CN101570319B - Method for producing ultra-clean high-pure hydrofluoric acid - Google Patents
Method for producing ultra-clean high-pure hydrofluoric acid Download PDFInfo
- Publication number
- CN101570319B CN101570319B CN2008100496637A CN200810049663A CN101570319B CN 101570319 B CN101570319 B CN 101570319B CN 2008100496637 A CN2008100496637 A CN 2008100496637A CN 200810049663 A CN200810049663 A CN 200810049663A CN 101570319 B CN101570319 B CN 101570319B
- Authority
- CN
- China
- Prior art keywords
- hydrofluoric acid
- temperature
- gas
- percent
- still
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Landscapes
- Treating Waste Gases (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention relates to a method for producing ultra-clean high-pure hydrofluoric acid. The method comprises the following steps: (1), emptying air in a system; (2), adding a measured liquid hydrogenfluoride raw material to a rough distillation kettle with a heat exchanger for rough distillation; (3), controlling the inside pressure of the rough distillation kettle to be lower than 0.2MPa and ad ding an oxidant; (4), repeatedly condensing, refluxing and vaporizing in the rough distillation kettle; (5), pumping gas guided from a top outlet of a water condenser into the bottom of a spraying absorption tower so as to be absorbed by spraying absorption liquid which is sprayed in from the top of the absorption tower; (6), gasifying and pumping hydrofluoric acid into the absorption tower to be absorbed; (7), pumping the hydrofluoric acid at the outlet of the condenser into the absorption tower and using ultra-pure water to absorb into 48 percent to 49 percent of hydrous hydrofluoric acid solution; (8), secondarily rectifying the 48 percent to 49 percent of hydrous hydrofluoric acid solution; and (9), filtering the 48 percent to 49 percent of hydrous hydrofluoric acid solution after secondary rectification at two stages to prepare 48 percent of ultra-clean high-pure hydrofluoric acid finished product. The invention not only improves the purity of the ultra-clean high-pure hydrofluoric acid, but also increases the economic benefits and the environmental-protection benefits.
Description
Technical field
The present invention relates to a kind of method of producing super clean, high purified hydrofluoric acid, relating in particular to a kind of is the method for main material production super clean, high purified hydrofluoric acid with the liquid hydrogen fluoride.
Background technology
Hydrofluoric acid (hydrofluoric, HF), relative molecular weight 20.1, colourless liquid or gas; Has the intense stimulus smell, below 20 ℃, it is water white fuming liquid, generate the metal villiaumite with metal oxide, sodium hydroxide and carbonate reaction, character with dissolves silicon and silicate, generate fluosulfonic acid with sulphur trioxide or chlorsulfonic acid, generate organic fluorocompound, the very strong acid of water-soluble generation corrodibility with halogenated aryl hydrocarbon, alcohol, alkene, hydrocarbon reaction.Fusing point-83.7 ℃, 19.5 ℃ of boiling points, soluble in water, relative density (25 ℃) (water=1) 1.15g/cm (40% weight).That super clean, high purified hydrofluoric acid has is wide in variety, consumption is big, technical requirements is high, storage life is short and characteristics such as severe corrosive.Super clean, high purified hydrofluoric acid mainly can use with preparations such as nitric acid, Glacial acetic acid, hydrogen peroxide and ammonium hydroxide, is mainly used in the production of super large-scale integration Technology.Fast development along with electronics, information, communications industry, requirement to the purity of reagent hydrofluoric acid, impurity etc. is more and more higher, demand is also corresponding to be increased suddenly, general high-pure hydrofluoric acid far can not satisfy the harsh requirement in market, and the preparation super clean, high purified hydrofluoric acid has just become the deep processing of hydrogen fluoride production enterprise and improved one of direction of added value of product.One of key basic chemical industry material that super clean, high purified hydrofluoric acid is made as unicircuit (IC) is mainly used in the cleaning and the corrosion of chip, and its purity and cleanliness factor all have crucial influence to yield rate, electrical property and the reliability of unicircuit.
After generally adopting industrial anhydrous hydrofluoric acid to add the potassium permanganate reaction at present, directly the rectifying purifying is produced the high-purity hydrogen fluoride of ultra-clean, it is lower that this kind method makes hydrofluoric acid purity, particularly arsenous fluoride separates not exclusively in the hydrofluoric acid, so the super clean, high purified hydrofluoric acid that this method is produced is difficult to be suitable in super large-scale integration (microelectronics industry), simultaneously, processing parameter is wayward in the production process.
