JP2021120352A - Method for producing fluoroolefin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for efficiently producing a fluoroolefin in a liquid phase from hydrofluorocarbon (HFC) or hydrochlorofluorocarbon (HCFC). SOLUTION: In a reactor in which the temperature and pressure can be adjusted, the number of carbon atoms is 3 to 7, and a hydrogen atom and a fluorine atom or a chlorine atom are bonded to two adjacent carbon atoms, respectively. A method for producing a fluoroolefin, which comprises contacting an HFC or HCFC in a molecule with an alkaline aqueous solution in a liquid phase and dehalogenating the HFC or HCFC to obtain a fluoroolefin, wherein the temperature and pressure in the reactor are obtained. A production method for adjusting the above conditions to be above the vapor pressure curve of HFC or HCFC and below the vapor pressure curve of fluoroolefin. [Selection diagram] Fig. 1

Description

The present invention relates to a method for efficiently producing a fluoroolefin, specifically a hydrofluoroolefin, a perfluoroolefin, a hydrochlorofluoroolefin or a chlorofluoroolefin in a liquid phase.

In recent years, hydrofluorocarbons and hydrochlorofluorocarbons have been used for cleaning agents, refrigerants, foaming agents, solvents, aerosol applications and the like. However, it has been pointed out that these compounds may cause global warming. Therefore, halogenated olefins are attracting attention as compounds having a small global warming potential.

As one of the methods for producing a halogenated olefin, dehydrogenated hydrogen fluoride or hydrochlorofluorocarbon having a structure in which a hydrogen atom and a fluorine atom or a chlorine atom are bonded to two adjacent carbon atoms, respectively. Alternatively, a reaction to defluoride hydrogen is known.

For example, Patent Document 1 describes a _{reaction in which XCF 2} CF ₂ CHClY is defluorinated to hydrogen to obtain XCF ₂ CF = CClY (X and Y are fluorine atoms or chlorine atoms, respectively), and 1,1 , 1, 2, 3, 3-Hexafluoro-3-chloropropane is dehydrogenated to obtain hexafluoropropene.

Patent Document 2 describes a method for producing 1-chloro-2,3,3-trifluoropropene by subjecting 1-chloro-2,2,3,3-tetrafluoropropane to a hydrogen fluoride reaction. In Patent Document 3, 1,1-dichloro-2,2,3,3,3-pentafluoropropane is reacted with hydrogen fluoride to cause 1,1-dichloro-2,3,3,3-tetrafluoro. It describes how to get a propen.

In any of these patent documents, an example is described in which the dehydrochlorination or defluorination hydrogen reaction of hydrofluorocarbon or hydrochlorofluorocarbon is carried out by using an alkaline aqueous solution in a liquid phase reaction. In these reactions, the reaction time is long, and therefore, although improvements such as the use of a phase transfer catalyst have been made, a method capable of producing more efficiently has been required.

Japanese Patent No. 3778298 International Publication No. 2017/01/8412 International Publication No. 2010/074254

The present invention has been made from the above viewpoint and efficiently fluoroolefins, specifically, hydrofluoroolefins, perfluoroolefins, hydrochlorofluoroolefins or chlorofluoroolefins from hydrofluorocarbons or hydrochlorofluorocarbons in a liquid phase. The purpose is to provide a method for manufacturing.

The present invention provides a method for producing a fluoroolefin having the following configurations [1] to [8].
[1] In a reactor in which the temperature and pressure can be adjusted, a structure in which the number of carbon atoms is 3 to 7 and a hydrogen atom and a fluorine atom or a chlorine atom are bonded to two adjacent carbon atoms, respectively. Hydrofluorocarbons or hydrochlorofluorocarbons contained in the molecule are brought into contact with an alkaline aqueous solution in a liquid phase, and the hydrofluorocarbons or hydrochlorofluorocarbons are dechlorinated or defluorinated by hydrogenation to hydrofluoroolefins, perfluoroolefins, hydrochlorofluoroolefins. And a method for producing a fluoroolefin, which obtains at least one fluoroolefin selected from chlorofluoroolefins.
A production method for adjusting the temperature and pressure in the reactor to conditions above the vapor pressure curve of the hydrofluorocarbon or hydrochlorofluorocarbon and below the vapor pressure curve of the fluoroolefin.
[2] The production method according to [1], wherein the pressure is adjusted by discharging the gas phase in the reactor to the outside of the reactor.

[3] The production method according to [1] or [2], wherein the hydrofluorocarbon or hydrochlorofluorocarbon is monochlorotetrafluoropropane and the fluoroolefin is tetrafluoropropene.
[4] The monochlorotetrafluoropropane is 2-chloro-1,1,1,2-tetrafluoropropane and / or 3-chloro-1,1,1,2-tetrafluoropropane, and the tetrafluoropropene is The production method according to [3], which is 2,3,3,3-tetrafluoropropene.
[5] The production method according to [4], wherein the pressure in the reactor is adjusted to 2.0 MPaG or less.
[6] The production method according to [1] or [2], wherein the hydrofluorocarbon or hydrochlorofluorocarbon is dichlorotetrafluoropropane, and the fluoroolefin is monochlorotetrafluoropropene.
[7] The dichlorotetrafluoropropane is 2,3-dichloro-1,1,1,2-tetrafluoropropane and / or 3,3-dichloro-1,1,1,2-tetrafluoropropane. The production method according to [6], wherein the monochlorotetrafluoropropene is 1-chloro-2,3,3,3-tetrafluoropropene.
[8] The production method according to [7], wherein the pressure in the reactor is adjusted to 0.5 MPaG or less.

