of a side-port addition type microchannel device (application number CN 201822155379), a wiped film type rotating microchannel device (application number CN 201822153471), an extended wiped film type rotating microchannel device (application number CN 201822159540) and a rotating microchannel device (application number CN 201922326497) for demulsification; the modification treatment is that the wall surface in the microchannel equipment is coated with modified cross-linked polyethylene glycol, dimethyl polysilane or phenyl polysilane to form a layer of uniform protective film; through designing multiple microchannel equipment, adopt the coating of modified crosslinked polyethylene glycol, dimethyl polysilane or phenyl polysilane simultaneously on the inner wall to microchannel equipment, and then realize utilizing microchannel equipment to carry out the absorption of the gaseous impurity of silicon tetrafluoride in the hydrogen fluoride gas to realize the gaseous absorption of silicon tetrafluoride, and then realize the purpose of fully absorbing impurity.
Preferably, for the purpose of further achieving the purpose of fully absorbing impurities, the molecular sieve is a 4A molecular sieve; residual water vapor in the hydrogen fluoride gas is absorbed by adopting the 4A molecular sieve, so that pure hydrogen fluoride gas is obtained.
The invention has the beneficial effects that:
1. through adopting concentrated sulfuric acid to carry out the dehydration of hydrogen fluoride gas and the acidity regulation of silicon tetrafluoride gas, through the molecular rectification, separate sulphuric acid molecule and hydrogen fluoride, adopt water or rare fluosilicic acid to absorb impurity gas simultaneously, hydrogen fluoride after the processing lets in the microchannel apparatus after the wall modification treatment in proper order, handle in the spherical desicator that contains the molecular sieve again, thereby realize the abundant absorption of impurity in the hydrogen fluoride gas in the microchannel apparatus, and the abundant absorption of impurity such as steam in the course of treatment, and then realize abundant absorptive purpose.
2. Through designing multiple microchannel equipment, adopt the coating of modified crosslinked polyethylene glycol, dimethyl polysilane or phenyl polysilane simultaneously on the inner wall to microchannel equipment, and then realize utilizing microchannel equipment to carry out the absorption of the gaseous impurity of silicon tetrafluoride in the hydrogen fluoride gas to realize the gaseous absorption of silicon tetrafluoride, and then realize the purpose of fully absorbing impurity.
3. Residual water vapor in the hydrogen fluoride gas is absorbed by adopting the 4A molecular sieve, so that pure hydrogen fluoride gas is obtained.
Detailed Description
The technical solutions of the present invention are described in further detail below, but the scope of the present invention is not limited to the following.
Example 1
A hydrogen fluoride gas treatment process comprises the following steps:
s1, introducing hydrogen fluoride gas containing silicon tetrafluoride to be treated into a concentrated sulfuric acid solution, collecting the obtained sulfuric acid solution containing hydrogen fluoride by utilizing different molecular polarities, and absorbing the escaped silicon tetrafluoride gas by dilute fluosilicic acid to obtain fluosilicic acid and silicon dioxide;
s2, carrying out molecular rectification on concentrated sulfuric acid containing hydrogen fluoride, and collecting to obtain hydrogen fluoride gas subjected to first-stage treatment;
s3, introducing the hydrogen fluoride gas subjected to the first-stage treatment into the microchannel equipment, and simultaneously performing modified cross-linked polyethylene glycol treatment on the wall surface of the microchannel equipment to obtain the hydrogen fluoride gas subjected to the second-stage treatment;
s4, introducing the obtained hydrogen fluoride gas subjected to the second-stage treatment into microchannel equipment, and simultaneously performing modified dimethyl polysilane treatment on the wall surface of the microchannel equipment to obtain a hydrogen fluoride gas subjected to third-stage treatment;
s5, introducing the hydrogen fluoride gas subjected to the third-stage treatment into a drying tower containing granular activated carbon to obtain a hydrogen fluoride gas subjected to the fourth-stage treatment;
s6, introducing the hydrogen fluoride gas subjected to the fourth-stage treatment into a spherical dryer containing a molecular sieve to obtain a high-purity anhydrous hydrogen fluoride gas product.
