CN114524421A - Method for recovering nitrogen trifluoride from cold trap blow-down gas and preparing hydrofluoric acid - Google Patents

Method for recovering nitrogen trifluoride from cold trap blow-down gas and preparing hydrofluoric acid Download PDF

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CN114524421A
CN114524421A CN202210219052.2A CN202210219052A CN114524421A CN 114524421 A CN114524421 A CN 114524421A CN 202210219052 A CN202210219052 A CN 202210219052A CN 114524421 A CN114524421 A CN 114524421A
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gas
cold trap
tower
temperature
hydrofluoric acid
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冀延治
宋富财
武建鹏
李海军
王永迪
邱世杰
张帅
袁瑞玲
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Peric Special Gases Co Ltd
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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
    • C01B21/00—Nitrogen; Compounds thereof
    • C01B21/082—Compounds containing nitrogen and non-metals and optionally metals
    • C01B21/083—Compounds containing nitrogen and non-metals and optionally metals containing one or more halogen atoms
    • C01B21/0832—Binary compounds of nitrogen with halogens
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J19/24—Stationary reactors without moving elements inside
    • 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
    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/00002—Chemical plants
    • B01J2219/00004—Scale aspects
    • B01J2219/00006—Large-scale industrial plants
    • 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
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02C—CAPTURE, STORAGE, SEQUESTRATION OR DISPOSAL OF GREENHOUSE GASES [GHG]
    • Y02C20/00—Capture or disposal of greenhouse gases
    • Y02C20/30—Capture or disposal of greenhouse gases of perfluorocarbons [PFC], hydrofluorocarbons [HFC] or sulfur hexafluoride [SF6]

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  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
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Abstract

The invention provides a method for recovering nitrogen trifluoride from cold trap blow-down gas and preparing hydrofluoric acid, which comprises the following steps of firstly sending blow-down tail gas into a buffer tank through a blow-down gas feeding pipe, and removing N in feed gas in a high-temperature cracking tower2F2The gas passing through the buffer tank enters a high-temperature cracking tower, and HF and F generated by the high-temperature cracking tower are absorbed in the falling film tower2The cooled gas flows into an HF storage tank, the gas flowing out of the falling film tower enters a low-temperature cooling tower through a pipeline, the gas passing through the low-temperature cooling tower enters an ultralow-temperature cold trap for liquefaction and collection, and N in the ultralow-temperature cold trap is removed by adopting a method of vacuumizing the ultralow-temperature cold trap2/O2Impurities when collecting and liquefying NF in a cold trap3、N2After the O gas reaches the preset amount, the temperature of the cold trap is raised, and the NF is pressed by using the pressure3、N2O gas is pressed into the gas storage tank. The method has low production cost and simple operation, and effectively solves the problem of discharging NF in HF removal by the traditional process3Problem of consumption of lye, N2F2The risk of (2) is high.

