CN112831798B - Multi-stage tubular electrolysis device for preparing octafluoropropane and preparation method - Google Patents
Multi-stage tubular electrolysis device for preparing octafluoropropane and preparation method Download PDFInfo
- Publication number
- CN112831798B CN112831798B CN202011608003.5A CN202011608003A CN112831798B CN 112831798 B CN112831798 B CN 112831798B CN 202011608003 A CN202011608003 A CN 202011608003A CN 112831798 B CN112831798 B CN 112831798B
- Authority
- CN
- China
- Prior art keywords
- electrolytic
- gas
- anode
- octafluoropropane
- electrolyte
- 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 59
- 229960004065 perflutren Drugs 0.000 title claims abstract description 59
- 238000005868 electrolysis reaction Methods 0.000 title claims abstract description 58
- 238000002360 preparation method Methods 0.000 title abstract description 7
- 239000002994 raw material Substances 0.000 claims abstract description 38
- 239000003792 electrolyte Substances 0.000 claims abstract description 31
- 239000007788 liquid Substances 0.000 claims abstract description 12
- 238000006243 chemical reaction Methods 0.000 claims abstract description 9
- 239000011737 fluorine Substances 0.000 claims abstract description 7
- 229910052731 fluorine Inorganic materials 0.000 claims abstract description 7
- 238000004519 manufacturing process Methods 0.000 claims abstract description 4
- 238000001816 cooling Methods 0.000 claims abstract description 3
- 239000007789 gas Substances 0.000 claims description 105
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 47
- 229910052759 nickel Inorganic materials 0.000 claims description 23
- 238000000034 method Methods 0.000 claims description 19
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 claims description 16
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 13
- 239000001294 propane Substances 0.000 claims description 8
- QQONPFPTGQHPMA-UHFFFAOYSA-N propylene Natural products CC=C QQONPFPTGQHPMA-UHFFFAOYSA-N 0.000 claims description 8
- 125000004805 propylene group Chemical group [H]C([H])([H])C([H])([*:1])C([H])([H])[*:2] 0.000 claims description 8
- UKACHOXRXFQJFN-UHFFFAOYSA-N heptafluoropropane Chemical compound FC(F)C(F)(F)C(F)(F)F UKACHOXRXFQJFN-UHFFFAOYSA-N 0.000 claims description 7
- 239000012535 impurity Substances 0.000 claims description 7
- 229910001515 alkali metal fluoride Inorganic materials 0.000 claims description 5
- 229910052792 caesium Inorganic materials 0.000 claims description 3
- 229910001512 metal fluoride Inorganic materials 0.000 claims description 3
- 229910052700 potassium Inorganic materials 0.000 claims description 3
- 150000003839 salts Chemical class 0.000 claims description 3
- 230000002194 synthesizing effect Effects 0.000 claims description 3
- PXGOKWXKJXAPGV-UHFFFAOYSA-N Fluorine Chemical compound FF PXGOKWXKJXAPGV-UHFFFAOYSA-N 0.000 claims 1
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 abstract description 6
- WZJQNLGQTOCWDS-UHFFFAOYSA-K cobalt(iii) fluoride Chemical compound F[Co](F)F WZJQNLGQTOCWDS-UHFFFAOYSA-K 0.000 description 6
- HCDGVLDPFQMKDK-UHFFFAOYSA-N hexafluoropropylene Chemical group FC(F)=C(F)C(F)(F)F HCDGVLDPFQMKDK-UHFFFAOYSA-N 0.000 description 6
- TXEYQDLBPFQVAA-UHFFFAOYSA-N tetrafluoromethane Chemical compound FC(F)(F)F TXEYQDLBPFQVAA-UHFFFAOYSA-N 0.000 description 6
- 229910021583 Cobalt(III) fluoride Inorganic materials 0.000 description 5
- 238000003682 fluorination reaction Methods 0.000 description 5
- WMIYKQLTONQJES-UHFFFAOYSA-N hexafluoroethane Chemical compound FC(F)(F)C(F)(F)F WMIYKQLTONQJES-UHFFFAOYSA-N 0.000 description 5
- 239000003054 catalyst Substances 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 4
- 239000012043 crude product Substances 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical group [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- 239000012025 fluorinating agent Substances 0.000 description 3
- 239000004215 Carbon black (E152) Substances 0.000 description 2
- 229910021582 Cobalt(II) fluoride Inorganic materials 0.000 description 2
- 241001391944 Commicarpus scandens Species 0.000 description 2
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 2
- 230000005856 abnormality Effects 0.000 description 2
- YCYBZKSMUPTWEE-UHFFFAOYSA-L cobalt(ii) fluoride Chemical compound F[Co]F YCYBZKSMUPTWEE-UHFFFAOYSA-L 0.000 description 2
- 125000001153 fluoro group Chemical group F* 0.000 description 2
- 229930195733 hydrocarbon Natural products 0.000 description 2
