CN113479907A - Crystallization method of ammonium fluoride or ammonium bifluoride - Google Patents
Crystallization method of ammonium fluoride or ammonium bifluoride Download PDFInfo
- Publication number
- CN113479907A CN113479907A CN202110801403.6A CN202110801403A CN113479907A CN 113479907 A CN113479907 A CN 113479907A CN 202110801403 A CN202110801403 A CN 202110801403A CN 113479907 A CN113479907 A CN 113479907A
- Authority
- CN
- China
- Prior art keywords
- liquid
- reaction
- solution
- ammonia
- ammonium
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- MIMUSZHMZBJBPO-UHFFFAOYSA-N 6-methoxy-8-nitroquinoline Chemical compound N1=CC=CC2=CC(OC)=CC([N+]([O-])=O)=C21 MIMUSZHMZBJBPO-UHFFFAOYSA-N 0.000 title claims abstract description 39
- DDFHBQSCUXNBSA-UHFFFAOYSA-N 5-(5-carboxythiophen-2-yl)thiophene-2-carboxylic acid Chemical compound S1C(C(=O)O)=CC=C1C1=CC=C(C(O)=O)S1 DDFHBQSCUXNBSA-UHFFFAOYSA-N 0.000 title claims abstract description 34
- 238000002425 crystallisation Methods 0.000 title claims abstract description 31
- 238000006243 chemical reaction Methods 0.000 claims abstract description 118
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims abstract description 84
- 239000000463 material Substances 0.000 claims abstract description 82
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 claims abstract description 72
- 239000007788 liquid Substances 0.000 claims abstract description 64
- 239000013078 crystal Substances 0.000 claims abstract description 44
- 239000007921 spray Substances 0.000 claims abstract description 43
- 238000001816 cooling Methods 0.000 claims abstract description 33
- 238000004519 manufacturing process Methods 0.000 claims abstract description 30
- 238000000034 method Methods 0.000 claims abstract description 30
- 239000012452 mother liquor Substances 0.000 claims abstract description 30
- 239000007789 gas Substances 0.000 claims abstract description 24
- 229910000040 hydrogen fluoride Inorganic materials 0.000 claims abstract description 22
- 238000005086 pumping Methods 0.000 claims abstract description 22
- 238000002479 acid--base titration Methods 0.000 claims abstract description 15
- 230000008025 crystallization Effects 0.000 claims abstract description 13
- 238000012544 monitoring process Methods 0.000 claims abstract description 7
- 239000000243 solution Substances 0.000 claims description 34
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 33
- 239000012670 alkaline solution Substances 0.000 claims description 32
- 229910021529 ammonia Inorganic materials 0.000 claims description 26
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 24
- 239000000523 sample Substances 0.000 claims description 13
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 12
- 239000000203 mixture Substances 0.000 claims description 10
- 238000004806 packaging method and process Methods 0.000 claims description 10
- 230000007797 corrosion Effects 0.000 claims description 9
- 238000005260 corrosion Methods 0.000 claims description 9
- 239000012295 chemical reaction liquid Substances 0.000 claims description 8
- XJRPTMORGOIMMI-UHFFFAOYSA-N ethyl 2-amino-4-(trifluoromethyl)-1,3-thiazole-5-carboxylate Chemical compound CCOC(=O)C=1SC(N)=NC=1C(F)(F)F XJRPTMORGOIMMI-UHFFFAOYSA-N 0.000 claims description 8
- KJFMBFZCATUALV-UHFFFAOYSA-N phenolphthalein Chemical compound C1=CC(O)=CC=C1C1(C=2C=CC(O)=CC=2)C2=CC=CC=C2C(=O)O1 KJFMBFZCATUALV-UHFFFAOYSA-N 0.000 claims description 8
- 239000002253 acid Substances 0.000 claims description 7
- 239000007853 buffer solution Substances 0.000 claims description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 5
- 238000010521 absorption reaction Methods 0.000 claims description 5
- 239000010439 graphite Substances 0.000 claims description 5
- 229910002804 graphite Inorganic materials 0.000 claims description 5
- 238000002156 mixing Methods 0.000 claims description 5
- 239000004033 plastic Substances 0.000 claims description 5
- 238000005070 sampling Methods 0.000 claims description 5
- 238000003756 stirring Methods 0.000 claims description 5
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 claims description 4
- RQPZNWPYLFFXCP-UHFFFAOYSA-L barium dihydroxide Chemical compound [OH-].[OH-].[Ba+2] RQPZNWPYLFFXCP-UHFFFAOYSA-L 0.000 claims description 4
- 229910001863 barium hydroxide Inorganic materials 0.000 claims description 4
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 claims description 4
- 239000000920 calcium hydroxide Substances 0.000 claims description 4
- 229910001861 calcium hydroxide Inorganic materials 0.000 claims description 4
- 239000008098 formaldehyde solution Substances 0.000 claims description 4
- 229910052751 metal Inorganic materials 0.000 claims description 4
- 239000002184 metal Substances 0.000 claims description 4
- 230000007935 neutral effect Effects 0.000 claims description 4
- 239000012086 standard solution Substances 0.000 claims description 4
- 238000004643 material aging Methods 0.000 claims description 3
- 239000012488 sample solution Substances 0.000 claims description 3
- 239000002699 waste material Substances 0.000 abstract description 10
- 239000002245 particle Substances 0.000 abstract description 6
- 239000002994 raw material Substances 0.000 abstract description 6
- 238000012258 culturing Methods 0.000 abstract description 3
- 238000000926 separation method Methods 0.000 abstract description 3
- 150000001875 compounds Chemical class 0.000 abstract description 2
- 238000001514 detection method Methods 0.000 description 12
- 238000004448 titration Methods 0.000 description 12
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 3
- 239000011521 glass Substances 0.000 description 3
- 239000007769 metal material Substances 0.000 description 3
- 229910000976 Electrical steel Inorganic materials 0.000 description 2
- 229910000861 Mg alloy Inorganic materials 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 230000002378 acidificating effect Effects 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 238000000889 atomisation Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000005119 centrifugation Methods 0.000 description 2
- 239000000919 ceramic Substances 0.000 description 2
- 238000005536 corrosion prevention Methods 0.000 description 2
- 229910000856 hastalloy Inorganic materials 0.000 description 2
- 239000007791 liquid phase Substances 0.000 description 2
- 239000003921 oil Substances 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 238000005507 spraying Methods 0.000 description 2
- 231100000331 toxic Toxicity 0.000 description 2
- 230000002588 toxic effect Effects 0.000 description 2
- FRWYFWZENXDZMU-UHFFFAOYSA-N 2-iodoquinoline Chemical compound C1=CC=CC2=NC(I)=CC=C21 FRWYFWZENXDZMU-UHFFFAOYSA-N 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- 229910004074 SiF6 Inorganic materials 0.000 description 1
- 210000000683 abdominal cavity Anatomy 0.000 description 1
- 238000010306 acid treatment Methods 0.000 description 1
- 238000003915 air pollution Methods 0.000 description 1
- 230000029936 alkylation Effects 0.000 description 1
- 238000005804 alkylation reaction Methods 0.000 description 1
- SNAAJJQQZSMGQD-UHFFFAOYSA-N aluminum magnesium Chemical compound [Mg].[Al] SNAAJJQQZSMGQD-UHFFFAOYSA-N 0.000 description 1
- LDDQLRUQCUTJBB-UHFFFAOYSA-N ammonium fluoride Chemical compound [NH4+].[F-] LDDQLRUQCUTJBB-UHFFFAOYSA-N 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000003556 assay Methods 0.000 description 1
