Method for preparing Lewis acid gas

Abstract

The invention belongs to the field of Lewis acid gas preparation, and particularly discloses a method for preparing high-purity Lewis acid gas, the chemical reaction general formula of the high-purity Lewis acid gas is C + AF-+ X-> C + XF-+ A, C + AF-is a non-volatile ionic compound, C + is K +, Cs +, quaternary ammonium cation and imidazole cation, A refers to a Lewis acid gas molecular formula, and X is another solid or liquid Lewis acid. C < + > is a quaternary ammonium cation, the structural general formula of the quaternary ammonium cation is [NR1R2R3R4] < + >, and R1, R2, R3 and R4 are saturated hydrocarbon chains or saturated hydrocarbon chains containing ether bonds. According to the method disclosed by the invention, the reaction in the preparation process is controllable, the product purity is high, the reaction speed is high, continuous production can be carried out, massive transportation and storage of Lewis acid gas are avoided, and the safety problems in links of production, storage, transportation and the like of the Lewis acid gas are fundamentally solved.

Description

Technical Field

[0001] The invention belongs to the field of Lewis acid gas preparation, and more specifically, relates to a method for preparing high-purity Lewis acid gas. Background Art

[0002] Lewis acid gases are widely used, often as raw materials and catalysts in synthesis, and often used for etching and doping in the semiconductor industry. However, Lewis acid gases are usually highly toxic and corrosive, making them difficult to store and transport. Before storage and transportation, they are usually liquefied under high pressure and stored in cylinders. However, if a leak occurs during transportation, it will lead to serious safety accidents.

[0003] Take boron trifluoride as an example. It is an important catalyst widely used in organic synthesis and petrochemical industry. It is used in many organic chemical reactions such as alkylation, polymerization, isomerization, addition, condensation and decomposition. Conventional methods for preparing boron trifluoride include fluoroborate method, fluorite boric anhydride method, fluoroboric acid diazo method, fluorite boric anhydride sulfuric acid method, barium fluoroborate heating method, etc. However, in these conventional preparation methods, such as the fluoroborate method, the decomposition temperature of potassium fluoroborate needs to reach 600℃~700℃, the decomposition temperature of calcium fluoroborate needs to be 300℃~500℃, the fluorite boric anhydride method is to heat the mixture of calcium fluoride and boric anhydride to white heat (white heat temperature 900℃~1200℃), and the sodium fluoride boric anhydride method needs to heat sodium fluoride and boric anhydride to a high temperature molten state. These conventional methods require harsh reaction conditions, extremely high reaction temperature, and complicated processes, which are not suitable for the ready-to-use of boron trifluoride.

[0004] Therefore, Lewis acid gases are more suitable for immediate use, which requires a simple, controllable, safe and efficient method to prepare dangerous Lewis acid gases using solids or liquids that are easy to store as raw materials. Summary of the invention

[0005] In view of the defects of the prior art, the object of the present invention is to provide a method for preparing high-purity Lewis acid gas, aiming to solve the safety problems existing in the existing production of Lewis acid gas.

[0006] To achieve the above object, the present invention provides a method for preparing high-purity Lewis acid gas, characterized in that the general chemical reaction formula is:

[0007] C + AF - +X→C + XF - +A↑

[0008] Among them, C + AF - It is a non-volatile ionic compound, C+ K + , Cs + , quaternary ammonium cation, imidazolium cation, A refers to the Lewis acidic gas molecular formula, X is another solid or liquid Lewis acid, and F is a fluorine atom.

[0009] In the above invention, fluoride ions have strong electronegativity, while Lewis acidic gas A and Lewis acid X have strong electron accepting ability, so Lewis acidic gas A and Lewis acid X may combine with fluoride ions to generate AF. - or XF - , if the Lewis acid X is stronger than A, then AF - It reacts easily with X to generate XF - , while releasing A. Even if the Lewis acidity of X is slightly weaker than that of A, the above reaction can still occur because A is a gas and will escape from the reaction system once it is generated.

[0010] The smooth progress of the above reaction is also related to the + The choice of C + As a cation, if the ionic radius is too small, it will show strong moisture absorption characteristics due to the concentration of positive charge and strong Coulomb interaction, and it is not easy to store it as a reactant for a long time. In addition, C + The positive charge is too concentrated, and it will also show Lewis acidity, directly reacting with AF - F - Combination produces byproducts, leading to C + AF - It is difficult to exist stably. On the other hand, C + It is chemically stable to X and does not contain any functional group that reacts with Lewis acid. + Composition of C + AF - , the order of stability is as follows: H + <Li + <Na + <K + <Cs + <quaternary ammonium cation, so C + Preferably K + , Cs + , quaternary ammonium cation.

