CN102139864A - Method for producing electronic-grade nitric acid - Google Patents
Method for producing electronic-grade nitric acid Download PDFInfo
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- CN102139864A CN102139864A CN 201110041529 CN201110041529A CN102139864A CN 102139864 A CN102139864 A CN 102139864A CN 201110041529 CN201110041529 CN 201110041529 CN 201110041529 A CN201110041529 A CN 201110041529A CN 102139864 A CN102139864 A CN 102139864A
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Abstract
The invention discloses a method for producing electronic-grade nitric acid. The method sequentially comprises the following steps of: a) providing a chemically pure reagent-grade nitric acid raw material of which the concentration is about 70 percent; b) performing microfiltration on the nitric acid raw material, adding the nitric acid raw material into a pre-heater for preheating, and adding into a reboiler; c) heating the reboiler with saturated vapor, and making nitric acid vapor generated by heating pass through a vapor condenser to obtain a semi-finished product; d) blowing the semi-finished product with high-purity compressed air to remove residual vapor in the semi-finished product, cooling the obtained finished product again with a finished product cooler, and adding the finished product into a finished product storage tank; and e) performing ultrafiltration on the finished product to remove particles so as to finally obtain the nitric acid applied in the electronic industry. In the method for producing the electronic-grade nitric acid, the normal chemically pure reagent-grade nitric acid raw material of which the concentration is about 70 percent is directly rectified and then the rectified product is blown with the high-purity compressed air. The used raw material is safe; the pressure for the subsequent tail gas treatment is greatly reduced; and the production cost is reduced.
Description
Technical field
The present invention relates to a kind of nitric acid preparation method, relate in particular to a kind of needed electronic-grade nitric acid preparation method of large-scale integrated circuit that is applied to.
Background technology
Nitric acid, relative molecular mass is 63.01, is a kind of mineral acid that strong oxidizing property, severe corrosive are arranged.Soluble in water, ionization fully in water, its dilute solution water white transparency under the normal temperature, it is brown that strong solution shows.The nitric acid instability is easily seen photolysis, can make oxidation operation or nitrated, and density when spending (25) is 1.42g/ml.Super-pure nitric acid is strongly-acid clean-out system and etching reagent, can be used with Glacial acetic acid, hydrogen peroxide, and the nitric acid of concentration about 70% is mainly used in the production of large-scale integrated circuit.
The preparation technology of super-pure nitric acid mainly contains sub-boiling distillation method, continuous rectification method etc.What application was many at present is the nitric acid product that obtains after the industrial concentrated acid process rectifying of employing concentration more than 95% about 95%, and then is diluted to the nitric acid of needed concentration about 70% with ultrapure water.And owing to when the dilute with water concentrated nitric acid, can produce a large amount of dissociating
, outward appearance is red-brown, therefore must adopt high-purity
With free
Remove, just can obtain colourless product.The shortcoming of this kind method is that it is free itself to contain small part in the concentrated nitric acid
, and during the dilute with water concentrated nitric acid because the heat release meeting produces a large amount of free
, must remove, traditional method adopts
Remove
Not only uneconomical, make troubles on the contrary follow-up vent gas treatment, in addition, because the severe corrosive and the unstable of concentrated nitric acid adopt 95% above concentrated nitric acid as raw material production, safety factors also needs to consider.
Summary of the invention
Technical problem to be solved by this invention provides a kind of electronic-grade nitric acid preparation method, and is with low cost, production safety and can realize successive scale operation.
The present invention solves the problems of the technologies described above the technical scheme that adopts to provide a kind of electronic-grade nitric acid preparation method, in turn includes the following steps: the chemically pure reagent level nitric acid material that concentration about 70% a) is provided; B) above-mentioned nitric acid material enters in the reboiler after entering the preheater preheating through micro-filtration; C) adopt saturation steam that reboiler is heated, the nitric acid vapor that adds thermogenesis obtains work in-process through behind the steam condenser; D) with high-purity pressurized air work in-process are purged again, remove in the work in-process residual
, resulting finished product enters the finished product storage tank after cooling off once more through the finished product water cooler; E) through obtaining the final nitric acid that is applied to electron trade behind the ultrafiltration removal particle.