Description

Method for recovering nitrogen trifluoride from cold trap blow-down gas and preparing hydrofluoric acid
Technical Field
The invention belongs to the technical field of cold trap blow-off gas treatment, and particularly relates to a method for recovering nitrogen trifluoride from cold trap blow-off gas and preparing hydrofluoric acid.
Background
Nitrogen trifluoride NF3Is a synthesized colorless and tasteless gas, is mainly applied to the microelectronic industry, is an excellent plasma etching agent and cleaning agent, and is NF for silicon semiconductor materials3Has excellent etching speed and selectivity, and has high cleaning efficiency and no trace when being used as a gas cleaning agent. Furthermore, NF3The fluorine source can be used as a fluorine source in high-energy laser, an electrochemical fluorinating agent, a reagent for producing perfluorinated organic and inorganic compounds, a reagent for preparing the tetrafluorohydrazine and the fluorozirconate glass, and a special welding gas can be used for separating and purifying uranium and plutonium by utilizing the characteristic of large reaction heat of the fluorine source and the hydrogen.
Hydrofluoric acid is an aqueous solution of hydrogen fluoride gas, clear, colorless, fuming, corrosive liquid, with a severe pungent odor. Hydrofluoric acid is a weak acid and is extremely corrosive. Hydrofluoric acid can be used for etching glass, and can be used for carving patterns, marking scales and characters; it is used by the semiconductor industry to remove oxides from silicon surfaces, it can be used as a catalyst in the alkylation of isobutane with n-butenes in refineries, and hydrofluoric acid is also used in "pickling" processes to remove oxygen-containing impurities from stainless steel surfaces.
The cold trap blow-down gas usually contains NF3、N2O、N2F2HF and the like, the existing method for removing HF usually adopts a mode of lye absorption to remove, but the method has the problem of discharging NF3Problem of (2), problem of consumption of alkali solution and N2F2The risk of (2) is high.
Therefore, the effective system process and method are adopted to purify the cold trap blow-down gas and the NF3The production efficiency and the production cost are reduced, and the effect of putting a great deal of weight is achieved.
Disclosure of Invention
The technical problem to be solved by the present invention is to provide a method for recovering nitrogen trifluoride from cold trap exhaust gas and preparing hydrofluoric acid, so as to solve the problems in the background art mentioned above.
In order to solve the technical problems, the invention adopts the technical scheme that: a system for recovering nitrogen trifluoride from cold trap blow-down gas and preparing hydrofluoric acid comprises a buffer tank, a high-temperature cracking tower, a falling film tower, a low-temperature cooling tower, a cold trap and a gas storage tank;
a blowdown gas feeding pipe is arranged on the buffer tank, and the buffer tank, the high-temperature cracking tower and the falling film tower are communicated in sequence;
the side end of the falling film tower is communicated with a low-temperature cooling tower, the low-temperature cooling tower is communicated with a cold trap, and the top end of the cold trap is communicated with a gas storage tank through a vacuum pump.
Further, the bottom end of the falling film tower is communicated with an HF storage tank.
Furthermore, a first liquid nitrogen inlet is formed in the bottom side of the low-temperature cooling tower, and a second liquid nitrogen inlet is formed in the position, close to the top end, of the cold trap.
A method for recovering nitrogen trifluoride from cold trap blow-down gas and preparing hydrofluoric acid comprises the following steps:
s1, conveying the tail gas of the pollution discharge into a buffer tank through a pollution discharge gas conveying pipe, and controlling the balance pressure of the gas to be 0-0.2 MPa;
s2, removing N in raw material gas in a high-temperature cracking tower2F2The gas passing through the buffer tank enters a high-temperature cracking tower, the temperature of the high-temperature cracking tower is 150-350 ℃, and the working pressure is 0-0.2 MPa;
s3 absorption of HF in falling film column and F from pyrolysis column2Absorbed HF and F2And H2Cooling the HF generated by the O, and then flowing into an HF storage tank to prepare hydrofluoric acid, wherein the working pressure is 0-0.2 MPa;
s4, introducing gas flowing out of the falling film tower into a low-temperature cooling tower through a pipeline to remove residual HF impurities, wherein the gas outlet temperature of the low-temperature cooling tower is-125 ℃ to-40 ℃;
s5, the gas passing through the low-temperature cooling tower enters the ultra-low temperature cold trap through a pipeline for liquefaction and collection, and the N in the ultra-low temperature cold trap is removed by adopting a method of vacuumizing the ultra-low temperature cold trap2/O2Impurities, the temperature of a gas outlet of the cold trap is-185 ℃ to-135 ℃, the working pressure of the ultralow temperature cold trap is-0.05 MPa to 0MPa, and NF is collected and liquefied in the cold trap3、N2After the O gas reaches the preset amount, the cold trap is heated, and NF is pumped by a vacuum pump3、N2And O gas is pressed into the gas storage tank.
Further, the temperature of the low-temperature cooling tower and the cold trap is respectively adjusted to the flow of the liquid nitrogen at the first liquid nitrogen inlet and the second liquid nitrogen inlet.
Furthermore, the buffer tank is communicated with the high-temperature cracking tower in a sealing way through a pipeline, and the high-temperature cracking tower is communicated with the falling film tower in a sealing way through a pipeline.
Further, the pressure of the buffer tank is adjusted by adjusting the gas flow rate of a gas flow adjusting valve in front of the buffer tank.
Furthermore, the falling film tower can remove redundant HF impurities in the sewage gas and prepare hydrofluoric acid at the same time, and the prepared hydrofluoric acid is stored in an HF storage tank.
Compared with the prior art, the invention has the following advantages:
the method has low production cost and simple operation, and effectively solves the problem of discharging NF in HF removal by the traditional process3Problem of consumption of lye, N2F2The risk of (2) is high.
Drawings
FIG. 1 is a schematic diagram of the system of the present invention;
description of reference numerals:
1-a buffer tank; 2-a pyrolysis tower; 3-a falling film column; 4-HF storage tank; 5-a cryogenic cooling tower; 6-a first liquid nitrogen inlet; 7-cold trap; 8-a second liquid nitrogen inlet; 9-a vacuum pump; 10-gas storage tank.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Embodiment 1, as shown in fig. 1, the present invention provides a technical solution: a system for recovering nitrogen trifluoride from cold trap blow-down gas and preparing hydrofluoric acid comprises a buffer tank 1, a high-temperature cracking tower 2, a falling film tower 3, a low-temperature cooling tower 5, a cold trap 7 and a gas storage tank 10;