In order to further realize the purpose of fully absorbing impurities, the microchannel equipment is side-port-added microchannel equipment (application number CN 201822155379); the modification treatment is that the wall surface in the microchannel equipment is coated with modified cross-linked polyethylene glycol, dimethyl polysilane or phenyl polysilane to form a layer of uniform protective film; through designing multiple microchannel equipment, adopt the coating of modified crosslinked polyethylene glycol, dimethyl polysilane or phenyl polysilane simultaneously on the inner wall to microchannel equipment, and then realize utilizing microchannel equipment to carry out the absorption of the gaseous impurity of silicon tetrafluoride in the hydrogen fluoride gas to realize the gaseous absorption of silicon tetrafluoride, and then realize the purpose of fully absorbing impurity.
In order to further achieve the purpose of fully absorbing impurities and further achieve the purpose of fully absorbing impurities, the molecular sieve is a 4A molecular sieve; residual water vapor in the hydrogen fluoride gas is absorbed by adopting the 4A molecular sieve, so that pure hydrogen fluoride gas is obtained.
Example 2
The channel equipment is a wiped film type rotating micro-channel equipment (application number CN 201822153471), simultaneously, the escaped silicon tetrafluoride gas is absorbed by water, modified dimethyl polysilane treatment is carried out on the wall surface of the micro-channel equipment in S4, and the rest steps and the formula are the same as those in example 1.
Example 3
The channel equipment is lengthened, wiped film type rotating microchannel equipment (application number CN 201822159540) is selected, meanwhile, escaped silicon tetrafluoride gas is absorbed by dilute fluosilicic acid, modified phenyl polysilane treatment is carried out on the wall surface of the microchannel equipment in S4, and other steps and the formula are the same as those in example 1.
Example 4
The channel equipment is selected from demulsifying rotary micro-channel equipment (application number CN 201922326497), simultaneously, the escaped silicon tetrafluoride gas is absorbed by water, and the wall surface of the micro-channel equipment is treated by modified phenyl polysilane in S4, and the rest steps and the formula are the same as those in example 1.
Example 5
The channel equipment is added into the microchannel equipment with a side port (application number CN 201822155379), simultaneously, the escaped silicon tetrafluoride gas is absorbed by dilute fluosilicic acid, modified dimethyl polysilane treatment is carried out on the wall surface of the microchannel equipment in S4, and other steps and the formula are the same as those in example 1.
Example 6
The method comprises the steps of selecting a side port adding type microchannel device (application number CN 201822155379), a wiped film type rotating microchannel device (application number CN 201822153471), a lengthened wiped film type rotating microchannel device (application number CN 201822159540) and a rotating microchannel device (application number CN 201922326497) for demulsification, absorbing escaped silicon tetrafluoride gas by dilute fluosilicic acid, treating dimethyl polysilane modified on the wall surface of the microchannel device in S4, and performing the rest steps and the formula in the same way as in example 1.
Comparative example 1
The microchannel apparatus was used without modification, and the other steps and formulation were the same as in example 1.
Comparative example 2
The microchannel equipment is not adopted, a U-shaped pipeline is directly adopted, and the rest steps and the formula are the same as those in the example 1.
The loss ratio of hydrogen fluoride, the weight gain ratio of silica particles in the microchannel apparatus, and the product purity in each of the examples and comparative examples were counted to obtain Table 1.
TABLE 1 tables of the hydrogen fluoride loss ratio, silica weight gain ratio and product purity of each example and comparative example
As shown in table 1, when the microchannel apparatus is a side-port-loading microchannel apparatus (application No. CN 201822155379), and the escaped silicon tetrafluoride gas is absorbed by dilute fluorosilicic acid, the wall of the microchannel apparatus is treated with the modified dimethylpolysiloxane in S4, and the absorbed hydrogen fluoride has a hydrogen fluoride loss ratio of 10.6%, a silicon dioxide weight gain ratio of 0.3%, and a hydrogen fluoride purity of 99.95%, which illustrates the advantages of the present invention.