Above-mentioned electronic-grade nitric acid preparation method, wherein, the filter core of micro-filtration adopts micron-sized PP material filter core in the described step b).
Above-mentioned electronic-grade nitric acid preparation method, wherein, the reboiler shell in the described step b) adopts the borosilicate glass material, and the inner bag well heater adopts pure tantalum material to make, and described saturated vapour pressure is 4.5～5.5MPa.
Above-mentioned electronic-grade nitric acid preparation method, wherein, the nitric acid vapor that reboiler comes out in the described step c) further improves nitric acid vapor purity through rectifying tower, and described rectifying tower adopts the borosilicate glass material, and PFA filler (soluble poly tetrafluoroethylene) is housed in the tower.
Above-mentioned electronic-grade nitric acid preparation method, wherein, the nitric acid vapor temperature that steam condenser comes out in the described step c) is about 120 ℃, through becoming the nitric acid liquid of temperature about 80-95 ℃ after the steam condenser condensation, obtains the nitric acid work in-process.
Above-mentioned electronic-grade nitric acid preparation method, wherein, work in-process in the described step d) purge the nitric acid finished product that can obtain after then process finished product water cooler further cools off under the normal temperature with pressurized air in deaeration tower, described deaeration tower adopts the borosilicate glass material, and the PFA filler is housed in the tower.
Above-mentioned electronic-grade nitric acid preparation method, wherein, the finished product storage tank in the described step d) adopts stainless steel lined fluorine material.
Above-mentioned electronic-grade nitric acid preparation method, wherein, the filter core of ultrafiltration is a submicron order perfluor material in the described step e).
Above-mentioned electronic-grade nitric acid preparation method, wherein, described preheater, steam condenser, finished product water cooler are made by borosilicate glass.
The present invention contrasts prior art following beneficial effect: electronic-grade nitric acid preparation method provided by the invention, and directly adopt the chemically pure reagent level nitric acid of common concentration about 70% to carry out rectifying, purge removal with high-purity pressurized air after the rectifying
, compare with existing technology, rare nitric acid than concentrated nitric acid as raw material safety, and free because of what itself contain in rare nitric acid
Less, add the technology of not using ultrapure water to absorb, but directly rectifying, so total produce free of production process
Less, for free
The removal method above, use high-purity pressurized air instead and come free
Purge a part
Change into
Enter finished product, not only carried out waste gas utilization well, and greatly reduced the pressure of follow-up vent gas treatment, the employing expense of therefore comparing is higher
Remove
, greatly reduced production cost.
?
Description of drawings
Fig. 1 is an electronic-grade nitric acid production plant synoptic diagram of the present invention;
Fig. 2 is an electronic-grade nitric acid preparation method schema of the present invention.
Among the figure:
1 raw material tank, 2 spent acid grooves, 3 preheaters
4 reboilers, 5 rectifying tower, 6 steam condensers
7 tail gas condensers, 8 deaeration towers, 9 finished product water coolers
10 finished product storage tanks
Embodiment
The invention will be further described below in conjunction with drawings and Examples.
Fig. 1 is an electronic-grade nitric acid production plant synoptic diagram of the present invention; Fig. 2 is an electronic-grade nitric acid preparation method schema of the present invention.
