CN102951611B - The method that a kind of fluorine-containing waste liquid of phosphatic fertilizer company or hexafluosilicic acid prepare anhydrous hydrogen fluoride - Google Patents
The method that a kind of fluorine-containing waste liquid of phosphatic fertilizer company or hexafluosilicic acid prepare anhydrous hydrogen fluoride Download PDFInfo
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Abstract
The invention discloses the method that a kind of fluorine-containing waste liquid of phosphatic fertilizer company or hexafluosilicic acid prepare anhydrous hydrogen fluoride, the method ammonia（Or ammonium carbonate）With 5%～30% waste gas containing fluoride absorbing liquid or the reaction of fluorine hexafluosilicic acid, pH value 7～8 is reaction end, filters reaction mass and obtains ammonium fluoride solution, for absorbing the SiF in tail gas4, obtain ammonium fluosilicate solution；By ammonium fluosilicate solution evaporation and concentration, solid ammonium fluosilicate after centrifugal filtration, is obtained；Solid ammonium fluosilicate and 92%～99% concentrated sulphuric acid carry out acidolysis reaction, produce SiF4With the mixed gas of HF, mixed gas are scrubbed, purify, obtain anhydrous hydrogen fluoride, SiF after condensation4For preparing ammonium fluosilicate.Waste gas containing fluoride absorbing liquid or the water in hexafluosilicic acid are removed by the present invention in ammonium fluosilicate preparatory phase, are readily obtained anhydrous hydrogen fluoride product；Acidolysis residual liquid returns production of phosphate fertilizer system equivalent and uses；Achieve the effectively utilizes of fluorine resource associated with phosphate rock.
Description
Technical field
The present invention relates in chemical field fluorine chemical industry anhydrous hydrogen fluoride technology of preparing, relate in particular to a kind of profit
The technical method of anhydrous hydrogen fluoride is prepared with the fluorine-containing waste liquid of phosphatic fertilizer company or hexafluosilicic acid.
Background technology：At present, anhydrous hydrogen fluoride for industrial use main production process is with fluorite（Calcium fluoride CaF2）And concentrated sulphuric acid
For raw material, 500 DEG C are heated to, reaction generates hydrogen fluoride gas, by distilation, anhydrous hydrogen fluoride is obtained after liquefaction, react
The calcium sulfate for generating afterwards is used as industrial waste residue disposal.With hexafluosilicic acid as the technology of raw material production anhydrous hydrogen fluoride, both at home and abroad except
Guizhou Wengfu Lantian Fluoride Chemicals Co., Ltd. is produced outside anhydrous hydrogen fluoride using hexafluosilicic acid using sulphuric acid pyrolysismethod, is not also had
Other ripe industrialization technologies.
For a long time, industry thinks that fluorite is the main source of fluorine resource always.Whole world fluorite reserves are about 600,000,000
Ton, is calculated by 50% Oil repellent, also only about 300,000,000 tons of fluorine total amount.And about 60,000,000,000 tons of rock phosphate in powder reserves known to the world, phosphorus
Oil repellent in Ore is 2%～4%, and corresponding fluorine total amount is 1,200,000,000 ~ 2,400,000,000 tons.China's fluorite resource through verifying
Reserves (Ore is based on national single fluorite average grade 54%) have 1.55 × 105Kt, and China's fluorine resource associated with phosphate rock reserves
It is equivalent to 2.12 × 106～2.59 × 106Fluorine stock number in kt fluorite ores, be China verified fluorite reserves 13.67～
16.71 times.Up to more than 5,000 ten thousand tons, association fluorine has more than 150 ten thousand tons to the rock phosphate in powder amount of annual exploitation.On the other hand, fluorite is a kind of
Non-renewable strategic resources, country have had been carried out no longer providing new fluorite production licence, and carry out quota outlet（Go out
Mouth quota is also being reduced year by year）Deng relevant policies.With the minimizing of fluorite resource, day is becoming tight by Fluorspar Powder supply, and fluorite
The price of powder also will be high all the way, and this will be extremely limited will Fluorspar Powder-Production By Sulfuric Acid Process Fluohydric acid. or anhydrous hydrogen fluoride
Even stop production.Therefore, fluorine resource in effectively utilizes phosphorus ore, with hexafluosilicic acid as raw material production anhydrous hydrogen fluoride, is China's fluorination work
The inevitable choice of sustainable development.
With the high speed development of Chinese fluorine chemical industry, fluorite resource is further exhausted, rationally recycles in phosphorus ore and enriches
Fluorine resource day by day important.The present invention prepares the various patented technologies of anhydrous hydrogen fluoride by hexafluosilicic acid inside and outside comparator, proposes
This technology method.