[0011] In practical applications, the reaction between a fluorine-containing quaternary ammonium salt and a Lewis acid can be used to obtain a crude acidic gas product, and then the obtained gas is purified to obtain a target product.

[0012] Furthermore, C + It is a quaternary ammonium cation with the general structural formula [NR1R2R3R4]+ , wherein R1, R2, R3 and R4 are saturated hydrocarbon chains or saturated hydrocarbon chains containing ether bonds. In the above invention concept, since the Lewis acidic substance can react with many groups, but will not react chemically with saturated hydrocarbon chains and ether bonds, the stability can be preserved even under heating conditions. In addition, the group containing ether bonds has good flexibility, which can reduce the melting point and increase the fluidity of the entire reaction system. In addition, R cannot be -H, because when the -H group exists, C + The positive charge on the hydrogen atom is likely to be concentrated on the hydrogen atom, directly reacting with F - Combine to produce by-products.

[0013] Further, R1, R2, R3 and R4 are selected from one or more of the following: -CH3, -C2H5, -C3H7, -C4H9, -C5H 11 , -C6H6, -CH2OCH3, -C2H5OCH3 and -C2H5OC2H5. Preferably, R1, R2, R3 and R4 are selected from one to three of the above groups.

[0014] Furthermore, the molecular formula represented by A is selected from one or more of the following: BF3, SO3, SiF4, SOF2, PF5, AsF5 and SF4. The above Lewis acid gases can be reacted with F - Combine to form a stable C + AF - Ionic compound, easy for daily storage.

[0015] Further, X is selected from one or more of the following: phosphoric acid, polyphosphoric acid, sulfuric acid, phosphorus pentoxide, sulfur trioxide, arsenic pentoxide, manganese heptoxide, trifluoromethanesulfonic acid, phthalic anhydride, succinic anhydride, glutaric anhydride, maleic anhydride. X can be selected from one of the above Lewis acids or any combination of two to three thereof.

[0016] Furthermore, a solvent with certain polarity but inert reaction is used in the reaction, specifically N-methyl-N-propylpiperidinium di(trifluoromethylsulfonyl)imide ionic liquid (abbreviated as: PP13TFSI) is selected.

[0017] Furthermore, the reaction is carried out in a water-free and oxygen-free container. Since the reactants or products of this reaction are usually easily hydrolyzed in the air or strongly smoke in the air, this preparation process needs to be carried out in a water-free and oxygen-free container.

[0018] Furthermore, the reaction device and the pipeline are made of one or more of PFA, PTFE, stainless steel, and carbon steel.

[0019] Furthermore, the reaction is performed when Lewis acid gas is needed, and the Lewis acid gas is used immediately or within 12 hours after it is obtained. The required amount of reaction raw materials is determined based on the required amount of Lewis acid gas, thereby avoiding the storage of Lewis acid gas.

[0020] In general, the above technical solution conceived by the present invention has the following technical advantages compared with the prior art:

[0021] In the present invention, C + AF - The reaction between the non-volatile ionic compound and the Lewis acid produces Lewis acidic gas. The preparation process provided by the present invention has controllable reaction, high product purity, fast reaction speed, and can be produced continuously, thus avoiding the large-scale transportation and storage of Lewis acidic gas, and fundamentally solving the safety problems in its production, storage and transportation. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of the equipment for preparing Lewis acid gas in an embodiment of the present invention is given. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0024] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0025] In addition, throughout this specification, "one embodiment", "one example" or similar language indicates that a particular feature, structure or characteristic described in conjunction with the embodiment is included in at least one embodiment of the present invention. Therefore, the phrase "in one embodiment" and similar language may, but do not necessarily, refer to the same embodiment.

[0026] The present invention provides a method for preparing Lewis acidic gas, which utilizes the reaction between a fluorine-containing quaternary ammonium salt and a Lewis acid to obtain a Lewis acidic gas crude product, and then purifies the obtained Lewis acidic gas to obtain a high-purity Lewis acidic gas. The purification method includes a condensation method and a cryogenic distillation method.

[0027] The present invention provides 15 methods for preparing Lewis acid gases. The following are 15 chemical reaction formulas for preparing Lewis acid gases:

[0028] 1.