According to the present invention, fluoroolefins, specifically hydrofluoroolefins, perfluoroolefins, hydrochlorofluoroolefins or chlorofluoroolefins, can be efficiently produced from hydrofluorocarbons or hydrochlorofluorocarbons in a liquid phase.

Further, since the production method of the present invention is carried out by a liquid phase reaction, a reactor smaller than that of a gas phase reaction can be adopted, which is industrially advantageous.

It is a graph which shows the vapor pressure curve of 244bb and 1234yf. It is a graph which shows the vapor pressure curve of 234bb and 1224yd (Z) and 1224yd (E). It is the schematic which shows an example of the reaction apparatus used in the manufacturing method of the fluoroolefin of this invention.

Hereinafter, embodiments of the present invention will be described.
In the present specification, for halogenated hydrocarbons, the abbreviation of the compound is described in parentheses after the compound name, but in the present specification, the abbreviation is used instead of the compound name as necessary. Further, as an abbreviation, only the number after the hyphen (−) and the lowercase alphabetic part (for example, “1224yd” in “HCFO-1224yd”) may be used. Further, (E) attached to the name of the compound having a geometric isomer and its abbreviation indicates an E form (trans form), and (Z) indicates a Z form (cis form). When the E-form and Z-form are not specified in the names and abbreviations of the compounds, the names and abbreviations mean E-forms, Z-forms, and generic names including a mixture of E-forms and Z-forms.

In the present specification, the reaction represented by the reaction formula (1) is referred to as a reaction (1). The same applies to the reactions expressed by other formulas. In the present specification, the compound represented by the formula (A) is referred to as a compound (A). The same applies to compounds represented by other formulas. In the present specification, "~" representing a numerical range includes upper and lower limits.

The Hansen solubility parameter of a compound (hereinafter, also referred to as "HSP") consists of a dispersion term, a polar term and a hydrogen bond term. In the present specification, HSP is a value estimated from the literature value or the chemical structure of the compound by computer software (Hansen Solubility Parameter in Practice (HSPiP) version 4). The HSP of a mixture containing two or more compounds is calculated as the vector sum of the values obtained by multiplying the HSP of each compound by the volume ratio of each compound with respect to the entire mixture.

In the production method of the present invention, the number of carbon atoms is 3 to 7 in a reactor in which the temperature and pressure can be adjusted, and two adjacent carbon atoms have a hydrogen atom and a fluorine atom or a chlorine atom, respectively. Hydrofluorocarbons (HFCs) or hydrochlorofluorocarbons (HCFCs) having a bonded structure in the molecule are brought into contact with an alkaline aqueous solution in a liquid phase, and the HFCs or HCFCs are dechlorided or defluorinated to hydrofluoroolefins (hydrofluoroolefins). A method for producing a fluoroolefin, which comprises obtaining at least one fluoroolefin selected from HFO), perfluoroolefin (PFO), hydrochlorofluoroolefin (HCFO) and chlorofluoroolefin (CFO), wherein the temperature in the reactor is high. The production method is characterized in that the pressure is adjusted to a condition above the vapor pressure curve of the HFC or HCFC and below the vapor pressure curve of the fluoroolefin.

Specifically, the reaction to which the production method of the present invention is applied is the reaction represented by the following reaction formula (1). In the formula (1), the above-mentioned HFC or HCFC which is a starting material (raw material) is represented by the formula (A), and the target product which is HFO, PFO, HCFO or CFO is represented by the formula (B). The formula (C) is hydrogen chloride or hydrogen fluoride.

However, the symbols in the equation (1) are as follows.
One of X ¹ and X ² is a hydrogen atom, and the other is a fluorine atom or a chlorine atom.
Y ¹ and Y ² are independently hydrogen atoms, fluorine atoms, or chlorine atoms.
R ¹ and R ² are independently hydrogen atoms, fluorine atoms, chlorine atoms or aliphatic saturated hydrocarbon groups having 1 to 5 carbon atoms (however, some or all of the hydrogen atoms are chlorine atoms or fluorine atoms). The total number of carbon atoms of R ¹ and R ^{2 is 1 to 5.}
At ^{least one of Y 1} , Y ² , R ¹ and R ² is a fluorine atom.

Conventionally, when compound (A) is brought into contact with an alkaline aqueous solution in a liquid phase, hydrogen chloride or hydrogen fluoride is desorbed from compound (A) as shown in reaction (1) to obtain compound (B). Are known.

This reaction is usually carried out in a closed reactor with adjustable temperature and pressure. A liquid phase containing at least the compound (A) and an alkaline aqueous solution and a gas phase exist in the reactor, and the reaction (1) contains an organic phase mainly composed of the compound (A) and an alkaline aqueous solution in the liquid phase. It is carried out in a two-phase state of the main aqueous phase. Conventionally, in order to improve productivity, stirring conditions and equipment have been devised to efficiently perform two-phase contact, and a phase transfer catalyst has been used to promote the reaction. It was not easy to raise it and increase production efficiency.

In the above production method, the present inventor reduced the concentration of the compound (A) in the liquid phase as the reaction (1) proceeded in the reactor and the compound (B) was produced from the compound (A). Then, it was confirmed that the reaction rate was reduced. Then, by adjusting the temperature and pressure in the reactor to conditions above the vapor pressure curve of compound (A) and below the vapor pressure curve of compound (B), the reaction rate of reaction (1) can be adjusted. We have found that the compound (B) can be produced more efficiently by suppressing the decrease, and have completed the present invention.

