CN101570318B - Method for producing electronic-stage hydrofluoric acid - Google Patents
Method for producing electronic-stage hydrofluoric acid Download PDFInfo
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- CN101570318B CN101570318B CN2008100496618A CN200810049661A CN101570318B CN 101570318 B CN101570318 B CN 101570318B CN 2008100496618 A CN2008100496618 A CN 2008100496618A CN 200810049661 A CN200810049661 A CN 200810049661A CN 101570318 B CN101570318 B CN 101570318B
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Abstract
The invention relates to a method for producing electronic-stage hydrofluoric acid. The method comprises the following steps: (1), preheating and roughly distilling a measured anhydrous hydrofluoric acid raw material to remove low boiling point matter; (2), using ultra-pure water to absorb hydrofluoric acid roughly distillated and exhausted from a condenser outlet to be 48 to 49 percent of hydroushydrofluoric acid solution; (3), distilling an absorbed hydrofluoric acid semi-finished product by a fluoroplastic resin sub-boiling distiller, gasifying fluorine hydride liquid to generate ultra-pur e electronic-stage hydrofluoric acid gas, condensing to be 48 to 49 percent of anhydrous hydrofluoric acid solution and remaining high boiling point matter and heavy metals at the bottom of the sub-boiling distiller; and (4), secondarily filtering the hydrofluoric acid semi-finished product output from the fluoroplastic resin sub-boiling distiller, and finally, automatically filling to prepare 48 percent of ultra-pure hydrofluoric acid finished product. The method fully utilizes the different of boiling points between the anhydrous hydrofluoric acid and various impurities in the anhydrous hydrofluoric acid to remove the impurities at different temperatures, particularly remove silicon so that the impurity content of the obtained ultra-pure hydrofluoric acid is decreased to the minimum.
Description
Technical field
The present invention relates to a kind of method of producing electronic-stage hydrofluoric acid, relating in particular to the anhydrous hydrofluoric acid is the method for main material production electronic-stage hydrofluoric acid.
Background technology
Electronic-stage hydrofluoric acid (Hydrofuloric acid, electronic grade) claim high-pure hydrofluoric acid again.Molecular formula HF, molecular weight 20.006.One of key basic chemical industry material that electronic-stage 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.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, the pure hydrofluoric acid of general electronics far can not satisfy the harsh requirement in market, and the preparation high-pure hydrofluoric acid has just become the deep processing of hydrogen fluoride production enterprise and improved one of direction of added value of product.That electronic-stage hydrofluoric acid has is wide in variety, consumption is big, technical requirements is high, storage life is short and characteristics such as severe corrosive.
After generally adopting industrial anhydrous hydrofluoric acid to add the potassium permanganate reaction at present, directly the rectifying purifying prepares electronic-stage hydrofluoric acid, be high-purity hydrogen fluoride, the hydrofluoric acid purity that this kind method makes is lower, particularly arsenous fluoride separates not exclusively in the hydrofluoric acid, so the ultra-pure 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.In addition, because hydrogen fluoride gas can not be absorbed fully, its exhaust emissions pollutes surrounding environment easily in the preparation process of present electronic-stage hydrofluoric acid.
Summary of the invention
The object of the present invention is to provide a kind of method of producing electronic-stage hydrofluoric acid, its technical process is simple, less investment, the product purity height of production.
To achieve these goals, technical scheme of the present invention has adopted a kind of method of producing electronic-stage hydrofluoric acid, specifically may further comprise the steps:
(1) slightly heat up in a steamer: the anhydrous hydrofluoric acid raw material through measuring slightly heats up in a steamer after preheating, removes low-boiling point material;
(2) absorb: will be after slightly heating up in a steamer, the hydrofluoric acid of discharging from condensator outlet absorbs with ultrapure water, and tower still temperature is 40～60 ℃, and the body of the tower temperature is 40～50 ℃, the condensator outlet temperature is 20～40 ℃, condensed liquid be 48～49% the water hydrofluoric acid solution arranged;
(3) fluorine is moulded the rectifying of fat sub-boiling distillation device: the hydrofluoric acid work in-process of good absorption are moulded the distillation of fat sub-boiling distillation device through fluorine, temperature is 60～80 ℃, the gasification of hydrogen fluoride liquid generates hyperpure electronic-stage hydrofluoric acid gas, after the condensation be 48～49% the water hydrofluoric acid solution arranged, high boiling substance and heavy metal are stayed sub-boiling distillation device bottom;
(4) membrane filtration: from fluorine mould hydrofluoric acid work in-process that fat sub-boiling distillation device comes out through cascade filtration after auto-filling is made 48% ultra-pure hydrofluoric acid finished product.