[0029] 2. K + BF4 - +P2O5→K + P2O5F - +BF3↑

[0030] 3. [N(C3H7)4] + SOF3 - +P2O5→[N(C3H7)4] + P2O5F - +SOF2↑

[0031] 4.

[0032] 5. [N(C2H5)4] + BF4 - +(113%)H3PO4→[N(C2H5)4] + H2PO4 - +HF+BF3↑

[0033] 6. [N(CH2CH2OCH3)4] + SO3F - +As2O5→[N(CH2OCH3)4] + As2O5F - +SO3↑

[0034] 7. [C6H6N(CH3)3] + PF6 - +CF3SO3H→[C6H6N(CH3)3] + CF4SO3H+PF5↑or [C6H6N(CH3)3] + PF6 - +CF3SO3H-[C6H6N(CH3)3] + CF3SO3 - +HF+PF5

[0035] 8.

[0036] 9. [N(C3H7)4]+SiF5 - +H2SO4→[N(C3H7)4] + HSO4 - +HF+SiF4↑

[0037] 10. [N(C3H7)4] + SiF5 - +SO3→[N(C3H7)4] + SO3F - +SiF4↑

[0038] 11. [C2H5OCH2CH2N(CH3)3] + AsF6 - +SO3→[C2H5OCH2CH2N(CH3)3] + SO3F - +AsF5↑

[0039] 12. Cs + SF5 - +H3PO4→Cs + H2PO4 - +HF+SF4↑

[0040] 13.

[0041] 14. [(CH3)3NC2H5OCH3] + BF4 - +Mn2O7→[(CH3)3NC2H5OCH3] + Mn2O7F - +BF3↑

[0042] 15.

[0043] In order for the above reactions to proceed smoothly, they need to be carried out in specific reaction equipment. Figure 1 A schematic diagram of the equipment for preparing Lewis acidic gas in the present invention is given, wherein 1 is a reactor, 2 is a purification reactor, 3 is a gas compressor, 4 is a storage reactor, 5 is a feeding reactor, 6 is a three-way valve, and 7 is a ball valve. The feeding reactor 5 is connected to the reactor 1 through the three-way valve 6 to feed the reactor 1. The reactor 1 is also connected to the purification reactor 2, and the purification reactor 2 is connected to the gas compressor 3. The gas compressor 3 outputs the product through a delivery pipeline, and a ball valve 7 is provided on the delivery pipeline to control the closing and opening of the delivery pipeline. The storage reactor 4 is used to temporarily store Lewis acidic gas. Figure 1 What is shown is a simplified diagram of the equipment for preparing Lewis acid gas, not a specific physical diagram.

[0044] The method of the present invention is further described below in conjunction with specific examples. For 15 Lewis acid reaction chemical formulas, the present invention provides 15 corresponding examples.

[0045] Example 1

[0046] The parts are arranged according to the attached Figure 1 The airtightness of the device was checked before the reaction, and high-purity nitrogen was introduced into the system to expel the air. In the reaction to generate SO3, the gas compressor 3 was not required. 2 kg of glutaric anhydride was added to the reaction kettle 1, and 3.5 kg of [C6H 13 N(C2H5)3]+SO3F - .

[0047] At the beginning of the reaction, the temperature of the reactor 1 is controlled at 60°C by circulating water bath heating. The purification method of the purification reactor 2 in this embodiment is condensation reflux. The temperature of the purification reactor 2 is controlled at about 32°C by water bath method to condense and reflux SO3, thereby refluxing SO3 into the storage reactor 4, and keeping the temperature of the storage reactor 4 at about 35°C.

[0048] Open three-way valve 6, the reaction starts, and slowly add [C6H 13 N(C2H5)3] + SO3F - The continuous addition time is 3 hours, and the reactor 1 is continuously stirred during the reaction.

[0049] After the addition is completed, the reactor 1 is slowly heated to 90° C. to promote the reaction until the pressure in the purification reactor and the storage reactor remains stable, and the reaction is completed.

[0050] After the reaction is completed, the purity of the liquid SO3 in the storage kettle reaches 99.5%.

[0051] The reaction equation involved in this embodiment is:

[0052]

[0053] Example 2

[0054] Each part is divided into Figure 1 Connect them in sequence, check the air tightness of the device before the reaction, and introduce high-purity nitrogen into the system to expel the air. Add 2 kg of K + BF4 - , and add an appropriate amount of liquid PP13TFSI to the reactor until K + BF4 - The solvent can be stirred to promote the smooth progress of the subsequent reaction. 2.5 kg of phosphorus pentoxide is added to the feed kettle 5.