- KVBCYCWRDBDGBG-UHFFFAOYSA-N azane;dihydrofluoride Chemical compound [NH4+].F.[F-] KVBCYCWRDBDGBG-UHFFFAOYSA-N 0.000 description 1
- 229910052790 beryllium Inorganic materials 0.000 description 1
- ATBAMAFKBVZNFJ-UHFFFAOYSA-N beryllium atom Chemical compound [Be] ATBAMAFKBVZNFJ-UHFFFAOYSA-N 0.000 description 1
- LTPBRCUWZOMYOC-UHFFFAOYSA-N beryllium oxide Inorganic materials O=[Be] LTPBRCUWZOMYOC-UHFFFAOYSA-N 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 239000012459 cleaning agent Substances 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000000645 desinfectant Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000005562 fading Methods 0.000 description 1
- 238000000855 fermentation Methods 0.000 description 1
- 230000004151 fermentation Effects 0.000 description 1
- 125000001153 fluoro group Chemical class F* 0.000 description 1
- 238000005246 galvanizing Methods 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 230000017525 heat dissipation Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- 238000006317 isomerization reaction Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 239000003595 mist Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 1
- 239000010452 phosphate Substances 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 239000003755 preservative agent Substances 0.000 description 1
- 230000002335 preservative effect Effects 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01C—AMMONIA; CYANOGEN; COMPOUNDS THEREOF
- C01C1/00—Ammonia; Compounds thereof
- C01C1/16—Halides of ammonium
- C01C1/162—Ammonium fluoride
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01C—AMMONIA; CYANOGEN; COMPOUNDS THEREOF
- C01C1/00—Ammonia; Compounds thereof
- C01C1/16—Halides of ammonium
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/80—Compositional purity
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Removal Of Specific Substances (AREA)
Abstract
The invention belongs to the technical field of compound production, and particularly relates to a crystallization method of ammonium fluoride or ammonium bifluoride, which comprises the steps of crystallizing by adopting an air-cooled spray cooling tower, reacting in batches by taking anhydrous hydrogen fluoride and liquid ammonia as raw materials, monitoring a reaction end point by a rapid acid-base titration method, pumping a reacted material to the top of the spray tower, falling from the top of the spray tower through a distributor, sequentially passing through two layers of demisters with opposite directions, then re-entering a circulating tank, cooling, then sending to a crystal growing tank for culturing, and separating to obtain a crystal finished product; meanwhile, the mother liquor is recycled after solid-liquid separation, and tail gas is discharged after passing through a three-stage spray tower and the mother liquor. The invention adopts the air-cooled spray cooling tower for crystallization, the cooling speed is high, the yield of finished products is high, and the obtained crystal particles are uniform, compact and stable and meet the requirements of first-class products of national standards; meanwhile, liquid and tail gas in the production process are uniformly and intensively recovered and recycled, no waste liquid or waste residue is generated, and zero-emission production is basically achieved.
Description
Technical Field
The invention belongs to the technical field of compound production, and particularly relates to a crystallization method of ammonium fluoride or ammonium bifluoride.
Background
Ammonium fluoride is a white needle crystal which is easy to absorb moisture, soluble in cold water, slightly soluble in ethanol, decomposed into ammonia and hydrogen fluoride by heating, decomposed into ammonia and ammonium bifluoride in hot water, the aqueous solution of the ammonium bifluoride is acidic and can corrode glass, the relative density is 1.015, the ammonium bifluoride is toxic and has half of death amount (rat, abdominal cavity) of 32mg/kg, and the ammonium bifluoride is corrosive and can be used as a chemical reagent, a glass etchant (used together with hydrofluoric acid), a disinfectant and a preservative for fermentation industry, a solvent for preparing metallic beryllium from beryllium oxide and a surface treating agent for silicon steel plates, and also can be used for manufacturing ceramics, magnesium alloys, cleaning and descaling of boiler water supply systems and steam generating systems, and acid treatment of oil field gravels and also can be used as alkylation and isomerization catalyst components. Ammonium bifluoride is an important inorganic fluorine salt, white orthorhombic crystal, has the specific gravity of 1.52, the melting point of 124.6 ℃, is easy to deliquesce and agglomerate, is soluble in water and slightly soluble in alcohol, is decomposed into ammonia and ammonium bifluoride in hot water, is decomposed into ammonia and hydrogen fluoride when being heated, has acidic reaction in aqueous solution, can corrode glass and is toxic, is mainly used for passivating metal in phosphate or galvanizing and nickel plating, is used for washing metal to activate the surface, performing rust prevention treatment on the surface of silicon steel plate, utilizing the characteristics of dissolving silica and silicate, is used for acidizing sandstone in oil field by-edge wells to improve the yield, and can also be used for manufacturing an oxidant of ceramic cleaning agents and aluminum-magnesium alloys, removing silicate and other scales in a steam generating system of a boiler water supply system.
Currently, ammonium fluoride or ammonium bifluoride is mainly produced by a liquid phase method, and crystallization methods of the liquid phase method are various and generally divided into a natural cooling mode and a crystallizer mode. And natural cooling crystallization has long crystallization time, serious open air pollution, slow closed heat dissipation and longer crystallization period, and simultaneously, crystal particles formed by natural cooling crystallization have uneven particle size and large deviation.
Meanwhile, ammonium bifluoride has strong corrosivity, equipment is seriously corroded by using a crystallizer made of conventional metal materials, and the I-path plastic material is adopted, so that the plastic has poor heat conductivity and low heat exchange efficiency. Adopt pressurization atomizing spray column among the patent CN201510159229.4, utilize the air to cool off, but the material spraying gets into the tower top, and the air outlet also is located the tower top, and the liquid droplet after the atomizing is taken out spray column by the air current very easily, gets into the tail gas system, reduces the finished product yield. Even the entrained material droplets crystallize in the off-gas line, which can lead to line plugging as production batches increase.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a crystallization method of ammonium fluoride or ammonium bifluoride, which adopts an air-cooled spray cooling tower for crystallization, has high cooling speed and high finished product yield, and obtains uniform, compact and stable crystal particles; the whole process is completed under the condition of closed micro negative pressure, the production environment is good, liquid and tail gas in the production process are uniformly and intensively recycled and recycled, no waste liquid or waste residue is generated, and zero-emission production is basically achieved.