- 150000002430 hydrocarbons Chemical class 0.000 description 2
- 229910000040 hydrogen fluoride Inorganic materials 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- NSGXIBWMJZWTPY-UHFFFAOYSA-N 1,1,1,3,3,3-hexafluoropropane Chemical compound FC(F)(F)CC(F)(F)F NSGXIBWMJZWTPY-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 206010059866 Drug resistance Diseases 0.000 description 1
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 239000012298 atmosphere Substances 0.000 description 1
- 238000010923 batch production Methods 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 125000001309 chloro group Chemical group Cl* 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000000539 dimer Substances 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 238000010292 electrical insulation Methods 0.000 description 1
- 239000008151 electrolyte solution Substances 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 150000002222 fluorine compounds Chemical class 0.000 description 1
- 239000012634 fragment Substances 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000004377 microelectronic Methods 0.000 description 1
- 231100000956 nontoxicity Toxicity 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000007039 two-step reaction Methods 0.000 description 1
Images
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
- C25B15/00—Operating or servicing cells
- C25B15/08—Supplying or removing reactants or electrolytes; Regeneration of electrolytes
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)
Abstract
The invention discloses a multi-stage tubular electrolysis device for preparing octafluoropropane by an electrolysis method and a preparation method thereof, wherein the device comprises more than two electrolysis baths, a local porous anode, a cathode, a liquid inlet, a gas pipeline and a gas outlet; wherein the electrolytic bath provides a closed electrolytic environment and stores electrolyte; the anode provides a gas raw material channel and fluorine element for reaction; the cathode constitutes an electronic circuit; adding electrolyte into the electrolytic tank through a liquid inlet; connecting the electrolytic tanks through gas pipelines, cooling the electrolytic gas in the previous electrolytic tank and providing a gas channel; and the crude octafluoropropane gas is mainly discharged through a gas outlet. The invention has the advantages of simple production process, high octafluoropropane yield and the like.
Description
Technical Field
The invention relates to the field of octafluoropropane preparation, and particularly relates to an electrolysis device and a preparation method suitable for preparing octafluoropropane gas by an electrolysis method.
Background
Octafluoropropane has the characteristics of no toxicity, no odor, no combustion, insolubility in water and oil, very low solubility in an organic solvent, good electrical insulation, high dielectric rate, good thermal conductivity, physiological drug resistance and the like, and is widely applied to the industries of electronics, microelectronics, medicines and the like; at present, the preparation method of octafluoropropane basically adopts a chemical synthesis method, and the main route is as follows:
1. the direct gas phase fluorination method of hydrocarbon and hexafluoropropylene, namely the hydrocarbon or hexafluoropropylene is directly fluorinated by elemental fluorine under the action of a catalyst, during the fluorination, the C-C bond is broken, a plurality of fragments are generated, and by-products such as dimer, polymer and the like are generated, so that the yield of octafluoropropane is not high;
2. fluorination of fluorochloroalkanes, i.e. reaction of fluorochloroalkanes with fluorine, gives octafluoropropane. This method has two problems: firstly, unreacted chlorofluoroalkane is difficult to remove in a purification section; secondly, due to the influence of electronegativity of adjacent fluorine atoms, cl atoms are difficult to replace by fluorine atoms, and the conversion rate is low;
3. hexafluoropropylene is subjected to two-step reaction to obtain octafluoropropane. Firstly, reacting hexafluoropropylene and hydrogen fluoride in the presence of a fluorination catalyst to obtain heptafluoropropane; and secondly, reacting heptafluoropropane with fluorine gas in the absence of a catalyst to prepare octafluoropropane. The reaction has high requirements on equipment materials and catalysts.
