CN114016061B - Method and device for preparing octafluoropropane through electrolysis - Google Patents
Method and device for preparing octafluoropropane through electrolysis Download PDFInfo
- Publication number
- CN114016061B CN114016061B CN202111276208.2A CN202111276208A CN114016061B CN 114016061 B CN114016061 B CN 114016061B CN 202111276208 A CN202111276208 A CN 202111276208A CN 114016061 B CN114016061 B CN 114016061B
- Authority
- CN
- China
- Prior art keywords
- octafluoropropane
- electrolytic
- cooling
- electrolysis
- collecting
- 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.)
- Active
Links
- QYSGYZVSCZSLHT-UHFFFAOYSA-N octafluoropropane Chemical compound FC(F)(F)C(F)(F)C(F)(F)F QYSGYZVSCZSLHT-UHFFFAOYSA-N 0.000 title claims abstract description 92
- 229960004065 perflutren Drugs 0.000 title claims abstract description 92
- 238000005868 electrolysis reaction Methods 0.000 title claims abstract description 49
- 238000000034 method Methods 0.000 title claims abstract description 35
- 238000001816 cooling Methods 0.000 claims abstract description 65
- 239000002994 raw material Substances 0.000 claims abstract description 41
- 239000000047 product Substances 0.000 claims abstract description 33
- 239000003792 electrolyte Substances 0.000 claims abstract description 32
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 25
- 238000010438 heat treatment Methods 0.000 claims abstract description 22
- 239000012043 crude product Substances 0.000 claims abstract description 17
- 239000007791 liquid phase Substances 0.000 claims abstract description 16
- 150000003839 salts Chemical class 0.000 claims abstract description 11
- 229910001515 alkali metal fluoride Inorganic materials 0.000 claims abstract description 10
- 238000002360 preparation method Methods 0.000 claims abstract description 9
- 238000002156 mixing Methods 0.000 claims abstract description 4
- 239000007789 gas Substances 0.000 claims description 35
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 25
- 230000007246 mechanism Effects 0.000 claims description 23
- 229910052759 nickel Inorganic materials 0.000 claims description 12
- 230000008569 process Effects 0.000 claims description 11
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 10
- 239000012071 phase Substances 0.000 claims description 10
- FERIUCNNQQJTOY-UHFFFAOYSA-N Butyric acid Chemical compound CCCC(O)=O FERIUCNNQQJTOY-UHFFFAOYSA-N 0.000 claims description 7
- 239000000110 cooling liquid Substances 0.000 claims description 7
- 239000007788 liquid Substances 0.000 claims description 7
- LSACYLWPPQLVSM-UHFFFAOYSA-N isobutyric acid anhydride Chemical compound CC(C)C(=O)OC(=O)C(C)C LSACYLWPPQLVSM-UHFFFAOYSA-N 0.000 claims description 6
- 229910052751 metal Inorganic materials 0.000 claims description 6
- 239000002184 metal Substances 0.000 claims description 6
- YHASWHZGWUONAO-UHFFFAOYSA-N butanoyl butanoate Chemical compound CCCC(=O)OC(=O)CCC YHASWHZGWUONAO-UHFFFAOYSA-N 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 229910052757 nitrogen Inorganic materials 0.000 claims description 5
- FERIUCNNQQJTOY-UHFFFAOYSA-M Butyrate Chemical compound CCCC([O-])=O FERIUCNNQQJTOY-UHFFFAOYSA-M 0.000 claims description 3
- RWMKSKOZLCXHOK-UHFFFAOYSA-M potassium;butanoate Chemical group [K+].CCCC([O-])=O RWMKSKOZLCXHOK-UHFFFAOYSA-M 0.000 claims description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 2
- MFBOGIVSZKQAPD-UHFFFAOYSA-M sodium butyrate Chemical compound [Na+].CCCC([O-])=O MFBOGIVSZKQAPD-UHFFFAOYSA-M 0.000 claims description 2
- 238000003889 chemical engineering Methods 0.000 abstract description 2
- 239000012847 fine chemical Substances 0.000 abstract description 2
- 238000006243 chemical reaction Methods 0.000 description 13
- 238000003682 fluorination reaction Methods 0.000 description 8
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 description 6
- WZJQNLGQTOCWDS-UHFFFAOYSA-K cobalt(iii) fluoride Chemical compound F[Co](F)F WZJQNLGQTOCWDS-UHFFFAOYSA-K 0.000 description 6
- 229910021583 Cobalt(III) fluoride Inorganic materials 0.000 description 5
- HCDGVLDPFQMKDK-UHFFFAOYSA-N hexafluoropropylene Chemical group FC(F)=C(F)C(F)(F)F HCDGVLDPFQMKDK-UHFFFAOYSA-N 0.000 description 5
- 239000012535 impurity Substances 0.000 description 4
- 150000003254 radicals Chemical class 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- UKACHOXRXFQJFN-UHFFFAOYSA-N heptafluoropropane Chemical compound FC(F)C(F)(F)C(F)(F)F UKACHOXRXFQJFN-UHFFFAOYSA-N 0.000 description 3
- 239000001294 propane Substances 0.000 description 3
- 239000002699 waste material Substances 0.000 description 3
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 description 2
- 239000003513 alkali Substances 0.000 description 2
- 239000003054 catalyst Substances 0.000 description 2
- KYKAJFCTULSVSH-UHFFFAOYSA-N chloro(fluoro)methane Chemical compound F[C]Cl KYKAJFCTULSVSH-UHFFFAOYSA-N 0.000 description 2
- 238000004880 explosion Methods 0.000 description 2
- 229930195733 hydrocarbon Natural products 0.000 description 2