The concrete steps of described step (1) are: the anhydrous hydrofluoric acid raw material after will measuring flows out in the storage bottle, after the preheater preheating, enter and slightly heat 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, add oxygenant, its add-on accounts for 0.5～2.5% of anhydrous hydrofluoric acid raw material weight, makes a large amount of sulfurous gas and the arsenous fluoride generation that contain in the industrial anhydrous hydrofluoric acid be difficult to the evaporable compound; Add weight concentration then and be 30% hydrogen peroxide, the add-on of hydrogen peroxide accounts for 1～3% of anhydrous hydrogen fluoride for industrial use, is 30～50 ℃ at the topping still temperature in the kettle, and the overhead condenser temperature out is 10～19 ℃.
Described oxygenant is a kind of or its combination among potassium permanganate solution, (NH4) 2S2O8 or the KHF2.
The filtration of described step (4) is specially: 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 anhydrous hydrofluoric acid that method of the present invention has made full use of anhydrous hydrofluoric acid, under differing temps, removes different impurity, and especially silicon makes the ultra-pure hydrofluoric acid foreign matter content that obtains drop to minimum.The present invention has utilized the strong oxidizing property of oxidant potassium permanganate, (NH4) 2S2O8, KHF2 and hydrogen peroxide, a large amount of sulfurous gas that contain in the anhydrous hydrogen fluoride for industrial use and arsenous fluoride oxidation generation are difficult to evaporable sulphur trioxide and K2AsF7, the 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 ultra-pure hydrofluoric acid, has increased economic benefit and environmental benefit again.
The present invention utilizes fluorine to mould the heat radiation principle of fat sub-boiling distillation device, keeps liquidus temperature to be lower than the boiling temperature evaporative condenser and produces the principle of high purity reagent, has reduced equipment and investment, has increased output simultaneously, and production cost further reduces.
The inventive method following advantage of having compared with present production technique:
(1) the boiling point difference by each material, potassium permanganate or (NH4) strong oxidizing property of 2S2O8 and KHF2 and hydrogen peroxide, thoroughly solved the difficult problem that silicon and trivalent arsenic etc. are difficult for removing, carry out fluorine simultaneously and mould the distillation of fat sub-boiling distillation device, make product purity further improve, the ultra-pure 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 the present invention produced, content are generally hydrofluoric acid, silicofluoric acid etc., and concentration is about 50～60%, can be used for the sodium aluminum fluoride production line.Alleviate environmental protection pressure, reduced consumption, 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 ultra-pure hydrofluoric acid that granule foreign content drops to, and reaches semi-conductor SEMI-C12 standard.Granule number is 0.2 μ m≤50.
(4) the present invention utilizes fluorine to mould fat sub-boiling distillation device to carry out secondary rectifying, reduced equipment and investment, and the simple equipments floor space is little, has increased output simultaneously, and production cost further reduces.
Embodiment
Embodiment 1
Method of the present invention specifically may further comprise the steps: slightly heat up in a steamer (1): the anhydrous hydrofluoric acid raw material of 350kg is flowed out in the storage bottle, 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, add the 5.25kg potassium permanganate solution, make a large amount of sulfurous gas and the arsenous fluoride generation that contain in the industrial anhydrous hydrofluoric acid be difficult to the evaporable compound; Add the 7kg weight percentage then and be 30% hydrogen peroxide, 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; (2) absorb: 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 or takes out as commodity; Treat that gas that the water condenser top exit is derived reaches 1.5% o'clock of anhydrous hydrofluoric acid weight, 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 45 ℃, and the condensator outlet temperature is 30 ℃, condensed liquid-absorbent be 48%～49% the water hydrofluoric acid solution arranged; (3) fluorine is moulded the rectifying of fat sub-boiling distillation device: the hydrofluoric acid solution with 48%～49% carries out fluorine to be moulded fat sub-boiling distillation device and carries out secondary rectifying, and temperature is 70 ℃; (4) membrane filtration: mould the hydrofluoric acid work in-process that fat sub-boiling distillation device distills from fluorine, 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 ultra-pure hydrofluoric acid finished product of 640kg 48% (wt).Analytical results: granule number is 0.2 μ m≤50, purity: negatively charged ion≤25ppb, positively charged ion≤0.03ppb.