The current hexafluosilicic acid using phosphatic fertilizer company by-product is more come the patented technology for producing fluohydric acid gas, is broadly divided into direct method
And indirect method, direct method is to prepare fluohydric acid gas using sulphuric acid Direct Resolution hexafluosilicic acid；Indirect method is that hexafluosilicic acid is converted into fluorine first
Change the fluoride salts such as ammonium, then fluohydric acid gas is prepared with sulfuric acid reaction.Whether direct method and indirect method, being intended to suffer from a problem that is
From hexafluosilicic acid to anhydrous hydrogen fluoride, the water in raw material how is removed, obtain anhydrous product.Existing a lot of technology precisely due to
Fail to remove the water in raw material, can only obtain water Fluohydric acid..Therefore, anhydrous hydrogen fluoride, dehydration technique are produced using hexafluosilicic acid
It is crucial.
Content of the invention：
It is an object of the invention to provide the method that a kind of fluorine-containing waste liquid of phosphatic fertilizer company or hexafluosilicic acid prepare anhydrous hydrogen fluoride, will
Water in waste gas containing fluoride absorbing liquid or hexafluosilicic acid is excluded by concentrating ammonium fluosilicate, then with concentrated sulphuric acid acidolysis solid ammonium fluosilicate rank
Section can be obtained the very low fluohydric acid gas of water content and Silicon fluoride. mixed gas, be readily obtained anhydrous hydrogen fluoride product；Acidolysis residual liquid
Return production of phosphate fertilizer system to utilize.The waste gas containing fluoride absorbing liquid in production of phosphate fertilizer or hexafluosilicic acid is made to be utilized effectively.
The technical method of the present invention is as follows：
（1）Use ammonia（Or ammonium carbonate）React with the waste gas containing fluoride absorbing liquid of 5%～30%W/W or hexafluosilicic acid, control ph 7～
8 is reaction end, generates ammonium fluoride and silicon dioxide, filters ammonolysis reaction material and obtains ammonium fluoride solution and silicon dioxide by-product
Product.Raw material of the ammonium fluoride solution as subsequent technique, the supplement that silicon dioxide wash water is used for the fluorine absorption system of Phosphoric Acid Concentration are molten
Liquid, silicon dioxide side-product further can be recycled.
The main chemical reactions principle being related to is：
（2）Above-mentioned steps（1）The ammonium fluoride solution of middle production, for absorption step（5）In tail gas, NH4In F and tail gas
SiF4Reaction, obtains ammonium fluosilicate solution；
The main chemical reactions principle being related to is：
①
②
（3）Above-mentioned steps（2）In the ammonium fluosilicate solution that obtains through low pressure evaporation and concentration, obtain solid ammonium fluosilicate.Steam
It is 55kPa～80kPa to send out vacuum, and temperature of charge is 70 DEG C～50 DEG C.
（4）Above-mentioned steps（3）In the solid ammonium fluosilicate that obtains, with H2SO4Content be 92%～99% concentrated sulphuric acid in high temperature
Under the conditions of carry out acidolysis reaction, produce SiF4With the mixed gas of HF, the return production of phosphate fertilizer system equivalent use of acidolysis residual liquid.Sulfur
Sour addition is with H2SO4It is calculated as 100%～150%W/W of theoretical amount；Sulphuric acid is with H2SO4Be calculated as theoretical amount 100%～
150%W/W；Acidolysis is volatilized SiF under vacuum4And HF, in 55kPa～85kPa, temperature control is at 120 DEG C for vacuum degree control
～140 DEG C；When acidolysis carries out volatilization SiF at ambient pressure4During with HF, then temperature should be controlled at 140 DEG C～175 DEG C.
The main chemical reactions principle being related to is：
（5）Above-mentioned steps（4）In the fluohydric acid gas that obtains and Silicon fluoride. mixed gas scrubbed, purify, after condensation
Anhydrous hydrogen fluoride is arrived, in tail gas, mainly contains SiF4Gas.Indication concentration of the present invention adopts concentration expressed in percentage by weight.
Waste gas containing fluoride absorbing liquid or the water in hexafluosilicic acid are removed by the present invention in ammonium fluosilicate preparatory phase, in acidolysis fluorine
Change hydroformylation stage and the very low acidolysis gas of water content can be obtained, be readily obtained anhydrous hydrogen fluoride product.Acidolysis residual liquid returns phosphate fertilizer life
Produce system equivalent to use.Side-product silica impurity content is low, it is easy to carry out deep processing into filler white carbon.Concentration is produced
Only it is a small amount of fluorine that liquid foam is taken out of in waste water, it is easy to process.This invention technology achieves effective profit of fluorine resource associated with phosphate rock
With.