Summary of the invention
The object of the present invention is to provide a kind of method of producing super clean, high purified hydrofluoric acid, the impurity with in effective elimination hydrofluoric acid improves product purity greatly, to be applicable to microelectronics industry technology, especially super large-scale integration.
To achieve these goals, technical scheme of the present invention has adopted a kind of method of producing super clean, high purified hydrofluoric acid, may further comprise the steps:
(1) air in the emptying system;
(2) still that slightly heats up in a steamer that enters the band interchanger of the liquid hydrogen fluoride raw materials after will measuring slightly heats up in a steamer;
(3) slightly heating up in a steamer in the still, control is slightly heated up in a steamer the still internal pressure less than 0.2Mpa, adds oxygenant, makes a large amount of sulfurous gas and the arsenous fluoride generation that contain in the liquid hydrogen fluoride be difficult to the evaporable compound; Add weight concentration then and be 30% hydrogen peroxide;
(4) gas that steams under slightly heating up in a steamer in the still 30～50 ℃ temperature rises continuously, through topping still, then enter the water condenser that directly is contained in this top of tower, and carry out condensing reflux, vaporization repeatedly, gas, liquid two-phase reach the top contact closely repeatedly of topping still, 10～20 ℃ of the gas temperatures that the top exit of control water condenser is derived in water condenser;
(5) gas of deriving from the water condenser top exit enters from the bottom of spray absorber, and is absorbed by the spray absorption liquid that is sprayed into from this column overhead;
(6) treat that gas that the water condenser top exit is derived reaches weight 1～2% o'clock of liquid hydrogen fluoride, adjusting the condensator outlet temperature is 20～35 ℃, carries out the hydrofluoric acid gasification, and the hydrofluoric acid after the gasification feeds in the absorption tower and absorbs;
(7) absorb with ultrapure water in the hydrofluoric acid feeding absorption tower with condensator outlet, tower still temperature is 40～60 ℃, the body of the tower temperature is 40～50 ℃, and the condensator outlet temperature is 20～40 ℃, condensed liquid-absorbent be 48%～49% the water hydrofluoric acid solution arranged;
(8) 48%～49% hydrofluoric acid solution is carried out secondary rectifying, column bottom temperature is between 110～130 ℃, and the tower top outlet temperature is 105～110 ℃;
(9) from secondary rectifying come out purified after hydrogen fluoride gas after condenser cooling, through two-stage filtration, filter after auto-filling is made 48% super clean, high purified hydrofluoric acid finished product.
The concrete steps of step (1) are: use the nitrogen purge system, and air in the emptying system, keeping room temperature is 19.7-24.7 ℃, and the operating station temperature is 22.09-22.31 ℃, and humidity remains on 40%.
The oxygenant that step (3) adds is preferably potassium permanganate solution, (NH
4)
2S
2O
8Or KHF
2In any or its combination, the add-on of oxygenant is 0.5～2.5% of a raw material gross weight.
The add-on of hydrogen peroxide is 1～3% of a raw material gross weight in the step (3).
The concentration that step (5) forms after absorbing is 50～60% acid solution, is used for other technology or takes out as commodity.
Being filtered into of step (9): between hundred-grade super-clean behind one-level 0.2 μ m filtering with microporous membrane, enter secondary 0.05 μ m filtering with microporous membrane again.
It is different with the boiling point of each impurity in the liquid hydrogen fluoride that method of the present invention has made full use of liquid hydrogen fluoride, under differing temps, removes different impurity, and especially silicon makes the super clean, high purified hydrofluoric acid foreign matter content that obtains drop to minimum.The present invention has utilized oxidant potassium permanganate or (NH
4)
2S
2O
8And KHF
2, utilized the strong oxidizing property of hydrogen peroxide simultaneously, a large amount of sulfurous gas that contain in the liquid hydrogen fluoride and arsenous fluoride oxidation are generated be difficult to evaporable sulphur trioxide and K
2AsF
7The boiling point of these compounds is higher, is difficult for being taken out of in the process of slightly heating up in a steamer and is present in and slightly heats up in a steamer still bottom discharge system and take out.The present invention has promptly improved the purity of super clean, high purified hydrofluoric acid, has increased economic benefit and environmental benefit again.