[0055] At the beginning of the reaction, the temperature of the reactor 1 is controlled at 30°C by circulating water bath heating, and the purification reactor 2 is cooled to -20°C to -10°C to remove impurities. The gas passes through the compressor 3 and enters the storage reactor 4, which is kept at room temperature to collect gaseous BF3.

[0056] The three-way valve 6 is opened, the reaction starts, and P2O5 is slowly added to the reactor 1 using a conveyor belt. The addition time is continued for 1.5 hours. During the addition process, the reactor 1 is continuously stirred.

[0057] After the addition is completed, the reactor 1 is slowly heated to 90° C. to promote the reaction until the pressure in the purification reactor and the storage reactor remains stable, and the reaction is completed.

[0058] After the reaction is completed, the purity of the liquid BF3 in the storage kettle reaches 99.9%.

[0059] The reaction equation involved in this embodiment is:

[0060] K + BF4 - +P2O5→K + P2O5F - +BF3↑

[0061] Example 3

[0062] Each part is divided into Figure 1 Connect them in sequence, check the air tightness of the device before the reaction, and introduce high-purity nitrogen into the system to expel the air. Add 4 kg of [N(C3H7)4] + SOF3 - , and add an appropriate amount of liquid PP13TFSI to the reactor until [N(C3H7)4] + SOF3 - It can be stirred in the solvent, thereby promoting the smooth progress of the subsequent reaction. 3 kg of phosphorus pentoxide is added to the feed kettle 5.

[0063] At the beginning of the reaction, the temperature of the reactor 1 is controlled at 40°C by circulating water bath heating, and the purification reactor 2 is cooled to -10°C to -20°C to remove impurities. The gas passes through the compressor 3 and enters the storage reactor 4, which is kept at room temperature to collect gaseous difluorosulfoxide.

[0064] The three-way valve 6 is opened, the reaction starts, and P2O5 is slowly added to the reactor 1 using a conveyor belt. The addition time is continued for 3 hours. During the addition process, the reactor 1 is continuously stirred.

[0065] After the addition is completed, the reactor 1 is slowly heated to 100° C. to promote the reaction until the pressure in the purification reactor and the storage reactor remains stable, and the reaction is completed.

[0066] After the reaction was completed, the purity of the gaseous difluorosulfoxide in the storage kettle reached 99.9%.

[0067] The reaction equation involved in this embodiment is:

[0068] [N(C3H7)4] + SOF3 - +P2O5→[N(C3H7)4] + P2O5F - +SOF2↑

[0069] Example 4

[0070] The parts are arranged according to the attached Figure 1 The reactor 1 was connected in sequence. Before the reaction, the air tightness of the device was checked and high-purity nitrogen was introduced into the system to expel the air. 1 kg of maleic anhydride was added to the reactor 1. 3 kg of Cs was added to the feed reactor 5. + SiF5 - .

[0071] At the beginning of the reaction, a circulating water bath is used to control the temperature of the reactor 1 at about 60°C, and the purification reactor 2 is cooled to -10°C to -20°C to remove impurities. The gas passes through the compressor 3 and enters the storage reactor 4, which is kept at room temperature to collect gaseous silicon tetrafluoride.

[0072] Open three-way valve 6, the reaction starts, and Cs is slowly added to the reactor 1 using a conveyor belt. + SiF5 - The addition time is 2 hours, and the reactor 1 is continuously stirred during the addition process.

[0073] After the addition is completed, the reactor 1 is slowly heated to 110° C. to promote the reaction until the pressure in the purification reactor and the storage reactor remains stable, and the reaction is completed.

[0074] After the reaction was completed, the purity of silicon tetrafluoride in the storage kettle reached 99.9%.

[0075] The reaction equation involved in this embodiment is:

[0076]

[0077] Example 5

[0078] The parts are arranged according to the attached Figure 1 The reactor 1 was connected in sequence. Before the reaction, the air tightness of the device was checked and high-purity nitrogen was introduced into the system to expel the air. 2 kg of polyphosphoric acid was added to the reactor 1. 2.5 kg of [N(C2H5)4] + BF4 - .

