CN103896215A - Fluorite-sulfuric acid method for preparing hydrogen fluoride - Google Patents
Fluorite-sulfuric acid method for preparing hydrogen fluoride Download PDFInfo
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- CN103896215A CN103896215A CN201210588971.3A CN201210588971A CN103896215A CN 103896215 A CN103896215 A CN 103896215A CN 201210588971 A CN201210588971 A CN 201210588971A CN 103896215 A CN103896215 A CN 103896215A
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- fluorite
- hydrogen fluoride
- sulfuric acid
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Abstract
The invention discloses a fluorite-sulfuric acid method for preparing hydrogen fluoride. The method comprises the following steps: drying, smashing and sieving acid making fluorite until the particle size is less than 150mu m, wherein the acid making fluorite contains more than 97% of CaF2, less than 1% of SiO2, and less than 1% of CaCO3; then proportioning the particulate fluorite and 98% concentrated sulfuric acid, and then feeding the mixture into a rotary furnace for reacting, wherein the gaseous phase temperature in the furnace is controlled at 280+/-10DEG C; discharging the calcium sulfate generated in the reaction from the tail of the furnace; rectifying and purifying so as to prepare anhydrous hydrogen fluoride with the purity of 99.8% or higher. The fluorite-sulfuric acid method is the best method for preparing hydrogen fluoride.
Description
Technical field
The invention belongs to industrial chemicals preparing technical field, the present invention adopts fluorite-sulfuric acid process to prepare hydrogen fluoride.The method reduces equipment corrosion, improves the thermo-efficiency of reaction and the utilization ratio of raw material.
Background technology
1. by anhydrous KHF
2decompose and prepare hydrogen fluoride
The a small amount of anhydrous hydrogen fluoride of use for laboratory can be used potassium hydride difluoride (KHF
2) make 500 ℃ of high temperature thermolysiss, reaction formula is as follows:
KHF
2 
KF + HF
By KHF
2in the platinum system of being placed on or matrass made of copper or flask, with lamp heating, condensed fluid collection is in the copper susceptor with ice-cooled, and susceptor is equipped with calcium chloride tube.10～20 initial ml phlegmas discard, remaining phlegma in water-bath in 35～39 ℃ of redistillation once.
Industrial KHF
2what have is impure, can be dissolved in hot water, adds a little PbCO
3to remove Cl
-.Deng PbClF, K
2siF
6after precipitation, settled solution evaporative crystallization in ware made of copper.
2. by NH
4f produces hydrogen fluoride
First that NH4F is dry at 100～110 ℃, then salt is packed in copper matrass or copper flask and with anhydrous HCl processing, in the susceptor that is cooled to-50 ℃, collect phlegma.The HF obtaining is containing 0.1%～0.12% water and a small amount of HCl impurity.Preparation after distillation is without Cl-.
3. Calcium Fluoride (Fluorspan) and sulfuric acid reaction method
If not high to hydrogen fluoride purity requirement, also can make with Calcium Fluoride (Fluorspan) and sulfuric acid reaction.
Summary of the invention
Problem to be solved by this invention is, overcomes the deficiencies in the prior art, provides a kind of fluorite-sulfuric acid process that adopts to prepare hydrogen fluoride, and method, is characterized in that containing CaF
2> 97%, SiO
2< 1%, CaCO
3the relieving haperacidity level fluorite drying of < 1%, crush and screen to granularity < 150 μ m and send in rotary kiln and react by the proportioning of 1:1.2～1.3 with 98% vitriol oil; Rotary kiln front-end temperature is 160～180 ℃, and back segment is 220～280 ℃, and in stove, gas phase temperature is controlled at (280 ± 10) ℃; The calcium sulfate that reaction generates is discharged by stove tail; After reactant gases product mixtures is discharged by burner, after enter topping still, tower reactor temperature is controlled at 100～110 ℃, tower top temperature is controlled at 35～40 ℃, to remove most of sulfuric acid, water vapour and calcium sulfate, fluorite dust; Then hydrogen fluoride gas enters degassing tower, tower reactor temperature is controlled at 20～23 ℃, tower top temperature is-7～-9 ℃, the lower-boiling impurity such as sulfurous gas and silicon tetrafluoride is discharged by tower top, and thick hydrogen fluoride is condensed into liquid state, by discharging and enter rectifying tower at the bottom of tower, tower reactor temperature is controlled at 30～40 ℃, tower top temperature is controlled at (19.6 ± 0.5) ℃, further to remove remaining a small amount of sulfuric acid and water, after rectifying purifies, can make 99.8% or more highly purified anhydrous hydrogen fluoride.
