CN103387211A - Method for preparing electronic grade high-purity hydrogen chloride from industrially synthesized hydrogen chloride - Google Patents
Method for preparing electronic grade high-purity hydrogen chloride from industrially synthesized hydrogen chloride Download PDFInfo
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Abstract
The invention discloses a method for preparing electronic grade high-purity chlorine gas from industrial liquid chlorine. The method comprises the steps of: gasifying the industrial liquid chlorine, then performing multistage physical drying, adsorbing and removing carbon dioxide, performing compression-condensation, and rectifying for removing such gas with low boiling point as nitrogen gas, oxygen gas, hydrogen gas, carbon monoxide, methane and the like, thus obtaining the electronic grade high-purity chlorine gas with purity being over 99.999%. The method is low in cost and high in benefit, and products prepared by the method are high in purity and can be widely used for preparation of optical-fiber-communication, microelectronic and high-temperature superconducting materials.
Description
Technical field
The present invention relates to a kind of preparation method of electronic grade high-purity hydrogenchloride, particularly a kind of method for preparing electronic grade high-purity hydrogenchloride take industrial synthesising hydrogen as feed purification.
Background technology
Electronic grade high-purity hydrogenchloride is the important materials of the techniques such as silicon chip etching during unicircuit is produced, passivation, extension, gas phase polishing, gettering and clean processing, also can be used for the fields such as Metal smelting, optical communications and scientific research.Development along with large-scale integrated circuit, requirement to hydrogenchloride purity is more and more higher, except having the purity more than 99.999%, content requirement to impurity wherein is more and more harsher, the content of especially strict limiting carbon hydrogen compound and hydrocarbon, to prevent the formation of C in silicon chip working process.Past, China was mostly from state's Imported Electronic level hydrogenchloride such as U.S., days, but in recent years, the development of the chemical gas that China's electronic industry is required, existing many breakthrough and development technically.Domestic also have unit develop go out relevant electronic grade hydrogen chloride product, but also far can not meet the need of market.
Summary of the invention
The objective of the invention is to overcome the deficiencies in the prior art, a kind of method for preparing electronic grade high-purity hydrogenchloride take industrial synthesising hydrogen as feed purification is provided.
For achieving the above object, the present invention takes following technical proposals to realize:
A kind of method for preparing electronic grade high-purity hydrogenchloride take industrial synthesising hydrogen as raw material comprises the following steps:
A. after primary industry hydrogenchloride compresses after filtration, from the one-level drying tower bottom that siccative is housed, enter, after the adsorbing and removing most of moisture from tower top out;
B. enter again the secondary drying tower bottom that siccative is housed,, through deep dehydration, remove after micro-moisture from tower top out, remove moisture content in post chlorization hydrogen less than 0.5ppm;
C. then from the adsorption tower bottom that sorbent material is housed, enter, after adsorbing and removing carbonic acid gas and denier moisture, from tower top out, after absorption, carbon dioxide content is less than 2ppm;
D. pressurization, enter after condensation and take off light rectifying tower, nitrogen, oxygen, hydrogen, carbon monoxide, the low-boiling point gas such as methane are discharged from tower top, form tail gas and reclaim, remove rear a nitrogen content less than 2ppm, oxygen content is less than 1ppm, and carbon monoxide content is less than 1ppm, and methane is less than 1ppm;
E. enter and take off heavy rectifying tower from taking off at the bottom of light rectifying tower out hydrogenchloride liquid, vaporization removes the high boiling component heavier than hydrogenchloride;
F. eject the high-purity hydrogen chloride purity of coming and reach more than 99.999% from taking off heavy rectifying tower, compressed bulking system bottling, the high-purity hydrogen chloride after bottling, the metal ion total content is less than 0.3ppm.
Further, can also be provided with multistage physical dryness after step b.
Further, the siccative in step a and step b is zeolite molecular sieve.
Preferably, the siccative in step a and step b is the 13X zeolite molecular sieve.
Further, the sorbent material in step c is zeolite molecular sieve.
Preferably, the sorbent material in step c is the SSZ-13 zeolite molecular sieve.