the buffer tank 1 is provided with a blow-down gas feeding pipe, NF in the blow-down gas3：40％～80％、N2O：1％～2％、N2F2：5％～20％、HF：20％～40％。
The buffer tank 1, the high-temperature cracking tower 2 and the falling film tower 3 are communicated in sequence; the bottom end of the falling film tower 3 is communicated with an HF storage tank 4.
The side end of the falling film tower 3 is communicated with a low-temperature cooling tower 5, the low-temperature cooling tower 5 is communicated with a cold trap 7, a first liquid nitrogen inlet 6 is formed in the bottom side of the low-temperature cooling tower 5, and a second liquid nitrogen inlet 8 is formed in the position, close to the top end, of the cold trap 7.
The roof of the cold trap 7The end is communicated with a vacuum pump 9 and a gas storage tank 10 through a pipeline, and NF is collected in a cold trap3When gas is in use, the negative pressure of the vacuum pump is used for pumping N2、O2Pumping away; after the collection is finished, the temperature and the pressure are raised, and NF is pressed by the pressure3And N2O is pressed into the gas tank 10.
Embodiment 2, the present invention provides a technical solution: a method for recovering nitrogen trifluoride from cold trap blow-down gas and preparing hydrofluoric acid comprises the following steps:
s1, conveying the tail gas of the pollution discharge into a buffer tank 1 through a pollution discharge gas conveying pipe, and controlling the balance pressure of the gas to be 0-0.2 MPa, wherein the pressure of the buffer tank 1 is adjusted by adjusting the gas flow rate of a gas flow adjusting valve in front of the buffer tank 1;
s2, removing N in the raw material gas in the high-temperature cracking tower 22F2The gas passing through the buffer tank 1 enters a high-temperature cracking tower 2, the buffer tank 1 is hermetically communicated with the high-temperature cracking tower 2 through a pipeline, the high-temperature cracking tower 2 is hermetically communicated with a falling film tower 3 through a pipeline, the temperature of the high-temperature cracking tower is 150-350 ℃, and the working pressure of the high-temperature cracking tower is 0-0.2 MPa;
s3 absorption of HF in falling film column 3 and F produced in pyrolysis column 22Absorbed HF and F2And H2Cooling the HF generated by the O, and then flowing into an HF storage tank 4 to prepare hydrofluoric acid, wherein the working pressure is 0-0.2 MPa; the falling film tower 3 can remove redundant HF impurities in the sewage gas and simultaneously prepare hydrofluoric acid, and the prepared hydrofluoric acid is stored through an HF storage tank 4.
S4, introducing the gas flowing out of the falling film tower 3 into a low-temperature cooling tower 5 through a pipeline to remove residual HF impurities, wherein the gas outlet temperature of the low-temperature cooling tower 5 is-125 ℃ to-40 ℃;
s5, the gas passing through the low-temperature cooling tower 5 enters the ultra-low-temperature cold trap 7 through a pipeline for liquefaction and collection, and the N in the ultra-low-temperature cold trap 7 is removed by adopting a method of vacuumizing the ultra-low-temperature cold trap 72/O2Impurities, wherein the temperatures of the low-temperature cooling tower 5 and the cold trap 7 are respectively adjusted by the flow of liquid nitrogen at a first liquid nitrogen inlet 6 and a second liquid nitrogen inlet 8;
cold trap 7The temperature of the gas outlet is-185 ℃ to-135 ℃, the working pressure of the ultralow temperature cold trap is-0.05 MPa to 0MPa, and NF is collected and liquefied in the cold trap 73、N2After the O gas reaches the preset amount, the temperature of the cold trap 7 is raised, and the pressure formed after the materials in the cold trap are gasified is utilized to lead the NF to3、N2O gas is forced into the gas storage tank 10.
Example 3 containing NF3、N2O、N2F2HF cold trap blow-down gas in proportions of 40%, 2%, 20%, 38% was removed by the method of example 2 to remove N2F2And preparing HF, the process steps are as follows: 1-a buffer tank; 2-a pyrolysis tower; 3-a falling film column; 4-HF storage tank; 5-a cryogenic cooling tower; 6-a first liquid nitrogen inlet; 7-cold trap; 8-a second liquid nitrogen inlet; 9-a vacuum pump; 10-gas storage tank
Firstly, the blow-off gas enters a buffer tank 1, the pressure is controlled to be about 0.15MPa, and then the blow-off gas enters a high-temperature cracking tower 2 through a pipeline, the working pressure is controlled to be 0.15MPa, and the temperature is controlled to be 200 +/-10 ℃.
Removal of N2F2The gas flows into the falling film tower 3 through a pipeline to absorb HF and N in the gas2F2F produced by decomposition2And H2And collecting HF generated by O at the bottom of the tower to prepare hydrofluoric acid, storing the hydrofluoric acid in an HF storage tank 4, controlling the temperature of an air outlet to be 10 +/-2 ℃, and enabling the gas to enter a low-temperature cooling tower 5 through a pipeline.
Then opening the regulating valve to make the liquid nitrogen enter the low-temperature cooling tower 5 and the cold trap 7, controlling the temperature of the discharge port of the low-temperature cooling tower 5 at minus 90 +/-2 ℃, the temperature of the vacuum port of the cold trap 7 at minus 170 +/-2 ℃, and the pressure of the cold trap at minus 0.02 MPa.
Removing residual high boiling point impurities such as HF via low temperature cooling tower 5, introducing the residual gas into cold trap by pressure difference, wherein NF is obtained3And N2O high boiling point gas is condensed into liquid in the cold trap and flows into the bottom of the cold trap 7, and low boiling point impurity nitrogen and oxygen are pumped out of the cold trap 7 by a vacuum pumping system through a vacuum port.
After low boiling point impurities are pumped out of the cold trap 7, the inlet regulating valve of the vacuum pump 9 is closed, the temperature of the air outlet of the cold trap is controlled to be minus 100 +/-2 ℃ by the liquid nitrogen regulating valve, and NF3And N2The O liquid is vaporized into gas and enters the gas storage tank 10 through the gas outlet.
NF obtained by the present embodiment3The gas purity reaches 94%, wherein the N2O gas accounts for 5%.
Example 4 volume fraction of NF3 using the method of example 2 was 60%, N2O、N2F2And HF respectively accounting for 2%, 15% and 23%, and treating the cold trap blow-down gas to finally obtain NF3The gas purity reaches 96 percent, wherein N is2The O gas accounts for 3%.
Example 5 NF Synthesis Using the procedure of example 23Is 70% by volume, N2O、N2F2And HF respectively accounting for 1%, 9% and 20%, and treating the cold trap blow-down gas to obtain the final NF3The gas purity reaches 98 percent, wherein N2The O gas accounts for 1%.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims (8)