- 150000002430 hydrocarbons Chemical class 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 238000000746 purification Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical group [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910021582 Cobalt(II) fluoride Inorganic materials 0.000 description 1
- 241001391944 Commicarpus scandens Species 0.000 description 1
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 150000004648 butanoic acid derivatives Chemical class 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- YCYBZKSMUPTWEE-UHFFFAOYSA-L cobalt(ii) fluoride Chemical compound F[Co]F YCYBZKSMUPTWEE-UHFFFAOYSA-L 0.000 description 1
- 239000006258 conductive agent Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000000539 dimer Substances 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- WMIYKQLTONQJES-UHFFFAOYSA-N hexafluoroethane Chemical compound FC(F)(F)C(F)(F)F WMIYKQLTONQJES-UHFFFAOYSA-N 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000002085 irritant Substances 0.000 description 1
- 231100000021 irritant Toxicity 0.000 description 1
- 239000002973 irritant agent Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000004377 microelectronic Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- QQONPFPTGQHPMA-UHFFFAOYSA-N propylene Natural products CC=C QQONPFPTGQHPMA-UHFFFAOYSA-N 0.000 description 1
- 125000004805 propylene group Chemical group [H]C([H])([H])C([H])([*:1])C([H])([H])[*:2] 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- TXEYQDLBPFQVAA-UHFFFAOYSA-N tetrafluoromethane Chemical compound FC(F)(F)F TXEYQDLBPFQVAA-UHFFFAOYSA-N 0.000 description 1
- 238000007039 two-step reaction Methods 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B3/00—Electrolytic production of organic compounds
- C25B3/01—Products
- C25B3/11—Halogen containing compounds
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B3/00—Electrolytic production of organic compounds
- C25B3/20—Processes
- C25B3/27—Halogenation
- C25B3/28—Fluorination
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B9/00—Cells or assemblies of cells; Constructional parts of cells; Assemblies of constructional parts, e.g. electrode-diaphragm assemblies; Process-related cell features
- C25B9/09—Fused bath cells
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B9/00—Cells or assemblies of cells; Constructional parts of cells; Assemblies of constructional parts, e.g. electrode-diaphragm assemblies; Process-related cell features
- C25B9/17—Cells comprising dimensionally-stable non-movable electrodes; Assemblies of constructional parts thereof
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B9/00—Cells or assemblies of cells; Constructional parts of cells; Assemblies of constructional parts, e.g. electrode-diaphragm assemblies; Process-related cell features
- C25B9/60—Constructional parts of cells
- C25B9/67—Heating or cooling means
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/10—Process efficiency
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)
Abstract
The invention relates to a method for preparing octafluoropropane by electrolysis, belonging to the technical field of fine chemical engineering. Firstly, mixing HF and alkali metal fluoride to obtain molten salt electrolyte, and adding the molten salt electrolyte into an electrolytic tank to electrolyze and remove water; then adding the raw materials into an electrolytic tank, controlling the electrolysis voltage to be 4-10V, controlling the electrolysis temperature to be-10-20 ℃, and collecting the electrolysis product to obtain a crude octafluoropropane product when the octafluoropropane is detected to be contained in the electrolysis product; then cooling the octafluoropropane crude product at the temperature of-70 ℃ to-50 ℃ and collecting a liquid phase; finally, heating and gasifying the liquid phase to obtain the octafluoropropane. The method can realize the preparation of octafluoropropane with high yield and high purity.
Description
Technical Field
The invention relates to a method and a device for preparing octafluoropropane by electrolysis, belonging to the technical field of fine chemical engineering.
Background
Octafluoropropane (C) 3 F 8 ) The method is widely applied to industries such as electronics, microelectronics, medicines and the like. At present, the preparation method of octafluoropropane basically adopts a chemical synthesis method, and the main approaches are as follows:
1. direct fluorination, wherein the main raw materials are hydrocarbons, hexafluoropropylene and fluorochloroalkanes; the main reactions are as follows: reaction of fluorochloroalkanes with HF: CClF (CClF) 2 CF 2 CF 3 +HF→C 3 F 8 +hcl; propane and F 2 The reaction: c (C) 3 H 8 +8F 2 →C 3 F 8 +8hf; hexafluoropropylene and F 2 The reaction: CF (compact flash) 3 CF＝CF 2 +F 2 →C 3 F 8 . The direct fluorination method is difficult to industrialize, mainly because of the following: (1) Hydrocarbons, hexafluoropropylene and F 2 The reaction can generate C-C bond rupture, and can generate by-products such as dimers, polymers and the like, so that the yield of the octafluoropropane is not high; (2) The fluorination of fluorochloroalkanes has the problem that unreacted fluorochloroalkanes are difficult to remove in the purification section.