[0079] At the beginning of the reaction, the temperature of the reactor 1 is controlled at about 40°C by a circulating water bath, and the purification reactor 2 is cooled to about 3°C ​​to achieve the purpose of removing the impurity HF. The gas passes through the compressor 3 and enters the storage reactor 4, which is kept at room temperature to collect gaseous boron trifluoride.

[0080] Open three-way valve 6, the reaction starts, and slowly add [N(C2H5)4] into reactor 1 using a conveyor belt. + BF4 - The addition time is 2 hours, and the reactor 1 is continuously stirred during the addition process.

[0081] After the addition is completed, the reactor 1 is slowly heated to 110° C. to promote the reaction until the pressure in the purification reactor and the storage reactor remains stable, and the reaction is completed.

[0082] After the reaction was completed, the purity of boron trifluoride in the storage kettle reached 99.5%.

[0083] The reaction equation involved in this embodiment is:

[0084] [N(C2H5)4]+BF4 - +(113%)H3PO4→[N(C2H5)4] + H2PO4 - +HF+BF3↑

[0085] Example 6

[0086] Each part is divided into Figure 1 Connect them in sequence, check the air tightness of the device before the reaction, and introduce high-purity nitrogen into the system to exhaust the air. In the reaction of generating SO3, gas compressor 3 is not required. Add 3.5 kg of [N(CH2CH2OCH3)4] + SO3F - , and add an appropriate amount of liquid PP13TFSI to the reactor until [N(CH2CH2OCH3)4] + SO3F - It can be stirred in the solvent, thus promoting the smooth progress of the subsequent reaction. 3.8 kg of As2O5 was added to the feed kettle 5.

[0087] At the beginning of the reaction, the temperature of the reactor 1 is controlled at 35°C by circulating water bath heating. The purification method of the purification reactor 2 in this embodiment is condensation reflux. The temperature of the purification reactor 2 is controlled at about 33°C by water bath method to condense and reflux SO3, thereby refluxing SO3 into the storage reactor 4, and keeping the temperature of the storage reactor 4 at about 33°C.

[0088] Open three-way valve 6, the reaction starts, and slowly add [N(CH2CH2OCH3)4] + SO3F - The continuous addition time is 2.5h, and the reactor 1 is continuously stirred during the reaction.

[0089] After the addition is completed, the reactor 1 is slowly heated to 80° C. to promote the reaction until the pressure in the purification reactor and the storage reactor remains stable, and the reaction is completed.

[0090] After the reaction is completed, the purity of the liquid SO3 in the storage kettle reaches 99.7%.

[0091] The reaction equation involved in this embodiment is:

[0092] [N(CH2CH2OCH3)4] + SO3F - +As2O5→[N(CH2OCH3)4] + As2O5F - +SO3↑

[0093] Example 7

[0094] Each part is divided into Figure 1 Connect them in sequence, check the air tightness of the device before the reaction, and introduce high-purity nitrogen into the system to expel the air. Add 2kg of [C6H6N(CH3)3] + PF6 - . 1.5 kg of trifluoromethanesulfonic acid was added to the feed kettle 5.

[0095] At the beginning of the reaction, the temperature of the reactor 1 is controlled at about 15°C by a circulating water bath, and the purification reactor 2 is cooled to about 5°C to achieve the purpose of removing the impurity HF. The gas passes through the compressor 3 and enters the storage reactor 4, which is kept at room temperature to collect gaseous phosphorus pentafluoride.

[0096] The three-way valve 6 was opened to start the reaction. Trifluoromethanesulfonic acid was slowly added to the reactor 1 over a period of 1 hour. During the addition process, the reactor 1 was continuously stirred.

[0097] After the addition is completed, the reactor 1 is slowly heated to 120° C. to promote the reaction until the pressure in the purification reactor and the storage reactor remains stable, and the reaction is completed.

[0098] After the reaction was completed, the purity of phosphorus pentafluoride in the storage kettle reached 99.6%.

[0099] The reaction equation involved in this embodiment is:

[0100] [C6H6N(CH3)3]+ PF6 - +CF3SO3H→[C6H6N(CH3)3] + CF4SO3H+PF5↑

[0101] Or: [C6H6N(CH3)3] + PF6 - +CF3SO3H→[C6H6N(CH3)3] + CF3SO3 - +HF+PF5

[0102] Example 8

[0103] The parts are arranged according to the attached Figure 1 The air tightness of the device was checked before the reaction, and high-purity nitrogen was introduced into the system to expel the air. 2.5 kg of [N(C6H 13 )4] + PF6 - , and add an appropriate amount of liquid PP13TFSI to the reactor until [N(C6H 13 )4] + PF6 - The solvent can be stirred to promote the smooth progress of the subsequent reaction. 1 kg of phthalic anhydride is added to the feed kettle 5.