In order to achieve the above object, the present invention provides a crystallization method of ammonium fluoride or ammonium bifluoride, wherein the crystallization method adopts an air-cooled spray cooling tower for crystallization, and specifically comprises the following steps:
s1, pumping mother liquor or water into a reaction kettle with a graphite tube array cooling tower, and dividing the amount of anhydrous hydrogen fluoride and the amount of liquid ammonia into a plurality of batches respectively according to theoretical feeding amount;
s2, introducing anhydrous hydrogen fluoride with a first batch of feeding amount into the reaction kettle in a water cooling state, slowly introducing liquid ammonia with the first batch of feeding amount into the reaction kettle, and controlling the flow of the liquid ammonia to ensure that the temperature of a reaction system does not exceed 95 ℃; preferably, when the ammonium fluoride is produced, the temperature of the reaction system does not exceed 90 ℃; when the ammonium bifluoride is produced, the temperature of the reaction system does not exceed 95 ℃.
S3, after ammonia introduction is finished in S2, introducing anhydrous hydrogen fluoride with a second batch of material quantity into the reaction kettle, keeping the temperature of a reaction system not more than 95 ℃, introducing liquid ammonia with a second batch of material quantity into the reaction kettle, keeping the temperature of the reaction system not more than 95 ℃, and sequentially and alternately reacting; preferably, when the ammonium fluoride is produced, the temperature of the reaction system does not exceed 90 ℃; when the ammonium bifluoride is produced, the temperature of the reaction system does not exceed 95 ℃.
S4, after the reaction of S3, sampling from the reaction liquid, monitoring the reaction end point by adopting a rapid acid-base titration method, and controlling the feeding amount of anhydrous hydrofluoric acid or liquid ammonia according to the monitoring result until the reaction is complete;
s5, pumping the completely reacted materials in the S4 reaction kettle to a circulating tank filled with mother liquor in advance, reducing the temperature of the materials to be below 80 ℃, and stirring and mixing;
s6, pumping the material in the circulating tank in the S5 to the top of the spray tower, enabling the material to fall from the top of the spray tower through a distributor to enable the material to be in contact with cold air from bottom to top in the spray tower, sequentially passing through two layers of demisters with opposite directions, re-entering the circulating tank from the bottom of the spray tower, and circularly cooling the material in such a way to enable the temperature of the material to be reduced to 35-45 ℃; preferably, when the ammonium fluoride is produced, the temperature of the material is reduced to about 35 ℃; when producing ammonium bifluoride, the material temperature is reduced to about 40 ℃.
S7, feeding the cooled material in the S6 circulating tank to a crystal growing tank to grow crystals;
s8, pumping the crystals cultured in the S7 crystal growing tank to a horizontal centrifuge, feeding the crystals into a packaging tank through a self-unloading material, and packaging to obtain a packaged finished product;
s9, automatically flowing the mother liquor separated in the S8 to a solid-liquid separator, allowing the upper clear liquid to enter a mother liquor tank, combining the lower solid-liquid mixture with the liquid separated by the gas-liquid separator in the tail gas system, and then returning the mixture to a circulation tank;
and S10, combining tail gas of equipment facilities, sending the tail gas into a three-stage spray tower, and emptying after mother liquor absorption.
Further, in the above technical scheme, in S1, anhydrous hydrogen fluoride and liquid ammonia are divided into 2 to 5 batches, respectively.
Further, when ammonium fluoride is produced in the above technical scheme S4, the rapid acid-base titration method is: taking 2mL of reaction solution, putting the reaction solution into a colorimetric tube added with 50mL of water in advance, and dripping 2 drops of 1g/L bromocresol purple indicator solution to obtain sample solution; (1) when the sample liquid is purple, comparing with the standard liquid, if the purple of the sample liquid is deeper than the standard liquid, excessive ammonia is contained in the reaction system, and anhydrous hydrofluoric acid is not required to be supplemented, and if the purple of the sample liquid is lighter than the standard liquid, the reaction is complete; (2) when the sample liquid is yellow, titrating to purple with 1mol/L alkaline solution, and recording the consumed volume of the alkaline solution as V:
when V is more than 0.2mL, the ammonia in the reaction system is insufficient, and ammonia needs to be supplemented;
the reaction was complete when 0< V <0.2 ml.
Further, in the technical scheme, the standard solution is prepared by measuring 50mL of buffer solution with pH of 6.8, placing the buffer solution in a 50mL colorimetric tube, adding 2 drops of 1g/L bromocresol purple indicator solution, and shaking up.
Further, when ammonium acid fluoride is produced in the above technical scheme S4, the rapid acid-base titration method is: taking 2mL of reaction liquid, adding 50mL of water, dripping 2-3 drops of 10g/L phenolphthalein indicator liquid for the first time, titrating to light red by using 1mol/L alkaline solution, and recording the volume consumed by the alkaline solution as V1; adding 20mL of neutral formaldehyde solution for the second time, titrating the solution to light red by using 1mol/L alkaline solution, and recording the consumption volume of the alkaline solution as V2;
when the ratio (V1-V2) >0.5, the ammonia in the reaction system is insufficient, and ammonia needs to be supplemented;
when the reaction system is (V1-V2) <0, acid in the reaction system is insufficient, and anhydrous hydrofluoric acid is required to be supplemented;
when 0< (V1-V2) <0.5, the reaction was complete.
Further, the alkaline solution in the technical scheme is any one of sodium hydroxide, potassium hydroxide, calcium hydroxide and barium hydroxide.
Further, in the above technical solution S6, the distributor is made of a plastic material or a metal material resistant to corrosion by hydrofluoric acid, and preferably, a hastelloy metal material is selected; the demister is a cyclone plate or a baffle plate. The distributor is used in the technical scheme to enable the materials to uniformly enter the spray tower, the materials are not easy to form mist and are taken away by air flow, and the cyclone plate further weakens the possibility of atomization in the falling process of the materials.
Further, the crystal growing time in the technical scheme S7 is not more than 24 h.
Further, in the above technical solution S8, the horizontal centrifuge is an automatic discharge centrifuge made of hydrofluoric acid corrosion-resistant material or hydrofluoric acid corrosion-resistant material.
Furthermore, the crystallization method in the technical scheme is completed under the condition of closed micro-negative pressure.