See also Fig. 1 and Fig. 2, electronic-grade nitric acid preparation method provided by the invention comprises the steps:
S1: the chemically pure reagent level nitric acid material of concentration about 70% is provided, and nitric acid material is stored in the stainless steel raw material tank 1;
S2: above-mentioned nitric acid material enters in the reboiler 4 after preheater 3 preheatings through the flow of micron-sized PP material filter element filtering with 120-180kg/h, preheater 3 is used for the nitric acid spent acid of normally discharging is carried out preheating to nitric acid material, reduced the use of heating agent so admirably, preheater is made by borosilicate glass; The spent acid that normally emits from feed preheater adopts spent acid groove 2 to take up, and storage tank adopts stainless steel;
S3: reboiler 4 shells adopt borosilicate glass to make, the inner bag well heater adopts pure tantalum material to make, saturation steam with 4.5-5.5MPa heats it, the flow control of saturation steam is between 100-150kg/h, and the nitric acid vapor that adds thermogenesis obtains 80-95 ℃ nitric acid work in-process through steam condenser 6 condensations; If needed, these work in-process can be back to rectifying tower by reflux line and carry out further purifying;
S4: the nitric acid work in-process purge through pressurized air in the deaeration tower 8, and the nitric acid behind the purging is again through obtaining the normal temperature nitric acid product of 100-160kg/h after 9 coolings of finished product water cooler, and finished product nitric acid is collected in the finished product storage tank 10 that stainless steel lined fluorine material makes;
S5: the nitric acid finished product obtains final qualified product through behind the submicron order filter element filtering of full tetrafluoro material again.
The nitric acid technical target of the product that obtains sees the following form:
As seen from the above table, single metal ion content＜1ppb in the nitric acid that explained hereafter of the present invention obtains, single anion-content＜100ppb is greater than particle＜5 of 0.5um/milliliter.
In sum, electronic-grade nitric acid preparation method technology provided by the invention is easy, and production cost is low, and is easy to operate, the product purity height, and impurity ion content is low, can be applied to the production of large-scale integrated circuit.Because nitric acid and water are azeotropes between concentration of nitric acid 69%-72%, the present invention purifies to it by the method for the rare nitric acid of simple distillation, more complicated high density nitric acid is not distilled the technology that then absorbs with ultrapure water and do not need to adopt, in addition, adopt high-purity pressurized air right
Purge, can avoid using more expensive on the one hand
, should be in the high pure air again on the other hand
Can follow
Reacting and produce nitric acid, so can be to need the waste gas handled originally
Change into final nitric acid product, greatly reduced the production technique cost.Concrete advantage is as follows: 1, directly adopt the chemically pure reagent level nitric acid of common concentration about 70% to purify again, need not the technology that adopts the distillation concentrated nitric acid to absorb with ultrapure water; 2, adopt borosilicate glass equipment to carry out purifying, guaranteed the quality and the purity of product; 3, the present invention adopts high-purity pressurized air in the nitric acid
Purge, compare and adopt high pure nitrogen, the recyclable tail gas that utilizes, and can greatly reduce the production run cost; 4, the present invention adopts the nitric acid of the heat of ordinary production discharging that cold nitric acid material is carried out preheating, has so reduced the use of heating agent steam, has reduced the production run cost; 5, the present invention collects the spent acid of producing, and avoids direct emission treatment, and the spent acid of collection can be transferred to the material supplier and reclaim or can be used as the byproduct sale, if both reduced the expense of environmental protection treatment, can increase the operation revenue of a part again.
Though the present invention discloses as above with preferred embodiment; right its is not in order to qualification the present invention, any those skilled in the art, without departing from the spirit and scope of the present invention; when can doing a little modification and perfect, so protection scope of the present invention is when with being as the criterion that claims were defined.
Claims (9)
1. an electronic-grade nitric acid preparation method is characterized in that, described method in turn includes the following steps:
A) provide the chemically pure reagent level nitric acid material of concentration about 70%;
B) above-mentioned nitric acid material enters in the reboiler after entering the preheater preheating through micro-filtration;
C) adopt saturation steam that reboiler is heated, the nitric acid vapor that adds thermogenesis obtains work in-process through behind the steam condenser;
D) with high-purity pressurized air work in-process are purged again, remove in the work in-process residual
, resulting finished product enters the finished product storage tank after cooling off once more through the finished product water cooler;
E) through obtaining the final nitric acid that is applied to electron trade behind the ultrafiltration removal particle.
2. electronic-grade nitric acid preparation method as claimed in claim 1 is characterized in that, the filter core of micro-filtration adopts micron-sized PP material filter core in the described step b).
3. electronic-grade nitric acid preparation method as claimed in claim 1 is characterized in that, the reboiler shell in the described step b) adopts the borosilicate glass material, and the inner bag well heater adopts pure tantalum material to make, and described saturated vapour pressure is 4.5～5.5MPa.