[0104] At the beginning of the reaction, the temperature of the reactor 1 is controlled at about 40°C by a circulating water bath, and the purification reactor 2 is cooled to about 3°C ​​to remove the impurity HF. The gas passes through the compressor 3 and enters the storage reactor 4, which is kept at room temperature to collect gaseous phosphorus pentafluoride.

[0105] The three-way valve 6 was opened, the reaction started, and phthalic anhydride was slowly added to the reactor 1 for 1 hour. During the addition process, the reactor 1 was continuously stirred.

[0106] After the addition is completed, the reactor 1 is slowly heated to 100° C. to promote the reaction until the pressure in the purification reactor and the storage reactor remains stable, and the reaction is completed.

[0107] After the reaction was completed, the purity of phosphorus pentafluoride in the storage kettle reached 99.8%.

[0108] The reaction equation involved in this embodiment is:

[0109]

[0110] Example 9

[0111] The parts are arranged according to the attached Figure 1Connect them in sequence, check the air tightness of the device before the reaction, and introduce high-purity nitrogen into the system to expel the air. Add 4 kg of [N(C3H7)4] + SiF5 - . Add 2 kg of concentrated sulfuric acid into the feed kettle 5.

[0112] At the beginning of the reaction, the temperature of the reactor 1 is controlled at about 15°C by a circulating water bath, and the purification reactor 2 is cooled to about 0°C to remove the impurity HF. The gas passes through the compressor 3 and enters the storage reactor 4, which is kept at room temperature to collect gaseous silicon tetrafluoride.

[0113] The three-way valve 6 was opened, the reaction started, and concentrated sulfuric acid was slowly added to the reactor 1 for 2 hours. During the addition process, the reactor 1 was continuously stirred.

[0114] After the addition is completed, the reactor 1 is slowly heated to 120° C. to promote the reaction until the pressure in the purification reactor and the storage reactor remains stable, and the reaction is completed.

[0115] After the reaction was completed, the purity of silicon tetrafluoride in the storage kettle reached 99.8%.

[0116] The reaction equation involved in this embodiment is:

[0117] [N(C3H7)4] + SiF5 - +H2SO4→[N(C3H7)4] + HSO4 - +HF+SiF4↑

[0118] Example 10

[0119] The parts are arranged according to the attached Figure 1 The air tightness of the device was checked before the reaction, and high-purity nitrogen was introduced into the system to expel the air. 3.5 kg of sulfur trioxide was added to the reactor 1, and 1.2 kg of [N(C3H7)4] + SiF5 - .

[0120] At the beginning of the reaction, the temperature of the reactor 1 is controlled at 33°C by circulating water bath heating, and the purification reactor 2 is cooled to about 10°C to achieve the purpose of removing impurities. The gas passes through the compressor 3 and enters the storage reactor 4, which collects gaseous silicon tetrafluoride at room temperature.

[0121] Open three-way valve 6, the reaction starts, and slowly add [N(C3H7)4] + SiF5 -The addition time is 4 hours, and the reactor 1 is continuously stirred during the reaction. After the dropwise addition is completed, the reactor 1 is slowly heated to 80°C to promote the reaction until the pressure in the purification reactor and the storage reactor remains stable, and the reaction is completed.

[0122] After the reaction was completed, the purity of silicon tetrafluoride in the storage kettle reached 99.7%.

[0123] The reaction equation involved in this embodiment is:

[0124] [N(C3H7)4]+SiF5 - +SO3→[N(C3H7)4] + SO3F - +SiF4↑

[0125] Embodiment 11

[0126] Each part is divided into Figure 1 4 kg of sulfur trioxide was added to the reactor 1, and 1.5 kg of [C2H5OCH2CH2N(CH3)3] was added to the feed reactor 5. + AsF6 - .

[0127] At the beginning of the reaction, the temperature of the reactor 1 is controlled at 32°C by circulating water bath heating, and the purification reactor 2 is cooled to about 5°C to achieve the purpose of removing impurities. The gas passes through the compressor 3 and enters the storage reactor 4, which collects gaseous arsenic pentafluoride at room temperature.

[0128] Open three-way valve 6, the reaction starts, and slowly add [C2H5OCH2CH2N(CH3)3] into the reactor 1 + AsF6 - The continuous addition time is 4 hours, and the reactor 1 is continuously stirred during the reaction.