4. With cobalt trifluoride CoF 3 Fluorinating hexafluoropropylene to octafluoropropane for a fluorinating agent. The method comprises two steps: the first step is that hexafluoropropylene is fluorinated and cobalt trifluoride is converted into cobalt difluoride fluoride; in the second step, the cobalt difluoride is fluorinated to cobalt trifluoride. This results in a batch process, and at the same time, the cobalt trifluoride and the cobalt difluoride are converted into each other continuously, so that the molecular structure in the fluorinating agent is changed continuously, and finally the cobalt trifluoride is pulverized to influence the yield of the octafluoropropane.
In summary, because the chemical synthesis method of octafluoropropane has the problems of complex process or low conversion rate, researchers adopt an electrolytic method to prepare octafluoropropane in one step, the method is to disperse a gas raw material in anhydrous HF for electrolysis, an anode electrolyzes F element in the HF into F free radicals, and the F free radicals react with the gas raw material to generate anode gas containing octafluoropropane; the cathode electrolyzes the H ions in the HF to H elements, which combine to form hydrogen. The method has the advantages of simple process, stable components of anode products 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; in addition, in the actual operation process, the yield of the octafluoropropane can be guaranteed to be not less than 50% only when the height of the electrode exceeds 2m, so that the design and processing difficulty of the electrolytic cell is increased.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a multistage tubular electrolysis device suitable for preparing octafluoropropane gas by an electrolysis method, and the following technical scheme is provided for realizing the purpose of the invention:
a multi-stage tubular electrolysis device for preparing octafluoropropane by an electrolysis method comprises more than two electrolysis baths, a local porous anode, a cathode, a liquid inlet, a gas pipeline and a gas outlet; wherein the electrolytic cell provides a closed electrolytic environment and stores electrolyte; the anode provides a gas raw material channel and fluorine for reaction; the cathode constitutes an electronic circuit; adding electrolyte into the electrolytic tank through a liquid inlet; connecting the electrolytic tanks through gas pipelines, cooling the electrolytic gas in the previous electrolytic tank and providing a gas channel; and the crude octafluoropropane gas is mainly discharged through a gas outlet.
Preferably, the anode is a local porous nickel tube, and the cathode is a nickel tube;
preferably, the distance between the anode and the cathode is 2mm-20mm, the electrolytic voltage is 4V-10V, and the inlet speed of the raw material gas is 50L/h-2000L/h.
Preferably, the distance between the anode and the cathode is preferably 3mm-15mm, the electrolytic voltage is preferably 5V-8V, and the raw material gas inlet rate is preferably 100L/h-1500L/h.
Preferably, the electrolyte is a molten salt of HF and an alkaline metal fluoride, the alkaline metal fluoride being present in an amount of 3% to 15%, including but not limited to CsF, liF, KF, and NaF.
Preferably, the gaseous feed is heptafluoropropane, propane or propylene.
Preferably, the number of the electrolytic cells connected in series is 2-8;
a preparation method for preparing octafluoropropane by adopting the multistage tubular electrolysis device comprises the following steps:
step one, adding electrolyte: preparing HF & xMF at 0-10 deg.C n Adding the prepared electrolyte through a liquid inlet of the electrolytic cell, wherein the metal element M is Cs, li, na or K and the like;
step two, electrolytic dewatering: gradually increasing the electrolysis voltage in sections, and removing water from the electrolyte according to the electrolysis current trend;
step three, electrolyzing and synthesizing a coarse octafluoropropane product: the gas raw material enters the anode area of the first electrolytic tank through the gas inlet, the gas raw material floats between the anode and the cathode through the anode porous area, octafluoropropane and other unfinished perfluorinated gases generated by electrolysis enter the anode area of the second electrolytic tank through the gas pipeline and sequentially pass through other subsequent electrolytic tanks until no unfinished perfluorinated gases exist at the gas outlet.