2. Hexafluoropropylene is subjected to two-step reaction to obtain octafluoropropane; the main reactions are as follows: in the first step, in the presence of a fluorination catalyst, heptafluoropropane is first produced: CF (compact flash) 3 CF＝CF 2 +HF→CF 3 CHFCF 3 The method comprises the steps of carrying out a first treatment on the surface of the Second, heptafluoropropane is directly fluorinated: CF (compact flash) 3 CHFCF 3 +8F 2 →C 3 F 8 +hf. The method has the advantages of higher yield of the octafluoropropane, but the process flow is complex, and the first-step reaction has high requirements on equipment materials and catalysts.
3. Cobalt trifluoride (CoF) 3 ) The catalytic method mainly comprises the following steps: in the first step, hexafluoropropylene is fluorinated: CF (compact flash) 3 CF＝CF 2 +2CoF 3 →C 3 F 8 +2CoF 2 The method comprises the steps of carrying out a first treatment on the surface of the And a second step of: cobalt difluoride fluoride to cobalt trifluoride: 2CoF 2 +F 2 →2CoF 3 . The method has the advantage of higher yield of the octafluoropropane, but the process flow belongs to a batch preparation process, the production time efficiency is lower, cobalt trifluoride and cobalt difluoride are continuously converted, and the cobalt trifluoride is pulverized, so that the yield of the octafluoropropane is influenced.
4. The method comprises the steps of dispersing a gas raw material such as heptafluoropropane, propane or propylene in anhydrous HF for electrolysis, converting F element in the HF into F free radical on the surface of an anode, and reacting the F free radical with the gas raw material to generate anode gas containing octafluoropropane; at the same time, on the surface of the cathode, H element in HF is converted into H free radical, and the H free radical is combined to form hydrogen. The method has the advantages of simple process, stable anode product components and the like, but the electrolysis process has the problems that carbon chains are easy to break, impurities such as carbon tetrafluoride, hexafluoroethane and the like are easy to generate, and the yield of octafluoropropane is low.
Disclosure of Invention
In view of the above, the present invention aims to provide a method and an apparatus for preparing octafluoropropane by electrolysis.
In order to achieve the above purpose, the technical scheme of the invention is as follows:
a method for preparing octafluoropropane by electrolysis, comprising the following steps:
(1) Mixing HF and alkali metal fluoride at 0-10 deg.c to obtain molten salt electrolyte;
(2) Introducing the electrolyte into an electrolytic tank, electrolyzing to remove water, and emptying electrolytic gas;
(3) After the electrolytic water removal is finished, adding the raw materials into an electrolytic tank, controlling the electrolytic voltage to be 4-10V, controlling the electrolytic temperature to be-10-20 ℃, and collecting an electrolytic product to obtain an octafluoropropane crude product when the octafluoropropane is detected to be contained in the electrolytic product; the raw materials are isobutyric anhydride, butyric anhydride or butyric acid metal salt;
(4) Cooling the octafluoropropane crude product at the temperature of-70 ℃ to-50 ℃ and collecting a liquid phase;
(5) Heating and gasifying the liquid phase to obtain octafluoropropane;
wherein, the mass fraction of the alkali metal fluoride is 3-15%, the mass fraction of the raw material is 5-15% and the rest is HF, based on 100% of the total mass of the HF, the alkali metal fluoride and the raw material.
In step (1): preferably, the alkali metal fluoride is one or more of CsF, liF, KF and NaF.
In the step (2):
preferably, when the electrolytic water is removed, the electrolytic voltage is controlled to be 3-4V, the trend of the electrolytic current is observed, the voltage is increased to be 5-6V when the current is reduced to 0, and the electrolytic water removal is finished when the current is reduced to 0.
Preferably, the voltage is raised by 0.4V to 0.6V each time.
In the step (3):
preferably, the metal butyrate is potassium butyrate or sodium butyrate.
Preferably, the electrolysis voltage is 5V to 8V.
In the step (4):
preferably, the cooling temperature is-65 ℃ to-55 ℃.
Preferably, liquid nitrogen or liquid ammonia is used for cooling.
An apparatus for preparing octafluoropropane by electrolysis comprises an electrolytic tank and a cooling and collecting mechanism; the electrolytic tank is provided with an electrolyte inlet, a raw material inlet, an emptying port and a crude product collecting port, and the cooling mechanism is used for collecting the crude octafluoropropane discharged from the crude product collecting port, liquefying the octafluoropropane and heating and gasifying the liquefied octafluoropropane.