[0129] After the dropwise addition was completed, the reactor 1 was slowly heated to 90° C. to promote the reaction until the pressure in the purification reactor and the storage reactor remained stable, and the reaction was completed.

[0130] After the reaction is completed, the purity of arsenic pentafluoride in the storage kettle reaches 99.7%.

[0131] The reaction equation involved in this embodiment is:

[0132] [C2H5OCH2CH2N(CH3)3] + AsF6 - +SO3→[C2H5OCH2CH2N(CH3)3] + SO3F- +AsF5↑

[0133] Example 12

[0134] Each part is divided into Figure 1 Connect them in sequence, check the air tightness of the device before the reaction, and introduce high-purity nitrogen into the system to expel the air. Add 4 kg of Cs + SF5 - . Add 2 kg of phosphoric acid into the feed kettle 5.

[0135] At the beginning of the reaction, the temperature of the reactor 1 is controlled at about 15°C by a circulating water bath, and the purification reactor 2 is cooled to about 5°C to achieve the purpose of removing the impurity HF. The gas passes through the compressor 3 and enters the storage reactor 4, which is kept at room temperature to collect gaseous sulfur tetrafluoride.

[0136] The three-way valve 6 was opened, the reaction started, and phosphoric acid was slowly added to the reactor 1 for 2.5 hours. During the addition process, the reactor 1 was continuously stirred.

[0137] After the addition is completed, the reactor 1 is slowly heated to 100° C. to promote the reaction until the pressure in the purification reactor and the storage reactor remains stable, and the reaction is completed.

[0138] After the reaction is completed, the purity of sulfur tetrafluoride in the storage kettle reaches 99.8%.

[0139] The reaction equation involved in this embodiment is:

[0140] Cs + SF5 - +H3PO4→Cs + H2PO4 - +HF+SF4↑Example 13

[0141] Each part is divided into Figure 1 Connect them in sequence, check the air tightness of the device before the reaction, and introduce high-purity nitrogen into the system to expel the air. Add 2kg of [N(C4H9)4] + BF4 - , and add an appropriate amount of liquid PP13TFSI to the reactor until [N(C4H9)4] + BF4 - The solvent can be stirred to promote the smooth progress of the subsequent reaction. 0.9 kg of succinic anhydride was added to the feed kettle 5.

[0142] At the beginning of the reaction, the temperature of the reactor 1 is controlled at 50°C by circulating water bath heating, and the purification reactor 2 is cooled to about -30°C to remove impurities. The gas passes through the compressor 3 and enters the storage reactor 4, which is kept at room temperature to collect gaseous BF3.

[0143] Open three-way valve 6, the reaction starts, and slowly add [N(C4H9)4] into the reactor 1 using a conveyor belt. + BF4 - The addition time is 1 hour, and the reactor 1 is continuously stirred during the addition process. After the addition is completed, the reactor 1 is slowly heated to 90°C to promote the reaction until the pressure in the purification reactor and the storage reactor remains stable, and the reaction is completed.

[0144] After the reaction is completed, the purity of the liquid BF3 in the storage kettle reaches 99.9%.

[0145] The reaction equation involved in this embodiment is:

[0146]

[0147] Embodiment 14

[0148] Each part is divided into Figure 1 Connect them in sequence, check the air tightness of the device before the reaction, and introduce high-purity nitrogen into the system to expel the air. Add 4 kg of [(CH3)3NC2H5OCH3] + BF4 - , and add an appropriate amount of liquid PP13TFSI to the reactor until [N(C3H7)4] + SOF3 - It can be stirred in the solvent, thus promoting the smooth progress of the subsequent reaction. 4 kg of Mn2O7 is added to the feed kettle 5.

[0149] At the beginning of the reaction, the temperature of the reactor 1 is controlled at 45°C by circulating water bath heating, and the purification reactor 2 is cooled to about -30°C to remove impurities. The gas passes through the compressor 3 and enters the storage reactor 4 to maintain room temperature and collect gaseous BF3.

[0150] The three-way valve 6 is opened, the reaction starts, and Mn2O7 is slowly added to the reactor 1 using a conveyor belt. The addition time is continued for 3 hours. During the addition process, the reactor 1 is continuously stirred.

[0151] After the addition is completed, the reactor 1 is slowly heated to 100° C. to promote the reaction until the pressure in the purification reactor and the storage reactor remains stable, and the reaction is completed.

