CN105523570A - Preparation method of ppt-scale ultrapure ammonium hydroxide - Google Patents
Preparation method of ppt-scale ultrapure ammonium hydroxide Download PDFInfo
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- CN105523570A CN105523570A CN201610086184.7A CN201610086184A CN105523570A CN 105523570 A CN105523570 A CN 105523570A CN 201610086184 A CN201610086184 A CN 201610086184A CN 105523570 A CN105523570 A CN 105523570A
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01C—AMMONIA; CYANOGEN; COMPOUNDS THEREOF
- C01C1/00—Ammonia; Compounds thereof
- C01C1/02—Preparation, purification or separation of ammonia
- C01C1/024—Purification
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01C—AMMONIA; CYANOGEN; COMPOUNDS THEREOF
- C01C1/00—Ammonia; Compounds thereof
- C01C1/02—Preparation, purification or separation of ammonia
- C01C1/022—Preparation of aqueous ammonia solutions, i.e. ammonia water
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Abstract
The invention discloses a preparation method of ppt-scale ultrapure ammonium hydroxide. The preparation method comprises the following steps which are performed sequentially and continuously: (1) vaporization; (2) purifying filtration; (3) resin adsorption; (4) washing; (5) water-gas separation; (6) multistage absorption; (7) ultrafiltration. For ultrapure ammonium hydroxide prepared with the method, the concentration of particles larger than or equal to 0.5 mu m is smaller than 3 p/ml, the concentration of particles larger than or equal to 0.2 mu m is smaller than 30 p/ml, and the content of single metal ions is smaller than 30 ppt and is proved to be smaller than 20 ppt through actual measurement. The preparation method of ppt-scale ultrapure ammonium hydroxide is simple in technological process and easy to realize, pure ammonium hydroxide is obtained firstly with a reasonable impurity removal process, then ppt-scale ultrapure ammonium hydroxide is obtained through multistage absorption with ultrapure water, a few devices are used for the preparation method, the operation is easy, and the production cost is low.
Description
Technical field
The present invention relates to super-clean high-pure electronic chemical technical field, particularly relate to a kind of preparation method of PPT level super-pure ammonia water.
Background technology
In semicon industry, in pure semiconductor product, mix the impurity element of denier, will make the resistivity of product that change greatly occurs.Such as, in pure boron, mix 1,000,000/-boron, its resistivity will be reduced to 0.4 Ω cm from 214000 Ω cm quickly, and namely the conduction of boron can for improve more than 50 ten thousand times.As can be seen here, semicon industry requires high to the purity of chemical material.
Super-pure ammonia water is one of eight large ultrapure chemical materials that semicon industry is conventional, and consumption occupies IC industry the 3rd, is mainly used in the technique such as the diffusion of silicon wafer, burn into cleaning.The purity of the ultra pure chemicals used in chip technology and cleanliness factor have very important impact to the yield rate of unicircuit (IC), electrical property and reliability.
At present, domestic production manufacturer has techniques such as adopting batch fractionating method, membrane filtration absorption process, resin filter method to prepare high-purity ammonia water, there is technical process complexity to a certain extent in these methods, soak time is longer, the defects such as equipment configuration is more, in the ammoniacal liquor obtained, foreign matter content is still higher, and still effectively can not remove the obstinate boron impurities element in ammoniacal liquor.
Summary of the invention
The technical problem that the present invention mainly solves is to provide a kind of preparation method of PPT level super-pure ammonia water, effectively can solve existing high-purity ammonia water and produce the problems referred to above existed, prepare the ammoniacal liquor that product purity is higher.