Description of the drawings：
Process flow diagrams of the Fig. 1 for the inventive method.Schematic diagram mainly includes：Step（1）Use ammonia（Or ammonium carbonate）
The ammonolysis reaction carried out with waste gas containing fluoride absorbing liquid or hexafluosilicic acid（Ⅰ）；Step（2）Middle ammonium fluoride solution absorbs SiF in tail gas4Gas
The tail gas absorption of body production ammonium fluosilicate solution, ammonium fluosilicate solution production（Ⅱ）；Step（3）Middle ammonium fluosilicate solution adds dense
The ammonium fluosilicate solution concentration of contracting（Ⅲ）；Step（4）Middle solid ammonium fluosilicate carries out the solid fluorine silicon of acidolysis reaction with concentrated sulphuric acid
Sour ammonium acidolysis（Ⅳ）；SiF4, the condensation of HF gases, refined after obtain HF condensations, the rectification of anhydrous hydrogen fluoride（Ⅴ）.
Specific embodiment：
Embodiment 1
Use ammonia（Or ammonium carbonate）With 20% fluorine hexafluosilicic acid react, control ph 7.5 be reaction end, generate ammonium fluoride and
Silicon dioxide, filters ammonolysis reaction material and obtains ammonium fluoride solution and silicon dioxide side-product；It is used for absorbing by ammonium fluoride solution
SiF in tail gas4, obtain ammonium fluosilicate solution；Ammonium fluosilicate solution obtains solid ammonium fluosilicate through low pressure evaporation and concentration, and evaporation is true
Reciprocal of duty cycle is 75kPa, about 55 DEG C～58 DEG C of temperature of charge.Content consolidating more than 92% is obtained after solid ammonium fluosilicate centrifuge dehydration
Body ammonium fluosilicate；Solid ammonium fluosilicate and 98% concentrated sulphuric acid carry out acidolysis reaction production SiF4With the mixed gas of HF, sulphuric acid adds
Enter amount with H2SO4Be calculated as the 120% of theoretical amount, acidolysis is volatilized fluohydric acid gas under vacuum, vacuum degree control 55kPa～
80kPa, reaction temperature are controlled at 140 DEG C～120 DEG C；Acidolysis residual liquid returns production of phosphate fertilizer system equivalent and uses；Acidolysis is obtained
SiF4Anhydrous hydrogen fluoride is obtained after, purification scrubbed with the mixed gas of HF, condensation；Mainly contain SiF in cool solidifying rear tail gas4Gas,
Tail gas is used for preparing ammonium fluosilicate；Will obtain after condensation anhydrous hydrogen fluoride obtain after rectification HF contents more than 99.90% anhydrous
Fluohydric acid gas finished product.
Anhydrous hydrogen fluoride per ton（100%HF）The norm quota of consumption
Fluorine yield is more than 88%.
Embodiment 2
Except acidolysis process is using the fluohydric acid gas that volatilizees at ambient pressure, reaction temperature control is outer at about 170 DEG C, remaining same embodiment
1.
Claims (2)
1. the method that a kind of fluorine-containing waste liquid of phosphatic fertilizer company or hexafluosilicic acid prepare anhydrous hydrogen fluoride, is characterized in that：Waste gas containing fluoride is inhaled
Receive liquid or the water in hexafluosilicic acid is removed in ammonium fluosilicate preparatory phase, acidolysis gas can be obtained in acidolysis system fluorination hydroformylation stage, makes
Anhydrous hydrogen fluoride product is obtained, follow these steps to carry out：
(1) with the waste gas containing fluoride absorbing liquid or hexafluosilicic acid reaction of ammonia or ammonium carbonate and 5%～30%W/W, control ph 7～8 is
Reaction end, generates ammonium fluoride and silicon dioxide, filters ammonolysis reaction material and obtains ammonium fluoride solution and silicon dioxide side-product,
Chemical equation is as follows：
(2) ammonium fluoride solution produced in above-mentioned steps (1), for the tail gas in absorption step (5), obtains ammonium fluosilicate molten
Liquid, chemical equation are as follows：
①
②
(3) ammonium fluosilicate solution obtained in above-mentioned steps (2) vacuum be 55kPa～80kPa, temperature of charge be 70 DEG C～
Under conditions of 50 DEG C, evaporation and concentration produces ammonium fluosilicate crystal, obtains solid ammonium fluosilicate after centrifugal filtration；
(4) the solid ammonium fluosilicate obtained in above-mentioned steps (3), with H2SO4Content is that 92%～99% concentrated sulphuric acid carries out acidolysis
Reaction, produces SiF4Mixed gas with HF；Sulphuric acid is with H2SO4It is calculated as 120%～130%W/W of theoretical amount；Acidolysis
Volatilize SiF under vacuum4And HF, in 70kPa～80kPa, temperature control is at 120 DEG C～140 DEG C for vacuum degree control；Work as acid
Solution carries out volatilization SiF at ambient pressure4During with HF, at 140 DEG C～175 DEG C, chemical equation is as follows for temperature control：
(5) SiF obtained in above-mentioned steps (4)4Scrubbed with the mixed gas of HF, purify, condensation, refined after obtain anhydrous fluorine
Change hydrogen, in tail gas, mainly contain SiF4Return and prepare ammonium fluosilicate；
In step (1), the wash water of washing silicon dioxide is used as the make-up solution of Phosphoric Acid Concentration fluorine absorption system；
The acidolysis residual liquid of step (4) returns production of phosphate fertilizer system equivalent and uses；
Mainly contain SiF in the tail gas of step (5)4Gas, sends into step (2) and is absorbed with the ammonium fluoride solution of step (1).