In the reaction (1) to which the present invention is applied, the relationship between the molecular weights of the compound (A) and the compound (B) is such that the HCl or HF is removed from the compound (A), and the compound (B) is the compound (A). ) Is smaller in molecular weight. As a result, compound (B) usually has a higher vapor pressure and a lower boiling point than compound (A). Therefore, by adjusting the temperature and pressure in the reactor to be above the vapor pressure curve of compound (A) and below the vapor pressure curve of compound (B), the compound (A) in the liquid phase The decrease in the reaction rate is suppressed by suppressing the decrease in the concentration of. Hereinafter, the requirement of "adjusting the temperature and pressure in the reactor to be above the vapor pressure curve of compound (A) and below the vapor pressure curve of compound (B)" in the production method of the present invention is set forth. It is called requirement (II).

In the production method of the present invention, by satisfying the requirement (II), the mass [g] of the compound (A) in the liquid phase in the reactor is set to L _(A) , and the mass [g] of the compound (B) is set to L (A). The following formula (III) holds when the mass [g] of the compound (A) in the gas phase of _{L (B) is V (A)} and the mass [g] of the compound (B) is V _(B).
(V _(B) / V _(A) ) / (L _(B) / L _(A) )> 1 (III)

In the present invention, when the reaction (1) is carried out under the condition that the formula (III) is established, the decrease in the reaction rate is suppressed. The relationship of formula (III) is preferably maintained from the start to the end of the reaction. _{The value of the ratio of V (B)} / V _(A) to L _(B) / L _(A) shown on the left side of the formula (III) is preferably large, for example, 1.5 or more is preferable. 0 or more is more preferable.

In the production method of the present invention, the temperature and pressure inside the reactor may change as long as the above requirement (II) is satisfied, but the temperature and pressure are preferably kept constant within the range satisfying the requirement (II). It is preferably retained. Specifically, the pressure inside the reactor is preferably adjusted by discharging a predetermined amount of the gas phase to the outside of the reactor. In order to keep the pressure inside the reactor constant, it is preferable to continuously discharge the gas phase to the outside of the reactor. The specific temperature and pressure depend on the types of compound (A) and compound (B) in the reaction (1) to which the production method of the present invention described below can be applied.

The reaction in the present invention may be carried out by a batch type, a semi-continuous type or a continuous distribution type. In the production method of the present invention, when the gas phase is not discharged from the reactor during the reaction, the compound (B) is separated and recovered from the gas phase and the liquid phase in the reactor by a usual method after the reaction is completed. When the gas phase of the reactor is discharged from the reactor during the reaction, the compound (B) is separated and recovered from the discharged gas phase, and after the reaction is completed, the usual gas phase and liquid phase in the reactor are used. Compound (B) is separated and recovered by the method.

In the production method of the present invention, when the compound (B) is recovered from the reaction solution (liquid phase) after the reaction is completed, the reaction solution is left to be separated into an organic phase and an aqueous phase. In addition to the target product compound (B), the organic phase may contain unreacted compound (A), by-products and the like. When recovering compound (B) from the organic phase containing these, it is preferable to adopt a general separation and purification method by distillation or the like.

If unreacted compound (A) remains in the reaction solution, compound (A) can be concentrated by distillation and recycled as a raw material of the present invention. Further, the compound (A) may be recovered from the gas phase, and even in such a case, it can be recycled as a raw material of the present invention.

On the other hand, the aqueous phase separated from the organic phase can be reused by taking out this amount and adding a base again so as to have an appropriate concentration.

By separating, purifying and recovering the compound (B) obtained by the production method of the present invention as described above, a purified compound (B) containing the compound (B) with high purity can be obtained. If the purified compound (B) thus obtained contains acids such as HF and HCl and impurities such as water and oxygen, the equipment will corrode during its use, and the stability of the compound (B) will decrease. Etc. may occur. Therefore, it is preferable to remove these impurities by a conventionally known method to the extent that there is no problem in terms of corrosion and stability.

(Reaction to which the production method of the present invention can be applied)
Specific examples of reactions to which the production method of the present invention can be applied will be described below. As an example in the case of 3 carbon atoms, a production example of fluoropropene represented by the following reactions of formulas (1-1) to (12-2), formulas (15-1) and formulas (15-2). Can be mentioned. As an example in the case of 4 carbon atoms, there is an example of producing fluorobutene shown in the reactions of the following formulas (13-1) and (13-2). As an example in the case of 5 carbon atoms, there is an example of producing fluoropentene shown in the reactions of the following formulas (14-1) and (14-2).

Formula (1-1) is 3,3-dichloro-1,1,1,2,2-pentafluoropropane (HCFC-225ca) and / or 1,1-dichloro-1,2,3,3,3- It is a reaction formula which obtains 1,1-dichloro-2,3,3,3-tetrafluoropropene (CFO-1214ya) by de-HF from pentafluoropropane (HCFC-225ea). Formula (1-2) is 2,3,3-trichloro-1,1,1,2-tetrafluoropropane (HCFC-224ba) and / or 1,1,1-trichloro-2,3,3,3- It is a reaction formula to obtain CFO-1214ya by dehydrochloric acid from tetrafluoropropane (HCFC-224eb).

Formula (2-1) is 1,1,1,2,2,3,3-heptafluoropropane (HFC-227ca) and / or 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ca). It is a reaction formula to obtain hexafluoropropene (PFO-1216) by de-HF from HFC-227ea). Formula (2-2) is 2-chloro-1,1,1,2,3,3-hexafluoropropane (HCFC-226ba) and / or 1-chloro-1,1,2,3,3,3- It is a reaction formula to obtain PFO-1216 by dehydrochloric acid from hexafluoropropane (HCFC-226ea).