Embodiment 2
Method of the present invention specifically may further comprise the steps: slightly heat up in a steamer (1): the anhydrous hydrofluoric acid raw material of 250kg is flowed out in the storage bottle, 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, add 2.5kg (NH4) 2S2O8, make a large amount of sulfurous gas and the arsenous fluoride generation that contain in the industrial anhydrous hydrofluoric acid be difficult to the evaporable compound; Add the 5kg weight percentage then and be 30% hydrogen peroxide, 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; (2) absorb: 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 or takes out as commodity; Treat that gas that the water condenser top exit is derived reaches 2% o'clock of anhydrous hydrofluoric acid weight, 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 55 ℃, and the body of the tower temperature is 40 ℃, and the condensator outlet temperature is 40 ℃, condensed liquid-absorbent be 48%～49% the water hydrofluoric acid solution arranged; (3) fluorine is moulded the rectifying of fat sub-boiling distillation device: the hydrofluoric acid solution with 48%～49% carries out fluorine to be moulded fat sub-boiling distillation device and carries out secondary rectifying, and temperature is 80 ℃; (4) membrane filtration: mould the hydrofluoric acid work in-process that fat sub-boiling distillation device distills from fluorine, 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 ultra-pure hydrofluoric acid finished product of 400kg 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 (1)
1. method of producing electronic-stage hydrofluoric acid is characterized in that: specifically may further comprise the steps:
(1) slightly heat up in a steamer: the anhydrous hydrofluoric acid raw material through measuring slightly heats up in a steamer after preheating, removes low-boiling point material;
(2) absorb: will be after slightly heating up in a steamer, the hydrofluoric acid of discharging from condensator outlet absorbs with ultrapure water, and tower still temperature is 40～60 ℃, and the body of the tower temperature is 40～50 ℃, the condensator outlet temperature is 20～40 ℃, condensed liquid be 48～49% the water hydrofluoric acid solution arranged;
(3) fluorine is moulded the rectifying of fat sub-boiling distillation device: the hydrofluoric acid work in-process of good absorption are moulded the distillation of fat sub-boiling distillation device through fluorine, temperature is 60～80 ℃, the gasification of hydrogen fluoride liquid generates hyperpure electronic-stage hydrofluoric acid gas, after the condensation be 48～49% the water hydrofluoric acid solution arranged, high boiling substance and heavy metal are stayed fluorine and are moulded fat sub-boiling distillation device bottom;
(4) membrane filtration: from fluorine mould hydrofluoric acid work in-process that fat sub-boiling distillation device comes out through cascade filtration after auto-filling is made 48% ultra-pure hydrofluoric acid finished product;
Wherein, the concrete steps of described step (1) are: the anhydrous hydrofluoric acid raw material after will measuring flows out in the storage bottle, after the preheater preheating, enter and slightly heat 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, add oxygenant, its add-on accounts for 0.5～2.5% of anhydrous hydrofluoric acid raw material weight, makes 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; Add weight concentration then and be 30% hydrogen peroxide, the add-on of hydrogen peroxide accounts for 1～3% of anhydrous hydrogen fluoride for industrial use, is 30-50 ℃ at the topping still temperature in the kettle, and the overhead condenser temperature out is 10-19 ℃; Described oxygenant is potassium permanganate solution, (NH
4)
2S
2O
8Or KHF
2In a kind of or its combination;
The filtration of described step (4) is specially: 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.
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| CN2008100496618A CN101570318B (en) | 2008-04-28 | 2008-04-28 | Method for producing electronic-stage hydrofluoric acid |
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| CN2008100496618A CN101570318B (en) | 2008-04-28 | 2008-04-28 | Method for producing electronic-stage hydrofluoric acid |
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| CN101570318B true CN101570318B (en) | 2011-12-14 |
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| CN102320573B (en) * | 2011-09-19 | 2013-04-03 | 瓮福（集团）有限责任公司 | Method for preparing electronic grade hydrofluoric acid |
| JP2013123673A (en) * | 2011-12-14 | 2013-06-24 | Sasakura Engineering Co Ltd | Method for treating hydrofluoric acid wastewater |
| CN102774858A (en) * | 2012-08-21 | 2012-11-14 | 天津市风船化学试剂科技有限公司 | Method for preparing ultra-purity ammonium-fluoride aggressive agents |
| CN103991847B (en) * | 2013-02-18 | 2015-12-23 | 福建省邵武市永晶化工有限公司 | Electronic-stage hydrofluoric acid preparation method |
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| CN105217575B (en) * | 2015-09-22 | 2017-08-25 | 中国船舶重工集团公司第七一八研究所 | A kind of method that reactive distillation removes moisture in hydrogen fluoride |
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| CN109592656A (en) * | 2019-01-31 | 2019-04-09 | 内蒙古通威高纯晶硅有限公司 | A kind of preparation method of impurity analysis acid |
| 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 |
| CN111994874B (en) * | 2020-09-03 | 2022-07-19 | 福建天甫电子材料有限公司 | Preparation method of electronic-grade hydrofluoric acid |
| CN112028022A (en) * | 2020-09-18 | 2020-12-04 | 宣城亨泰电子化学材料有限公司 | Pretreatment method for preparing electronic-grade high-purity 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 |
| CN113401874B (en) * | 2021-07-14 | 2022-04-05 | 浙江凯圣氟化学有限公司 | Method for removing arsenic in electronic-grade hydrofluoric acid |
| CN115433580B (en) * | 2022-10-27 | 2023-08-18 | 湖北九宁化学科技有限公司 | Production method of etching solution in photoelectric industry |
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Inventor after: Hou Hongjun Inventor after: Fang Zhichao Inventor after: Liu Haixia Inventor after: Yang Huachun Inventor after: Yu Hehua Inventor after: Xue Xujin Inventor after: Chen Hongwei Inventor after: Han Jianjun Inventor after: Liu Haiqing Inventor after: Shang Zhongsheng Inventor before: Huangfu Genli Inventor before: Hou Hongjun Inventor before: Liu Haixia Inventor before: Zhang Liang Inventor before: Liu Xiaoxia |
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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. |