Further, the cooling collection mechanism comprises a cooling kettle, a cooling column and a heating unit, wherein the top of the cooling kettle is provided with a gas phase outlet and a product outlet; the bottom of the cooling column is communicated with the gas phase outlet, and the top of the cooling column is provided with a cooling column vent; and cooling liquid pipelines are arranged in the cooling kettle and the cooling column, and the heating unit is used for heating the cooling kettle.
Further, the porous anode and the porous cathode are porous nickel pipes or porous nickel plates.
Further, the distance between the porous anode and the porous cathode is 2mm to 20mm, preferably 3mm to 15mm.
Advantageous effects
The invention provides a method for preparing octafluoropropane by electrolysis, which takes isobutyric anhydride, butyric anhydride or metal butyrate as raw materials, takes mixed molten salt of HF and alkali metal fluoride as electrolyte, and obtains octafluoropropane crude product by electrolytic fluorination of the raw materials by controlling the pressure and temperature of electrolysis. Wherein, the electrolytic fluorination of the isobutyric anhydride has the reaction formula: CH (CH) 3 CH 3 CHCO-O-CH 3 CH 3 CHCO+HF→C 3 F 8 +CO 2 +H 2 The method comprises the steps of carrying out a first treatment on the surface of the The reaction formula of the electrolytic fluorination of butyric anhydride is: CH (CH) 3 CH 2 CH 2 CO-O-CH 3 CH 2 CH 2 CO+HF→C 3 F 8 +CO 2 +H 2 The method comprises the steps of carrying out a first treatment on the surface of the The reaction formula of the electrolytic fluorination of the metal butyrate salt is as follows: CH (CH) 3 CH 2 CH 2 COOM+HF→C 3 F 8 +CO 2 +H 2 +mf. Compared with an electrolytic system of liquid phase reaction raw materials, the reaction system is more stable and is easy to control. Due to the presence of H in the electrolytic gas 2 To prevent H 2 Accumulation in the subsequent purification process brings potential explosion risks; by C 3 F 8 And H is 2 And (3) cooling the crude octafluoropropane product to realize gas-liquid separation, and finally, further heating and gasifying the obtained liquefied octafluoropropane.
Drawings
FIG. 1 is a schematic diagram of an apparatus for preparing octafluoropropane by electrolysis according to the present invention.
Wherein, 1-electrolysis bath, 2-electrolyte inlet, 3-raw material inlet, 4-porous anode, 5-porous cathode, 6-vent, 7-crude product collection port, 8-cooling kettle, 9-cooling column, 10-cooling column vent, 11-cooling liquid pipeline, 12-product outlet.
Detailed Description
The present invention will be described in further detail with reference to specific examples.
As shown in fig. 1, an apparatus for producing octafluoropropane by electrolysis comprises an electrolytic tank 1, a cooling mechanism and a collecting mechanism 13; the electrolytic tank 1 is relatively provided with a plurality of groups of porous anodes 4 and porous cathodes 5, the electrolytic tank 1 is provided with an electrolyte inlet 2, a raw material inlet 3, an emptying port 6 and a crude product collecting port 7, and the cooling mechanism is used for collecting the crude octafluoropropane discharged from the crude product collecting port and liquefying octafluoropropane; the collecting means 13 is for collecting liquefied octafluoropropane and heating and gasifying the liquefied octafluoropropane.
The cooling collection mechanism comprises a cooling kettle 8, a cooling column 9 and a heating unit, wherein a gas phase outlet and a product outlet 12 are formed in the top of the cooling kettle 8; the bottom of the cooling column 9 is communicated with a gas phase outlet, and a cooling column vent 10 is formed in the top of the cooling column 9; the cooling kettle 8 and the cooling column 9 are respectively provided with a cooling liquid pipeline 11, and the heating unit is used for heating the cooling kettle 8.
The porous anode 4 and the porous cathode 5 are porous nickel pipes or porous nickel plates.
The spacing between each set of the porous anode and the porous cathode is 2mm to 20mm, preferably 3mm to 15mm. The electrode spacing is too small, firstly, when the electrode height is more than or equal to 500mm, the electrode contact can be caused by the assembly angle error of more than or equal to 1%, and the operation can not be performed; secondly, the space between the electrodes is narrow, most of the space is easily occupied by gas, firstly, the electrolytic current is low, secondly, the phenomenon that local high-temperature electrolyte cannot exchange heat in time can be caused, and the nickel anode is corroded to form NiF 2 Substances such as; when NiF 2 And the electrolyte is separated out from the cathode, which can lead to electrode short circuit and explosion of the electrolytic tank. The electrode spacing is too large, firstly, the electrode area of the unit volume of the electrolytic cell is too small, and the processing cost of the electrolytic cell is increased; and secondly, the electrolysis current is too low.