Formula (3-1) is 3-chloro-1,1,1,2,2-pentafluoropropane (HCFC-235cc) and / or 3-chloro-1,1,1,2,3-pentafluoropropane (CHFC-235cc). HCFC-235ea) by de-HF (Z) -1-chloro-2,3,3,3-tetrafluoropropene (HCFO-1224yd (Z)) and / or (E) -1-chloro-2,3 It is a reaction formula for obtaining 3,3-tetrafluoropropene (HCFO-1224yd (E)). Formula (3-2) formulates 2,3-dichloro-1,1,1,2-tetrafluoropropane (HCFC-234bb) and / or 3,3-dichloro-1,1,1,2-tetrafluoropropane (2,3-dichloro-1,1,1,2-tetrafluoropropane). It is a reaction formula to obtain HCFO-1224yd (Z) and / or HCFO-1224yd (E) by deHCl from HCFC-234ea).

Formula (4-1) is 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb) and / or 2-chloro-1,1,1,3-tetrafluoropropane (HCFC-244db). This is a reaction formula for obtaining 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) from HF. Formula (4-2) is 2,2-dichloro-1,1,1-trifluoropropane (HCFC-243xb) and / or 2,3-dichloro-1,1,1-trifluoropropane (HCFC-243db). It is a reaction formula to obtain HCFO-1233xf by dehydrochloric acid from.

Formula (5-1) is 3-chloro-1,1,2,2-tetrafluoropropane (HCFC-244ca) and / or 1-chloro-1,2,3,3-tetrafluoropropane (HCFC-244ea). By de-HF from (Z) -1-chloro-2,3,3-trifluoropropene (HCFO-1233yd (Z)) and / or (E) -1-chloro-2,3,3-trifluoropropene ( This is a reaction formula for obtaining HCFO-1233yd (E)). Formula (5-2) formulates 2,3-dichloro-1,1,2-trifluoropropane (HCFC-243ba) and / or 1,1-dichloro-2,3,3-trifluoropropane (HCFC-243eb). It is a reaction formula to obtain HCFO-1233yd (Z) and / or HCFO-1233yd (E) by deHCl from.

Formula (6-1) is 3-chloro-1,1,1,2-tetrafluoropropane (HCFC-244eb) and / or 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244fa). By de-HF from (Z) -1-chloro-3,3,3-trifluoropropene (HCFO-1233zd (Z)) and / or (E) -1-chloro-3,3,3-trifluoropropene ( This is a reaction formula for obtaining HCFO-1233zd (E)). Formula (6-2) is 2,3-dichloro-1,1,1-trifluoropropane (HCFC-243db) and / or 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243fa). It is a reaction formula to obtain HCFO-1233zd (Z) and / or HCFO-1233zd (E) by dehydrochloric acid from.

Formula (7-1) is derived from 1,1,1,2,2-pentafluoropropane (HFC-245cc) and / or 1,1,1,2,3-pentafluoropropane (HFC-245eb) by de-HF. It is a reaction formula for obtaining 2,3,3,3-tetrafluoropropene (HFO-1234yf). Formula (7-2) is 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb) and / or 3-chloro-1,1,1,2-tetrafluoropropane (HCFC-244eb). It is a reaction formula to obtain HFO-1234yf by dehydrochloric acid from.

Formula (8-1) is derived from 1,1,1,2,3-pentafluoropropane (HFC-245eb) and / or 1,1,1,3,3-pentafluoropropane (HFC-245fa) by de-HF. (Z) -1,3,3,3-tetrafluoropropene (HFO-1234ze (Z)) and / or (E) -1,3,3,3-tetrafluoropropene (HFO-1234ze (E)) It is a reaction formula to obtain. Formula (8-2) is 2-chloro-1,1,1,3-tetrafluoropropane (HCFC-244db) and / or 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244fa). It is a reaction formula to obtain HFO-1234ze (Z) and / or HFO-1234ze (E) by dehydrochloric acid from.

Formula (9-1) formulates 2,3-dichloro-1,1,1,2-tetrafluoropropane (HCFC-234bb) and / or 2,3-dichloro-1,1,1,3-tetrafluoropropane (). De-HF from HCFC-234da) (Z) -1,2-dichloro-3,3,3-trifluoropropene (HCFO-1223xd (Z)) and / or (E) -1,2-dichloro-3, It is a reaction formula for obtaining 3,3-trifluoropropene (HCFO-1223xd (E)). Formula (9-2) formulates 2,2,3-trichloro-1,1,1-trifluoropropane (HCFC-233ab) and / or 2,3,3-trichloro-1,1,1-trifluoropropane (2,3,3-trichloro-1,1,1-trifluoropropane). It is a reaction formula to obtain HCFO-1223xd (Z) and / or HCFO-1223xd (E) by dehydrochloric acid from HCFC-233da).

Formula (10-1) formulates 1,1,1,2,2,3-hexafluoropropane (HFC-236cc) and / or 1,1,1,2,3,3-hexafluoropropane (HFC-236eb). By de-HF from (Z) -1,2,3,3,3-pentafluoropropene (HFO-1225ye (Z)) and / or (E) -1,2,3,3,3-pentafluoropropene ( It is a reaction formula for obtaining HFO-1225ye (E)). Formula (10-2) formulates 2-chloro-1,1,1,2,3-pentafluoropropane (HCFC-235bb) and / or 3-chloro-1,1,1,2,3-pentafluoropropane (HCFC-235bb). It is a reaction formula to obtain HFO-1225ye (Z) and / or HFO-1225ye (E) by dehydrochlorination from HCFC-235ea).