The invention has the beneficial effects that:
1. the invention adopts the air-cooled spray cooling tower for crystallization, the cooling speed is high, the material can be uniformly distributed by using the distributor, atomized liquid drops are not easy to be formed and taken away by airflow, meanwhile, demisters such as a rotational flow plate and the like can further weaken the atomization level of the material, and the yield of finished products is high;
2. according to the invention, the amount of anhydrous hydrofluoric acid and liquid ammonia is divided into a plurality of batches for reaction, the input amount of raw materials is well controlled, and the reaction is full; meanwhile, the problems of over-quick temperature rise of a reaction system and escape of raw materials due to the simultaneous existence of a large amount of anhydrous hydrofluoric acid and liquid ammonia are solved, the temperature is controlled, and no raw material is wasted;
3. the invention adopts a rapid acid-base titration method to carry out end point control, has simple, convenient, rapid and accurate operation and stable product quality;
4. the invention can reasonably configure the number of the reaction kettles and the crystal growing tanks, can realize continuous production, and has flexible production mode and high efficiency;
5. the whole production process is simple to operate and easy to control, the reaction end point can be accurately controlled, the crystal particles of the product are uniform and compact, the product quality is kept stable for a long time, and the requirements of first-class products in national standards are met;
6. the whole production process is completed under the condition of closed micro negative pressure, so that the production environment of a workshop is greatly improved, and the method is safe and environment-friendly; materials are conveyed through a pump and a pipeline in the production process, so that the labor intensity is reduced; meanwhile, liquid and tail gas in the production process are uniformly and intensively recovered and recycled, no waste liquid or waste residue is generated, and zero-emission production is basically achieved.
Drawings
FIG. 1 is a flow chart of the production process of the present invention.
Detailed Description
The experimental procedures in the following examples are conventional unless otherwise specified. The raw materials in the following examples are all commercially available products and are commercially available, unless otherwise specified.
FIG. 1 is a production process flow diagram of the present invention, in which an air-cooled spray cooling tower is used for crystallization, anhydrous hydrogen fluoride and liquid ammonia are used as raw materials, the reaction is carried out in batches, the reaction end point is monitored by a rapid acid-base titration method, then the reacted materials are pumped to the top of the spray tower, the materials are mixed with cold mother liquor in a circulation tank, the temperature is reduced to below 80 ℃, the materials fall from the top of the tower through a distributor, sequentially pass through two layers of demisters with opposite directions, and then enter the circulation tank again from the bottom of the tower, when the temperature of the materials is reduced to about 40 ℃, the spraying is stopped, the materials are cooled and then sent to a crystal growing tank for culture, and crystal finished products are obtained through separation; meanwhile, the mother liquor is recycled after solid-liquid separation, and the tail gas is exhausted after being absorbed by the three-stage spray tower and the mother liquor.
The method specifically comprises the following steps:
s1, pumping mother liquor or water into a reaction kettle with a graphite tube array cooling tower, and dividing the amount of anhydrous hydrogen fluoride and the amount of liquid ammonia into a plurality of batches respectively according to theoretical feeding amount; specifically, the method can be divided into 2 batches, 3 batches, 4 batches and 5 batches, and can be set according to the amount of fed materials, and if the batches are too many, the valves of anhydrous hydrofluoric acid and liquid ammonia are closed too frequently and are easy to damage; if the batch is too little, the temperature is not easy to control, and the temperature is increased too fast.
S2, introducing anhydrous hydrogen fluoride with a first batch of feeding amount into the reaction kettle in a water cooling state, slowly introducing liquid ammonia with the first batch of feeding amount into the reaction kettle, and controlling the flow of the liquid ammonia to ensure that the temperature of a reaction system does not exceed 95 ℃; specifically, the reaction system temperature should not exceed 90 ℃ when ammonium fluoride is produced, and the reaction system temperature should not exceed 95 ℃ when ammonium bifluoride is produced.
S3, after ammonia introduction is finished in S2, introducing anhydrous hydrogen fluoride with a second batch of material quantity into the reaction kettle, keeping the temperature of a reaction system not more than 95 ℃, introducing liquid ammonia with a second batch of material quantity into the reaction kettle, keeping the temperature of the reaction system not more than 95 ℃, and sequentially and alternately reacting; specifically, the reaction system temperature should not exceed 90 ℃ when ammonium fluoride is produced, and the reaction system temperature should not exceed 95 ℃ when ammonium bifluoride is produced.
S4, after the reaction of S3, sampling from the reaction liquid, monitoring the reaction end point by adopting a rapid acid-base titration method, and controlling the feeding amount of anhydrous hydrofluoric acid or liquid ammonia according to the monitoring result until the reaction is complete;
s5, pumping the completely reacted materials in the S4 reaction kettle to a circulating tank filled with mother liquor in advance, reducing the temperature of the materials to be below 80 ℃, and stirring and mixing;
s6, pumping the material in the circulating tank in the S5 to the top of the spray tower, enabling the material to fall from the top of the spray tower through a distributor to enable the material to be in contact with cold air from bottom to top in the spray tower, sequentially passing through two layers of demisters with opposite directions, re-entering the circulating tank from the bottom of the spray tower, and circularly cooling the material in such a way to enable the temperature of the material to be reduced to 35-45 ℃;
s7, pumping the cooled material in the S6 circulating tank to a crystal growing tank, and growing crystals;
s8, pumping the crystals cultured in the S7 crystal growing tank to a horizontal centrifuge, feeding the crystals into a packaging tank through a self-unloading material, and packaging to obtain a finished product of ammonium fluoride or ammonium bifluoride; specifically, the horizontal centrifuge adopts an automatic discharge centrifuge, and preferably adopts a hydrofluoric acid corrosion prevention measure or is made of a hydrofluoric acid corrosion resistant material.
S9, automatically flowing the mother liquor separated in the S8 to a solid-liquid separator, allowing the upper clear liquid to enter a mother liquor tank, combining the lower solid-liquid mixture with the liquid separated by the gas-liquid separator in the tail gas system, and then returning the mixture to a circulation tank;
and S10, combining tail gas of equipment facilities, sending the tail gas into a three-stage spray tower, and emptying after mother liquor absorption.
When the ammonium fluoride is produced, the method adopts a rapid acid-base titration method as follows: taking 2mL of reaction solution, putting the reaction solution into a colorimetric tube added with 50mL of water in advance, and dripping 2 drops of 1g/L bromocresol purple indicator solution to obtain sample solution; (1) when the sample liquid is purple, comparing with the standard liquid, if the purple of the sample liquid is deeper than the standard liquid, excessive ammonia is contained in the reaction system, and anhydrous hydrofluoric acid is not required to be supplemented, and if the purple of the sample liquid is lighter than the standard liquid, the reaction is complete; (2) when the sample liquid is yellow, titrating to purple with 1mol/L alkaline solution, and recording the consumed volume of the alkaline solution as V:
when V is more than 0.2mL, the ammonia in the reaction system is insufficient, and ammonia needs to be supplemented;
the reaction was complete when 0< V <0.2 ml.
Specifically, the standard solution is prepared by measuring 50mL of buffer solution with pH6.8, placing the buffer solution in a 50mL colorimetric tube, adding 2 drops of 1g/L bromocresol purple indicator solution, and shaking up.