Original technology is that the hydrofluoric traditional method of industrial preparation is that fluorite is mixed with the vitriol oil, and heat makes, and main reaction formula is as follows:
CaF
2 + H
2SO
4 
2HF↑+ CaSO
4
In addition, owing to containing the impurity such as silicon-dioxide, calcium carbonate, aluminum oxide and iron ore in fluorite, thereby be also attended by following side reaction generation:
SiO
2 + 4HF → SiF
4 + 2H
2O
SiF
4 + 2HF →H
2SiF
6
CaCO
3+H
2SO
4 →CaSO
4+H
2O+CO
2↑
Al
2O
3+3H
2SO
4→Al
2(SO
4)
3+3H
2O
Fe
2O
3+3H
2SO
4→Fe
2(SO
4)
3+3H
2O
Therefore, expect pure anhydrous hydrogen fluoride, the impurity that side reaction must be produced separates and removes with hydrogen fluoride.
Containing CaF
2> 97%, SiO
2< 1%, CaCO
3the relieving haperacidity level fluorite drying of < 1%, crush and screen to after granularity < 150 μ m with 98% vitriol oil by 1:(1.2～1.3) proportioning send in rotary kiln and react.Rotary kiln front-end temperature is 160～180 ℃, and back segment is 220～280 ℃, and in stove, gas phase temperature is controlled at (280 ± 10) ℃.The calcium sulfate that reaction generates is discharged by stove tail.The gas that reaction generates contains a small amount of water vapour, sulfuric acid mist, sulfurous gas, silicon tetrafluoride, sublimed sulphur, carbon dioxide and unreacted fluorite, calcium sulfate dust etc.After reactant gases product mixtures is discharged by burner, after enter topping still, tower reactor temperature is controlled at 100～110 ℃, tower top temperature is controlled at 35～40 ℃, to remove most of sulfuric acid, water vapour and calcium sulfate, fluorite dust etc.Then hydrogen fluoride gas enters degassing tower, tower reactor temperature is controlled at 20～23 ℃, tower top temperature is-7～-9 ℃, the lower-boiling impurity such as sulfurous gas and silicon tetrafluoride is discharged by tower top, and thick hydrogen fluoride is condensed into liquid state, by discharging and enter rectifying tower at the bottom of tower, tower reactor temperature is controlled at 30～40 ℃, tower top temperature is controlled at (19.6 ± 0.5) ℃, further to remove remaining a small amount of sulfuric acid and water, after rectifying purifies, can make 99.8% or more highly purified anhydrous hydrogen fluoride.
If need the hydrofluoric acid of certain concentration of preparation, used water absorbs a certain amount of hydrogen fluoride, makes it reach normality.
In reaction process, in the waste residue anhydrous calciumsulphate of by-product, contain free acid, in available lime and rear further disposal, what have directly delivers to cement mill making cement retardant, also can be used for manufacturing material of construction or other purposes.The spent acid of discharging can add after the vitriol oil or oleum are made into 98% sulfuric acid and recycles as raw material, or as other purposes.The waste gas that degassing tower is discharged enters water wash column, and the silicon tetrafluoride absorbing wherein with water becomes 20%～30% silicofluoric acid, and this silicofluoric acid is further used as the raw materials for production of other fluorochemicals.
The quality product of fluorite-Production By Sulfuric Acid Process and yield are except being subject to fluorite granularity, sulfuric acid concentration, sulfuric acid and fluorite liquid-solid ratio, reaction temperatures affect, and in fluorite, the impact of foreign matter content is also very large.Relieving haperacidity level fluorite chemical constitutions all in production generally should reach following index:
CaF
2＞93%～98%
SiO
2＜0.8%～1.5%
CaCO
3＜1%～1.5%
As too high in dioxide-containing silica, meeting and HF react the yield that generates silicon tetrafluoride and reduce HF, thereby increase sulfuric acid consumption.As too highly in calcium carbonate content also can increase sulfuric acid consumption, and in reactor, form carbon dioxide foaming, reduce the concentration of HF.