Equation (11-1) is expressed as 3,3,3 by de-HF from 1,1,1,2-tetrafluoropropane (HFC-254eb) and / or 1,1,1,3-tetrafluoropropane (HFC-254fb). This is a reaction formula for obtaining 3-trifluoropropene (HFO-1243zf). Formula (11-2) is dehydrochlorinated from 2-chloro-1,1,1-trifluoropropane (HCFC-253db) and / or 3-chloro-1,1,1-trifluoropropane (HCFC-244eb). It is a reaction formula to obtain HFO-1243zf.

Formula (12-1) is derived from 1,1,2-trifluoropropane (HFC-263eb) and / or 1,1,3-trifluoropropane (HFC-263fa) by de-HF to 3,3-difluoropropene (HFO). It is a reaction formula for obtaining −1252 zf). Formula (12-2) is a reaction to obtain HFO-1252zf by dehydrochlorination from 2-chloro-1,1-difluoropropane (HCFC-262db) and / or 3-chloro-1,1-difluoropropane (HCFC-262fa). It is an expression.

Equation (13-1) is expressed by removing HF from 1,1,1,2,4,5,4-heptafluorobutane (HFC-347mef) (Z) -1,1,1,4,4-4. Reaction to obtain hexafluoro-2-butane (HFO-1336 mzz (Z)) and / or (E) -1,1,1,4,4,4-hexafluoro-2-butene (HFO-1336 mzz (E)) It is an expression. Formula (13-2) gives HFO-1336 mzz (Z) or HFO-1336 mzz (E) by dehydrochlorination from 2-chloro-1,1,1,4,4,4-hexafluorobutane (HCFC-346 mdf). It is a reaction formula.

Formula (14-1) is 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane (HCFC-448occc) and / or 5-chloro-1,1,2,2. De-HF from 3,3,4,5-octafluoropentane (HCFC-448pcs) to (Z) -1-chloro-2,3,3,4,5,5-heptafluoro-1-pentene (HCFO) In the reaction formula to obtain -1437 dycc (Z)) and / or (E) -1-chloro-2,3,3,4,5,5-heptafluoro-1-pentene (HCFO-1437 dycc (E)). be. Formula (14-2) formulates 4,5-dichloro-1,1,2,2,3,3,4-heptafluoropentane (HCFC-447obcc) and / or 5,5-dichloro-1,1,2, This is a reaction formula for obtaining HCFO-1437 dycc (Z) and / or HCFO-1437 dycc (E) by deHCl from 2,3,3,4-heptafluoropentane (HCFC-447necc).

Formula (15-1) is 3-chloro-1,1,1,2,2,3-hexafluoropropane (HCFC-226ca) and / or 1-chloro-1,1,2,3,3,3- De-HF from hexafluoropropane (HCFC-226ea) to (Z) -1-chloro-1,2,3,3,3-pentafluoropropene (CFO-1215yb (Z)) and / or (E) -1- It is a reaction formula for obtaining chloro-1,2,3,3,3-pentafluoropropene (CFO-1215yb (E)). Formula (15-2) formulates 2,3-dichloro-1,1,1,2,3-pentafluoropropane (HCFC-225ba) and / or 1,1-dichloro-1,2,3,3,3- It is a reaction formula for obtaining CFO-1215yb (Z) and / or CFO-1215yb (E) by deHCl from pentafluoropropane (HCFC-225eb).

In each of the above reactions, as a reaction in which the production method of the present invention is particularly preferably used, a reaction for obtaining tetrafluoropropene by deHCl from monochlorotetrafluoropropane from the viewpoint that the reaction rate can be improved and the reaction can be carried out efficiently. A reaction for obtaining monochlorotetrafluoropropene by deHCl from dichlorotetrafluoropropane can be mentioned.

The reaction for obtaining tetrafluoropropene from monochlorotetrafluoropropane by dehydrochloric acid is a reaction for obtaining 1234yf by dehydrochlorination from 244bb and / or 244eb of formula (7-2), 244db and / or 244fa of formula (8-2). The reaction of obtaining 1234ze (Z) and / or 1234ze (E) by dehydrochloric acid from the above can be mentioned, and the reaction of obtaining 1234yf by dehydrochloric acid from 244bb and / or 244eb of the formula (7-2) can be more preferably mentioned.

Examples of the reaction for obtaining monochlorotetrafluoropropene from dichlorotetrafluoropropane by dealkylation include a reaction for obtaining 1224yd (Z) and / or 1224yd (E) from dichlorotetrafluoropropane by deHCl from 234bb and / or 234ea of the formula (3-2). Be done.

In the above reaction, the effect of the present invention is particularly large when the raw material contains a compound having _{3 CH groups such as 244 bb and H is required to be eliminated from the 3 CH groups of the compound.} Therefore, a high effect can be expected in the reaction of obtaining 1234yf by deHCl from 244bb.

In the reaction (1) according to the production method of the present invention, the compound (A) is in a liquid phase as an organic phase and is in physical contact with an aqueous alkaline solution, more specifically, by contacting with a base in the aqueous alkaline solution. , De-HF or de-HCl reaction occurs to produce compound (B).