Specifically, the alkaline solution may be a strong alkaline solution such as sodium hydroxide, potassium hydroxide, calcium hydroxide, and barium hydroxide, which are readily soluble in water.
Specifically, the detection mechanism of the rapid acid-base titration method is as follows: the color change pH range of the bromocresol purple indicator is from 5.2 (yellow) to 6.8 (violet), where the color change is gradually lighter in yellow; when the pH value is 5.7-5.8, the color is almost colorless, gradually changes to light blue along with the gradual increase of the pH value, and gradually deepens from the light blue to purple. Therefore, when the purple color of the sample liquid is darker than that of the standard liquid, the free ammonia in the system is excessive, and the liquid ammonia is excessive. When the indicator is added into the reaction solution to be yellow, titrating by using an alkaline solution to titrate weak acid salt as strong base, wherein the pH jump range is 0.2 percent around the stoichiometric point, and the pH value is 5.2-5.7 and can still be determined as the stoichiometric point; the reaction was complete when less than 0.2mL of sodium hydroxide was consumed by titration.
Specifically, during the detection control of the reaction end point, the sampling amount is automatically set according to the solid content in the reaction liquid, and the relatively more accurate area of the burette scale of the consumption volume of the alkaline solution every time is controlled. The alkaline concentration is not limited to 1mol/L, but the pH jump range is enlarged due to the increase of the concentration of the alkaline solution, so that the end point control is not facilitated; the concentration of the alkaline solution is reduced, the pH jump range is reduced, and according to the pH jump change rule of strong base titration weak acid salt, when the concentration is 0.1mol/L, the pH jump range is about 5.3-6.5, but the dosage of the titration solution is increased, and the detection time is increased. The end point judgment basis is not limited to 0.2-0mL, and the detection data of the reaction end point, the quality data of the finished product and the concentration of the titration solution are determined.
When the ammonium bifluoride is produced, the rapid acid-base titration method is adopted as follows: taking 2mL of reaction liquid, adding 50mL of water, dripping 2-3 drops of 10g/L phenolphthalein indicator liquid for the first time, titrating to light red by using 1mol/L alkaline solution, and recording the volume consumed by the alkaline solution as V1; adding 20mL of neutral formaldehyde solution for the second time, titrating the solution to light red by using 1mol/L alkaline solution, and recording the consumption volume of the alkaline solution as V2;
when the ratio (V1-V2) >0.5, the ammonia in the reaction system is insufficient, and ammonia needs to be supplemented;
when the reaction system is (V1-V2) <0, acid in the reaction system is insufficient, and anhydrous hydrofluoric acid is required to be supplemented;
when 0< (V1-V2) <0.5, the reaction was complete.
Specifically, the alkaline solution used may be a strong alkaline solution such as sodium hydroxide, potassium hydroxide, calcium hydroxide, and barium hydroxide that is easily soluble in water, but the alkaline solution used for the two titrations must be a solution prepared in the same batch for each detection.
Specifically, the detection mechanism of the rapid acid-base titration method is as follows:
first titration: NH (NH)4HF2+NaOH→NH4F+NaF+H2O
Second titration: 4NH4F+6HCHO→(CH2)6N4+4HF+6H2O
HF+NaOH→NaF+H2O
Specifically, the invention adopts a twice acid-base titration method to carry out reaction end point detection control, the sampling amount is automatically set according to the solid content in the reaction liquid, and the relatively more accurate scale region of the burette is controlled when the alkaline solution consumes the volume each time. The alkaline concentration is not limited to 1mol/L, but the pH jump range is enlarged when the concentration of the alkaline solution is increased, which is not beneficial to the end point control; the concentration of the alkaline solution is reduced, the dosage of the titration solution is increased, and the detection time is increased. The endpoint judgment basis is not limited to 0.5-0mL, and the reaction endpoint detection data, the finished product quality data and the concentration of the titration solution are determined in the early stage.
The distributor can be made of plastic or metal resistant to corrosion of hydrofluoric acid, can effectively prevent the distributor from being corroded by hydrofluoric acid and prolong the service life of the distributor, and particularly can be made of Hastelloy; the demister is a cyclone plate or a baffle plate.
In the crystal growing process, the crystal growth time is not more than 24 hours because the ammonium fluoride and the ammonium bifluoride crystals are easy to form walls; specifically, it may be 2h, 3h, 4h, 5h … … 23 h.
The horizontal centrifuge adopted in the invention adopts the automatic discharging centrifuge which is made of hydrofluoric acid corrosion prevention measures or hydrofluoric acid corrosion resistant materials, so that the production continuity can be ensured, the equipment is effectively prevented from being corroded, and the service life of the equipment is prolonged.
The whole production process of the invention is completed under the condition of closed micro negative pressure, and the production environment of a workshop can be greatly improved. Particularly, materials are conveyed through a pump and a pipeline in the production process, so that the labor intensity of workers can be reduced by about 75%; the tail gas in the production process is uniformly and intensively recycled and recycled, no waste liquid or waste residue is generated, and zero-emission production is basically achieved.
The present invention is described in further detail below with reference to examples:
example 1
A crystallization method of ammonium fluoride adopts an air-cooled spray cooling tower for crystallization, and specifically comprises the following steps:
s1, pumping 1t of ammonium fluoride mother liquor into a reaction kettle with a graphite tube array cooling tower, and dividing the amount of anhydrous hydrogen fluoride and the amount of liquid ammonia into 2 batches respectively according to theoretical feeding amount;
s2, introducing 270kg of anhydrous hydrogen fluoride with a first batch of feeding amount into the reaction kettle in a water cooling state, slowly introducing 233kg of liquid ammonia with the first batch of feeding amount into the reaction kettle, and controlling the flow of the liquid ammonia to ensure that the temperature of a reaction system does not exceed 85 ℃;
s3, after ammonia introduction of S2 is finished, introducing 270kg of anhydrous hydrogen fluoride with a second batch of material dosage into the reaction kettle, keeping the temperature of a reaction system not to exceed 85 ℃, introducing 232kg of liquid ammonia with a second batch of material dosage into the reaction kettle, and keeping the temperature of the reaction system not to exceed 85 ℃;
s4, after the reaction of S3 is finished, taking 2mL of reaction solution, adding 50mL of water and 2 drops of 1g/L bromocresol purple indicator solution, wherein the solution is purple and is lighter than the standard solution, and the reaction is complete;
s5, pumping the completely reacted materials in the S4 reaction kettle to a circulating tank filled with mother liquor in advance, reducing the temperature of the materials to be below 80 ℃, and stirring and mixing;
s6, pumping the material in the circulating tank in the S5 to the top of the spray tower, enabling the material to fall from the top of the spray tower through a distributor to enable the material to be in contact with cold air from bottom to top in the spray tower, sequentially passing through two layers of demisters with opposite directions, re-entering the circulating tank from the bottom of the spray tower, and circularly cooling the material in such a way to enable the temperature of the material to be reduced to 35 ℃;
s7, pumping the cooled material in the S6 circulating tank to a crystal growing tank, and culturing crystals for 2 hours;
s8, conveying the crystals cultured in the S7 crystal growing tank to a horizontal centrifuge for centrifugation, feeding the crystals into a packaging tank through self-unloading materials, packaging to obtain 994kg of ammonium fluoride crystals, and ensuring that the conversion rate of finished products reaches 98.91 percent
S9, automatically flowing the mother liquor separated in the S8 to a solid-liquid separator, allowing the upper clear liquid to enter a mother liquor tank, combining the lower solid-liquid mixture with the liquid separated by the gas-liquid separator in the tail gas system, and then returning the mixture to a circulation tank;
and S10, combining tail gas of equipment facilities, sending the tail gas into a three-stage spray tower, and emptying after mother liquor absorption.
Example 2
A crystallization method of ammonium bifluoride adopts an air-cooled spray cooling tower for crystallization, and specifically comprises the following steps:
s1, pumping 2t of ammonium bifluoride mother liquor into a reaction kettle with a graphite tube array cooling tower, and dividing the amount of anhydrous hydrogen fluoride and the amount of liquid ammonia into 3 batches respectively according to theoretical feeding amount;
s2, introducing 700kg of anhydrous hydrogen fluoride with a first batch of feeding amount into the reaction kettle in a water cooling state, then slowly introducing 299kg of liquid ammonia with the first batch of feeding amount into the reaction kettle, and controlling the flow of the liquid ammonia to ensure that the temperature of a reaction system does not exceed 93 ℃;
s3, after ammonia introduction of S2 is finished, introducing 700kg of anhydrous hydrogen fluoride with a second batch of material dosage into the reaction kettle, keeping the temperature of a reaction system not to exceed 93 ℃, introducing 298kg of liquid ammonia with a second batch of material dosage into the reaction kettle, and keeping the temperature of the reaction system not to exceed 93 ℃;
s4, after ammonia introduction of S3 is finished, introducing 700kg of anhydrous hydrogen fluoride with a third batch of material dosage into the reaction kettle, keeping the temperature of a reaction system not to exceed 93 ℃, introducing 298kg of liquid ammonia with a third batch of material dosage into the reaction kettle, and keeping the temperature of the reaction system not to exceed 93 ℃;
s5, after the reaction of S4 is completed, 2mL of reaction solution is taken, 50mL of water and 3 drops of 10g/L phenolphthalein indicator solution are added, 1mol/L sodium hydroxide solution is used for titration to light red, and 16.52mL of sodium hydroxide solution is consumed. Adding 20mL of neutral formaldehyde solution into the titration solution, fading the light red color, titrating the titration solution again to the light red color by using 1mol/L of sodium hydroxide solution, consuming 16.26mL of the sodium hydroxide solution, (V1-V2) ═ 0.26mL, and completely reacting;
s6, pumping the completely reacted materials in the S5 reaction kettle to a circulating tank filled with mother liquor in advance, reducing the temperature of the materials to be below 80 ℃, and stirring and mixing;
s7, pumping the material in the circulating tank in the S6 to the top of the spray tower, enabling the material to fall from the top of the spray tower through a distributor to enable the material to be in contact with cold air from bottom to top in the spray tower, sequentially passing through two layers of demisters with opposite directions, re-entering the circulating tank from the bottom of the spray tower, and circularly cooling the material in such a way to enable the temperature of the material to be reduced to 42 ℃;
s8, pumping the cooled material in the S7 circulating tank to a crystal growing tank, and culturing crystals for 2 hours;
s9, conveying the crystals cultured in the S8 crystal growing tank to a horizontal centrifuge for centrifugation, feeding the crystals into a packaging tank through self-unloading materials, and packaging to obtain 2990kg of ammonium bifluoride crystals, wherein the conversion rate of finished products is as high as 99.83%.
S10, automatically flowing the mother liquor separated in the S9 to a solid-liquid separator, allowing the upper clear liquid to enter a mother liquor tank, combining the lower solid-liquid mixture with the liquid separated by the gas-liquid separator in the tail gas system, and then returning the mixture to a circulation tank;
and S11, combining tail gas of equipment facilities, sending the tail gas into a three-stage spray tower, and emptying after mother liquor absorption.
Detection and analysis: the quality of the ammonium fluoride produced in example 1 is detected according to the detection method in GB/T28653-2012 standard, and the result is shown in Table 1; the quality of the ammonium bifluoride produced in example 2 was determined according to the detection method in GB/T28655 and 2012, and the results are shown in Table 2.
TABLE 1 ammonium fluoride test results
Item | Example 1 | First-class article in GB/T28653- |
Ammonium fluoride w/%) | 95.42 | ≥95.0 |
Free acid (as HF) w/%) | 0 | ≤1.0 |
Fluosilicic acid [ in (NH)4)2SiF6Meter]w/% | 0.34 | ≤0.5 |
As can be seen from the results in Table 1, the ammonium fluoride produced by the preparation method of the invention has excellent quality, and meets the requirements of first-class products in GB/T28653-.
TABLE 2 ammonium bifluoride assay results
As can be seen from the results in Table 2, the quality of the ammonium bifluoride produced by the preparation method of the invention is excellent, and meets the requirements of first-class products in GB/T28655-2012.
In conclusion, the crystallization method of ammonium fluoride or ammonium bifluoride provided by the invention adopts the air-cooled spray cooling tower for crystallization, the cooling speed is high, the operation of the whole production process is simple and easy to control, the reaction end point can be accurately controlled, the obtained product crystal particles are uniform, compact and stable, the yield of the finished product is high, and the requirements of first-class products in national standards are met; meanwhile, liquid and tail gas in the production process are uniformly and intensively recovered and recycled, no waste liquid or waste residue is generated, and zero-emission production is basically achieved.
Finally, it should be emphasized that the above-described preferred embodiments of the present invention are merely examples of implementations, rather than limitations, and that many variations and modifications of the invention are possible to those skilled in the art, without departing from the spirit and scope of the invention.