The inventive method following advantage of having compared with present production technique:
(1) by the boiling point difference of each material, utilizes potassium permanganate or (NH
4)
2S
2O
8And KHF
2And the strong oxidizing property of hydrogen peroxide, thoroughly solved the difficult problem that silicon and trivalent arsenic etc. are difficult for removing, carry out secondary rectifying simultaneously, make the purity of product further improve, the super clean, high purified hydrofluoric acid that makes reaches semi-conductor SEMI-C12 standard, be satisfied with the microelectronics industry technology, especially the needs of super large-scale integration.The finished product index is: purity: negatively charged ion≤25ppb, positively charged ion≤0.03ppb.
(2) waste acid liquor that is produced in the production process of the present invention, content is generally hydrofluoric acid, silicofluoric acid etc., and concentration is about 50～60%, can be used for the sodium aluminum fluoride production line, has alleviated environmental protection pressure greatly, has reduced consumption, has saved cost.
(3) the present invention carries out membrane filtration twice to the hydrofluoric acid work in-process, and it is minimum to make in the super clean, high purified hydrofluoric acid that granule foreign content drops to, and reaches semi-conductor SEMI-C12 standard.Granule number is 0.2 μ m≤50.Method of the present invention has solved the problem that can not or be difficult to prepare super clean, high purified hydrofluoric acid at present; utilize method of the present invention can carry out large-scale production; the control easily of efficient height, technological process, safety and environmental protection, exploitativeness are strong; have good social benefit and economic benefit, be easy to apply.
Embodiment
Embodiment 1
The method of present embodiment is specially: use the nitrogen purge system, air in the emptying system is kept 22.2 ℃ of room temperatures, and the operating station temperature is 22.2 ℃, and humidity remains on 40%.The liquid hydrogen fluoride raw material of 350kg is flowed out in the storage bottle, and what add the band interchanger slightly heats up in a steamer still.Slightly heating up in a steamer in the still, control is slightly heated up in a steamer the still internal pressure less than 0.2Mpa, adds (NH
4)
2S
2O
8, its add-on is 5.25kg, makes a large amount of sulfurous gas and the arsenous fluoride generation that contain in the liquid hydrogen fluoride be difficult to the evaporable compound; The hydrogen peroxide that adds 30% (weight ratio) then, the add-on of hydrogen peroxide are 7kg.Slightly heating up in a steamer temperature in the kettle is that the gas that steams under 30～50 ℃ rises continuously, through topping still, then enter the water condenser that directly is contained in this top of tower, and carry out condensing reflux, vaporization repeatedly, gas, liquid two-phase reach the top contact closely repeatedly of topping still, 15 ℃ of the gas temperatures that the top exit of control water condenser is derived in water condenser.The gas of deriving from the water condenser top exit enters this tower from the bottom of spray absorber, and is absorbed by the spray absorption liquid that is sprayed into from this column overhead, absorbs into 50～60% acid solution, is used for other technology of our company and uses or take out as commodity.When treating that gas that the water condenser top exit is derived reaches the weight 1.5% of anhydrous hydrofluoric acid, adjusting the condensator outlet temperature is 35 ℃, carries out the hydrofluoric acid gasification, and the hydrofluoric acid after the gasification feeds in the absorption tower and absorbs.The hydrofluoric acid of condensator outlet fed in the absorption tower absorb with ultrapure water, tower still temperature is 50 ℃, and the body of the tower temperature is 45 ℃, 30 ℃ of condensator outlet temperature, condensed liquid-absorbent be 48%～49% the water hydrofluoric acid solution arranged.Hydrofluoric acid solution with 48%～49% carries out secondary rectifying, and column bottom temperature is between 120 ℃, and the tower top outlet temperature is 105 ℃; Come out from secondary rectifying, the hydrogen fluoride gas that purifying is crossed is after the condenser cooling, between hundred-grade super-clean behind one-level 0.2 μ m filtering with microporous membrane, enter secondary 0.05 μ m filtering with microporous membrane (granule number be 0.3 μ m≤100) again, after the filtration the super clean, high purified hydrofluoric acid finished product of 630kg 48% (wt).Analytical results: granule number is 0.2 μ m≤50, purity: negatively charged ion≤25ppb, positively charged ion≤0.03ppb.