Preferably, in the electrolysis process of the step one, the consumed HF is supplemented to the electrolytic cell through a feeding port;
preferably, in the water removal in the second step, the electrolysis voltage is increased to 3V-4V, the electrolysis current trend is observed, when the current is reduced to be close to 0, the voltage is increased to 5V-6V, the electrolysis current trend is observed, when the current is reduced to be close to 0, the voltage is increased to 6V-7V, the electrolysis current trend is observed, and when the current is reduced to be close to 0, the electrolyte is considered to be subjected to electrolysis, so that no impurities such as water exist.
Has the advantages that:
according to the invention, the bottom of the nickel tube anode is provided with the hole and then processed into the anode, and the gas raw material is dispersed between the anode and the cathode from bottom to top through the air hole, so that the gas raw material can be converted into an octafluoropropane product as much as possible;
the anode areas of a plurality of electrolytic cells are connected in series through gas pipelines, and the characteristic that octafluoropropane cannot be electrolyzed continuously is utilized, so that octafluoropropane and gas which is not fully perfluorinated and is generated by a first electrolytic cell can be electrolyzed continuously in the electrolytic cells which are connected in series subsequently, the yield of the octafluoropropane is improved, and the problem of difficult design and processing caused by overhigh height is solved.
Drawings
FIG. 1 is a schematic diagram of a multi-stage tubular electrolyzer for the production of octafluoropropane
Wherein, 1,7 is a liquid inlet; 2-an air inlet; 3-gas line; 4, 8-anode; 5, 9-cathode; 6, 10-electrolytic cell; 11-air outlet
Detailed Description
The invention is described in detail below with reference to the accompanying drawing 1:
a multi-stage tubular electrolysis device for preparing octafluoropropane by adopting an electrolysis method comprises more than two electrolysis baths 6 and 10, anodes 4 and 8, cathodes 5 and 9, liquid inlets 1 and 7, a gas pipeline 3 and a gas outlet 11; wherein, the electrolytic tanks 6 and 10 provide a closed electrolytic environment and store electrolyte; the anodes 4 and 8 provide gas raw material channels and fluorine for reaction; the cathodes 5,9 constitute an electronic circuit; adding electrolyte into the electrolytic tanks 6 and 10 through the liquid inlets 1 and 7; the electrolytic tank is connected with the electrolytic tank through a gas pipeline 3, simultaneously the electrolytic gas of the previous electrolytic tank is cooled, and a gas channel is provided; the crude octafluoropropane gas is mainly discharged through a gas outlet 11.
Wherein the anodes 4 and 8 are local porous nickel tubes, and the cathodes 5 and 9 are nickel tubes; the electrolyte is molten salt of HF and alkali metal fluoride, the content of the alkali metal fluoride is 3% -15%, and the electrolyte comprises CsF, liF, KF and NaF; the gas raw material is heptafluoropropane, propane or propylene.
In the invention, the number of the electrolytic cells connected in series is 2-8; when the electrolytic bath is connected in series too much, the crude product gas of the octafluoropropane contains H 2 The probability of gas leakage is increased due to excessive gas pipelines exposed to the environment; once H leaks out 2 And the air forms an explosive gas atmosphere, so that fire or explosion can be caused. In addition, the electrolytic bath is increased, the response of the matched copper bar and the rectifier cabinet is increased, and the electrolytic cost cannot be reduced.
In the present invention, the raw material gas inlet rate of a single electrode is 50L/h to 2000L/h, preferably 100L/h to 1500L/h. The gas raw material inlet rate is too low, the gas raw material is easy to generate carbon chain breakage, the yield of the octafluoropropane is low, and meanwhile, the electrolysis current is too low, so that the cost of unit electric quantity of the electrolysis device is increased; the gas raw material inlet speed is too high, the gas raw material is easy to break carbon chains, the yield of the octafluoropropane is low, and meanwhile, the entrained electrolyte is too much, so that a gas pipeline connected with an electrolytic cell is blocked, and the electrolysis is stopped.