The electrolyzer mainly provides a closed electrolytic environment and stores electrolyte.
The porous anode mainly aims at providing a gas raw material channel and fluorine element for reaction.
The porous cathode mainly functions to form an electronic circuit.
The electrolyte inlet is mainly used for adding electrolyte taking anhydrous HF as a solvent into the electrolytic tank.
The main function of the raw material inlet is to add liquid phase raw material into the electrolytic cell.
The vent of the electrolytic cell is used for discharging waste gas generated in the electrolytic process.
The cooling kettle is mainly used for providing a storage place for liquefied octafluoropropane.
The cooling column is mainly used for providing a gas phase passage for the gas phase component of the electrolytic gas and further cooling the liquefied component in the gas phase component.
The operation of the cooling column vent is to discharge H 2 And (3) an isogas phase component.
The cooling liquid pipeline is used for providing cooling liquid for the cooling kettle and the cooling column.
The liquid phase outlet acts to liquefy the liquid free of H 2 Is fed to a heating mechanism.
The heating mechanism is used for gasifying the liquefied octafluoropropane.
When the device is used for preparing octafluoropropane:
(1) Preparing an electrolyte: and (3) preparing electrolyte by taking alkali fluoride as a conductive agent and anhydrous HF as a solvent at the temperature of 0-10 ℃. Adding the prepared electrolyte into an electrolytic tank through an electrolyte inlet; during electrolysis, the consumed HF is fed to the electrolytic cell through the electrolyte inlet.
(2) Electrolytic water removal and cooling mechanism precooling: since the alkali fluoride contains a trace amount of impurities such as water, it is necessary to remove the trace amount of impurities by electrolysis. The process is to raise the electrolysis voltage from 3V to 4V to 5V to 6V, raise the voltage by 0.4V to 0.6V each time, and observe the trend of electrolysis current and raise the voltage when the current drops to near 0. Finally, when the current drops to approximately 0 at 5V to 6V, it is considered that the electrolyte is free of impurities such as water by electrolysis. The electrolytic gas generated during this period is discharged to the three-waste treatment device through the vent.
And simultaneously, the cooling mechanism is precooled, the temperature of the cooling mechanism is ensured to be between 70 ℃ below zero and 50 ℃ below zero, and preparation is carried out for collecting the octafluoropropane.
(3) Electrolyzing and synthesizing a crude octafluoropropane product: the liquid phase raw material enters the electrolytic tank through the raw material inlet and keeps 5V to 8V running, and the electrolytic gas generated during the operation is discharged to the three-waste treatment device through the vent. By infrared analysis of the electrolysis product, when octafluoropropane is contained in the electrolysis product, the vent is closed, and the gas pipeline connecting the electrolysis tank with the cooling mechanism is opened, so that the electrolysis product contains H 2 The octafluoropropane crude gas enters a cooling mechanism. And simultaneously, according to the current, adjusting the electrolytic voltage to a value required by production.
(4) Collection of octafluoropropane: when the collection of the octafluoropropane crude product gas is started, the temperature of the cooling mechanism is controlled to be between 70 ℃ below zero and 50 ℃ below zero, so that the octafluoropropane gas is ensured to be collected in the cooling mechanism as much as possible. H 2 The gas components are discharged to the three-waste treatment device through the vent. The collection end time can be predicted according to the current and the volume of the cooling mechanism. When the collection is finished, the octafluoropropane in the cooling kettle is gasified by adopting a heating mode.
Example 1
A method for preparing octafluoropropane by electrolysis, comprising the following steps:
(1) HF and KF were mixed at 10℃to obtain a molten salt electrolyte.
(2) And (3) introducing the electrolyte into an electrolytic tank, electrolyzing to remove water, and emptying the electrolytic gas. Specifically, the electrolysis voltage is controlled to be 3V at first, the trend of the electrolysis current is observed, when the current is reduced to 0, the voltage is gradually increased in a segmented mode, 0.5V is increased each time, until the voltage is increased to 5V, and when the current is reduced to 0, the electrolysis water removal is finished. The anode and the cathode in the electrolytic tank are porous nickel plates, and the interval is 5mm.
(3) After the electrolytic water removal is finished, adding the raw materials into an electrolytic tank, controlling the electrolytic voltage to 7V and the electrolytic temperature to-10 ℃, and collecting an electrolytic product to obtain a crude octafluoropropane product when the octafluoropropane is detected to be contained in the electrolytic product; the raw material is butyric anhydride. The mass fraction of KF is 12%, the mass fraction of raw materials is 5% and the balance is HF, calculated by the total mass of the HF, the KF and the raw materials is 100%.
(4) The crude octafluoropropane product was cooled at-60 ℃ using liquid nitrogen and the liquid phase was collected.
(5) And heating and gasifying the liquid phase to obtain the octafluoropropane.