1. A system for recovering nitrogen trifluoride from cold trap blow-down gas and preparing hydrofluoric acid is characterized by comprising a buffer tank (1), a high-temperature cracking tower (2), a falling film tower (3), a low-temperature cooling tower (5), a cold trap (7) and a gas storage tank (10);
a blowdown gas feeding pipe is arranged on the buffer tank (1), and the buffer tank (1), the high-temperature cracking tower (2) and the falling film tower (3) are communicated in sequence;
the side end of the falling film tower (3) is communicated with a low-temperature cooling tower (5), the low-temperature cooling tower (5) is communicated with a cold trap (7), and the top end of the cold trap (7) is communicated with a vacuum pump (9) and a gas storage tank (10) through a pipeline.
2. The system for recovering nitrogen trifluoride and preparing hydrofluoric acid from cold trap blow-down gas according to claim 1, wherein the bottom end of the falling film tower (3) is connected with an HF storage tank (4).
3. The system for recovering nitrogen trifluoride and preparing hydrofluoric acid from cold trap blow-down gas according to claim 1, wherein the first liquid nitrogen inlet (6) is opened at the bottom side of the low-temperature cooling tower (5), and the second liquid nitrogen inlet (8) is opened at the top end of the cold trap (7).
4. A method for recovering nitrogen trifluoride from cold trap blow-down gas and preparing hydrofluoric acid is characterized by comprising the following steps:
s1, conveying the tail gas of the pollution discharge into a buffer tank (1) through a pollution discharge gas conveying pipe, and controlling the balance pressure of the gas to be 0-0.2 MPa;
s2, removing N in the raw material gas in the high-temperature cracking tower (2)2F2The gas passing through the buffer tank (1) enters a high-temperature cracking tower (2), the temperature of the high-temperature cracking tower is 150-350 ℃, and the working pressure is 0-0.2 MPa;
s3, absorbing HF in the falling film tower (3) and F generated in the pyrolysis tower (2)2Absorbed HF and F2And H2Cooling the HF generated by the O, and then flowing into an HF storage tank (4) to prepare hydrofluoric acid, wherein the working pressure is 0-0.2 MPa;
s4, introducing gas flowing out of the falling film tower (3) into a low-temperature cooling tower (5) through a pipeline to remove residual HF impurities, wherein the gas outlet temperature of the low-temperature cooling tower (5) is-125 ℃ to-40 ℃;
s5, the gas passing through the low-temperature cooling tower (5) enters the ultra-low-temperature cold trap (7) through a pipeline for liquefaction and collection, and N in the gas is removed by adopting a method of vacuumizing the ultra-low-temperature cold trap (7)2/O2Impurities are collected and liquefied in the cold trap (7), the temperature of a gas outlet of the cold trap (7) is-185 ℃ to-135 ℃, the working pressure of the ultralow temperature cold trap is-0.05 MPa to 0MPa, and the impurities are provided by a vacuum pump (9)3、N2After the predetermined amount of O gas is reached, the temperature of the cold trap (7) is raised, and NF is pressurized by using the pressure3、N2O gas is pressed into the gas storage tank (10).
5. The method for recovering nitrogen trifluoride and preparing hydrofluoric acid from cold trap blow-down gas according to claim 4, wherein the temperatures of the cryogenic cooling tower (5) and the cold trap (7) are adjusted by the flow rates of the liquid nitrogen of the first liquid nitrogen inlet (6) and the second liquid nitrogen inlet (8), respectively.
6. The method for recovering nitrogen trifluoride and preparing hydrofluoric acid from cold trap blow-down gas according to claim 4, wherein the buffer tank (1) is in sealed communication with the pyrolysis tower (2) through a pipeline, and the pyrolysis tower (2) is in sealed communication with the falling film tower (3) through a pipeline.
7. The method for recovering nitrogen trifluoride and preparing hydrofluoric acid from cold trap blow-down gas according to claim 4, wherein the pressure of the buffer tank (1) is adjusted by adjusting the gas flow rate of a gas flow regulating valve in front of the buffer tank (1).
8. The method for recovering nitrogen trifluoride and preparing hydrofluoric acid from cold trap exhaust gas according to claim 4, wherein hydrofluoric acid can be prepared while removing excessive HF impurities in the exhaust gas by the falling film tower (3), and the prepared hydrofluoric acid is stored by an HF storage tank (4).
CN202210219052.2A 2022-03-08 2022-03-08 Method for recovering nitrogen trifluoride from cold trap blow-down gas and preparing hydrofluoric acid Pending CN114524421A (en)