For solving the problems of the technologies described above, the technical scheme that the present invention adopts is: the preparation method providing a kind of PPT level super-pure ammonia water, comprises successively and the following steps of carrying out continuously:
(1) vaporize: utilize compressor by liquid ammonia from head tank force feed to vaporizer in utilize hot steam evaporate become ammonia;
(2) purification filtering: the ammonia after the ammonia after vaporization in step (1) is purified by draining separator and activated carbon adsorption device successively;
(3) resin absorption: the ammonia after purification filtering in step (2) is adsorbed oil removal treatment through polymeric adsorbent;
(4) wash: the ammonia after resin absorption in step (3) is spent ultrapure water and saturated ammonia water washing removal of impurities;
(5) aqueous vapor is separated: the ammonia moisture separator after washing impurity-removing in step (4) is separated into aqueous vapor and ammonia;
(6) multistage absorption: the ammonia after aqueous vapor in step (5) being separated by absorption tower, and carries out multistage absorption with ultrapure water, forms ammoniacal liquor;
(7) ultrafiltration: the ammoniacal liquor obtained in step (6) is carried out uf processing, obtains described PPT level super-pure ammonia water.
In a preferred embodiment of the present invention, described preparation method also comprises that the ammoniacal liquor after by multistage absorption first carries out lowering the temperature through cooling apparatus, step-down process, then carries out the uf processing of step (7); Ammonia temperature after described cooling apparatus process is less than 20 DEG C, and pressure is less than 0.1MPa.
In a preferred embodiment of the present invention, in described step (1), described vaporizer is partition heat-exchanging decompression evaporation device, and its liner material is PFA material.
In a preferred embodiment of the present invention, in described step (3), described polymeric adsorbent is polystyrene adsorption resin.
In a preferred embodiment of the present invention, the aperture of described polymeric adsorbent is 0.005 ~ 0.01 μm.
In a preferred embodiment of the present invention, in described step (6), described ultrapure resistivity of water is greater than 18.2M Ω cm.
In a preferred embodiment of the present invention, described ultrapure water is without boron ultrapure water.
In a preferred embodiment of the present invention, the liner on described moisture separator and absorption tower is PFA material, and wherein, described absorption tower is mono-tower multi-stage absorption tower.
In a preferred embodiment of the present invention, in described PPT level super-pure ammonia water, be more than or equal to 0.5 μm of granule density and be less than 3p/ml, be more than or equal to 0.2 μm of granule density and be less than 30p/ml, individual event metal ion content is less than 30ppt.
The invention has the beneficial effects as follows: the preparation method of a kind of PPT level of the present invention super-pure ammonia water, technical process is simple, easy realization, it is first by rational impurity removal process, obtain pure ammonia, then obtain ppt level super-pure ammonia water by ultrapure water multistage absorption, and this preparation method's equipment used is few, easy handling, production cost is low.
Accompanying drawing explanation
Fig. 1 is the schematic flow sheet of the preparation method of a kind of PPT level of the present invention super-pure ammonia water;
Fig. 2 is the connection diagram of shown production unit;
In accompanying drawing, the mark of each parts is as follows: 1. head tank, 2. vaporizer, 3. hot-water cylinder, 4. draining separator, 5. active carbon adsorber, 6. strainer, 7. washing tower, 8. the first condenser, 9. moisture separator, 10. absorption tower, 11. second condensers, 12. cycle condensers, 13. storage tanks.
Embodiment
Below in conjunction with accompanying drawing, preferred embodiment of the present invention is described in detail, can be easier to make advantages and features of the invention be readily appreciated by one skilled in the art, thus more explicit defining is made to protection scope of the present invention.