2. the method that a kind of fluorine-containing waste liquid of phosphatic fertilizer company or hexafluosilicic acid prepare anhydrous hydrogen fluoride as claimed in claim 1, its are special
Levy is that the acidolysis of step (4) can also be volatilized SiF at ambient pressure4And HF, temperature control is at 160 DEG C～170 DEG C.
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Families Citing this family (15)
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| CN104445074B (en) * | 2014-12-11 | 2016-09-14 | 云南省化工研究院 | The method that dilute hexafluosilicic acid prepares anhydrous hydrogen fluoride coproduction Silicon fluoride. is processed by solvent extraction |
| CN106006560A (en) * | 2016-05-23 | 2016-10-12 | 禄丰天宝磷化工有限公司 | Method for preparing hydrogen fluoride in feed grade calcium hydrophosphate production process |
| CN106145043A (en) * | 2016-06-29 | 2016-11-23 | 云南磷化集团有限公司 | The method that the fluorine-containing waste liquid of a kind of phosphorous chemical industry prepares low concentration hydrofluoric acid |
| CN106185817A (en) * | 2016-07-12 | 2016-12-07 | 中南大学 | A kind of method reclaiming Fluohydric acid. from fluorine-containing silicic acid waste water |
| CN108996510A (en) * | 2018-06-25 | 2018-12-14 | 确成硅化学股份有限公司 | The preparation method of dustless easy dispersed silicon dioxide |
| CN109179328A (en) * | 2018-08-29 | 2019-01-11 | 福建瓮福蓝天氟化工有限公司 | A kind of decoloration process of phosphoric acid fluosilicic acid as byproduct production anhydrous hydrogen fluoride |
| CN109353988A (en) * | 2018-11-12 | 2019-02-19 | 贵州开磷氟硅化工有限责任公司 | The method that ammonium fluoride and the concentrated sulfuric acid are mixed with high concentration of hydrofluoric acid |
| CN109574017A (en) * | 2018-11-23 | 2019-04-05 | 贵州开磷氟硅化工有限责任公司 | A method of SiF4 and anhydrous hydrogen fluoride are prepared by raw material of fluosilicic acid |
| CN110950359A (en) * | 2020-01-07 | 2020-04-03 | 贵州瓮福蓝天氟化工股份有限公司 | Method for preparing sodium fluoride and by-product high-performance white carbon black |
| CN111153387A (en) * | 2020-03-03 | 2020-05-15 | 衢州市鼎盛化工科技有限公司 | Method and equipment for recovering fluorine-containing waste liquid of acid-washed coal |
| CN112320803B (en) * | 2020-10-27 | 2022-05-13 | 贵州省化工研究院 | Method for producing solid ammonium fluosilicate by using fluosilicic acid in phosphoric acid |
| CN114988920B (en) * | 2022-04-20 | 2023-01-13 | 贵州新东浩化工材料科技有限公司 | Method for utilizing fluorine and silicon resources in phosphate ore in grading manner |
| US11891344B2 (en) | 2022-04-20 | 2024-02-06 | Chtem Limited | Methods for graded utilization of fluorine and silicon resources in phosphate ores |
| CN115072666B (en) * | 2022-06-23 | 2023-08-18 | 中石化南京工程有限公司 | System and method for preparing anhydrous hydrogen fluoride from fluosilicic acid |
| CN115010092A (en) * | 2022-07-20 | 2022-09-06 | 湖北九宁化学科技有限公司 | Method for recycling CVD dust in semiconductor industry |
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