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Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4980144A (en) * 1988-06-01 1990-12-25 Mitsui Toatsu Chemicals, Inc. Process for purifying nitrogen trifluoride gas
JPH07330317A (en) * 1994-06-02 1995-12-19 Nissan Chem Ind Ltd Low-temperature distillation apparatus for nitrogen trifluoride gas
CN1450202A (en) * 2003-04-30 2003-10-22 中国船舶重工集团公司第七一八研究所 Technological method and equipment for preparing nitrogen trifluoride gas
CN1450203A (en) * 2003-04-30 2003-10-22 中国船舶重工集团公司第七一八研究所 Fine preparation process for high-purity nitrogen trifluoride gas
CN1727279A (en) * 2005-07-27 2006-02-01 中国船舶重工集团公司第七一八研究所 Method for purifying gas of nitrogen trifluoride
CN111085086A (en) * 2019-12-31 2020-05-01 中船重工（邯郸）派瑞特种气体有限公司 NF prepared by electrolysis3System and method for recovering HF in tail gas of electrolysis system
CN112191081A (en) * 2020-09-01 2021-01-08 中船重工（邯郸）派瑞特种气体有限公司 Method and system for treating hydrogen fluoride tail gas generated in nitrogen trifluoride preparation process
CN112742158A (en) * 2020-12-30 2021-05-04 中船重工（邯郸）派瑞特种气体有限公司 Hydrogen fluoride waste gas treatment system and method in nitrogen trifluoride electrolysis preparation process