Embodiment 2
The method of present embodiment is specially: use the nitrogen purge system, air in the emptying system.Keep 23.5 ℃ of room temperatures, the operating station is at 22.3 ℃, and humidity remains on 40%, and the liquid hydrogen fluoride raw material of 250kg is flowed out in the storage bottle, and what add the band interchanger slightly heats up in a steamer still.Slightly heating up in a steamer in the still, control is slightly heated up in a steamer the still internal pressure less than 0.2Mpa, adds 2.5kg KHF
2, make a large amount of sulfurous gas and the arsenous fluoride generation that contain in the anhydrous hydrogen fluoride for industrial use be difficult to the evaporable compound; The hydrogen peroxide that adds 30% (weight ratio) then, hydrogen peroxide account for the 5kg of anhydrous hydrogen fluoride for industrial use dosage.Slightly heating up in a steamer temperature in the kettle is that the gas that steams under 30～50 ℃ rises continuously, through topping still, then enter the water condenser that directly is contained in this top of tower, and carry out condensing reflux, vaporization repeatedly, gas, liquid two-phase reach the top contact closely repeatedly of topping still, 20 ℃ of the gas temperatures that the top exit of control water condenser is derived in water condenser.The gas of deriving from the water condenser top exit enters this tower from the bottom of spray absorber, and is absorbed by the spray absorption liquid that is sprayed into from this column overhead, absorbs into 50～60% acid solutions, is used for other technology of our company or take-away.When treating that gas that the water condenser top exit is derived reaches the weight 2% of anhydrous hydrofluoric acid, adjusting the condensator outlet temperature is 35 ℃, carries out the hydrofluoric acid gasification, and the hydrofluoric acid after the gasification feeds in the absorption tower and absorbs.The hydrofluoric acid of condensator outlet fed in the absorption tower absorb with ultrapure water, tower still temperature is 60 ℃, and the body of the tower temperature is 50 ℃, 40 ℃ of condensator outlet temperature, condensed liquid-absorbent be 48%～49% the water hydrofluoric acid solution arranged.Hydrofluoric acid solution with 48%～49% carries out secondary rectifying, and column bottom temperature is between 130 ℃, and the tower top outlet temperature is controlled at 110 ℃; Come out from secondary rectifying, the hydrogen fluoride gas that purifying is crossed is after the condenser cooling, between hundred-grade super-clean behind one-level 0.2 μ m filtering with microporous membrane, enter secondary 0.05 μ m filtering with microporous membrane (granule number be 0.3 μ m≤100) again, after the filtration the super clean, high purified hydrofluoric acid finished product of 390kg 49% (wt).Analytical results: granule number is 0.2 μ m≤50, purity: negatively charged ion≤25ppb, positively charged ion≤0.03ppb.
It should be noted last that: above embodiment is only in order to explanation, and unrestricted technical scheme of the present invention, although the present invention is had been described in detail with reference to the foregoing description, those of ordinary skill in the art is to be understood that: still can make amendment or be equal to replacement the present invention, and not breaking away from any modification or partial replacement of the spirit and scope of the present invention, it all should be encompassed in the middle of the claim scope of the present invention.
Claims (3)
1. method of producing super clean, high purified hydrofluoric acid is characterized in that: may further comprise the steps:
(1) air in the emptying system;
(2) still that slightly heats up in a steamer that enters the band interchanger of the liquid hydrogen fluoride raw materials after will measuring slightly heats up in a steamer;
(3) slightly heating up in a steamer in the still, control is slightly heated up in a steamer the still internal pressure less than 0.2MPa, adds oxygenant, makes a large amount of sulfurous gas and the arsenous fluoride generation that contain in the liquid hydrogen fluoride be difficult to the evaporable compound; Add weight concentration then and be 30% hydrogen peroxide; The add-on of hydrogen peroxide is 1～3% of a raw material gross weight; Wherein, oxygenant is potassium permanganate solution, (NH
4)
2S
2O
8Or KHF
2In any or its combination, the add-on of oxygenant is 0.5～2.5% of a raw material gross weight;