4. electronic-grade nitric acid preparation method as claimed in claim 1 is characterized in that, the nitric acid vapor that reboiler comes out in the described step c) further improves nitric acid vapor purity through rectifying tower, and described rectifying tower adopts the borosilicate glass material, and the PFA filler is housed in the tower.
5. electronic-grade nitric acid preparation method as claimed in claim 1 is characterized in that, the nitric acid fluid temperature that steam condenser comes out in the described step c) is 80-95 ℃.
6. electronic-grade nitric acid preparation method as claimed in claim 1, it is characterized in that, work in-process in the described step d) purge then through obtaining the nitric acid finished product under the normal temperature after the further cooling of finished product water cooler with pressurized air in deaeration tower, described deaeration tower adopts the borosilicate glass material, and the PFA filler is housed in the tower.
7. electronic-grade nitric acid preparation method as claimed in claim 1 is characterized in that, the finished product storage tank in the described step d) adopts stainless steel lined fluorine material.
8. electronic-grade nitric acid preparation method as claimed in claim 1 is characterized in that, the filter core of ultrafiltration is the full tetrafluoro material of submicron order in the described step e).
9. as each described electronic-grade nitric acid preparation method of claim 1～8, it is characterized in that described preheater, steam condenser, finished product water cooler are made by borosilicate glass.
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| CN 201110041529 CN102139864B (en) | 2011-02-21 | 2011-02-21 | Method for producing electronic-grade nitric acid |
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|---|---|---|---|
| CN 201110041529 CN102139864B (en) | 2011-02-21 | 2011-02-21 | Method for producing electronic-grade nitric acid |
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| CN102139864B CN102139864B (en) | 2013-01-23 |
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Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103072962A (en) * | 2011-10-26 | 2013-05-01 | 上海巴斯夫聚氨酯有限公司 | Preparation method of electronic grade nitric acid |
| CN103359698A (en) * | 2013-07-30 | 2013-10-23 | 江阴江化微电子材料股份有限公司 | Purification system for industrial production of electronic grade nitric acid |
| CN103523761A (en) * | 2013-10-15 | 2014-01-22 | 苏州市晶协高新电子材料有限公司 | Continuous nitric acid discoloring device and method thereof |
| CN104108690A (en) * | 2014-06-11 | 2014-10-22 | 苏州市晶协高新电子材料有限公司 | Equipment and process for preparing electronic grade nitric acid having a concentration of 68% from industrial grade nitric acid having a concentration of 98% |
| CN111960393A (en) * | 2020-08-26 | 2020-11-20 | 浙江凯圣氟化学有限公司 | Preparation method of nitric acid without yellow smoke |
| CN112279225A (en) * | 2020-11-16 | 2021-01-29 | 河南骏化发展股份有限公司 | Production system and process for co-production of industrial-grade nitric acid and electronic-grade nitric acid |
| CN112591722A (en) * | 2020-12-16 | 2021-04-02 | 四川金象赛瑞化工股份有限公司 | Method for co-producing industrial-grade nitric acid and electronic-grade nitric acid |
| CN113233434A (en) * | 2021-07-13 | 2021-08-10 | 联仕(昆山)化学材料有限公司 | Production process and production device of electronic-grade nitric acid |
| CN113353900A (en) * | 2021-08-10 | 2021-09-07 | 联仕(昆山)化学材料有限公司 | Electronic-grade nitric acid preparation device |
| CN113880058A (en) * | 2021-10-28 | 2022-01-04 | 河南省氟基新材料科技有限公司 | Purification method of industrial-grade nitric acid |