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4980144A (en) * 1988-06-01 1990-12-25 Mitsui Toatsu Chemicals, Inc. Process for purifying nitrogen trifluoride gas
JPH07330317A (en) * 1994-06-02 1995-12-19 Nissan Chem Ind Ltd Low-temperature distillation apparatus for nitrogen trifluoride gas
CN1450202A (en) * 2003-04-30 2003-10-22 中国船舶重工集团公司第七一八研究所 Technological method and equipment for preparing nitrogen trifluoride gas
CN1450203A (en) * 2003-04-30 2003-10-22 中国船舶重工集团公司第七一八研究所 Fine preparation process for high-purity nitrogen trifluoride gas
CN1727279A (en) * 2005-07-27 2006-02-01 中国船舶重工集团公司第七一八研究所 Method for purifying gas of nitrogen trifluoride
CN111085086A (en) * 2019-12-31 2020-05-01 中船重工（邯郸）派瑞特种气体有限公司 NF prepared by electrolysis3System and method for recovering HF in tail gas of electrolysis system
CN112191081A (en) * 2020-09-01 2021-01-08 中船重工（邯郸）派瑞特种气体有限公司 Method and system for treating hydrogen fluoride tail gas generated in nitrogen trifluoride preparation process
CN112742158A (en) * 2020-12-30 2021-05-04 中船重工（邯郸）派瑞特种气体有限公司 Hydrogen fluoride waste gas treatment system and method in nitrogen trifluoride electrolysis preparation process

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
宋海华,付曼,高世选: "三氟化氮纯化的新工艺" *
杜伟华: "三氟化氮萃取精馏工艺研究" *

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