(4) gas that steams under slightly heating up in a steamer in the still 30～50 ℃ temperature rises continuously, through topping still, then enter the water condenser that directly is contained in this top of tower, and carry out condensing reflux, vaporization repeatedly, gas, liquid two-phase reach the top contact closely repeatedly of topping still in water condenser, the gas temperature that the top exit of control water condenser is derived is 10～20 ℃;
(5) gas of deriving from the water condenser top exit enters from the bottom of spray absorber, and is absorbed by the spray absorption liquid that is sprayed into from this column overhead;
(6) treat that gas that the water condenser top exit is derived reaches 1 of liquid hydrogen fluoride weight～2% o'clock, adjusting the condensator outlet temperature is 20～35 ℃, carries out the hydrofluoric acid gasification, and the hydrofluoric acid after the gasification feeds in the absorption tower and absorbs;
(7) absorb with ultrapure water in the hydrofluoric acid feeding absorption tower with condensator outlet, tower still temperature is 40～60 ℃, the body of the tower temperature is 40～50 ℃, and the condensator outlet temperature is 20～40 ℃, condensed liquid-absorbent be 48%～49% the water hydrofluoric acid solution arranged;
(8) 48%～49% hydrofluoric acid solution is carried out secondary rectifying, column bottom temperature is between 110～130 ℃, and the tower top outlet temperature is 105～110 ℃;
(9) from secondary rectifying come out purified after hydrogen fluoride gas after condenser cooling, through two-stage filtration, promptly earlier between hundred-grade super-clean behind one-level 0.2 μ m filtering with microporous membrane, enter secondary 0.05 μ m filtering with microporous membrane again; Filter after auto-filling is made 48% super clean, high purified hydrofluoric acid finished product; The granule number that wherein obtains the hydrofluoric acid finished product is 0.2 μ m≤50, purity: negatively charged ion≤25ppb, positively charged ion≤0.03ppb.
2. the method for production super clean, high purified hydrofluoric acid according to claim 1, it is characterized in that: the concrete steps of step (1) are: use the nitrogen purge system, and air in the emptying system, keeping room temperature is 19.7～24.7 ℃, the operating station temperature is 22.09～22.31 ℃, and humidity remains on 40%.
3. the method for production super clean, high purified hydrofluoric acid according to claim 1 is characterized in that: the concentration that step (5) forms after absorbing is 50～60% acid solution, is used for other technology or takes out as commodity.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2008100496637A CN101570319B (en) | 2008-04-28 | 2008-04-28 | Method for producing ultra-clean high-pure hydrofluoric acid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2008100496637A CN101570319B (en) | 2008-04-28 | 2008-04-28 | Method for producing ultra-clean high-pure hydrofluoric acid |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101570319A CN101570319A (en) | 2009-11-04 |
| CN101570319B true CN101570319B (en) | 2011-04-06 |
Family
ID=41229823
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2008100496637A Active CN101570319B (en) | 2008-04-28 | 2008-04-28 | Method for producing ultra-clean high-pure hydrofluoric acid |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101570319B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104973573B (en) * | 2015-06-18 | 2017-03-29 | 多氟多化工股份有限公司 | A kind of preparation method of the preparation method and high-pure hydrofluoric acid of high-purity hydrogen fluoride |
| CN110127616B (en) * | 2019-04-17 | 2021-05-04 | 苏州汉谱埃文材料科技有限公司 | Purification process of ultrapure acid liquid |
| CN111704109A (en) * | 2020-07-13 | 2020-09-25 | 南京德源环保科技发展有限公司 | Method and system for preparing electronic-grade hydrofluoric acid by continuous method |
| CN112010263B (en) * | 2020-08-31 | 2022-08-02 | 北京化工大学 | Production device and production method of electronic-grade hydrofluoric acid |
| CN112897467B (en) * | 2021-03-18 | 2022-09-30 | 福建省建阳金石氟业有限公司 | Production method of electronic-grade hydrofluoric acid |
| CN114146586B (en) * | 2021-12-30 | 2023-11-21 | 金宏气体股份有限公司 | Device and method for preparing hydrofluoric acid solution |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3166379A (en) * | 1962-06-04 | 1965-01-19 | Union Carbide Corp | Purification of hydrofluoric acid |
| CN1054574A (en) * | 1990-03-02 | 1991-09-18 | 纳幕尔杜邦公司 | Hydrofluoric method of purification |