Preferably, the siccative in step a and step b, the sorbent material in step c are all through 200 ℃ of high-temperature chlorine gas disposals two hours.
Further, after step a Raw industry synthesising hydrogen compresses after filtration, under the pressure and normal temperature of 0.3-0.6MP, with 1-5M
3The flow of/h enters the one-level drying tower.
Further, in steps d hydrogenchloride from adsorption tower out after, be compressed to 1.5-2.5MP, be cooled to-15 ℃--25 ℃.
Preferably, in steps d hydrogenchloride from adsorption tower out after, be compressed to 2.0MP, be cooled to-20 ℃.
The present invention has following technique effect: removed low-boiling point gas and the micro-high boiling material heavier than hydrogenchloride such as nitrogen, oxygen, hydrogen, carbon monoxide, methane by industrial synthesising hydrogen through multistage physical dryness, adsorbing and removing carbonic acid gas, compression condensation, rectifying, make the electronic grade high-purity hydrogenchloride more than 99.999%.This preparation method's cost is low, and income is high, and the product purity that makes is high, and product can be widely used in a plurality of public goods in unicircuit production, also can be used for Metal smelting, other field of scientific studies such as optical communications.
Further, water content and product purity requirement according to the different material product, can arrange multistage physical dryness, fully removes the moisture in raw material.
Further, siccative of the present invention can be used the model zeolite molecular sieves such as 3A, 5A, 13X, preferred 13X molecular sieve desiccant, this siccative does not react with hydrogenchloride, and water-retaining capacity is large, and possesses enough intensity, and can not bring metal ion and dust into to hydrogen chloride gas, easily regeneration.
Further, sorbent material can adopt the sorbent materials such as 5A, 13X, SSZ-13 zeolite molecular sieve, preferred SSZ-13 zeolite molecular sieve, and SSZ-13 is good to the carbonic acid gas absorption property, easily regeneration.
Further, siccative used in the present invention and sorbent material are all through 200 ℃ of high-temperature chlorine gas disposals 2 hours, and after processing, the dust rate reduces, and intensity enhancing can meet dry and the absorption requirement.
Description of drawings
Fig. 1 is process flow sheet in the embodiment of the present invention 1.
Embodiment
The present invention will be described in detail below in conjunction with drawings and Examples.
Embodiment 1:
Fig. 1 is preparation method's of the present invention process flow sheet.As shown in Figure 1, preparation method of the present invention comprises the following steps:
A. primary industry hydrogenchloride removes mechanical impurity more after compression after filtration, under the pressure of 0.4MP and normal temperature with 1 M
3The flow of/h enters from one-level drying tower 1 bottom of 13X type zeolite molecular sieve that numbering DH05 is housed, after the adsorbing and removing most of moisture from tower top out;
B. enter again the secondary drying tower bottom of 13X type zeolite molecular sieve that numbering DH06 is housed,, through deep dehydration, remove after micro-moisture from tower top out, remove moisture content in post chlorization hydrogen less than 0.5ppm;
C. then from the adsorption tower bottom that the SSZ-13 zeolite molecular sieve is housed, enter, after adsorbing and removing carbonic acid gas and denier moisture, from tower top out, after absorption, carbon dioxide content is less than 2ppm;
D. be forced into 2.2MP, enter and take off light rectifying tower, nitrogen, oxygen after being condensed to-18 ℃, hydrogen, carbon monoxide, the low-boiling point gas such as methane are discharged from tower top, form tail gas and reclaim, remove rear a nitrogen content less than 2ppm, oxygen content is less than 1ppm, and carbon monoxide content is less than 1ppm, and methane is less than 1ppm;
E. enter and take off heavy rectifying tower from taking off at the bottom of light rectifying tower out hydrogenchloride liquid, vaporization removes the high boiling component heavier than hydrogenchloride;
F. eject the high-purity hydrogen chloride purity of coming and reach more than 99.999% from taking off heavy rectifying tower, compressed bulking system bottling, high-purity hydrogen chloride after bottling, the metal ion total content is less than 0.3ppm, wherein metal ion removes a part by sorbent material, removes remainder by taking off heavy rectifying tower in addition.