In the invention, the distance between the anode and the cathode is 2mm-20mm, preferably 3mm-15mm; the electrode spacing is too small, firstly, the assembly requirement of the electrolytic cell is too high, when the height of the electrode exceeds 500mm, the electrode is contacted due to 1% of angle error, and the electrolytic cell cannot work; secondly, the space between the electrodes is narrow and easy to be occupied by gas in most space, resulting in too low electrolytic current and too high local temperature, and the nickel anode is corroded to form NiF 2 Substances such as the like block the anode air inlet hole, the electrolysis stops, and the most serious result is NiF 2 The cathode is separated out, so that the electrode is short-circuited, and the electrolytic cell is exploded. The electrode spacing is too large, so that the electrode area of the unit volume of the electrolytic cell is reduced, and the cost is increased; secondly, the electrolytic current is too low, and the yield of the crude octafluoropropane is low.
In the present invention, the electrolytic voltage is 4V to 10V, preferably 5V to 8V. The low voltage can lead to low electrolytic current, low yield of crude octafluoropropane and low conversion rate of octafluoropropane. Too high a voltage will result in F 2 It appears that, firstly, the octafluoropropane yield is reduced; second, will react with H 2 And (4) reacting, and knocking the electrolytic cell.
A method for preparing octafluoropropane by using the multistage tubular electrolysis device comprises the following steps:
step one, adding electrolyte: selection of basic fluorides (MF) n ) Preparing HF & xMF as conducting agent at 0-10 deg.C n Adding the prepared electrolyte through a liquid inlet of the electrolytic cell, wherein the metal element M is Cs, li, na, K and the like; in the electrolysis process, the consumed HF is supplemented to the electrolytic cell through the feeding port.
Step two, electrolytic dewatering: gradually increasing the electrolytic voltage in sections, and removing water from the electrolyte according to the electrolytic current trend: as the alkaline fluoride is dried immediately, trace impurities such as water and the like still exist, and the trace impurities need to be removed in an electrolysis mode. In the process, the electrolytic voltage is increased to 3V-4V, and the electrolytic current trend is observed; when the current is reduced to be close to 0, the voltage is increased to 5V-6V, and the electrolytic current trend is observed; when the current is reduced to be close to 0, the voltage is increased to 6V-7V, and the electrolytic current trend is observed; when the current drops to approximately 0, it is considered that the electrolyte solution is electrolyzed and contains no impurities such as water.
Step three, electrolyzing and synthesizing a crude octafluoropropane product: the gas raw material enters the anode area of the first electrolytic cell through a gas inlet; gas raw materials float between an anode and a cathode through an anode porous area, and octafluoropropane and other incomplete perfluorinated gases generated by electrolysis enter the anode area of the second electrolytic tank through a gas pipeline; octafluoropropane and other incompletely perfluorinated gases drift to the anode and cathode electrolysis in the anode porous area of the second electrolytic cell, and the incompletely perfluorinated gases are converted into octafluoropropane through electrolysis; octafluoropropane and other incompletely fluorinated gases generated by the second electrolytic cell sequentially enter other electrolytic cells through gas pipelines until the incompletely fluorinated gases do not exist at the gas outlet; at this time, octafluoropropane was produced as main impurities of carbon tetrafluoride and hexafluoropropane.
The embodiment 1 and the embodiment 2 are examples of electrolysis carried out by adopting the electrolysis device and parameters such as the number of the electrolytic cells in the range; comparative examples 1 to 3 are examples of electrolysis conducted out of range:
example 1
The number of the experimental electrolytic cells is 5, and the design current is 200A; HF and KF are mixed into electrolyte at 0 ℃, and the content of KF is 10%; the anode is a local porous nickel tube, the cathode is a nickel tube, the distance is 4mm, and the gas raw material is propane or propylene. After the water is electrically removed, the gas raw material enters the area between the anode and the cathode through the local porous nickel tube for electrolysis, the gas inlet rate of a single anode is 1200L/H, the electrolysis voltage is 6.8V, the electrolysis current fluctuates between 130A and 150A, the gas crude product is electrolyzed at the gas outlet, H is removed 2 After the content is finished, the yield of octafluoropropane is over 46 percent, the yield of carbon tetrafluoride and hexafluoroethane is below 30 percent, and the continuous operation for 120 days has no abnormality.
Example 2
The number of the experimental electrolytic cells is 6, and the design current is 200A; HF and KF are mixed into electrolyte at 0 ℃, and the content of KF is 10%; the anode is a local porous nickel tube, the cathode is a nickel tube, the distance is 4mm, and the gas raw material is heptafluoropropane. After the water is electrically removed, the gas raw material enters the area between the anode and the cathode through the local porous nickel tube for electrolysis, the gas inlet rate of a single anode is 1000L/H, the electrolysis voltage is 6.5V, the electrolysis current fluctuates between 110A and 140A, the gas crude product is electrolyzed at the gas outlet, H is removed 2 After the content is finished, the yield of octafluoropropane is more than 57%, the yield of carbon tetrafluoride and hexafluoroethane is below 25%, and the continuous operation for 120 days has no abnormality.
Comparative example 1
The number of the experimental electrolytic cells is 1, and the design current is 200A; HF and KF are mixed into electrolyte at 0 ℃, and the content of KF is 6%; the anode and the cathode are both nickel plates, the distance is 5mm, the gas raw material is propane or propylene, and the gas raw material is conveyed to the surface of the anode through a gas pipeline. After the electro-dewatering is finished, raw material gas is fed, the single tube gas feeding rate is 1000L/H, the electrolytic voltage is 6.5V, H is removed from the electrolytic gas 2 Content, octafluoropropane yield was less than 10%.
Comparative example 2
The number of the experimental electrolytic cells is 3, and the design current is 200A; HF and KF are mixed into electrolyte at 0 ℃, and the content of KF is 8%; the anode is a local porous nickel tube, the cathode is a nickel tube, the distance is 5mm, and the gas raw material is propane or propylene. After the water is electrically removed, the gas raw material enters the area between the anode and the cathode through the local porous nickel tube for electrolysis, the gas inlet rate of a single anode is 20L/H, the electrolysis voltage is 7.6V, the electrolysis current fluctuates between 10A and 30A, the crude product of the electrolysis gas at the gas outlet is removed H 2 After the content is finished, the yield of octafluoropropane is less than 25%, and carbon tetrafluoride and hexafluoroethane account for more than 40%.
Comparative example 3
The number of the experimental electrolytic cells is 5, and the design current is 200A; HF and KF are mixed into electrolyte at 0 ℃, and the content of KF is 10%; the anode is a local porous nickel tube, the cathode is a nickel tube, the distance is 1-2 mm, and the gas raw material is propane or propylene. ElectricityAfter water is removed, gas raw materials enter a region between an anode and a cathode through a local porous nickel tube for electrolysis, the gas inlet rate of a single anode is 1000L/H, the electrolysis voltage is 6.3V, the electrolysis current fluctuates between 120A and 150A, a gas outlet electrolyzes a crude gas, and H is removed 2 After the content is reached, the yield of octafluoropropane is more than 40%, the yield of carbon tetrafluoride and hexafluoroethane is below 30%, the operation lasts for 20 days, the electrolytic cell has clunk, the operation lasts for 40 days, the electrolytic current suddenly rises to the upper limit of a rectifier cabinet, after the cell is disassembled, the anode and the cathode are adhered together, and a precipitate containing Ni with the thickness of about 1mm is arranged in the middle.
The electrolytic device provided by the invention uses heptafluoropropane, propane and propylene as gas-phase raw materials, uses hydrogen fluoride as a fluorinating agent, uses alkali metal fluoride as a conductive medium, uses a porous nickel tube as an anode and a nonporous nickel tube as a cathode, and prepares octafluoropropane by a constant-pressure electrolytic fluorination method.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (8)
1. A multi-stage tubular electrolysis device for preparing octafluoropropane is characterized in that: the device comprises more than two electrolytic tanks, a local porous anode, a cathode, a liquid inlet, a gas pipeline and a gas outlet; wherein the electrolytic cell provides a closed electrolytic environment and stores electrolyte; the anode provides a gas raw material channel and fluorine for reaction; the power supply, the cathode and the anode form an electronic loop; adding electrolyte into the electrolytic cell through a liquid inlet; connecting the electrolytic tanks through gas pipelines, cooling the electrolytic gas in the previous electrolytic tank and providing a gas channel; the crude octafluoropropane gas is mainly discharged through a gas outlet;
the anode is a local porous nickel tube, and the cathode is a nickel tube;
the gas raw material drifts between the anode and the cathode from bottom to top through the porous area at the bottom of the anode, and octafluoropropane is generated through electrolysis;
the distance between the anode and the cathode is 2mm-20mm, the electrolytic voltage is 4V-10V, and the raw material gas inlet speed is 50L/h-2000L/h.
2. The multi-stage tubular electrolyzer of claim 1 characterized in that: the distance between the anode and the cathode is 3-15 mm, the electrolytic voltage is 5-8V, and the raw material gas inlet speed is 100-1500L/h.
3. The multi-stage tubular electrolyzer of claim 1 characterized in that: the electrolyte is molten salt of HF and alkali metal fluoride, the content of the alkali metal fluoride is 3% -15%, and the electrolyte comprises CsF, liF, KF and NaF.
4. The multi-stage tubular electrolyzer of claim 1 characterized in that: the gas raw material is heptafluoropropane, propane or propylene.
5. The multi-stage tubular electrolyzer of claim 1 characterized in that: the number of the electrolytic cells connected in series is 2-8.
6. A production method of octafluoropropane using the multi-stage tubular electrolysis apparatus according to any one of claims 1 to 5, comprising the steps of:
step one, electrolyte is added: preparing HF & xMF electrolyte with alkaline metal fluoride content of 3-15% at 0-10 deg.c, where M is Cs, li, na or K, and replenishing the prepared electrolyte via the liquid inlet of the electrolyzer;
step two, electrolytic dewatering: gradually increasing the electrolytic voltage in sections, and removing water from the electrolyte according to the electrolytic current trend;
step three, electrolyzing and synthesizing a crude octafluoropropane product: the gas raw material enters the anode area of the first electrolytic tank through the gas inlet, the gas raw material floats between the anode and the cathode through the anode porous area, octafluoropropane and other incompletely fluorinated gases generated by electrolysis enter the anode area of the second electrolytic tank through the gas pipeline, and sequentially pass through other subsequent electrolytic tanks until no incompletely fluorinated gases exist at the gas outlet.
7. The method of claim 6, wherein: in the electrolysis process of the first step, the consumed HF is supplemented to the electrolytic cell through a feeding port.
8. The method for producing according to claim 7, characterized in that: in the water removal of the second step, the electrolytic voltage is increased to 3V-4V, the electrolytic current trend is observed, when the current is reduced to be close to 0, the voltage is increased to 5V-6V, the electrolytic current trend is observed, when the current is reduced to be close to 0, the voltage is increased to 6V-7V, the electrolytic current trend is observed, and when the current is reduced to be close to 0, the electrolyte is considered to be electrolyzed to remove anhydrous impurities.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202011608003.5A CN112831798B (en) | 2020-12-29 | 2020-12-29 | Multi-stage tubular electrolysis device for preparing octafluoropropane and preparation method |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202011608003.5A CN112831798B (en) | 2020-12-29 | 2020-12-29 | Multi-stage tubular electrolysis device for preparing octafluoropropane and preparation method |
Publications (2)
Publication Number | Publication Date |
---|---|
CN112831798A CN112831798A (en) | 2021-05-25 |
CN112831798B true CN112831798B (en) | 2022-11-25 |
Family
ID=75925329
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202011608003.5A Active CN112831798B (en) | 2020-12-29 | 2020-12-29 | Multi-stage tubular electrolysis device for preparing octafluoropropane and preparation method |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN112831798B (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN114016061B (en) * | 2021-10-29 | 2023-09-08 | 中船(邯郸)派瑞特种气体股份有限公司 | Method and device for preparing octafluoropropane through electrolysis |
CN115925506B (en) * | 2022-11-30 | 2023-06-23 | 福建省巨颖高能新材料有限公司 | Preparation method of octafluoropropane |
Family Cites Families (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1257184A (en) * | 1968-10-22 | 1971-12-15 | ||
US3840445A (en) * | 1972-05-15 | 1974-10-08 | Phillips Petroleum Co | Two-stage electrochemical octafluoropropane production |
US5387323A (en) * | 1993-08-31 | 1995-02-07 | Minnesota Mining And Manufacturing Company | Process for preparing fluorochemicals |
US5573654A (en) * | 1994-03-04 | 1996-11-12 | Minnesota Mining And Manufacturing Company | Process for making hexafluoropropane and perfluoropropane |
JP4539793B2 (en) * | 2000-08-30 | 2010-09-08 | 昭和電工株式会社 | Octafluoropropane production method and use thereof |
US8507151B2 (en) * | 2008-01-17 | 2013-08-13 | GM Global Technology Operations LLC | Membrane electrode assembly having low surface ionomer concentration |
CN101407923B (en) * | 2008-10-31 | 2010-12-08 | 浙江工业大学 | A method for electrolytically synthesizing succinic acid using an electrochemical tubular reactor |
CA2821788A1 (en) * | 2010-12-15 | 2012-06-21 | Basf Se | Process for the electrochemical fluorination of organic compounds |
CN203976933U (en) * | 2014-07-30 | 2014-12-03 | 天门福临金富精细化工有限公司 | A kind of parallel circulating type is fluoridized electrolyzer |
CN104109881B (en) * | 2014-07-30 | 2017-09-15 | 天门福临金富精细化工有限公司 | A kind of parallel circulating type fluorination electrolytic cell |
CN207276735U (en) * | 2017-02-21 | 2018-04-27 | 广州市新奥环保设备工程有限公司 | A kind of sodium hypochlorite electrolytic cell assembly of multi-channel structure |
CN107098790B (en) * | 2017-06-05 | 2020-12-08 | 广东华特气体股份有限公司 | Method for preparing high-purity octafluoropropane |
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 |
CN111370766A (en) * | 2020-03-24 | 2020-07-03 | 青岛滨海学院 | A kind of electrolyte containing -S-F group compound and electrochemical device thereof |
-
2020
- 2020-12-29 CN CN202011608003.5A patent/CN112831798B/en active Active
Also Published As
Publication number | Publication date |
---|---|
CN112831798A (en) | 2021-05-25 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN1840742B (en) | Electrolytic anode and method for electrolytically synthesizing fluorine-containing substance using the electrolytic anode | |
US4542008A (en) | Electrochemical chlorine dioxide process | |
CN112831798B (en) | Multi-stage tubular electrolysis device for preparing octafluoropropane and preparation method | |
EP2898117B1 (en) | Integrated process for producing oxalic acid from carbon dioxide | |
WO1994025643A1 (en) | Recovery of bromine and preparation of hypobromous acid from bromide solution | |
US3959095A (en) | Method of operating a three compartment electrolytic cell for the production of alkali metal hydroxides | |
IL43321A (en) | Method and apparatus for electrolysis | |
US5108560A (en) | Electrochemical process for production of chloric acid from hypochlorous acid | |
KR910001138B1 (en) | Combined process for production of clorine dioxine and sodium hydroxide | |
EP1573088B1 (en) | Process for manufacturing fluoroolefins | |
EP2426235B1 (en) | Electrochemical process and cell for the preparation of germane | |
US4578159A (en) | Electrolysis of alkali metal chloride brine in catholyteless membrane cells employing an oxygen consuming cathode | |
US3729395A (en) | Process for the production of fluorine | |
NO176724B (en) | Process for Continuous Preparation of Alkali Metal Perchlorate | |
US4046653A (en) | Novel electrolysis method and apparatus | |
KR20000064258A (en) | Method for preparing tetraalkylammonium hydroxide aqueous solution | |
US6200456B1 (en) | Large-scale production of anhydrous nitric acid and nitric acid solutions of dinitrogen pentoxide | |
US4634506A (en) | Process for preparing olefin oxides | |
US4919791A (en) | Controlled operation of high current density oxygen consuming cathode cells to prevent hydrogen formation | |
US4146443A (en) | Introducing feed into externally circulating electrolyte in electrochemical process | |
US4147600A (en) | Electrolytic method of producing concentrated hydroxide solutions | |
JPWO2020039853A1 (en) | Anode for electrolytic synthesis and method for manufacturing fluorine gas | |
US3809629A (en) | Process and apparatus for the production of alkali metal chlorates | |
CN114016061B (en) | Method and device for preparing octafluoropropane through electrolysis | |
US3312610A (en) | Electrolytic process for producing phosphine |
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 | ||
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. |
|
CB02 | Change of applicant information | ||
GR01 | Patent grant | ||
GR01 | Patent grant |