And carrying out infrared analysis on the obtained octafluoropropane crude product, wherein the volume fraction of octafluoropropane in the crude product is 20%.
And (3) carrying out infrared analysis on the finally obtained octafluoropropane, wherein the volume fraction of the octafluoropropane is more than 80%.
Example 2
A method for preparing octafluoropropane by electrolysis, comprising the following steps:
(1) HF and CsF were mixed at 10℃to obtain a molten salt electrolyte.
(2) And (3) introducing the electrolyte into an electrolytic tank, electrolyzing to remove water, and emptying the electrolytic gas. Specifically, the electrolysis voltage is controlled to be 3V at first, the trend of the electrolysis current is observed, when the current is reduced to 0, the voltage is gradually increased in a segmented mode, 0.5V is increased each time, until the voltage is increased to 5V, and when the current is reduced to 0, the electrolysis water removal is finished. The anode and the cathode in the electrolytic tank are porous nickel pipes, and the interval is 5mm.
(3) After the electrolytic water removal is finished, adding the raw materials into an electrolytic tank, controlling the electrolytic voltage to be 6.5V and the electrolytic temperature to be 20 ℃, and collecting an electrolytic product to obtain a crude octafluoropropane product when the octafluoropropane is detected to be contained in the electrolytic product; the raw material is potassium butyrate. The total mass of the HF, the CsF and the raw materials is 100%, the CsF is 10%, the raw materials are 8%, and the balance is HF.
(4) The crude octafluoropropane product was cooled at-60 ℃ using liquid nitrogen and the liquid phase was collected.
(5) And heating and gasifying the liquid phase to obtain the octafluoropropane.
And carrying out infrared analysis on the obtained octafluoropropane crude product, wherein the volume fraction of octafluoropropane in the crude product is 22%.
And (3) carrying out infrared analysis on the finally obtained octafluoropropane, wherein the volume fraction of the octafluoropropane is more than 80%.
Comparative example 1
Mixing HF and KF into electrolyte at 5 ℃ with KF content of 10%; and (3) introducing the electrolyte into an electrolytic tank, wherein the anode and the cathode in the electrolytic tank are nickel plates, the distance is 6mm, and after the electrolytic water removal is finished, introducing raw material gas propane to the surface of the anode, wherein the single-tube air inlet rate is 1300L/h, and the electrolytic voltage is 5.8V. Removing H from the electrolyzed gas by infrared analysis 2 The content of octafluoropropane is less than 10%.
Comparative example 2
(1) HF and KF were mixed at 5℃to obtain a molten salt electrolyte.
(2) And (3) introducing the electrolyte into an electrolytic tank, electrolyzing to remove water, and emptying the electrolytic gas. Specifically, the electrolysis voltage is controlled to be 3V at first, the trend of the electrolysis current is observed, when the current is reduced to 0, the voltage is gradually increased in a segmented mode, 0.5V is increased each time, until the voltage is increased to 5V, and when the current is reduced to 0, the electrolysis water removal is finished. The anode and the cathode in the electrolytic tank are porous nickel plates, and the distance between the anode and the cathode is 1.5mm.
(3) After the electrolytic water removal is finished, adding the raw materials into an electrolytic tank, controlling the electrolytic voltage to be 6V and the electrolytic temperature to be-10 ℃, and collecting an electrolytic product to obtain a crude octafluoropropane product when the octafluoropropane is detected to be contained in the electrolytic product; the raw material is isobutyric anhydride. The mass fraction of KF is 10%, the mass fraction of raw materials is 10% and the balance is HF, calculated by the total mass of the HF, the KF and the raw materials is 100%.
After the electrolytic tank runs for a period of time, the electrolytic tank is closed, after the electrolytic tank continues to run for a period of time, the electrolytic current rises to the upper limit of the rectifying cabinet, after the electrolytic tank is disassembled, the anode and the cathode are adhered together, and Ni-containing precipitate with the middle of about 1mm exists.
Comparative example 3
(1) HF and KF were mixed at 5℃to obtain a molten salt electrolyte.
(2) And (3) introducing the electrolyte into an electrolytic tank, electrolyzing to remove water, and emptying the electrolytic gas. Specifically, the electrolysis voltage is controlled to be 3V at first, the trend of the electrolysis current is observed, when the current is reduced to 0, the voltage is gradually increased in a segmented mode, 0.5V is increased each time, until the voltage is increased to 5V, and when the current is reduced to 0, the electrolysis water removal is finished. The anode and the cathode in the electrolytic tank are porous nickel plates, and the interval is 5mm.
(3) After the electrolytic water removal is finished, adding the raw materials into an electrolytic tank, controlling the electrolytic voltage to be 6.5V, controlling the electrolytic temperature to be-10 ℃, and collecting an electrolytic product to obtain a crude octafluoropropane product when the octafluoropropane is detected to be contained in the electrolytic product; the raw material is isobutyric anhydride. The mass fraction of KF is 8%, the mass fraction of raw materials is 10% and the balance is HF, calculated by the total mass of the HF, the KF and the raw materials being 100%.