The present invention adopts industrial synthesising hydrogen as raw material, major cause is: in the petrochemical complex by-product hydrogen chloride, organic impurity is many, particularly the C2 hydro carbons is difficult for and HCl separation, and the organic impurity of synthesising hydrogen is wanted much less relatively, compares easily purifying of petrochemical complex by-product hydrogen chloride.Whole nation by-product hydrogen chloride is a lot, and at present multiplex in synthetic hydrochloric acid, the price of hydrochloric acid is lower, and profit is not high, and electronic grade hydrogen chloride is expensive, can be enterprise and brings benefit.
Siccative used in the present invention and sorbent material are all through 200 ℃ of high-temperature chlorine gas disposals 2 hours, and after processing, the dust rate reduces, and intensity enhancing can meet dry and the absorption requirement.
, in order repeatedly to reuse siccative and sorbent material, use the constant-pressure and high-temperature reclaiming process to make it regeneration in the present invention, the siccative after regeneration and sorbent material can meet this processing requirement.
Realize serialization production for enhancing productivity, can arrange and organize dry adsorption units more, after one group of device adsorptive power descends, only need be switched to another group adsorption unit and get final product, needn't stop, one group under being switched simultaneously enters step for regeneration and regenerates rear standby.
In this technique, all pipeline equipments are all through de-oiling and slagging-off primary treatment, polishing, passivation and dehydration special processing and fill before precision process, the isolation of system and atmosphere in the assurance filling process, make bottled product each component content basically identical with online product content measured value.
Embodiment 2:
Preparation method of the present invention comprises the following steps:
A. after primary industry hydrogenchloride compresses after filtration, under the pressure of 0.3MP and normal temperature with 1.5 M
3The flow of/h enters from one-level drying tower 1 bottom of 13X type zeolite molecular sieve that numbering DH05 is housed, after the adsorbing and removing most of moisture from tower top out;
B. enter again the secondary drying tower bottom of 13X type zeolite molecular sieve that numbering DH06 is housed,, through deep dehydration, remove after micro-moisture from tower top out, remove moisture content in post chlorization hydrogen less than 0.5ppm;
C. then from the adsorption tower bottom that the SSZ-13 zeolite molecular sieve is housed, enter, after adsorbing and removing carbonic acid gas and denier moisture, from tower top out, after absorption, carbon dioxide content is less than 2ppm;
D. be forced into 2.0MP, enter and take off light rectifying tower, nitrogen, oxygen after being condensed to-20 ℃, hydrogen, carbon monoxide, the low-boiling point gas such as methane are discharged from tower top, form tail gas and reclaim, remove rear a nitrogen content less than 2ppm, oxygen content is less than 1ppm, and carbon monoxide content is less than 1ppm, and methane is less than 1ppm;
E. enter and take off heavy rectifying tower from taking off at the bottom of light rectifying tower out hydrogenchloride liquid, vaporization removes the high boiling component heavier than hydrogenchloride;
F. eject the high-purity hydrogen chloride purity of coming and reach more than 99.999% from taking off heavy rectifying tower, compressed bulking system bottling, the high-purity hydrogen chloride after bottling, the metal ion total content is less than 0.3ppm.
Although the present invention with preferred embodiment openly as above; but it is not to limit the present invention; any those skilled in the art without departing from the spirit and scope of the present invention; can utilize method and the technology contents of above-mentioned announcement to make possible change and modification to technical solution of the present invention; therefore; every content that does not break away from technical solution of the present invention;, to any simple modification made for any of the above embodiments, equivalent variations and modification, all belong to the protection of technical solution of the present invention according to technical spirit of the present invention.