The method for obtaining compound (A) is not particularly limited. It may be produced by a known method, or a commercially available product may be used. For example, 244bb and / or 244eb in the reaction (7-2) to which the present invention is preferably applied can be produced, for example, by a chlorination reaction in which 254eb is reacted with chlorine. Further, 234bb and / or 234ea in the reaction (3-2) can be produced, for example, by further chlorinating the obtained 244bb and / or 244ea in the chlorination reaction of 254eb.

In the production method of the present invention, the compound (A) may be introduced into the reactor in the form of a mixture containing the compound (A) and impurities. The amount of impurities in the mixture shall not affect the effect of the production method of the present invention. Specifically, compound (A) may be used together with by-products and unreacted raw materials that are by-produced during the production of compound (A). For example, the composition of the compound (A) having a purity of 85% by mass or more, preferably 90% by mass or more, particularly preferably 95% by mass or more can be used in the production method of the present invention.

The alkaline aqueous solution used in the production method of the present invention means an aqueous solution in which a base is dissolved in water. The base is not particularly limited as long as the base can carry out the above reaction (1). The base preferably contains at least one selected from the group consisting of metal hydroxides, metal oxides and metal carbonates.

When the base is a metal hydroxide, examples thereof include alkaline earth metal hydroxide and alkali metal hydroxide. Examples of the alkaline earth metal hydroxide include magnesium hydroxide, calcium hydroxide, strontium hydroxide, and barium hydroxide. Examples of the alkali metal hydroxide include lithium hydroxide, sodium hydroxide, and potassium hydroxide.

When the base is a metal oxide, examples of the metal constituting the metal oxide include alkali metal elements, alkaline earth metal elements, transition metal elements, Group 12 metal elements, and Group 13 metal elements. Among them, alkali metal elements, alkaline earth metal elements, group 6 metal elements, group 8 metal elements, group 10 metal elements, group 12 metal elements, and group 13 metal elements are preferable, and sodium, calcium, chromium, and so on. Iron, zinc and aluminum are more preferred.

The metal oxide may be an oxide containing one kind of metal, or may be a composite oxide of two or more kinds of metals. As the metal oxide, sodium oxide, calcium oxide, chromium oxide (chromia), aluminum oxide (alumina), zinc oxide and the like are preferable, and alumina and chromaa are more preferable, from the viewpoint of reaction time and reaction yield.

When the base is a metal carbonate, examples thereof include alkaline earth metal carbonate and alkali metal carbonate. Examples of the alkaline earth metal carbonate include metal carbonates such as beryllium, magnesium, calcium, strontium, barium, and radium. Examples of the alkali metal carbonate include carbonates of metals such as lithium, sodium, potassium, rubidium, cesium, and francium.

As the base used in the production method of the present invention, a metal hydroxide is preferable from the viewpoint of reaction time and reaction yield, and at least one selected from the group consisting of potassium hydroxide and sodium hydroxide is particularly preferable. One type of metal hydroxide may be used alone, or two or more types may be used in combination.

The content of the base in the alkaline aqueous solution is preferably such that the ratio (unit%) of the mass of the base to the total amount (mass) of the alkaline aqueous solution is 0.5 to 48% by mass, from the viewpoint of the reaction rate. % Is more preferred, and 30-40% by mass is even more preferred. If the amount of base is less than the above range, a sufficient reaction rate may not be obtained. On the other hand, if the amount of base exceeds the above range, the amount of by-products produced may increase and the selectivity of the target substance (compound (B)) may decrease.

The amount of the base used in the production method of the present invention depends on the type of reaction (1). For example, in the reaction to obtain 1234yf from 244bb and / or 244eb by deHCl, the amount of base per mole of 244bb and / or 244eb is from the viewpoint of improving the conversion of 244bb and / or 244eb and the selectivity of 1234yf. , 0.2-3.0 mol, more preferably 0.5-2.5 mol.

Also, for example, in a reaction to obtain 1224 yd (Z) and / or 1224 yd (E) from 234 bb and / or 234 ea by deHCl, the conversion rate of 234 bb and / or 234 ea and 1224 yd (Z) and / or 1224 yd (E). From the viewpoint of improving the selectivity of 234 bb and / or 234 ea, the amount of the base per 1 mol is preferably 0.2 to 3.0 mol, more preferably 0.5 to 2.5 mol.

In the production method of the present invention, preferable temperature and pressure conditions within the conditions satisfying the requirement (II) depend on the types of the compound (A) and the compound (B). Preferred temperature and pressure conditions in the production method of the present invention will be described below by exemplifying a reaction of obtaining 1234 yd from 244 bb by deHCl and a reaction of obtaining 1224 yd from 234 bb by deHCl.

FIG. 1 shows the vapor pressure curves of 244bb and 1234yf. In FIG. 1, the solid line shows the vapor pressure curve of 244 bb, and the broken line shows the vapor pressure curve of 1234 yf. In each compound, the compound is a gas phase under temperature and pressure conditions below the vapor pressure curve, and the compound is a liquid phase under temperature and pressure conditions above the vapor pressure curve. Therefore, in FIG. 1, in the temperature and pressure region surrounded by the vapor pressure curve of 244bb and the vapor pressure curve of 1234yf, it can be seen that 44bb is the liquid phase and 1234yf is the gas phase.

Here, in the reaction of obtaining 1234yf from 244bb by dehydrochloric acid, the reaction temperature is preferably 60 to 120 ° C., preferably 70 to 115 ° C. from the viewpoint of improving the reaction rate and the reaction rate and easily suppressing by-products. , 70-110 ° C. is more preferable. As described above, the pressure in the reactor is set to be equal to or higher than the vapor pressure of 244 bb at the reaction temperature and lower than or equal to the vapor pressure of 1234 yf. Further, the pressure is preferably 2.0 MPaG or less in terms of the design of the reactor. Therefore, it is preferable to carry out the reaction within the range satisfying these conditions.