| CN101125639A (en) * | 2007-08-06 | 2008-02-20 | 江阴市润玛电子材料有限公司 | Method for purifying ultra-pure hydrofluoric acid |
-
2008
- 2008-04-28 CN CN2008100496637A patent/CN101570319B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3166379A (en) * | 1962-06-04 | 1965-01-19 | Union Carbide Corp | Purification of hydrofluoric acid |
| CN1054574A (en) * | 1990-03-02 | 1991-09-18 | 纳幕尔杜邦公司 | Hydrofluoric method of purification |
| CN101125639A (en) * | 2007-08-06 | 2008-02-20 | 江阴市润玛电子材料有限公司 | Method for purifying ultra-pure hydrofluoric acid |
Non-Patent Citations (2)
| Title |
|---|
| JP特表平11-507001A 1999.06.22 |
| 陈鸿昌.高纯氢氟酸制备的概况.《有机氟工业》.2000,(第3期),25-30. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101570319A (en) | 2009-11-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101570318B (en) | Method for producing electronic-stage hydrofluoric acid | |
| CN101570319B (en) | Method for producing ultra-clean high-pure hydrofluoric acid | |
| CN104973573B (en) | A kind of preparation method of the preparation method and high-pure hydrofluoric acid of high-purity hydrogen fluoride | |
| EP1425273B1 (en) | Heat recovery procedure | |
| KR101598401B1 (en) | Method for manufacturing high purity sulfuric acid and system thereof | |
| JP7523820B2 (en) | Separation and purification method for purifying industrial-grade high-concentration HF to electronic-grade FTrPSA | |
| CN111170320B (en) | Device and method for recycling waste acid solution for polycrystalline silicon texturing | |
| CN105565281A (en) | Preparation method for hyperpure sulphuric acid | |
| CN107055477A (en) | The method and its device of hydrogen fluoride are prepared by fluosilicic acid | |
| CN105645358A (en) | Method for preparing hydrogen fluoride from fluosilicic acid | |
| CN112742158A (en) | Hydrogen fluoride waste gas treatment system and method in nitrogen trifluoride electrolysis preparation process | |
| CN111186820A (en) | Production process and production system of high-purity sulfuric acid | |
| CN212050528U (en) | High-efficient purification system of hydrogen fluoride | |
| CN110589770A (en) | Preparation method of electronic-grade hydrofluoric acid | |
| JP5511473B2 (en) | Purification method of ethylene glycol | |
| CN101100291A (en) | Process for the recovery of sulfuric acid | |
| CN112661115B (en) | Separation and purification method for deep dehydration and impurity removal of FTrPSA refined by anhydrous HF produced by fluorite method | |
| US9896334B2 (en) | Process for purification of hydrofluoric acid including obtaining arsenious acid by-product | |
| CN112591722A (en) | Method for co-producing industrial-grade nitric acid and electronic-grade nitric acid | |
| CN211871381U (en) | High-purity sulfuric acid production system | |
| CN108793089B (en) | Process for producing refined sulfuric acid in sulfuric acid plant | |
| KR100534482B1 (en) | Regeneration method of waste etching solution | |
| CN112744788B (en) | Separation and purification method for deep dehydration and impurity removal of FTrPSA refined by anhydrous HF (hydrogen fluoride) produced by fluosilicic acid method | |
| CN115611403A (en) | Device and method for removing hydrogen peroxide in waste sulfuric acid | |
| CN214327178U (en) | Processing system of fluorine-containing nitric acid waste liquid |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C53 | Correction of patent for invention or patent application | ||
| CB03 | Change of inventor or designer information |
Inventor after: Li Shijiang Inventor after: Yang Shuiyan Inventor after: Liu Haixia Inventor after: Huangfu Genli Inventor after: Hou Hongjun Inventor after: Yang Huachun Inventor after: Xue Xujin Inventor after: Shang Zhongsheng Inventor after: Wang Hui Inventor after: Chen Dahong Inventor before: Huangfu Genli Inventor before: Li Shijiang Inventor before: Liu Haixia Inventor before: Liu Xiaoxia Inventor before: Zhang Liang |
|
| COR | Change of bibliographic data |
Free format text: CORRECT: INVENTOR; FROM: HUANGPU GENLI LI SHIJIANG LIU HAIXIA LIU XIAOXIA ZHANG LIANG TO: LI SHIJIANG LIU HAIXIA HUANGPU GENLI HOU HONGJUN YANG HUACHUN XUE XUJIN SHANG ZHONGSHENG WANG HUI CHEN DAHONG YANG SHUIYAN |
|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CP03 | Change of name, title or address |
Address after: 454191 Henan Province, Jiaozuo City Station area coke Rd Patentee after: Duofudo New Material Co.,Ltd. Address before: 454191, Feng County, Henan Province, Jiaozuo Feng Feng Chemical Industry Zone Patentee before: DO-FLUORIDE CHEMICALS Co.,Ltd. |
|
| CP03 | Change of name, title or address |