Claims (10)
1. a method for preparing electronic grade high-purity hydrogenchloride take industrial synthesising hydrogen as raw material, is characterized in that, comprises the following steps:
A. after primary industry hydrogenchloride compresses after filtration, from the one-level drying tower bottom that siccative is housed, enter, after the adsorbing and removing most of moisture from tower top out;
B. enter again the secondary drying tower bottom that siccative is housed,, through deep dehydration, remove after micro-moisture from tower top out, remove moisture content in post chlorization hydrogen less than 0.5ppm;
C. then from the adsorption tower bottom that sorbent material is housed, enter, after adsorbing and removing carbonic acid gas and denier moisture, from tower top out, after absorption, carbon dioxide content is less than 2ppm;
D. pressurization, enter after condensation and take off light rectifying tower, nitrogen, oxygen, hydrogen, carbon monoxide, the low-boiling point gas such as methane are discharged from tower top, form tail gas and reclaim, remove rear a nitrogen content less than 2ppm, oxygen content is less than 1ppm, and carbon monoxide content is less than 1ppm, methane is less than 1ppm, and hydrogen content is less than 0.2ppm;
E. enter and take off heavy rectifying tower from taking off at the bottom of light rectifying tower out hydrogenchloride liquid, vaporization removes high boiling component and most of metal ion heavier than hydrogenchloride;
F. eject the high-purity hydrogen chloride purity of coming and reach more than 99.999% from taking off heavy rectifying tower, compressed bulking system bottling, the high-purity hydrogen chloride after bottling, the metal ion total content is less than 0.3ppm.
2. method according to claim 1, is characterized in that, also is provided with multistage physical dryness after step b.
3. method according to claim 1, is characterized in that, the siccative in step a and step b is zeolite molecular sieve.
4. method according to claim 2, is characterized in that, the siccative in step a and step b is the 13X zeolite molecular sieve.
5. method according to claim 1, is characterized in that, the sorbent material in step c is zeolite molecular sieve.
6. method according to claim 4, is characterized in that, the sorbent material in step c is the SSZ-13 zeolite molecular sieve.
7. according to claim 1-6 described methods of any one, is characterized in that, the siccative in step a and step b, the sorbent material in step c are all through 200 ℃ of high-temperature chlorine gas disposals two hours.
8. method according to claim 7, is characterized in that, after step a Raw industry synthesising hydrogen compresses after filtration, under the pressure and normal temperature of 0.3-0.6MP, with 1-5M
3The flow of/h enters the one-level drying tower.
9. method according to claim 7, is characterized in that, in steps d hydrogenchloride from adsorption tower out after, be compressed to 1.5-2.5MP, be cooled to-15 ℃--25 ℃.
10. method according to claim 9, is characterized in that, in steps d hydrogenchloride from adsorption tower out after, be compressed to 2.0MP, be cooled to-20 ℃.
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105399053A (en) * | 2015-12-07 | 2016-03-16 | 南通山剑石墨设备有限公司 | Hydrogen chloride drying system |
| CN105502294A (en) * | 2015-12-28 | 2016-04-20 | 青岛科技大学 | Electronic-grade high-purity hydrogen chloride high-pressure preparation method |
| CN106276796A (en) * | 2016-07-19 | 2017-01-04 | 浙江博瑞电子科技有限公司 | A kind of method preparing high-purity hydrogen chloride |
| CN107746040A (en) * | 2017-10-17 | 2018-03-02 | 山东新龙科技股份有限公司 | A kind of Processes and apparatus that hydrogen chloride is refined using the by-product gas for producing trichloro ethylene |
| CN107840307A (en) * | 2017-11-30 | 2018-03-27 | 南通星球石墨设备有限公司 | A kind of HCl gas synthesis driving system |