[0152] After the reaction is completed, the purity of gaseous BF3 in the storage kettle reaches 99.9%.

[0153] The reaction equation involved in this embodiment is:

[0154] [(CH3)3NC2H5OCH3] + BF4 - +Mn2O7→[(CH3)3NC2H5OCH3] + Mn2O7F - +BF3↑

[0155] Embodiment 15

[0156] Each part is divided into Figure 1 Connect them in sequence, check the air tightness of the device before the reaction, and introduce high-purity nitrogen into the system to exhaust the air. In the reaction of generating SO3, gas compressor 3 is not required. Add 3.5 kg of [N(C6H6)4] + SO3F - , add 1.3 kg of maleic anhydride into the feeding kettle 5.

[0157] At the beginning of the reaction, the temperature of the reactor 1 is controlled at 60°C by circulating water bath heating. The purification method of the purification reactor 2 in this embodiment is condensation reflux. The temperature of the purification reactor 2 is controlled at about 32°C by water bath method to condense and reflux SO3, thereby refluxing SO3 into the storage reactor 4, and keeping the temperature of the storage reactor 4 at about 34°C.

[0158] Open three-way valve 6, the reaction starts, and slowly add [C6H 13 NC2H5)3] + SO3F - The addition time is 2h, and the reactor 1 is continuously stirred during the reaction.

[0159] After the addition is completed, the reactor 1 is slowly heated to 90° C. to promote the reaction until the pressure in the purification reactor and the storage reactor remains stable, and the reaction is completed.

[0160] After the reaction is completed, the purity of the liquid SO3 in the storage kettle reaches 99.6%.

[0161] The reaction equation involved in this embodiment is:

[0162]

[0163] In the present invention, in order to better explain the method of the present invention, it is necessary to explain the concept of Lewis acid. Lewis acid, also known as electrophilic reagent, refers to a substance (including ions, atomic groups or molecules) that can accept electron pairs. This is determined based on the definition of acid in Gilbert Newton Lewis' acid-base electronic theory. Since it includes a wide range of substances, it is also called a generalized acid. Lewis acidic gas refers to a gas that can accept electron pairs.

[0164] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing high-purity Lewis acid gas, characterized in that: The general chemical reaction formula is: C + OF - +X→C + XF - +A↑ Among them, C + AF - It is a non-volatile ionic compound, C + K + , Cs + , quaternary ammonium cation, imidazolium cation, A refers to the Lewis acidic gas molecular formula, X is another solid or liquid Lewis acid, and F is a fluorine atom.

2. The method according to claim 1, characterized in that C + It is a quaternary ammonium cation with the general structural formula [NR1R2R3R4] + , wherein R1, R2, R3 and R4 are saturated hydrocarbon chains or saturated hydrocarbon chains containing ether bonds.

3. The method according to claim 2, characterized in that R1, R2, R3 and R4 are selected from one or more of the following: -CH3, -C2H5, -C3H7, -C4H9, -C5H 11 , -C6H6, -CH2OCH3, -C2H5OCH3 and -C2H5OC2H5.

4. The method according to any one of claims 1 to 3, characterized in that: The molecular formula represented by A is selected from one or more of the following: BF3, SO3, SiF4, SOF2, PF5, AsF5 and SF4.

5. The method according to claim 4, characterized in that X is selected from one or more of the following: phosphoric acid, polyphosphoric acid, sulfuric acid, phosphorus pentoxide, sulfur trioxide, arsenic pentoxide, manganese heptoxide, trifluoromethanesulfonic acid, phthalic anhydride, succinic anhydride, glutaric anhydride, maleic anhydride, and X can be selected from one of the above Lewis acids or any combination of two to three thereof.

6. The method according to claim 1, characterized in that The reaction uses a polar but inert solvent, specifically N-methyl-N-propylpiperidinium di(trifluoromethylsulfonyl)imide ionic liquid.

7. The method according to claim 1, characterized in that The reaction is carried out in an anhydrous and oxygen-free container.

8. The method according to claim 1, characterized in that The reaction device and the pipeline are made of one or more of PFA, PTFE, stainless steel and carbon steel.

9. The method according to claim 1, characterized in that The reaction is performed when Lewis acid gas is needed, and the Lewis acid gas is used immediately or within 12 hours after it is obtained. The amount of reaction raw materials required is determined based on the required amount of Lewis acid gas, and there is no need to store Lewis acid gas.

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