(4) The crude octafluoropropane product was cooled at-75 ℃ using liquid nitrogen and the liquid phase was collected.
(5) And heating and gasifying the liquid phase to obtain the octafluoropropane.
After a period of operation, the pressure in the electrolytic tank is increased, and the gas pipeline is blocked. The electrolysis was stopped and the gas line was disconnected, and the appearance of solid particles which instantaneously emitted white irritating gas was found. And stopping the circulation of the cooling liquid, disassembling the cooling column, and generating solid particles which emit white irritant gas at the joint of the gas pipeline and the cold trap column.
In view of the foregoing, it will be appreciated that the invention includes but is not limited to the foregoing embodiments, any equivalent or partial modification made within the spirit and principles of the invention.
Claims (10)
1. A method for preparing octafluoropropane by electrolysis, which is characterized by comprising the following steps: the method comprises the following steps:
(1) Mixing HF and alkali metal fluoride at the temperature of 0-10 ℃ to obtain molten salt electrolyte;
(2) Introducing the electrolyte into an electrolytic tank, electrolyzing to remove water, and emptying electrolytic gas;
(3) After the electrolytic water removal is finished, adding raw materials into an electrolytic tank, controlling the electrolytic voltage to be 4-10V, controlling the electrolytic temperature to be-10-20 ℃, and collecting an electrolytic product to obtain a crude octafluoropropane product when the fact that the electrolytic product contains octafluoropropane is detected; the raw materials are isobutyric anhydride, butyric anhydride or butyric acid metal salt;
(4) Cooling the octafluoropropane crude product at the temperature of-70 to-50 ℃ and collecting a liquid phase;
(5) Heating and gasifying the liquid phase to obtain octafluoropropane;
wherein, the total mass of the HF, the alkali metal fluoride and the raw materials is calculated as 100 percent, the mass fraction of the alkali metal fluoride is 3-15 percent, the mass fraction of the raw materials is 5-15 percent, and the balance is HF.
2. A process for the electrolytic preparation of octafluoropropane as claimed in claim 1, wherein: in the step (1), the alkali metal fluoride is one or more of CsF, liF, KF and NaF.
3. A process for the electrolytic preparation of octafluoropropane as claimed in claim 1, wherein: in the step (2), when water is electrolyzed, the electrolysis voltage is controlled to be 3V-4V at first, the trend of electrolysis current is observed, when the current is reduced to 0, the voltage is increased to be 5V-6V, and when the current is reduced to 0, the water is electrolyzed and removed.
4. A process for the electrolytic preparation of octafluoropropane as claimed in claim 3, wherein: when the voltage is raised, the voltage is raised by 0.4V-0.6V each time.
5. A process for the electrolytic preparation of octafluoropropane as claimed in claim 1, wherein: in the step (3), the metal butyrate is potassium butyrate or sodium butyrate; the electrolysis voltage is 5V-8V.
6. A process for the electrolytic preparation of octafluoropropane as claimed in claim 1, wherein: in the step (4), the cooling temperature is-65 ℃ to-55 ℃; liquid nitrogen or liquid ammonia is adopted for cooling.
7. An apparatus for preparing octafluoropropane by electrolysis according to any one of claims 1 to 6, characterized in that: comprises an electrolytic tank and a cooling and collecting mechanism; the electrolytic tank is relatively provided with a porous anode and a porous cathode, an electrolyte inlet, a raw material inlet, an emptying port and a crude product collecting port are formed in the electrolytic tank, a cooling mechanism in the cooling collecting mechanism is used for collecting the crude octafluoropropane discharged from the crude product collecting port and liquefying the octafluoropropane, and a collecting mechanism in the cooling collecting mechanism is used for collecting the liquefied octafluoropropane and heating and gasifying the liquefied octafluoropropane.
8. An apparatus for the electrolytic production of octafluoropropane as claimed in claim 7, wherein: the cooling collection mechanism comprises a cooling kettle, a cooling column and a heating unit, wherein the top of the cooling kettle is provided with a gas phase outlet and a product outlet; the bottom of the cooling column is communicated with the gas phase outlet, and the top of the cooling column is provided with a cooling column vent; and cooling liquid pipelines are arranged in the cooling kettle and the cooling column, and the heating unit is used for heating the cooling kettle.
9. An apparatus for the electrolytic production of octafluoropropane as claimed in claim 7, wherein: the porous anode and the porous cathode are porous nickel pipes or porous nickel plates.