(2) anhydrous hydrogen fluoride is produced major equipment
The major equipment of anhydrous hydrogen fluoride production technique configuration comprises nitration mixture groove, rotary kiln, roasting kiln, degassing tower, topping still, rectifying tower, washing tower, absorption tower, pan tank, filling apparatus, recirculation blower and other non-standard equipments etc.Wherein need important consideration rot-resistant equipment to have rotary kiln, degassing tower, topping still and washing tower and absorption tower.
(3) anhydrous hydrogen fluoride production cost forms
Anhydrous hydrogen fluoride production cost is mainly determined by three factors:
1. the raw-material cost such as fluorite, sulfuric acid, silicofluoric acid, an alkali metal salt;
2. energy consumption;
3. depreciation of fixed assets and overhaul of the equipments expense;
4. working cost.
Fluorite-sulfuric acid process unit ton hydrogen fluoride production main raw material(s) and energy consumption are specified as follows:
Fluorite (97%CaF
2): 2165 kg
Sulfuric acid (98%H
2sO
4): 2600 kg
The improved direction of this method is to reduce equipment corrosion, improves the thermo-efficiency of reaction and the utilization ratio of raw material.Done in recent years following a few thing for this reason:
1. adopt special premixer, can greatly reduce rotary kiln corrosion, and throughput is improved more than 30%;
2. recycle spent acid;
3. use oleum;
4. use sulfate spray;
5. adopt sulphur trioxide and water vapour to replace sulfuric acid;
6. dilute sulphuric acid or pulpous state gypsum, diluted hydrofluoric acid are added to and in Fluorspar Powder, carry out granulation;
7. use preheating sulfuric acid, fluorite, oleum;
8. adopt sulfuric acid vapor and water vapour fluidized bed device;
9. adopt improved second reactor;
10. adopt three reactor.
Embodiment
Below in conjunction with embodiment, the present invention is further described, and following embodiment is illustrative, is not determinate, can not limit protection scope of the present invention with following embodiment.Raw material wherein can have been bought in market.
Embodiment 1
A kind of fluorite-sulfuric acid process that adopts is prepared hydrogen fluoride, and method is characterized in that containing CaF
2> 97%, SiO
2< 1%, CaCO
3the relieving haperacidity level fluorite drying of < 1%, crush and screen to granularity < 150 μ m and send in rotary kiln and react by the proportioning of 1:1.2 with 98% vitriol oil; Rotary kiln front-end temperature is 160 ℃, and back segment is 220 ℃, and in stove, gas phase temperature is controlled at (280 ± 10) ℃; The calcium sulfate that reaction generates is discharged by stove tail; After reactant gases product mixtures is discharged by burner, after enter topping still, tower reactor temperature is controlled at 100 ℃, tower top temperature is controlled at 35 ℃, to remove most of sulfuric acid, water vapour and calcium sulfate, fluorite dust; Then hydrogen fluoride gas enters degassing tower, tower reactor temperature is controlled at 20 ℃, tower top temperature is-7 ℃, the lower-boiling impurity such as sulfurous gas and silicon tetrafluoride is discharged by tower top, and thick hydrogen fluoride is condensed into liquid state, by discharging and enter rectifying tower at the bottom of tower, tower reactor temperature is controlled at 30 ℃, tower top temperature is controlled at (19.6 ± 0.5) ℃, further to remove remaining a small amount of sulfuric acid and water, after rectifying purifies, can make 99.8% or more highly purified anhydrous hydrogen fluoride.
Embodiment 2
A kind of fluorite-sulfuric acid process that adopts is prepared hydrogen fluoride, and method is characterized in that containing CaF
2> 97%, SiO
2< 1%, CaCO
3the relieving haperacidity level fluorite drying of < 1%, crush and screen to granularity < 150 μ m and send in rotary kiln and react by the proportioning of 1:1.3 with 98% vitriol oil; Rotary kiln front-end temperature is 180 ℃, and back segment is 280 ℃, and in stove, gas phase temperature is controlled at (280 ± 10) ℃; The calcium sulfate that reaction generates is discharged by stove tail; After reactant gases product mixtures is discharged by burner, after enter topping still, tower reactor temperature is controlled at 110 ℃, tower top temperature is controlled at 35～40 ℃, to remove most of sulfuric acid, water vapour and calcium sulfate, fluorite dust; Then hydrogen fluoride gas enters degassing tower, tower reactor temperature is controlled at 20～23 ℃, tower top temperature is-9 ℃, the lower-boiling impurity such as sulfurous gas and silicon tetrafluoride is discharged by tower top, and thick hydrogen fluoride is condensed into liquid state, by discharging and enter rectifying tower at the bottom of tower, tower reactor temperature is controlled at 40 ℃, tower top temperature is controlled at (19.6 ± 0.5) ℃, further to remove remaining a small amount of sulfuric acid and water, after rectifying purifies, can make 99.8% or more highly purified anhydrous hydrogen fluoride.
Embodiment 3
A kind of fluorite-sulfuric acid process that adopts is prepared hydrogen fluoride, and method is characterized in that containing CaF
2> 97%, SiO
2< 1%, CaCO
3the relieving haperacidity level fluorite drying of < 1%, crush and screen to granularity < 150 μ m and send in rotary kiln and react by the proportioning of 1:1.25 with 98% vitriol oil; Rotary kiln front-end temperature is 170 ℃, and back segment is 260 ℃, and in stove, gas phase temperature is controlled at (280 ± 10) ℃; The calcium sulfate that reaction generates is discharged by stove tail; After reactant gases product mixtures is discharged by burner, after enter topping still, tower reactor temperature is controlled at 110 ℃, tower top temperature is controlled at 35～40 ℃, to remove most of sulfuric acid, water vapour and calcium sulfate, fluorite dust; Then hydrogen fluoride gas enters degassing tower, tower reactor temperature is controlled at 23 ℃, tower top temperature is-9 ℃, the lower-boiling impurity such as sulfurous gas and silicon tetrafluoride is discharged by tower top, and thick hydrogen fluoride is condensed into liquid state, by discharging and enter rectifying tower at the bottom of tower, tower reactor temperature is controlled at 40 ℃, tower top temperature is controlled at (19.6 ± 0.5) ℃, further to remove remaining a small amount of sulfuric acid and water, after rectifying purifies, can make 99.8% or more highly purified anhydrous hydrogen fluoride.
Claims (1)
1. adopt fluorite-sulfuric acid process to prepare a hydrogen fluoride, method, is characterized in that containing CaF
2> 97%, SiO
2< 1%, CaCO
3the relieving haperacidity level fluorite drying of < 1%, crush and screen to granularity < 150 μ m and send in rotary kiln and react by the proportioning of 1:1.2～1.3 with 98% vitriol oil; Rotary kiln front-end temperature is 160～180 ℃, and back segment is 220～280 ℃, and in stove, gas phase temperature is controlled at (280 ± 10) ℃; The calcium sulfate that reaction generates is discharged by stove tail; After reactant gases product mixtures is discharged by burner, after enter topping still, tower reactor temperature is controlled at 100～110 ℃, tower top temperature is controlled at 35～40 ℃, to remove most of sulfuric acid, water vapour and calcium sulfate, fluorite dust; Then hydrogen fluoride gas enters degassing tower, tower reactor temperature is controlled at 20～23 ℃, tower top temperature is-7～-9 ℃, the lower-boiling impurity such as sulfurous gas and silicon tetrafluoride is discharged by tower top, and thick hydrogen fluoride is condensed into liquid state, by discharging and enter rectifying tower at the bottom of tower, tower reactor temperature is controlled at 30～40 ℃, tower top temperature is controlled at (19.6 ± 0.5) ℃, further to remove remaining a small amount of sulfuric acid and water, after rectifying purifies, can make 99.8% or more highly purified anhydrous hydrogen fluoride.