The foregoing is illustrative of the preferred embodiments of this invention, and it is to be understood that the invention is not limited to the precise form disclosed herein and that various other combinations, modifications, and environments may be resorted to, falling within the scope of the concept as disclosed herein, either as described above or as apparent to those skilled in the relevant art. And that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (4)
1. A hydrogen fluoride gas treatment process is characterized in that: the method comprises the following steps:
s1, introducing hydrogen fluoride gas containing silicon tetrafluoride to be treated into a concentrated sulfuric acid solution, collecting the obtained sulfuric acid solution containing hydrogen fluoride by utilizing different molecular polarities, and absorbing escaped silicon tetrafluoride gas by water or dilute fluosilicic acid to obtain fluosilicic acid and silicon dioxide;
s2, carrying out molecular rectification on concentrated sulfuric acid containing hydrogen fluoride, and collecting to obtain hydrogen fluoride gas subjected to first-stage treatment;
s3, introducing the hydrogen fluoride gas subjected to the first-stage treatment into the microchannel equipment, and simultaneously performing modified cross-linked polyethylene glycol treatment on the wall surface of the microchannel equipment to obtain the hydrogen fluoride gas subjected to the second-stage treatment;
s4, introducing the obtained hydrogen fluoride gas subjected to the second-stage treatment into microchannel equipment, and treating the hydrogen fluoride gas subjected to the third-stage treatment by using modified dimethyl polysilane or phenyl polysilane on the wall surface of the microchannel equipment;
s5, introducing the hydrogen fluoride gas subjected to the third-stage treatment into a drying tower containing granular activated carbon to obtain a hydrogen fluoride gas subjected to the fourth-stage treatment;
s6, introducing the hydrogen fluoride gas subjected to the fourth-stage treatment into a spherical dryer containing a molecular sieve to obtain a high-purity anhydrous hydrogen fluoride gas product.
2. The hydrogen fluoride gas treatment process according to claim 1, wherein: the microchannel equipment is one or more of side-port adding type microchannel equipment, wiped film type rotating microchannel equipment, lengthened wiped film type rotating microchannel equipment and rotating microchannel equipment for demulsification.
3. The hydrogen fluoride gas treatment process according to claim 2, wherein: the modification treatment is that the wall surface in the microchannel equipment is coated with modified cross-linked polyethylene glycol, dimethyl polysilane or phenyl polysilane to form a layer of uniform protective film.
4. A hydrogen fluoride gas treatment process according to claim 1, 2 or 3, characterized in that: the molecular sieve is a 4A molecular sieve.
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Citations (6)
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| US6221132B1 (en) * | 1999-10-14 | 2001-04-24 | Air Products And Chemicals, Inc. | Vacuum preparation of hydrogen halide drier |
| EP1674425A1 (en) * | 2004-12-21 | 2006-06-28 | Davy Process Technology (Switzerland) AG | Process for the purification of gaseous hydrogen fluoride |
| DE102011111316A1 (en) * | 2011-08-26 | 2013-02-28 | Plinke Gmbh | Purifying and concentrating hydrogen fluoride containing sulfuric acid, comprises stripping hydrogen fluoride containing sulfuric acid with steam in countercurrent manner, to obtain stripped sulfuric acid, and concentrating sulfuric acid |
| CN107934915A (en) * | 2017-12-29 | 2018-04-20 | 云南瓮福云天化氟化工科技有限公司 | The purification method of impurity in-kind of anhydrous hydrogen fluoride production process |
| CN110683514A (en) * | 2019-10-29 | 2020-01-14 | 贵州新东浩化工材料科技有限公司 | Method for purifying and preparing hydrogen fluoride |
| CN111807325A (en) * | 2020-01-22 | 2020-10-23 | 浙江凯圣氟化学有限公司 | Reactive ultrasonic rectification purification method for HF electronic gas |
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2020
- 2020-12-22 CN CN202011533873.0A patent/CN112607708B/en active Active
Patent Citations (6)
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| US6221132B1 (en) * | 1999-10-14 | 2001-04-24 | Air Products And Chemicals, Inc. | Vacuum preparation of hydrogen halide drier |
| EP1674425A1 (en) * | 2004-12-21 | 2006-06-28 | Davy Process Technology (Switzerland) AG | Process for the purification of gaseous hydrogen fluoride |
| DE102011111316A1 (en) * | 2011-08-26 | 2013-02-28 | Plinke Gmbh | Purifying and concentrating hydrogen fluoride containing sulfuric acid, comprises stripping hydrogen fluoride containing sulfuric acid with steam in countercurrent manner, to obtain stripped sulfuric acid, and concentrating sulfuric acid |
| CN107934915A (en) * | 2017-12-29 | 2018-04-20 | 云南瓮福云天化氟化工科技有限公司 | The purification method of impurity in-kind of anhydrous hydrogen fluoride production process |
| CN110683514A (en) * | 2019-10-29 | 2020-01-14 | 贵州新东浩化工材料科技有限公司 | Method for purifying and preparing hydrogen fluoride |
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Non-Patent Citations (1)
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