FIG. 2 shows the vapor pressure curves of 234 bb, 1224 yd (Z) and 1224 yd (E). In FIG. 2, the solid line shows the vapor pressure curve of 234 bb, the broken line shows the vapor pressure curve of 1224 yd (Z), and the dotted line shows the vapor pressure curve of 1224 yd (E). In each compound, the compound is a gas phase under temperature and pressure conditions below the vapor pressure curve, and the compound is a liquid phase under temperature and pressure conditions above the vapor pressure curve. Therefore, in FIG. 2, in the temperature and pressure region surrounded by the vapor pressure curve of 234 bb and the vapor pressure curve of 1224 yd (E), 234 bb is the liquid phase and 1224 yd (Z) and 1224 yd (E) are the gas phases. It turns out that there is.

Here, in the reaction for obtaining 1224 yd from 234 bb by dehydrochloric acid, the reaction temperature is preferably 10 to 90 ° C., more preferably 20 to 80 ° C. from the viewpoint of improving the reaction rate and the reaction rate and easily suppressing by-products. preferable. As described above, the pressure in the reactor is set to be equal to or higher than the vapor pressure of 234 bb at the reaction temperature and lower than or equal to the vapor pressure of 1224 yd. Further, the pressure is preferably 0.5 MPaG or less in terms of the design of the reactor. Therefore, it is preferable to carry out the reaction within the range satisfying these conditions.

Two examples of the reaction of obtaining 1234yf from 244bb by deHCl and the reaction of obtaining 1224yd from 234bb by deHCl have been described with reference to FIGS. 1 and 2. From the vapor pressure curves of A) and compound (B) and the preferable reaction temperature and reaction pressure, the preferable temperature and pressure ranges in the production method of the present invention can be set.

In the production method of the present invention, the reaction solution is composed of an organic phase mainly composed of compound (A) and an aqueous phase composed of an alkaline aqueous solution. In the production method of the present invention, for the purpose of further promoting the reaction, another substance that does not impair the effect of the present invention may be present in the reaction system, and for example, a phase transfer catalyst is preferably present. The phase transfer catalyst is present in both the organic phase and the alkaline aqueous solution, and promotes the dehalogenation reaction of the compound (A) by contact with the alkaline aqueous solution.

Examples of the phase transfer catalyst include quaternary ammonium salts, quaternary phosphonium salts, quaternary ammonium salts, sulfonium salts, crown ethers, etc., which are quaternary in terms of industrial availability, price, and ease of handling. Ammonium salts are preferred.

Specifically, as the quaternary ammonium salt, tetra-n-butylammonium chloride (TBAC), tetra-n-butylammonium bromide (TBAB), methyltri-n-octylammonium chloride (TOMAC) and the like are preferable. Of these, tetra-n-butylammonium chloride (TBAC) and tetra-n-butylammonium bromide (TBAB) are preferable from the viewpoint of further promoting the reaction, and tetra-n-butylammonium bromide (TBAB) is preferable from the viewpoint of availability. ) Is more preferable, and tetra-n-butylammonium chloride (TBAC) is more preferable from the viewpoint of reactivity.

When a phase transfer catalyst is used in the production method of the present invention, the amount thereof is preferably 0.001 to 10 parts by mass, more preferably 0.01 to 5 parts by mass, based on 100 parts by mass of compound (A). 0.01 to 3 parts by mass is more preferable. If the amount of the phase transfer catalyst is too small, a sufficient reaction rate may not be obtained, and even if a large amount is used, the reaction promoting effect according to the amount used cannot be obtained, which is disadvantageous in terms of cost.

In the production method of the present invention, the reaction solution may contain a water-soluble organic solvent (hereinafter, referred to as “water-soluble organic solvent (S)”) capable of dissolving the compound (A) together with the phase transfer catalyst. The water-soluble organic solvent (S) is water-soluble and can dissolve the compound (A).

In the present specification, the water solubility in the water-soluble organic solvent (S) means that when the water-soluble organic solvent (S) and pure water are mixed at an arbitrary mixing ratio at 25 ° C., no phase separation or turbidity occurs. The property of uniformly dissolving. Further, the fact that the water-soluble organic solvent (S) can dissolve the compound (A) means that the amount of the water-soluble organic solvent (S) is 20% by mass based on the compound (A) at 25 ° C. It refers to the property of uniformly dissolving A) and the water-soluble organic solvent (S) without causing phase separation or turbidity when mixed.

The water-soluble organic solvent (S) is present in both the organic phase and the alkaline aqueous solution as in the phase transfer catalyst, and has a function of further enhancing the action of promoting the dehalogenation reaction of the compound (A) in the phase transfer catalyst. Have.

As the water-soluble organic solvent (S), for example, a compound capable of dissolving the compound (A) from water-soluble alcohols, ketones, ethers, esters and the like is appropriately selected and used according to the type of the compound (A). ..

Examples of water-soluble alcohols include methanol, ethanol, propane-1-ol, butane-1-ol, propane-2-ol, butane-2-ol, 2-methylpropan-2-ol, and 2-methylbutane-. Examples of the water-soluble ketone such as 2-ol include acetone, methyl ethyl ketone, diethyl ketone, methyl propyl ketone, methyl isobutyl ketone, methyl amyl ketone, cyclohexanone and the like. Examples of the water-soluble ether include chain ethers such as tetraethylene glycol dimethyl ether (hereinafter, also referred to as "tetraglime"), dimethyl ether, ethyl methyl ether, diethyl ether and ethylene oxide, and cyclic ethers such as tetrahydrofuran, furan and crown ethers. However, examples of the water-soluble ester include methyl acetate and methyl formate.