Claims (10)
1. A crystallization method of ammonium fluoride or ammonium bifluoride is characterized in that the crystallization method adopts an air-cooled spray cooling tower for crystallization, and specifically comprises the following steps:
s1, pumping mother liquor or water into a reaction kettle with a graphite tube array cooling tower, and dividing the amount of anhydrous hydrogen fluoride and the amount of liquid ammonia into a plurality of batches respectively according to theoretical feeding amount;
s2, introducing anhydrous hydrogen fluoride with a first batch of feeding amount into the reaction kettle in a water cooling state, slowly introducing liquid ammonia with the first batch of feeding amount into the reaction kettle, and controlling the flow of the liquid ammonia to ensure that the temperature of a reaction system does not exceed 95 ℃;
s3, after ammonia introduction is finished in S2, introducing anhydrous hydrogen fluoride with a second batch of material quantity into the reaction kettle, keeping the temperature of a reaction system not more than 95 ℃, introducing liquid ammonia with a second batch of material quantity into the reaction kettle, keeping the temperature of the reaction system not more than 95 ℃, and sequentially and alternately reacting;
s4, after the reaction of S3, sampling from the reaction liquid, monitoring the reaction end point by adopting a rapid acid-base titration method, and controlling the feeding amount of anhydrous hydrofluoric acid or liquid ammonia according to the monitoring result until the reaction is complete;
s5, pumping the completely reacted materials in the S4 reaction kettle to a circulating tank filled with mother liquor in advance, reducing the temperature of the materials to be below 80 ℃, and stirring and mixing;
s6, pumping the material in the circulating tank in the S5 to the top of the spray tower, enabling the material to fall from the top of the spray tower through a distributor to enable the material to be in contact with cold air from bottom to top in the spray tower, sequentially passing through two layers of demisters with opposite directions, re-entering the circulating tank from the bottom of the spray tower, and circularly cooling the material in such a way to enable the temperature of the material to be reduced to 35-45 ℃;
s7, feeding the cooled material in the S6 circulating tank to a crystal growing tank to grow crystals;
s8, pumping the crystals cultured in the S7 crystal growing tank to a horizontal centrifuge, feeding the crystals into a packaging tank through a self-unloading material, and packaging to obtain a packaged finished product;
s9, automatically flowing the mother liquor separated in the S8 to a solid-liquid separator, allowing the upper clear liquid to enter a mother liquor tank, combining the lower solid-liquid mixture with the liquid separated by the gas-liquid separator in the tail gas system, and then returning the mixture to a circulation tank;
and S10, combining tail gas of equipment facilities, sending the tail gas into a three-stage spray tower, and emptying after mother liquor absorption.
2. The method for crystallizing ammonium fluoride or ammonium bifluoride according to claim 1, wherein the anhydrous hydrogen fluoride and the liquid ammonia are divided into 2 to 5 batches in S1, respectively.
3. The crystallization method of ammonium fluoride or ammonium bifluoride according to claim 1, wherein, in the production of ammonium fluoride in S4, the rapid acid-base titration method is: taking 2mL of reaction solution, putting the reaction solution into a colorimetric tube added with 50mL of water in advance, and dripping 2 drops of 1g/L bromocresol purple indicator solution to obtain sample solution; (1) when the sample liquid is purple, comparing with the standard liquid, if the purple of the sample liquid is deeper than the standard liquid, excessive ammonia is contained in the reaction system, and anhydrous hydrofluoric acid is not required to be supplemented, and if the purple of the sample liquid is lighter than the standard liquid, the reaction is complete; (2) when the sample liquid is yellow, titrating to purple with 1mol/L alkaline solution, and recording the consumed volume of the alkaline solution as V:
when V is more than 0.2mL, the ammonia in the reaction system is insufficient, and ammonia needs to be supplemented;
the reaction was complete when 0< V <0.2 ml.
4. The method for crystallizing ammonium fluoride or ammonium bifluoride according to claim 3, wherein the standard solution is prepared by measuring 50mL of a pH6.8 buffer solution, placing the buffer solution in a 50mL colorimetric tube, adding 2 drops of 1g/L bromocresol purple indicator solution, and shaking up.
5. The crystallization method of ammonium fluoride or ammonium bifluoride according to claim 1, wherein, in the production of ammonium bifluoride in S4, the rapid acid-base titration method is: taking 2mL of reaction liquid, adding 50mL of water, dripping 2-3 drops of 10g/L phenolphthalein indicator liquid for the first time, titrating to light red by using 1mol/L alkaline solution, and recording the volume consumed by the alkaline solution as V1; adding 20mL of neutral formaldehyde solution for the second time, titrating the solution to light red by using 1mol/L alkaline solution, and recording the consumption volume of the alkaline solution as V2;
when the ratio (V1-V2) >0.5, the ammonia in the reaction system is insufficient, and ammonia needs to be supplemented;
when the (V1-V2) <0, the acid in the reaction system is insufficient, and hydrofluoric acid needs to be supplemented;
when 0< (V1-V2) <0.5, the reaction was complete.
6. The method for crystallizing ammonium fluoride or ammonium bifluoride according to claim 3 or 5, wherein the alkaline solution is any one of sodium hydroxide, potassium hydroxide, calcium hydroxide and barium hydroxide.
7. The method according to claim 1, wherein the distributor is made of plastic or metal resistant to corrosion by hydrofluoric acid in S6; the demister is a cyclone plate or a baffle plate.
8. The method for crystallizing ammonium fluoride or ammonium bifluoride as claimed in claim 1, wherein said time for growing crystals in S7 is not more than 24 hours.
9. The method for crystallizing ammonium fluoride or ammonium bifluoride as claimed in claim 1, wherein in S8, the horizontal centrifuge is an automatic discharge centrifuge made of a material having hydrofluoric acid corrosion resistance or a hydrofluoric acid corrosion resistance.