10. An apparatus for the electrolytic production of octafluoropropane as claimed in claim 7, wherein: the distance between the porous anode and the porous cathode is 3 mm-15 mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111276208.2A CN114016061B (en) | 2021-10-29 | 2021-10-29 | Method and device for preparing octafluoropropane through electrolysis |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111276208.2A CN114016061B (en) | 2021-10-29 | 2021-10-29 | Method and device for preparing octafluoropropane through electrolysis |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114016061A CN114016061A (en) | 2022-02-08 |
| CN114016061B true CN114016061B (en) | 2023-09-08 |
Family
ID=80059144
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111276208.2A Active CN114016061B (en) | 2021-10-29 | 2021-10-29 | Method and device for preparing octafluoropropane through electrolysis |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114016061B (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107604378A (en) * | 2017-10-19 | 2018-01-19 | 浙江巨圣氟化学有限公司 | A kind of preparation method of perfluor hexane |
| CN108441883A (en) * | 2018-03-14 | 2018-08-24 | 黎明化工研究设计院有限责任公司 | A kind of method that electrochemical fluorination prepares perfluor methyl isobutyrate |
| CN112831798A (en) * | 2020-12-29 | 2021-05-25 | 中船重工（邯郸）派瑞特种气体有限公司 | Multistage tubular electrolysis device for preparing octafluoropropane and preparation method |
| CN112899707A (en) * | 2020-09-30 | 2021-06-04 | 中船重工（邯郸）派瑞特种气体有限公司 | Preparation method of hexafluoroethane |
-
2021
- 2021-10-29 CN CN202111276208.2A patent/CN114016061B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107604378A (en) * | 2017-10-19 | 2018-01-19 | 浙江巨圣氟化学有限公司 | A kind of preparation method of perfluor hexane |
| CN108441883A (en) * | 2018-03-14 | 2018-08-24 | 黎明化工研究设计院有限责任公司 | A kind of method that electrochemical fluorination prepares perfluor methyl isobutyrate |
| CN112899707A (en) * | 2020-09-30 | 2021-06-04 | 中船重工（邯郸）派瑞特种气体有限公司 | Preparation method of hexafluoroethane |
| CN112831798A (en) * | 2020-12-29 | 2021-05-25 | 中船重工（邯郸）派瑞特种气体有限公司 | Multistage tubular electrolysis device for preparing octafluoropropane and preparation method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114016061A (en) | 2022-02-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1840742B (en) | Electrolytic anode and method for electrolytically synthesizing fluorine-containing substance using the electrolytic anode | |
| US3288692A (en) | Electrochemical process for the production of organic oxides | |
| US20080314759A1 (en) | Conductive diamond electrode structure and method for electrolytic synthesis of fluorine-containing material | |
| CN107188778B (en) | Preparation method of octafluorocyclopentene | |
| KR101004976B1 (en) | Perfluoro alkanesulfonic acid potassium and preparation method thereof | |
| CN111039749B (en) | Preparation system and method of electronic-grade carbon tetrafluoride | |
| CN111099957B (en) | Purification system and method for electronic-grade carbon tetrafluoride | |
| CN112831798B (en) | Multi-stage tubular electrolysis device for preparing octafluoropropane and preparation method | |
| CN114016061B (en) | Method and device for preparing octafluoropropane through electrolysis | |
| US6919015B2 (en) | Process for manufacturing fluoroolefins | |
| JP5051568B2 (en) | Method for producing potassium perfluoroalkanesulfonate | |
| CN114621177B (en) | Preparation method of fluoroethylene carbonate | |
| EP2484662A1 (en) | Method for producing perfluorosulfonic acid having ether structure and derivative thereof, and surfactant containing fluorine-containing ether sulfonic acid compound and derivative thereof | |
| CN114230549A (en) | A kind of synthetic method of fluorinated vinylene carbonate | |
| CN109652816B (en) | Synthesis of high-purity tungsten hexafluoride by using metal tungsten as anode to electrolyze molten salt | |
| CN115974109B (en) | Preparation method of hexafluorophosphate | |
| JP3115426B2 (en) | Method for producing perfluoro organic compound | |
| CN1174948C (en) | Method for preparing perfluoroethyl | |
| EP2018446B1 (en) | An electrochemical process to prepare a halogenated carbonyl group-containing compound | |
| CN113906165B (en) | Method for producing fluorine gas | |
| CN109468658B (en) | Preparation method of carbonyl fluoride | |
| CN113548942B (en) | Fluorinating agent and method for preparing perfluoroalkane and byproduct fluorohalogen | |
| KR102704746B1 (en) | Equipment and method for fabricating high purity PFTPA | |
| CN116496138B (en) | Preparation method and preparation device system of monofluoromethane | |
| US3497427A (en) | Process for the production of sulfuryl fluoride |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| CB02 | Change of applicant information | ||
| CB02 | Change of applicant information |
Address after: 057550 No. five Weir Road, chemical industry gathering area, Feixiang District, Handan, Hebei, 1 Applicant after: China shipbuilding (Handan) Perry Special Gas Co.,Ltd. Address before: No.1 Weiwu Road, chemical industry gathering area, Feixiang County, Handan City, Hebei Province Applicant before: PERIC SPECIAL GASES Co.,Ltd. |
|
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |