CN111410182A - Method for recycling phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas - Google Patents
Method for recycling phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas Download PDFInfo
- Publication number
- CN111410182A CN111410182A CN202010245625.XA CN202010245625A CN111410182A CN 111410182 A CN111410182 A CN 111410182A CN 202010245625 A CN202010245625 A CN 202010245625A CN 111410182 A CN111410182 A CN 111410182A
- Authority
- CN
- China
- Prior art keywords
- phosphorus pentafluoride
- lithium hexafluorophosphate
- tail gas
- hexafluorophosphate synthesis
- synthesis tail
- 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.)
- Pending
Links
- OBCUTHMOOONNBS-UHFFFAOYSA-N phosphorus pentafluoride Chemical compound FP(F)(F)(F)F OBCUTHMOOONNBS-UHFFFAOYSA-N 0.000 title claims abstract description 82
- -1 lithium hexafluorophosphate Chemical compound 0.000 title claims abstract description 66
- 238000003786 synthesis reaction Methods 0.000 title claims abstract description 52
- 230000015572 biosynthetic process Effects 0.000 title claims abstract description 51
- 238000000034 method Methods 0.000 title claims abstract description 33
- 238000004064 recycling Methods 0.000 title claims abstract description 25
- 239000007789 gas Substances 0.000 claims abstract description 90
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 claims abstract description 21
- 229910000040 hydrogen fluoride Inorganic materials 0.000 claims abstract description 21
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims abstract description 19
- 229910000041 hydrogen chloride Inorganic materials 0.000 claims abstract description 19
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 claims abstract description 19
- 239000002879 Lewis base Substances 0.000 claims abstract description 16
- 150000007527 lewis bases Chemical class 0.000 claims abstract description 16
- 239000007788 liquid Substances 0.000 claims abstract description 14
- 239000007787 solid Substances 0.000 claims abstract description 13
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 18
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical group CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 claims description 10
- 238000005406 washing Methods 0.000 claims description 9
- 239000002250 absorbent Substances 0.000 claims description 8
- 230000002745 absorbent Effects 0.000 claims description 8
- 238000010438 heat treatment Methods 0.000 claims description 8
- 150000001491 aromatic compounds Chemical class 0.000 claims description 7
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 6
- 229910052751 metal Inorganic materials 0.000 claims description 5
- 239000002184 metal Substances 0.000 claims description 5
- 150000002825 nitriles Chemical class 0.000 claims description 5
- 229940078552 o-xylene Drugs 0.000 claims description 5
- JRZJOMJEPLMPRA-UHFFFAOYSA-N olefin Natural products CCCCCCCC=C JRZJOMJEPLMPRA-UHFFFAOYSA-N 0.000 claims description 5
- 150000003839 salts Chemical class 0.000 claims description 5
- DNIAPMSPPWPWGF-GSVOUGTGSA-N (R)-(-)-Propylene glycol Chemical compound C[C@@H](O)CO DNIAPMSPPWPWGF-GSVOUGTGSA-N 0.000 claims description 4
- URLKBWYHVLBVBO-UHFFFAOYSA-N Para-Xylene Chemical group CC1=CC=C(C)C=C1 URLKBWYHVLBVBO-UHFFFAOYSA-N 0.000 claims description 4
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims description 4
- 150000001336 alkenes Chemical class 0.000 claims description 4
- 239000000126 substance Substances 0.000 claims description 4
- 229910052783 alkali metal Inorganic materials 0.000 claims description 2
- WVDDGKGOMKODPV-UHFFFAOYSA-N Benzyl alcohol Chemical compound OCC1=CC=CC=C1 WVDDGKGOMKODPV-UHFFFAOYSA-N 0.000 claims 2
- 150000001412 amines Chemical class 0.000 claims 1
- 239000002994 raw material Substances 0.000 abstract description 5
- 238000010521 absorption reaction Methods 0.000 description 36
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 14
- 230000006872 improvement Effects 0.000 description 10
- 235000019441 ethanol Nutrition 0.000 description 8
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 description 6
- 239000003513 alkali Substances 0.000 description 6
- 239000002253 acid Substances 0.000 description 5
- 230000008859 change Effects 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 5
- 241000282414 Homo sapiens Species 0.000 description 4
- 238000011161 development Methods 0.000 description 4
- 238000012856 packing Methods 0.000 description 4
- UHZYTMXLRWXGPK-UHFFFAOYSA-N phosphorus pentachloride Chemical compound ClP(Cl)(Cl)(Cl)Cl UHZYTMXLRWXGPK-UHFFFAOYSA-N 0.000 description 4
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 4
- 239000004810 polytetrafluoroethylene Substances 0.000 description 4
- 238000011084 recovery Methods 0.000 description 4
- 229910001220 stainless steel Inorganic materials 0.000 description 4
- 239000010935 stainless steel Substances 0.000 description 4
- WEVYAHXRMPXWCK-UHFFFAOYSA-N Acetonitrile Chemical compound CC#N WEVYAHXRMPXWCK-UHFFFAOYSA-N 0.000 description 3
- 238000000926 separation method Methods 0.000 description 3
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 3
- 239000002841 Lewis acid Substances 0.000 description 2
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- 125000001931 aliphatic group Chemical group 0.000 description 2
- 239000003125 aqueous solvent Substances 0.000 description 2
- 239000002585 base Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000003912 environmental pollution Methods 0.000 description 2
- 150000002500 ions Chemical class 0.000 description 2
- 150000007517 lewis acids Chemical class 0.000 description 2
- PQXKHYXIUOZZFA-UHFFFAOYSA-M lithium fluoride Chemical compound [Li+].[F-] PQXKHYXIUOZZFA-UHFFFAOYSA-M 0.000 description 2
- 229910001416 lithium ion Inorganic materials 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 235000011837 pasties Nutrition 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- QDRKDTQENPPHOJ-UHFFFAOYSA-N sodium ethoxide Chemical compound [Na+].CC[O-] QDRKDTQENPPHOJ-UHFFFAOYSA-N 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- ZGEGCLOFRBLKSE-UHFFFAOYSA-N 1-Heptene Chemical compound CCCCCC=C ZGEGCLOFRBLKSE-UHFFFAOYSA-N 0.000 description 1
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- 239000006096 absorbing agent Substances 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000004146 energy storage Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 239000002803 fossil fuel Substances 0.000 description 1
- 238000002309 gasification Methods 0.000 description 1
- 239000002920 hazardous waste Substances 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 238000005342 ion exchange Methods 0.000 description 1
- 238000004255 ion exchange chromatography Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- RHFUXPCCELGMFC-UHFFFAOYSA-N n-(6-cyano-3-hydroxy-2,2-dimethyl-3,4-dihydrochromen-4-yl)-n-phenylmethoxyacetamide Chemical compound OC1C(C)(C)OC2=CC=C(C#N)C=C2C1N(C(=O)C)OCC1=CC=CC=C1 RHFUXPCCELGMFC-UHFFFAOYSA-N 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B25/00—Phosphorus; Compounds thereof
- C01B25/10—Halides or oxyhalides of phosphorus
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D15/00—Lithium compounds
- C01D15/005—Lithium hexafluorophosphate
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Inorganic Chemistry (AREA)
- Gas Separation By Absorption (AREA)
Abstract
The invention provides a recycling method of phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas, wherein the lithium hexafluorophosphate synthesis tail gas contains hydrogen chloride, hydrogen fluoride and phosphorus pentafluoride, Lewis base and the phosphorus pentafluoride in the lithium hexafluorophosphate synthesis tail gas are reacted to form a solid or liquid complex, the solid or liquid complex is separated out, the solid or liquid complex is heated to release the phosphorus pentafluoride, and the released phosphorus pentafluoride is secondarily led into a lithium hexafluorophosphate synthesis system. The method has high utilization rate of raw materials and reduced pollution.
Description
Technical Field
The invention relates to a method for recycling phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas, and belongs to the technical field of lithium hexafluorophosphate synthesis.
Background
From the first half of the twentieth century, with the progress of science and technology, human society has entered a rapid development stage, and the demand for energy has also become greater and greater, and fossil fuel as primary energy has played an immeasurable role in human development so far, but human also faces the problem of energy exhaustion and environmental pollution from this, and the search for alternative novel clean energy becomes a common challenge facing human beings. In the twenty-first century, development and utilization of new energy have been made, and in particular, lithium ion batteries have been successfully used in the fields of traditional 3C (computers, cameras, mobile phones, etc.), electric industry (e.g., electric vehicles), energy storage, etc.
Lithium hexafluorophosphate, a key raw material of lithium ion batteries, has been industrially produced. Lithium hexafluorophosphate has various synthesis methods, such as a gas-solid reaction method, an HF solvent method, an organic solvent method, an ion exchange method and the like, and only an anhydrous hydrogen fluoride non-aqueous solvent method among the above methods has been successfully industrialized. The electrolytic fluorine preparation process of Nissan Kanto electrochemical technology and the phosphorus pentachloride process of Sendai chemical (Morita) in the anhydrous hydrogen fluoride non-aqueous solvent method have respective unique advantages, wherein the phosphorus pentachloride method has the advantages of simple equipment, concise circuit, low cost and the like, and is adopted by most manufacturers.
In the process for synthesizing lithium hexafluorophosphate by the phosphorus pentafluoride method, the main reactions are as follows:
PCl5+5HF→PF5+5HCl
it can be seen that along with the progress of the synthesis reaction, a large amount of synthesis tail gas is often generated, and the components of the tail gas mainly comprise hydrogen chloride, hydrogen fluoride and phosphorus pentafluoride, wherein the hydrogen chloride is generated by the reaction of phosphorus pentachloride and hydrogen fluoride, the phosphorus pentafluoride is generated by incomplete reaction of lithium fluoride and phosphorus pentafluoride, and the hydrogen fluoride is generated by entrainment of the hydrogen chloride and low-boiling-point gasification of the hydrogen fluoride. For the mixed tail gas with complex composition, the current practice of industrial production is to treat the mixed tail gas by a multistage water washing and alkali washing method, which not only causes great hydrogen fluoride loss, low raw material utilization rate and cost rise, but also generates great amount of industrial hazardous wastes, requires special treatment of qualified manufacturers, and further causes cost rise. According to statistics, about one ton of anhydrous hydrogen fluoride enters a three-waste system along with tail gas when one ton of lithium hexafluorophosphate is produced, and the annual hydrogen fluoride loss of a 1000 ton/year lithium hexafluorophosphate production line exceeds ten million yuan RMB. Therefore, it is an object of the present invention to provide a method for efficiently recovering and utilizing components in exhaust gas.
In the mixed acid generated by the recovery of lithium hexafluorophosphate tail gas, the subsequent industrial reuse is greatly limited because of phosphorus. Phosphorus pentafluoride reacts with water after entering an exhaust system to generate phosphoric acid, fluorophosphoric acid and the like, and the phosphorus pentafluoride and hydrogen chloride and hydrogen fluoride belong to protonic acid, and the phosphorus pentafluoride is similar in properties and difficult to separate, so that the problem of restriction on subsequent development and utilization is solved. However, no effective method for separating and recycling phosphorus pentafluoride in the lithium hexafluorophosphate synthesis tail gas exists in the prior art.
Disclosure of Invention
The invention provides a method for recycling phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas, which can effectively solve the problems.
The invention is realized by the following steps:
a method for recycling phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas, wherein the lithium hexafluorophosphate synthesis tail gas contains hydrogen chloride, hydrogen fluoride and phosphorus pentafluoride, and is characterized in that: reacting Lewis base with phosphorus pentafluoride in the lithium hexafluorophosphate synthesis tail gas to form a solid or liquid complex, separating the solid or liquid complex, heating the solid or liquid complex to release phosphorus pentafluoride, purifying the released phosphorus pentafluoride, and then introducing the purified phosphorus pentafluoride into a lithium hexafluorophosphate synthesis system for the second time.
As a further improvement, the lithium hexafluorophosphate synthesis tail gas passes through a gas washing tower which takes Lewis base as an absorbent, then the gas washing tower is heated again to release phosphorus pentafluoride, and the released phosphorus pentafluoride is purified and then is led into a lithium hexafluorophosphate synthesis system for the second time.
As a further improvement, the Lewis base is one or more selected from olefin, alcohol and corresponding metal salt, aromatic compound and derivative thereof and nitrile.
As a further improvement, the olefin is selected from the group consisting of aliphatic olefins and their homologues or aliphatic diolefins and their homologues.
As a further improvement, the alcohol is selected from one or more of aliphatic or aromatic alcohols, and the corresponding metal salt is selected from one or more of alkali metal salts of aliphatic or aromatic alcohols.
As a further improvement, the aliphatic alcohol is selected from methanol or ethanol.
In a further improvement, the chemical formula of the nitrile is represented by R-CN, wherein R can be an aliphatic substituent or an aromatic substituent.
As a further improvement, the aromatic compound and the derivative thereof are selected from one or more of methylbenzene, o-xylene and p-xylene.
As a further improvement, the introduction speed of the lithium hexafluorophosphate synthesis tail gas is 10-20m L/min, the flow rate is very critical, and the ideal absorption rate cannot be achieved by too low or too high flow rate.
As a further improvement, when the aromatic compound and its derivative is o-xylene, the operating temperature of the scrubber is 20 to 40 ℃. This temperature is critical and too high or too low of a temperature can significantly reduce the absorption of phosphorus pentafluoride.
The invention has the beneficial effects that:
the synthesis tail gas of the lithium hexafluorophosphate contains phosphorus pentafluoride, hydrogen fluoride and hydrogen chloride, wherein the phosphorus pentafluoride, the hydrogen fluoride and the hydrogen chloride belong to different types of acids, the phosphorus pentafluoride belongs to Lewis acid, and the hydrogen fluoride and the hydrogen chloride belong to protonic acid. According to different properties of Lewis acid and protonic acid, selecting proper Lewis base, wherein the Lewis base forms a complex with the phosphorus pentafluoride and does not react with hydrogen chloride and hydrogen fluoride, thereby separating the phosphorus pentafluoride from the tail gas mixture. The Lewis base is proper in strength, not too strong or too weak, and if the Lewis base is too strong, the acid-base combination in the formed complex is too firm and is not easy to separate, the phosphorus pentafluoride is difficult to recycle, and if the Lewis base is too weak, the formed complex is not stable enough and is difficult to achieve the separation effect. Through a large number of experiments and theoretical deductions, the invention finds the appropriate Lewis base olefin, alcohol and corresponding metal salt, aromatic compound and derivative thereof, nitrile for separating the phosphorus pentafluoride from the lithium hexafluorophosphate synthesis tail gas, can effectively separate the phosphorus pentafluoride from the lithium hexafluorophosphate synthesis tail gas, and can reintroduce the phosphorus pentafluoride into the lithium hexafluorophosphate synthesis system for separation, thereby solving the problem that the phosphorus pentafluoride in the lithium hexafluorophosphate synthesis tail gas in the prior art is difficult to recycle, reducing the environmental pollution, simultaneously reducing the loss of raw materials, improving the utilization rate of the raw materials and reducing the cost.
The absorption rate of the Lewis base selected by the invention to the phosphorus pentafluoride is up to 64.1 percent, and the Lewis base does not react with the phosphorus pentafluoride to generate a new substance, so that the phosphorus pentafluoride can be effectively separated from the lithium hexafluorophosphate synthesis tail gas, and the phosphorus pentafluoride is released for recycling.
Drawings
Fig. 1 is an ion chromatogram of lithium hexafluorophosphate synthesis tail gas in the embodiment of the present invention.
FIG. 2 is a schematic diagram of a system for recycling phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas in the embodiment of the invention.
Reference numerals: the device comprises a gas washing tower 1, an absorption tower 2, a gas washing tower gas inlet 11, a gas washing tower gas recovery pipe 12, an absorption tower gas inlet 21 and an absorption tower gas outlet 22.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention. Thus, the following detailed description of embodiments of the invention is not intended to limit the scope of the invention as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.
As shown in fig. 2, the gas scrubber 1 and the absorption tower 2 of the system for recycling phosphorus pentafluoride from lithium hexafluorophosphate synthesis tail gas are communicated, the gas scrubber 1 is provided with a gas inlet 11 of the gas scrubber, a gas recycling pipe 12 of the gas scrubber, the absorption tower 2 is provided with a gas inlet 21 of the absorption tower, and a gas outlet 22 of the absorption tower. The scrubber 1 is filled with an absorbent for absorbing phosphorus pentafluoride. The absorption tower 2 is filled with alkali liquor for detecting the content of hydrogen fluoride, hydrogen chloride and phosphorus pentafluoride in the mixed gas.
Example 1
The lithium hexafluorophosphate synthesis tail gas is a mixed gas of hydrogen fluoride, hydrogen chloride and phosphorus pentafluoride. Taking a certain volume of mixed gas to measure the contents of hydrogen fluoride, hydrogen chloride and phosphorus pentafluoride in the mixed gas, wherein the measuring method comprises the following steps: absorbing with three-stage sodium hydroxide lye, the size of the absorption tower is 40mm x 300mm (inner diameter x height), the packing of the absorption tower is PTFE material, pall ring packing is 5mm x phi 5mm, the concentration of sodium hydroxide is 2% (w/w), combining the alkali absorption liquid, and measuring F by ion chromatography-、Cl-And PO4 3-The contents of (b) were 8.664. mu.g/ml, 11.465. mu.g/ml, and 0.931. mu.g/ml, respectively (FIG. 1), according to one molecule of PF5Absorbing the alkali liquor to generate a molecule of PO4 3-And 5 molecules of HF, HCl and PF in a quantitative relationship of mass ratio5The mass ratio of (A) to (B) of (B) is 0.552/0.384/0.064 (w/w).
The mixed gas passes through a PTFE (polytetrafluoroethylene) gas scrubber at the flow rate of 10m L/min, the internal dimension of the gas scrubber is 40mm x 300mm (inner diameter x height), 10 x 10 pall ring packing is filled, the absorbent is o-xylene (excessive), the operation temperature is 30 ℃, the gas from the gas scrubber passes through a three-stage sodium hydroxide alkali absorption tower, the dimension of the absorption tower is the same as that of the gas scrubber, the concentration of sodium hydroxide is 2% (w/w), and the Cl is measured by ion chromatography after alkali absorption liquid is combined-、F-And PO4 3-Is converted into HCl/HF/PF in mass ratio5＝0.57/0.40/0.03，PF5The absorption efficiency of (3) was 53.1%. Heating the scrubber, released PF5Collecting PF from the gas recovery line of the scrubber5After being purified, the gas can enter a lithium hexafluorophosphate synthesis system again through a pipeline, and the heating temperature is 100 ℃. The heating temperature can release the phosphorus pentafluoride, and the phosphorus pentafluoride can not be recycled because the solid or liquid complex is not gasified or other chemical reactions are not generated.
Example 2
The proportion of hydrogen chloride, hydrogen fluoride and phosphorus pentafluoride in the lithium hexafluorophosphate synthesis tail gas is HCl: HF: PF (particle Filter)50.552:0.384:0.064(w/w) (measurement same as example 1). the mixed gas was passed through a PTFE scrubber at a flow rate of 20m L/min, the internal dimensions of the scrubber were 40mm 300mm (internal diameter) height, 10 a 10 pall ring packing was packed, the absorber was n-heptene (excess), the operating temperature was 20 ℃-、F-And PO4 3-Is converted into HCl/HF/PF in mass ratio5＝0.571/0.406/0.023，PF5The absorption efficiency of (3) was 64.1%. Heating the scrubber, released PF5Collecting PF from the gas recovery line of the scrubber5The gas can enter a lithium hexafluorophosphate synthesis system again through a pipeline after being purified, and the heating temperature is 70 ℃.
Example 3
The operating temperature of the scrubber was 10 deg.C, and other operations were the same as in example 1, and the PF was determined5Absorption efficiency of 32.4%. The absorption of this example is significantly lower than that of example 1, indicating that the operating temperature of the scrubber is critical and that temperatures too low can reduce the absorption of phosphorus pentafluoride.
Example 4
The operating temperature of the scrubber was 45 deg.C, and other operations were the same as in example 1, and the PF was determined5The absorption efficiency of (2) was 36.5%. The absorption of this example is significantly lower than that of example 1, indicating that the operating temperature of the scrubber is critical and that excessive temperatures can reduce the absorption of phosphorus pentafluoride.
Example 5
250g of ethanol solution of absorbent 5% sodium ethoxide is added into a 500ml stainless steel container, and then PF with the concentration of 99.5% (V/V) is introduced5While introducing gas, the container was stirred while maintaining the pressure in the container at 0.1MPa and the temperature at 20 ℃ until the pressure did not change any more, and after maintaining the pressure for one hour, the content of the container was taken out as a red liquid weighed 265.75g, and the absorption amount was 15.75g calculated from the change in the front and rear weights. When the temperature rises to 60 ℃, PF5The gas is released. The ethanol solution of the 5% sodium ethoxide has good absorption capacity on phosphorus pentafluoride, and can be used for absorbing and recycling the phosphorus pentafluoride in the lithium hexafluorophosphate synthesis tail gas.
Example 6
250g of absorbent absolute ethyl alcohol is added into a 500ml stainless steel container, PF5 gas with the concentration of 99.5% (V/V) is introduced, stirring is carried out while introducing, the pressure in the container is maintained at 0.1MPa, the temperature is 20 ℃, the content in the container is taken out after the pressure is not changed any more after maintaining for one hour, the content is red liquid, the weight is 262.75, and the absorption amount is 12.75g according to the change of the front weight and the back weight. When the temperature rises to 50 ℃, PF5The gas is released. The anhydrous ethanol has good absorption capacity on phosphorus pentafluoride, and can be used for absorbing and recycling the phosphorus pentafluoride in the lithium hexafluorophosphate synthesis tail gas.
Example 7
250g of tetrahydrofuran as an absorbent is added into a 500ml stainless steel container, then PF5 gas with the concentration of 99.5% (V/V) is introduced, stirring is carried out while introducing, the pressure in the container is maintained at 0.1MPa, the temperature is 20 ℃, the pressure is not changed any more, the content of the container is taken out after maintaining for one hour, the content is gray pasty solid, weighing is 290.5, and the absorption amount is 40.5g according to the change of the front weight and the rear weight. When the temperature rises to 45 ℃, PF5The gas is released. Shows that tetrahydrofuran has good absorption capacity to phosphorus pentafluoride and can be used forAbsorbing and recycling phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas.
Example 8
250g of acetonitrile as an absorbent is added into a 500ml stainless steel container, PF5 gas with the concentration of 99.5% (V/V) is introduced, the container is stirred while introducing, the pressure in the container is maintained at 0.1MPa, the temperature is 15 ℃, the pressure is not changed any more, the content of the container is taken out after maintaining for one hour, the content is gray pasty solid, the weight is weighed to be 280.5, and the absorption is 30.5g according to the change of the front weight and the rear weight. When the temperature rises to 35 ℃, PF5The gas is released. The tetrahydrofuran has good absorption capacity for phosphorus pentafluoride, and can be used for absorbing and recycling phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas.
The absorption strength of the Lewis base selected by the invention is proper, and the Lewis base cannot be too strong or too weak, if the absorption strength is too strong, the acid-base combination in the formed complex is too firm and is not easy to separate, the phosphorus pentafluoride is difficult to recycle, if the absorption strength is too weak, the formed complex is not stable enough, and the separation effect is difficult to achieve.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A method for recycling phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas, wherein the lithium hexafluorophosphate synthesis tail gas contains hydrogen chloride, hydrogen fluoride and phosphorus pentafluoride, and is characterized in that: reacting Lewis base with phosphorus pentafluoride in the lithium hexafluorophosphate synthesis tail gas to form a solid or liquid complex, separating the solid or liquid complex, heating the solid or liquid complex to release phosphorus pentafluoride, purifying the released phosphorus pentafluoride, and then introducing the purified phosphorus pentafluoride into a lithium hexafluorophosphate synthesis system for the second time.
2. The method for recycling phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas by using amine and derivatives thereof as claimed in claim 1, wherein the method comprises the following steps: and (3) enabling the lithium hexafluorophosphate synthesis tail gas to pass through a gas washing tower taking Lewis base as an absorbent, then heating the gas washing tower to release phosphorus pentafluoride, and purifying the released phosphorus pentafluoride and then secondarily introducing the purified phosphorus pentafluoride into a lithium hexafluorophosphate synthesis system.
3. The recycling method of phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas according to claim 2, characterized in that: the Lewis base is one or more selected from olefin, alcohol and corresponding metal salt, aromatic compound and derivative thereof and nitrile.
4. The recycling method of phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas according to claim 3, characterized in that: the olefin is selected from the group consisting of aliphatic olefins and their homologues or aliphatic diolefins and their homologues.
5. The recycling method of phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas according to claim 3, characterized in that: the alcohol is selected from one or more of aliphatic or aromatic alcohol, and the corresponding metal salt is selected from one or more of alkali metal salt of aliphatic or aromatic alcohol.
6. The recycling method of phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas according to claim 5, characterized in that: the aliphatic alcohol is selected from methanol or ethanol.
7. The recycling method of phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas according to claim 3, characterized in that: the chemical general formula of the nitrile is represented as R-CN, wherein R can be an aliphatic substituent or an aromatic substituent.
8. The recycling method of phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas according to claim 3, characterized in that: the aromatic compound and the derivative thereof are selected from one or more of methylbenzene, o-xylene and p-xylene.
9. The recycling method of phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas according to claim 3, characterized in that the feeding speed of the lithium hexafluorophosphate synthesis tail gas is 10-20m L/min.
10. The recycling method of phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas according to claim 8, characterized in that: when the aromatic compound and the derivative thereof are o-xylene, the operating temperature of the scrubber is 20-40 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010245625.XA CN111410182A (en) | 2020-03-31 | 2020-03-31 | Method for recycling phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010245625.XA CN111410182A (en) | 2020-03-31 | 2020-03-31 | Method for recycling phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111410182A true CN111410182A (en) | 2020-07-14 |
Family
ID=71489417
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010245625.XA Pending CN111410182A (en) | 2020-03-31 | 2020-03-31 | Method for recycling phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111410182A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113636535A (en) * | 2021-09-05 | 2021-11-12 | 会昌宏氟高新材料有限责任公司 | Method for recycling lithium difluorophosphate synthesis tail gas |
| CN117923428A (en) * | 2024-01-31 | 2024-04-26 | 河南省氟基新材料科技有限公司 | A comprehensive treatment method for tail gas from lithium hexafluorophosphate process |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1769760A (en) * | 2004-10-15 | 2006-05-10 | 气体产品与化学公司 | Liquid media containing lewis basic reactive compounds for storage and delivery of lewis acidic gases |
| CN1886337A (en) * | 2003-11-28 | 2006-12-27 | 苏威氟有限公司 | Method for enriching phosphorus pentafluoride in phosphorus pentafluoride-hydrogen chloride mixture |
| CN101778793A (en) * | 2007-08-16 | 2010-07-14 | 斯泰拉化工公司 | Process for producing phosphorus pentafluoride and hexafluorophosphate |
| CN104411666A (en) * | 2012-06-29 | 2015-03-11 | 三菱瓦斯化学株式会社 | Method and apparatus for separating alkyl aromatic hydrocarbon |
| WO2017076879A1 (en) * | 2015-11-06 | 2017-05-11 | King's College London | [18f] radiotracers and their uses |
-
2020
- 2020-03-31 CN CN202010245625.XA patent/CN111410182A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1886337A (en) * | 2003-11-28 | 2006-12-27 | 苏威氟有限公司 | Method for enriching phosphorus pentafluoride in phosphorus pentafluoride-hydrogen chloride mixture |
| CN1769760A (en) * | 2004-10-15 | 2006-05-10 | 气体产品与化学公司 | Liquid media containing lewis basic reactive compounds for storage and delivery of lewis acidic gases |
| CN101778793A (en) * | 2007-08-16 | 2010-07-14 | 斯泰拉化工公司 | Process for producing phosphorus pentafluoride and hexafluorophosphate |
| CN104411666A (en) * | 2012-06-29 | 2015-03-11 | 三菱瓦斯化学株式会社 | Method and apparatus for separating alkyl aromatic hydrocarbon |
| WO2017076879A1 (en) * | 2015-11-06 | 2017-05-11 | King's College London | [18f] radiotracers and their uses |
Non-Patent Citations (2)
| Title |
|---|
| 国家环境保护总局: "《空气和废气监测分析方法第四版》", 30 September 2003, 中国环境科学出版社 * |
| 李金鹏: "《新编普通化学》", 31 August 2017 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113636535A (en) * | 2021-09-05 | 2021-11-12 | 会昌宏氟高新材料有限责任公司 | Method for recycling lithium difluorophosphate synthesis tail gas |
| CN117923428A (en) * | 2024-01-31 | 2024-04-26 | 河南省氟基新材料科技有限公司 | A comprehensive treatment method for tail gas from lithium hexafluorophosphate process |
| CN117923428B (en) * | 2024-01-31 | 2025-08-01 | 河南省氟基新材料科技有限公司 | Comprehensive treatment method for lithium hexafluorophosphate process tail gas |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Xiong et al. | The efficient conversion of H 2 S into mercaptan alcohols mediated in protic ionic liquids under mild conditions | |
| US20240055660A1 (en) | Hexafluorophosphate, phosphorus pentafluoride, preparation method therefor and application thereof | |
| CN104844556A (en) | Method for continuously preparing vinylene carbonate by tubular reactor | |
| CN108923092A (en) | A kind of waste and old lithium ionic cell electrolyte processing method | |
| Xiong et al. | An imidazole-based DES serving as a “courier” for the efficient coupling of HCl capture and conversion under mild conditions | |
| CN111410182A (en) | Method for recycling phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas | |
| CN102180457A (en) | Process for preparing lithium hexafluorophosphate by organic solvent method | |
| CN103553004B (en) | Method for continuous preparation of sodium azide | |
| CN101941928B (en) | Synthesis method of sulfhydryl alkyl alcohol | |
| US20120067740A1 (en) | Method for concentrating dilute sulfuric acid and an apparatus for concentrating dilute sulfuric acid | |
| CN104291347A (en) | Preparation method of lithium tetrafluoroborate | |
| CN108745198B (en) | Castor oil-based quaternary ammonium salt emulsifier and preparation method thereof | |
| CN105948000A (en) | Method for preparing lithium bis(fluorosulfonyl)imide from aromatic methyl azide | |
| CN104261440B (en) | Cell-grade anhydrous lithium iodide and preparation method thereof | |
| CN112028047A (en) | Preparation method of lithium difluorophosphate | |
| CN111320154A (en) | Method for recycling phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas by utilizing ester and derivatives thereof | |
| CN102091503A (en) | Chemical method for trapping, fixing and purifying carbon dioxide, sulfur dioxide, sulfur trioxide and nitrogen oxides | |
| CN111410181A (en) | Method for recycling phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas by utilizing ether and derivatives thereof | |
| CN116621129A (en) | A kind of preparation method of bisfluorosulfonimide sodium | |
| CN101838012A (en) | Method for recovering silver sulfate from CODCr measuring waste liquid | |
| CN115090270B (en) | A porous polymer uranium adsorption material and its preparation method | |
| CN111439735A (en) | Method for recycling phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas by using amine and derivatives thereof | |
| CN111285340A (en) | Method for recycling phosphorus pentafluoride in lithium hexafluorophosphate synthesis tail gas by using diethyl carbonate | |
| CN204400883U (en) | Pentamethylene diamine purification system | |
| CN106865553B (en) | A kind of activation method for the resin catalyst preparing trichlorosilane |
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 | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20210513 Address after: No. 30, Gongye Road, Pingpu village, Jiaoyang Town, Shanghang County, Longyan City, Fujian Province, 364000 Applicant after: Fujian Longde new energy Co.,Ltd. Address before: 364000 Jiaoyang Industrial Development Zone, Shanghang County, Longyan City, Fujian Province Applicant before: Fujian Longde new energy Co.,Ltd. |
|
| TA01 | Transfer of patent application right | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200714 |
|
| RJ01 | Rejection of invention patent application after publication |