| CN114014282A (en) * | 2022-01-05 | 2022-02-08 | 苏州香榭轩表面工程技术咨询有限公司 | Continuous production method of high-purity nitric acid |
| CN115028147A (en) * | 2022-06-30 | 2022-09-09 | 江苏淮河化工有限公司 | Process for continuously preparing electronic-grade nitric acid by rectification and stripping integrated method |
| CN115417389A (en) * | 2022-10-13 | 2022-12-02 | 成都市科隆化学品有限公司 | Multi-level high-purity nitric acid co-production system and co-production method thereof |
| WO2023015603A1 (en) * | 2021-08-09 | 2023-02-16 | 联仕(昆山)化学材料有限公司 | Electronic-grade nitric acid production process |
| CN116374967A (en) * | 2023-04-17 | 2023-07-04 | 四川金象赛瑞化工股份有限公司 | Preparation process of high-purity nitric acid |
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Cited By (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103072962A (en) * | 2011-10-26 | 2013-05-01 | 上海巴斯夫聚氨酯有限公司 | Preparation method of electronic grade nitric acid |
| CN103359698A (en) * | 2013-07-30 | 2013-10-23 | 江阴江化微电子材料股份有限公司 | Purification system for industrial production of electronic grade nitric acid |
| CN103359698B (en) * | 2013-07-30 | 2015-02-18 | 江阴江化微电子材料股份有限公司 | Purification system for industrial production of electronic grade nitric acid |
| CN103523761A (en) * | 2013-10-15 | 2014-01-22 | 苏州市晶协高新电子材料有限公司 | Continuous nitric acid discoloring device and method thereof |
| CN103523761B (en) * | 2013-10-15 | 2015-08-05 | 苏州市晶协高新电子材料有限公司 | A kind of nitric acid continuous stripping devices and methods therefor |
| CN104108690A (en) * | 2014-06-11 | 2014-10-22 | 苏州市晶协高新电子材料有限公司 | Equipment and process for preparing electronic grade nitric acid having a concentration of 68% from industrial grade nitric acid having a concentration of 98% |
| CN104108690B (en) * | 2014-06-11 | 2016-06-15 | 苏州市晶协高新电子材料有限公司 | Equipment and the technique of electron level 68% nitric acid is prepared by 98% technical grade nitric acid |
| CN111960393A (en) * | 2020-08-26 | 2020-11-20 | 浙江凯圣氟化学有限公司 | Preparation method of nitric acid without yellow smoke |
| CN112279225A (en) * | 2020-11-16 | 2021-01-29 | 河南骏化发展股份有限公司 | Production system and process for co-production of industrial-grade nitric acid and electronic-grade nitric acid |
| CN112591722A (en) * | 2020-12-16 | 2021-04-02 | 四川金象赛瑞化工股份有限公司 | Method for co-producing industrial-grade nitric acid and electronic-grade nitric acid |
| CN113233434A (en) * | 2021-07-13 | 2021-08-10 | 联仕(昆山)化学材料有限公司 | Production process and production device of electronic-grade nitric acid |
| WO2023015603A1 (en) * | 2021-08-09 | 2023-02-16 | 联仕(昆山)化学材料有限公司 | Electronic-grade nitric acid production process |
| CN113353900A (en) * | 2021-08-10 | 2021-09-07 | 联仕(昆山)化学材料有限公司 | Electronic-grade nitric acid preparation device |
| CN113880058A (en) * | 2021-10-28 | 2022-01-04 | 河南省氟基新材料科技有限公司 | Purification method of industrial-grade nitric acid |
| CN114014282A (en) * | 2022-01-05 | 2022-02-08 | 苏州香榭轩表面工程技术咨询有限公司 | Continuous production method of high-purity nitric acid |
| CN114014282B (en) * | 2022-01-05 | 2022-04-01 | 苏州香榭轩表面工程技术咨询有限公司 | Continuous production method of high-purity nitric acid |
| CN115028147A (en) * | 2022-06-30 | 2022-09-09 | 江苏淮河化工有限公司 | Process for continuously preparing electronic-grade nitric acid by rectification and stripping integrated method |
| CN115417389A (en) * | 2022-10-13 | 2022-12-02 | 成都市科隆化学品有限公司 | Multi-level high-purity nitric acid co-production system and co-production method thereof |
| CN116374967A (en) * | 2023-04-17 | 2023-07-04 | 四川金象赛瑞化工股份有限公司 | Preparation process of high-purity nitric acid |
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