10. The crystallization method of ammonium fluoride or ammonium bifluoride according to claim 1, wherein the crystallization method is performed under a closed micro-negative pressure condition.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202110801403.6A CN113479907B (en) | 2021-07-15 | 2021-07-15 | Crystallization method of ammonium fluoride or ammonium bifluoride |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202110801403.6A CN113479907B (en) | 2021-07-15 | 2021-07-15 | Crystallization method of ammonium fluoride or ammonium bifluoride |
Publications (2)
Publication Number | Publication Date |
---|---|
CN113479907A true CN113479907A (en) | 2021-10-08 |
CN113479907B CN113479907B (en) | 2022-10-18 |
Family
ID=77939547
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202110801403.6A Active CN113479907B (en) | 2021-07-15 | 2021-07-15 | Crystallization method of ammonium fluoride or ammonium bifluoride |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN113479907B (en) |
Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
ES225344A1 (en) * | 1954-12-31 | 1956-02-01 | Int Minerals & Chem Corp | Process for the preparation of ammonium fluoride |
DE1189057B (en) * | 1961-07-17 | 1965-03-18 | Grace W R & Co | Process for the production of ammonium hydrogen fluoride |
US4026997A (en) * | 1973-09-21 | 1977-05-31 | Bayer Aktiengesellschaft | Process for the production of ammonium fluoride from fluosilicic acid |
CN1385369A (en) * | 2002-01-15 | 2002-12-18 | 姜仁和 | Proces for direct synthesizing fluoammonium salt |
CN101269816A (en) * | 2008-05-16 | 2008-09-24 | 夏克立 | Method for producing fluorine series compounds and white carbon black |
CN102689876A (en) * | 2011-03-25 | 2012-09-26 | 精工爱普生株式会社 | Separating method and separating apparatus |
CN103303941A (en) * | 2013-05-30 | 2013-09-18 | 福建省邵武市永飞化工有限公司 | Preparation method of ammonium fluoride |
CN103803584A (en) * | 2012-11-08 | 2014-05-21 | 福建省邵武市永飞化工有限公司 | Ammonium bifluoride preparation method |
CN106145160A (en) * | 2015-04-03 | 2016-11-23 | 东至天孚化工有限公司 | A kind of ammonium acid fluoride production method |
CN106608646A (en) * | 2015-11-22 | 2017-05-03 | 宁夏际华环境安全科技有限公司 | Production process for ammonium fluoride |
CN107540001A (en) * | 2016-06-29 | 2018-01-05 | 宁夏海诚电化信息科技有限公司 | A kind of ammonium acid fluoride production technology |
CN107879360A (en) * | 2017-12-19 | 2018-04-06 | 浙江朗泰环境工程有限公司 | A kind of ammonium acid fluoride mother liquor cooling system |
CN108910916A (en) * | 2018-08-20 | 2018-11-30 | 福建永晶科技股份有限公司 | A kind of preparation method and its preparation system of ammonium acid fluoride |
-
2021
- 2021-07-15 CN CN202110801403.6A patent/CN113479907B/en active Active
Patent Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
ES225344A1 (en) * | 1954-12-31 | 1956-02-01 | Int Minerals & Chem Corp | Process for the preparation of ammonium fluoride |
DE1189057B (en) * | 1961-07-17 | 1965-03-18 | Grace W R & Co | Process for the production of ammonium hydrogen fluoride |
US4026997A (en) * | 1973-09-21 | 1977-05-31 | Bayer Aktiengesellschaft | Process for the production of ammonium fluoride from fluosilicic acid |
CN1385369A (en) * | 2002-01-15 | 2002-12-18 | 姜仁和 | Proces for direct synthesizing fluoammonium salt |
CN101269816A (en) * | 2008-05-16 | 2008-09-24 | 夏克立 | Method for producing fluorine series compounds and white carbon black |
CN102689876A (en) * | 2011-03-25 | 2012-09-26 | 精工爱普生株式会社 | Separating method and separating apparatus |
CN103803584A (en) * | 2012-11-08 | 2014-05-21 | 福建省邵武市永飞化工有限公司 | Ammonium bifluoride preparation method |
CN103303941A (en) * | 2013-05-30 | 2013-09-18 | 福建省邵武市永飞化工有限公司 | Preparation method of ammonium fluoride |
CN106145160A (en) * | 2015-04-03 | 2016-11-23 | 东至天孚化工有限公司 | A kind of ammonium acid fluoride production method |
CN106608646A (en) * | 2015-11-22 | 2017-05-03 | 宁夏际华环境安全科技有限公司 | Production process for ammonium fluoride |
CN107540001A (en) * | 2016-06-29 | 2018-01-05 | 宁夏海诚电化信息科技有限公司 | A kind of ammonium acid fluoride production technology |
CN107879360A (en) * | 2017-12-19 | 2018-04-06 | 浙江朗泰环境工程有限公司 | A kind of ammonium acid fluoride mother liquor cooling system |
CN108910916A (en) * | 2018-08-20 | 2018-11-30 | 福建永晶科技股份有限公司 | A kind of preparation method and its preparation system of ammonium acid fluoride |
Non-Patent Citations (2)
Title |
---|
俞松林: "《药物分析》", 31 July 2008 * |
黄忠等: "高杂质氟硅酸制备氟化铵联产氟化镁工艺技术研究", 《无机盐工业》 * |
Also Published As
Publication number | Publication date |
---|---|
CN113479907B (en) | 2022-10-18 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN101898769B (en) | Method for producing high-purity ammonium bifluoride | |
CN101973552A (en) | Method for separating silicon from impurities | |
CN105502451B (en) | A kind of method for producing aluminum fluoride coproduction cryolite with high molecular ratio | |
CN107963617A (en) | The production method and system of a kind of nitrosyl sulfuric acid | |
CN103071365A (en) | Treatment method for tail gas produced by reaction of sulfonyl chlorination | |
CN106861582B (en) | The purification and hydrodynamics fused salt tank of high-temperature liquid state nitrate | |
CN113479907B (en) | Crystallization method of ammonium fluoride or ammonium bifluoride | |
CN108163812A (en) | A kind of preparation method of hydrogen fluoride, the preparation method of hydrofluoric acid | |
CN114455548A (en) | Method for continuously producing peroxysulfuric acid | |
CN110316749A (en) | A kind of method of fluosilicic acid direct method production aluminum fluoride | |
CN113479908B (en) | Preparation method of ammonium fluoride or ammonium bifluoride | |
CN103303946A (en) | Sodium bicarbonate crystal preparation equipment and process for preparing sodium bicarbonate crystals by utilizing same | |
CN101134579A (en) | Method for producing ammonium bisulfate and hydrogen chloride by using ammonium chloride and sulfuric acid | |
CN111320544A (en) | Process and equipment for three-stage semi-continuous synthesis of bis (trichloromethyl) carbonate | |
CN217808770U (en) | System for anhydrous hydrogen fluoride is prepared to fluosilicic acid | |
CN108002392B (en) | The method for preparing ammonium fluosilicate co-producing white carbon black using phosphoric acid plant fluorinated tail gas | |
CN114988376B (en) | Lithium amide production method | |
CN101092236A (en) | Method for preparing salt of hydroxylamine by using 'coupling' technique of reactive extraction | |
CN113845093B (en) | Method for continuously preparing peroxymonosulfuric acid by utilizing microchannel reactor | |
CN214167372U (en) | System for preparing stannous chloride by recycling dilute hydrochloric acid tail gas | |
CN219469708U (en) | Equipment for preparing electrolyte for nitrogen trifluoride | |
CN107879360B (en) | Ammonium bifluoride mother liquor cooling system | |
CN206051577U (en) | A kind of ammonium acid fluoride Moist chemical synthesis system | |
CN106587494A (en) | Method for improving ammonia-nitrogen content of H acid wastewater | |
CN209322482U (en) | Salting-out crystallization Outer Cooler liquefied ammonia cooling device in procedure of producing soda under joint alkaline process |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant | ||
EE01 | Entry into force of recordation of patent licensing contract | ||
EE01 | Entry into force of recordation of patent licensing contract |
Application publication date: 20211008 Assignee: Jiangxi Sanjia Fluorochemical Co.,Ltd. Assignor: JIANGXI DONGYAN PHARMACEUTICAL Co.,Ltd. Contract record no.: X2024980012407 Denomination of invention: A crystallization method of ammonium fluoride or ammonium hydrogen fluoride Granted publication date: 20221018 License type: Common License Record date: 20240819 |