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|---|---|---|---|
| CN201210588971.3A CN103896215A (en) | 2012-12-31 | 2012-12-31 | Fluorite-sulfuric acid method for preparing hydrogen fluoride |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210588971.3A CN103896215A (en) | 2012-12-31 | 2012-12-31 | Fluorite-sulfuric acid method for preparing hydrogen fluoride |
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ID=50987849
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104071817A (en) * | 2014-07-15 | 2014-10-01 | 辽宁石化职业技术学院 | Method for coproducing aluminium sulfate, white carbon black and ammonium fluoride |
| CN106276801A (en) * | 2016-08-25 | 2017-01-04 | 衢州南高峰化工有限公司 | A kind of production equipment and process of anhydrous hydrogen fluoride |
| CN108147439A (en) * | 2018-02-12 | 2018-06-12 | 沈阳鑫博工业技术股份有限公司 | A kind of device and method that magnesium fluoride is prepared using magnesite powder and fluorite |
| CN108298500A (en) * | 2017-01-12 | 2018-07-20 | 洛阳丰瑞氟业有限公司 | A kind of modification scheme improving anhydrous hydrogen fluoride yield and quality production technology |
| CN108580051A (en) * | 2018-04-28 | 2018-09-28 | 宜春市金地锂业有限公司 | A kind of dressing activator of lepidolite floatation process |
| CN108910827A (en) * | 2018-10-17 | 2018-11-30 | 杨松 | It is a kind of to prepare hydrogen fluoride process unit |
| CN112062091A (en) * | 2020-09-18 | 2020-12-11 | 宣城亨泰电子化学材料有限公司 | Anhydrous hydrogen fluoride production equipment and production process thereof |
| CN112661115A (en) * | 2020-12-16 | 2021-04-16 | 浙江天采云集科技股份有限公司 | Separation and purification method for deep dehydration and impurity removal of FTrPSA refined by anhydrous HF produced by fluorite method |
| CN113213427A (en) * | 2021-06-18 | 2021-08-06 | 国药集团化学试剂有限公司 | Preparation method of high-purity hydrofluoric acid |
| CN113321185A (en) * | 2021-05-20 | 2021-08-31 | 浙江瑞星氟化工业有限公司 | Production process of anhydrous hydrogen fluoride |
| CN113479845A (en) * | 2021-08-10 | 2021-10-08 | 福建省清流县东莹化工有限公司 | Process and device for preparing anhydrous hydrogen fluoride by recovery method |
-
2012
- 2012-12-31 CN CN201210588971.3A patent/CN103896215A/en active Pending
Cited By (14)
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|---|---|---|---|---|
| CN104071817B (en) * | 2014-07-15 | 2015-11-18 | 辽宁石化职业技术学院 | A kind of method of co-producing sulfuric acid aluminium, white carbon black and Neutral ammonium fluoride |
| CN104071817A (en) * | 2014-07-15 | 2014-10-01 | 辽宁石化职业技术学院 | Method for coproducing aluminium sulfate, white carbon black and ammonium fluoride |
| CN106276801B (en) * | 2016-08-25 | 2019-08-02 | 衢州南高峰化工股份有限公司 | A kind of production equipment and process of anhydrous hydrogen fluoride |
| CN106276801A (en) * | 2016-08-25 | 2017-01-04 | 衢州南高峰化工有限公司 | A kind of production equipment and process of anhydrous hydrogen fluoride |
| CN108298500A (en) * | 2017-01-12 | 2018-07-20 | 洛阳丰瑞氟业有限公司 | A kind of modification scheme improving anhydrous hydrogen fluoride yield and quality production technology |
| CN108147439A (en) * | 2018-02-12 | 2018-06-12 | 沈阳鑫博工业技术股份有限公司 | A kind of device and method that magnesium fluoride is prepared using magnesite powder and fluorite |
| CN108580051A (en) * | 2018-04-28 | 2018-09-28 | 宜春市金地锂业有限公司 | A kind of dressing activator of lepidolite floatation process |
| CN108910827A (en) * | 2018-10-17 | 2018-11-30 | 杨松 | It is a kind of to prepare hydrogen fluoride process unit |
| CN112062091A (en) * | 2020-09-18 | 2020-12-11 | 宣城亨泰电子化学材料有限公司 | Anhydrous hydrogen fluoride production equipment and production process thereof |
| CN112661115A (en) * | 2020-12-16 | 2021-04-16 | 浙江天采云集科技股份有限公司 | Separation and purification method for deep dehydration and impurity removal of FTrPSA refined by anhydrous HF produced by fluorite method |
| CN113321185A (en) * | 2021-05-20 | 2021-08-31 | 浙江瑞星氟化工业有限公司 | Production process of anhydrous hydrogen fluoride |
| CN113213427A (en) * | 2021-06-18 | 2021-08-06 | 国药集团化学试剂有限公司 | Preparation method of high-purity hydrofluoric acid |
| CN113479845A (en) * | 2021-08-10 | 2021-10-08 | 福建省清流县东莹化工有限公司 | Process and device for preparing anhydrous hydrogen fluoride by recovery method |
| CN113479845B (en) * | 2021-08-10 | 2022-12-27 | 福建省清流县东莹化工有限公司 | Process and device for preparing anhydrous hydrogen fluoride by recovery method |
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Application publication date: 20140702 |