Refer to Fig. 1 and Fig. 2, the embodiment of the present invention comprises:
The preparation method of a kind of PPT level of the present invention super-pure ammonia water, comprises successively and the following steps of carrying out continuously:
(1) vaporize: take industrial liquid ammonia as raw material, utilize compressor by liquid ammonia from force feed in head tank 1 in vaporizer 2, this vaporizer is the partition heat-exchanging decompression evaporation device containing snakelike heat exchange tube, its liner material is PFA, it is communicated with hot-water cylinder 3 by hot water cyclesystem, and as thermal source in the heat transfer tube hot steam in hot-water cylinder 3 being passed into vaporizer, make liquefied ammonia be evaporated to ammonia;
(2) purification filtering: the ammonia after gasification in step (1) removes moisture and oil content by being separated with the draining separator 4 that vaporizer 2 is communicated with, and then passes into activated carbon adsorption device 5, removes graininess impurity, pigment etc.;
(3) resin absorption: the ammonia after purification filtering in step (2) is carried out absorption oil removal treatment, the ammonia after being purified by the strainer 6 being filled with polymeric adsorbent; Wherein, described polymeric adsorbent is polystyrene adsorption resin, and its aperture is 0.005 ~ 0.01 μm;
(4) wash: the ammonia after resin absorption in step (3) is passed in washing tower 7 and uses ultrapure water and saturated ammonia water washing, to remove gritty particle further, and form the ammoniacal liquor that mass concentration is 20 ~ 25%; This washing tower liner is PFA material, and is communicated with the first condenser 8, for carrying out condensation step-down process to ammonia;
(5) aqueous vapor is separated: the moisture separator 9 being PFA material by the ammoniacal liquor liner after washing impurity-removing in step (4) is separated into aqueous vapor and ammonia;
(6) multistage absorption: the ammonia after aqueous vapor in step (5) being separated by absorption tower 10, and carries out multistage absorption with the ultrapure water that resistivity is greater than 18.2M Ω cm, forms ammoniacal liquor; Wherein, this absorption tower 10 is the mono-tower multi-stage absorption tower of PFA liner;
(7) lower the temperature, step-down process: first carried out lowering the temperature through the second condenser 11 and cycle condenser 12 by the ammoniacal liquor after multistage absorption, step-down process, formation temperature is less than 20 DEG C, and pressure is less than the ammoniacal liquor of 0.1MPa;
(8) ultrafiltration: the ammoniacal liquor obtained in step (6) is carried out uf processing, and stored in storage tank 13, obtain described super-pure ammonia water, in this super-pure ammonia water, be more than or equal to 0.5 μm of granule density and be less than 3p/ml, be more than or equal to 0.2 μm of granule density and be less than 30p/ml, individual event metal ion content is less than 30ppt, and actual measurement is less than 20ppt.
Embodiment 2
Be with the difference of embodiment 1, described ultrapure water is without boron ultrapure water.This preparation method without boron ultrapure water is: on the basis of existing ultrapure water, by carrying out except boron except boron technique; Described boron technique of removing comprises polyhydric alcohol complex reverse osmosis except boron and two-stage effects of boron resin are except boron.
Wherein, the concrete grammar that polyhydric alcohol complex reverse osmosis removes boron is: in tap water, add dilute hydrochloric acid, its pH value is regulated to be 3 ~ 6.5, then the polyvalent alcohol adding 1 ~ 10ppm in often liter of tap water (comprises D-glucitol, N.F,USP MANNITOL, at least one in D-Fructose and Xylitol), after stirring, boric acid in polyvalent alcohol and tap water forms macromolecular complex compound, and then the tap water this being contained macromolecular complex thing introduces reverse osmosis unit with certain pressure, remove macromolecular complex thing, thus realize the object removing boron, the clearance of the method boric acid is 80%.
Two-stage effects of boron resin is except boron, concrete grammar is: introduce one-level effects of boron resin by removing the tap water after boron through polyhydric alcohol complex reverse osmosis, for gallic acid grafting strong acid cation ion exchange resin, constant temperature stirs 20 ~ 60min, resin is made fully to adsorb boric acid in tap water, realize water body is except the object of boron from the beginning, resolved by the one-level effects of boron resin after absorption, this process can remove the boron of in tap water more than 95% simultaneously; Then adding diluted sodium hydroxide solution regulates the pH value of tap water to be 8.5 ~ 9.5, introduce secondary effects of boron resin again, be 2,3-dihydroxyl-6-sodium sulfonate grafting strongly basic anion exchange resin, constant temperature stirs 20 ~ 60min, makes resin fully adsorb boric acid in water body from the beginning, realizes water body from the beginning except the object of boron, resolved by secondary effects of boron resin after absorption, this process can remove borons whole in tap water simultaneously.