| CN108557766A (en) * | 2018-02-11 | 2018-09-21 | 浙江博瑞电子科技有限公司 | A kind of process for purification of hydrogen chloride |
| CN109368593A (en) * | 2018-11-26 | 2019-02-22 | 浙江博瑞电子科技有限公司 | A method of preparing the electronic grade hydrogen chloride gas of ppbv grades of moisture impurities |
| CN110508105A (en) * | 2019-08-28 | 2019-11-29 | 山东康宝生化科技有限公司 | A kind of apparatus and method separating carbon dioxide and hydrogen chloride in Sucralose tail gas |
| CN114634163A (en) * | 2022-05-18 | 2022-06-17 | 北京化工大学 | Production device and method for manufacturing electronic-grade hydrogen chloride |
| KR20230058221A (en) | 2021-10-22 | 2023-05-03 | 효성화학 주식회사 | Methode for preparing high-purity hydrogen chloride |
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| CN1644487A (en) * | 2004-12-21 | 2005-07-27 | 上海氯碱化工股份有限公司 | Apparatus and method for preparing high-purity hydrochloric acid by low-temperature evaporation |
| CN101200286A (en) * | 2007-12-05 | 2008-06-18 | 南京大学 | Method for refining byproduct hydrogen chloride during production process of organochlorine products |
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Patent Citations (2)
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| CN1644487A (en) * | 2004-12-21 | 2005-07-27 | 上海氯碱化工股份有限公司 | Apparatus and method for preparing high-purity hydrochloric acid by low-temperature evaporation |
| CN101200286A (en) * | 2007-12-05 | 2008-06-18 | 南京大学 | Method for refining byproduct hydrogen chloride during production process of organochlorine products |
Cited By (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105399053B (en) * | 2015-12-07 | 2018-01-30 | 南通山剑石墨设备有限公司 | Hydrogen chloride drying system |
| CN105399053A (en) * | 2015-12-07 | 2016-03-16 | 南通山剑石墨设备有限公司 | Hydrogen chloride drying system |
| CN105502294B (en) * | 2015-12-28 | 2018-11-20 | 青岛科技大学 | A kind of electronic grade high-purity hydrogen chloride high pressure method for preparing |
| CN105502294A (en) * | 2015-12-28 | 2016-04-20 | 青岛科技大学 | Electronic-grade high-purity hydrogen chloride high-pressure preparation method |
| CN106276796A (en) * | 2016-07-19 | 2017-01-04 | 浙江博瑞电子科技有限公司 | A kind of method preparing high-purity hydrogen chloride |
| CN106276796B (en) * | 2016-07-19 | 2019-06-14 | 浙江博瑞电子科技有限公司 | A method of preparing high-purity hydrogen chloride |
| CN107746040B (en) * | 2017-10-17 | 2021-04-13 | 山东新龙科技股份有限公司 | Process and equipment for refining hydrogen chloride by using byproduct gas from production of trichloroethylene |
| CN107746040A (en) * | 2017-10-17 | 2018-03-02 | 山东新龙科技股份有限公司 | A kind of Processes and apparatus that hydrogen chloride is refined using the by-product gas for producing trichloro ethylene |
| CN107840307A (en) * | 2017-11-30 | 2018-03-27 | 南通星球石墨设备有限公司 | A kind of HCl gas synthesis driving system |
| CN108557766A (en) * | 2018-02-11 | 2018-09-21 | 浙江博瑞电子科技有限公司 | A kind of process for purification of hydrogen chloride |
| CN108557766B (en) * | 2018-02-11 | 2019-12-27 | 浙江博瑞电子科技有限公司 | Refining method of hydrogen chloride |
| CN109368593A (en) * | 2018-11-26 | 2019-02-22 | 浙江博瑞电子科技有限公司 | A method of preparing the electronic grade hydrogen chloride gas of ppbv grades of moisture impurities |
| CN110508105A (en) * | 2019-08-28 | 2019-11-29 | 山东康宝生化科技有限公司 | A kind of apparatus and method separating carbon dioxide and hydrogen chloride in Sucralose tail gas |
| CN110508105B (en) * | 2019-08-28 | 2021-08-10 | 山东康宝生化科技有限公司 | Device and method for separating carbon dioxide and hydrogen chloride from sucralose tail gas |
| KR20230058221A (en) | 2021-10-22 | 2023-05-03 | 효성화학 주식회사 | Methode for preparing high-purity hydrogen chloride |
| CN114634163A (en) * | 2022-05-18 | 2022-06-17 | 北京化工大学 | Production device and method for manufacturing electronic-grade hydrogen chloride |
| CN114634163B (en) * | 2022-05-18 | 2022-08-05 | 北京化工大学 | Production device and method for manufacturing electronic grade hydrogen chloride |
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