Above-mentioned super-pure ammonia water detects acquired results as following table:
The foregoing is only embodiments of the invention; not thereby the scope of the claims of the present invention is limited; every utilize specification sheets of the present invention and accompanying drawing content to do equivalent structure or equivalent flow process conversion; or be directly or indirectly used in other relevant technical fields, be all in like manner included in scope of patent protection of the present invention.
Claims (9)
1. a preparation method for PPT level super-pure ammonia water, is characterized in that, comprises successively and the following steps of carrying out continuously:
(1) vaporize: utilize compressor by liquid ammonia from head tank force feed to vaporizer in utilize hot steam evaporate become ammonia;
(2) purification filtering: the ammonia after the ammonia after vaporization in step (1) is purified by draining separator and activated carbon adsorption device successively;
(3) resin absorption: the ammonia after purification filtering in step (2) is adsorbed oil removal treatment through polymeric adsorbent;
(4) wash: by the ammonia ultrapure water after resin absorption in step (3) and saturated ammonia water washing removal of impurities;
(5) aqueous vapor is separated: the ammonia moisture separator after washing impurity-removing in step (4) is separated into aqueous vapor and ammonia;
(6) multistage absorption: the ammonia after aqueous vapor in step (5) being separated by absorption tower, and carries out multistage absorption with ultrapure water, forms ammoniacal liquor;
(7) ultrafiltration: the ammoniacal liquor obtained in step (6) is carried out uf processing, obtains described PPT level super-pure ammonia water.
2. the preparation method of super-pure ammonia water according to claim 1, is characterized in that, described preparation method also comprises that the ammoniacal liquor after by multistage absorption first carries out lowering the temperature through cooling apparatus, step-down process, then carries out the uf processing of step (7); Ammonia temperature after described cooling apparatus process is less than 20 DEG C, and pressure is less than 0.1MPa.
3. the preparation method of super-pure ammonia water according to claim 1, is characterized in that, in described step (1), described vaporizer is partition heat-exchanging decompression evaporation device, and its liner material is PFA material.
4. the preparation method of super-pure ammonia water according to claim 1, is characterized in that, in described step (3), described polymeric adsorbent is polystyrene adsorption resin.
5. the preparation method of super-pure ammonia water according to claim 4, is characterized in that, the aperture of described polymeric adsorbent is 0.005 ~ 0.01 μm.
6. the preparation method of super-pure ammonia water according to claim 1, is characterized in that, in described step (6), described ultrapure resistivity of water is greater than 18.2M Ω cm.
7. the preparation method of super-pure ammonia water according to claim 6, is characterized in that, described ultrapure water is without boron ultrapure water.
8. the preparation method of super-pure ammonia water according to claim 1, is characterized in that, the liner on described moisture separator and absorption tower is PFA material, and wherein, described absorption tower is mono-tower multi-stage absorption tower.
9. the preparation method of super-pure ammonia water according to claim 1, it is characterized in that, in described PPT level super-pure ammonia water, be more than or equal to 0.5 μm of granule density and be less than 3p/ml, be more than or equal to 0.2 μm of granule density and be less than 30p/ml, individual event metal ion content is less than 30ppt.
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106315618A (en) * | 2016-09-22 | 2017-01-11 | 江苏中德电子材料科技有限公司 | Ultra-clean high-purity ammonia water continuous production system |
| CN106629773A (en) * | 2016-09-22 | 2017-05-10 | 江苏中德电子材料科技有限公司 | Energy-saving continuous ultra-clean high-purity ammonium hydroxide production system |
| CN107416862A (en) * | 2017-08-09 | 2017-12-01 | 山西华晨昊环保科技有限公司 | A kind of technique of purified industrial by-product ammoniacal liquor |
| CN109850917A (en) * | 2018-12-26 | 2019-06-07 | 江苏达诺尔科技股份有限公司 | A kind of preparation method of efficient low-consume PPT grades of high-purity ammonia waters |
| CN110671603A (en) * | 2018-07-03 | 2020-01-10 | 山东恒昌圣诚化工股份有限公司 | External heating type solid ammonia filling device |
| CN110671602A (en) * | 2018-07-03 | 2020-01-10 | 山东恒昌圣诚化工股份有限公司 | Self-heating type solid ammonia filling device |
| CN111102469A (en) * | 2018-10-25 | 2020-05-05 | 山东恒昌圣诚化工股份有限公司 | Self-heating type solid ammonia filling device and filling process |
| CN112279271A (en) * | 2020-11-16 | 2021-01-29 | 河南骏化发展股份有限公司 | Device and process for producing electronic-grade ammonia water by using purge gas of synthetic ammonia |
| CN113603112A (en) * | 2021-08-23 | 2021-11-05 | 联仕(昆山)化学材料有限公司 | Device for preparing electronic-grade ammonia water and preparation process thereof |
| CN115521006A (en) * | 2022-06-27 | 2022-12-27 | 江苏达诺尔科技股份有限公司 | Method for effectively improving ammonia water through demulsifier |
| CN117582781A (en) * | 2024-01-17 | 2024-02-23 | 联仕新材料(苏州)股份有限公司 | Electronic grade ammonia water preparation device and preparation method thereof |
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Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106315618A (en) * | 2016-09-22 | 2017-01-11 | 江苏中德电子材料科技有限公司 | Ultra-clean high-purity ammonia water continuous production system |
| CN106629773A (en) * | 2016-09-22 | 2017-05-10 | 江苏中德电子材料科技有限公司 | Energy-saving continuous ultra-clean high-purity ammonium hydroxide production system |
| CN106315618B (en) * | 2016-09-22 | 2018-08-03 | 江苏中德电子材料科技有限公司 | A kind of ultra-clean high-purity ammonium hydroxide continuous process system |
| CN107416862A (en) * | 2017-08-09 | 2017-12-01 | 山西华晨昊环保科技有限公司 | A kind of technique of purified industrial by-product ammoniacal liquor |
| CN110671602A (en) * | 2018-07-03 | 2020-01-10 | 山东恒昌圣诚化工股份有限公司 | Self-heating type solid ammonia filling device |
| CN110671603A (en) * | 2018-07-03 | 2020-01-10 | 山东恒昌圣诚化工股份有限公司 | External heating type solid ammonia filling device |
| CN111102469A (en) * | 2018-10-25 | 2020-05-05 | 山东恒昌圣诚化工股份有限公司 | Self-heating type solid ammonia filling device and filling process |
| CN109850917A (en) * | 2018-12-26 | 2019-06-07 | 江苏达诺尔科技股份有限公司 | A kind of preparation method of efficient low-consume PPT grades of high-purity ammonia waters |
| CN112279271A (en) * | 2020-11-16 | 2021-01-29 | 河南骏化发展股份有限公司 | Device and process for producing electronic-grade ammonia water by using purge gas of synthetic ammonia |
| CN113603112A (en) * | 2021-08-23 | 2021-11-05 | 联仕(昆山)化学材料有限公司 | Device for preparing electronic-grade ammonia water and preparation process thereof |
| CN115521006A (en) * | 2022-06-27 | 2022-12-27 | 江苏达诺尔科技股份有限公司 | Method for effectively improving ammonia water through demulsifier |
| CN115521006B (en) * | 2022-06-27 | 2024-05-24 | 江苏达诺尔科技股份有限公司 | Method for effectively improving ammonia water purity through demulsifier |
| CN117582781A (en) * | 2024-01-17 | 2024-02-23 | 联仕新材料(苏州)股份有限公司 | Electronic grade ammonia water preparation device and preparation method thereof |
| CN117582781B (en) * | 2024-01-17 | 2024-05-17 | 联仕新材料(苏州)股份有限公司 | Electronic grade ammonia water preparation device and preparation method thereof |
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Application publication date: 20160427 |