The water-soluble organic solvent (S) has a property of dissolving the compound (A) in addition to being water-soluble. The water-soluble organic solvent (S) is represented by the following formula (I) based on the Hansen solubility parameter from the viewpoint of further enhancing the action of the phase transfer catalyst in the dehalogenation reaction of the compound (A). The interaction distance (Ra) between the compound (A) and the compound (A) is preferably 25.0 or less, and more preferably 23.0 or less.
_{Ra = [4 × (δD 1} -δD 2) 2 + (δP 1 -δP 2) 2 + (δH 1 -δH 2) 2] 0.5 (I)

Each formula _{(I), δD 1, δP} 1 and delta] H ₁ is the Hansen solubility parameter of the water-soluble organic solvent (S), dispersion term, the polarity term and hydrogen bond, [delta] D _2, [delta] P ₂ and delta] H ₂ is Each indicates the dispersion term, the polarity term and the hydrogen bond term in the Hansen solubility parameter of the compound (A), and the unit is (MPa) ^1/2 .

Specifically, for example, when 244bb, 244eb, 234bb, and 234ea are used as the compound (A), the interaction distance (Ra) of each compound preferable as the water-soluble organic solvent (S) with respect to these compounds (A). ) Is shown in Table 1.

As shown in Table 1, methanol, acetone, tetraglyme and tetrahydrofuran have an interaction distance (Ra) of 25.0 or less with any of 244bb, 244eb, 234bb and 234ea, and are used in these dehalogenation reactions. It can be preferably used as a water-soluble organic solvent (S).

Similarly, a preferable combination of the compound (A) and the water-soluble organic solvent (S) other than those shown in Table 1 can be selected using the interaction distance (Ra) as an index.

The amount of the water-soluble organic solvent (S) used in the production method of the present invention is preferably 1 to 100 parts by mass, more preferably 3 to 80 parts by mass, and 5 to 60 parts by mass with respect to 100 parts by mass of the compound (A). Parts by mass are even more preferred. If the amount of the water-soluble organic solvent (S) is too small, a sufficient reaction rate may not be obtained, and even if a large amount is used, a reaction promoting effect according to the amount used cannot be obtained, resulting in cost and volumetric efficiency. It is disadvantageous in terms of.

In the production method of the present invention, from the viewpoint of industrially producing a target fluoroolefin in large quantities, a stirring blade is installed in a batch type, semi-continuous type or continuous type reactor, and the mixture is produced by stirring the stirring blade. Is preferable. An example of a reaction apparatus to which the production method of the present invention can be applied will be described below with reference to the drawings. FIG. 3 shows a schematic view of an example of a reaction apparatus used in the method for producing a fluoroolefin of the present invention.

The reactor shown in FIG. 3 is an example, and the reactor used in the embodiment of the present invention is not limited to such a structure. Each member can be modified, deleted, or changed as needed, and other members can be added.

The reactor 100 has a reactor body 1, a lid 2, a stirrer 7 having a stirring blade, and a reactor 20 having a thermocouple 8 installed in a constant temperature bath 5 provided with a heater 6. The reaction apparatus 100 has a compound (A) accommodating tank 3 accommodating the compound (A) and an alkaline aqueous solution accommodating tank 4 accommodating the compound (A) outside the constant temperature bath 5, and reacts from each tank via a supply line 21. A predetermined amount of the compound (A) and the alkaline aqueous solution are supplied as a liquid phase in the vessel 20 leaving a space constituting the gas phase.

The inside of the reactor 20 is composed of a liquid phase L and a gas phase V, and the temperature and pressure inside the reactor 20 are adjusted to carry out the reaction (1) under the condition that the formula (II) is established. Under these conditions, the pressure in the reactor 20 rises as the reaction (1) progresses. Therefore, in order to suppress this and keep the pressure in the reactor 20 within a predetermined range, the air in the reactor 20 is maintained. A part of the phase V is collected in the recovery tank 10 via the discharge line 22.

The reaction device 100 has a configuration in which a back pressure valve 9 is provided in the middle of the discharge line 22. By using the back pressure valve 9, the pressure in the reactor 20 is kept constant, and the gas phase V is continuously discharged from the reactor 20. That is, the reaction device 100 is a reaction device capable of more effectively carrying out the production method of the present invention.

In addition, in order to facilitate the recovery of the compound (B) in the reactor 100, in order to recover the compound (A) in the gas phase discharged from the reactor 20 between the reactor 20 and the back pressure valve 9. A withstand voltage capacitor or the like may be provided. As a result, the composition having an increased content of the compound (B) can be recovered in the recovery tank 10.

The material of the constituent members constituting the reaction device 100 is a compound (A), an aqueous alkaline solution, a reaction product containing the compound (B), an optionally used phase transfer catalyst, and a water-soluble organic solvent (S). The material is not particularly limited as long as it is a material that is inactive to the components of the reaction solution contained and has corrosion resistance. For example, alloys such as glass, iron, nickel, and stainless steel containing iron as a main component can be mentioned.

According to the production method of the present invention, the reaction is carried out in a production method in which compound (A) is brought into contact with an alkaline aqueous solution in a liquid phase in a reactor in which temperature and pressure can be adjusted to obtain compound (B) by dehydrohalation. More efficiently by adjusting the temperature and pressure in the reactor so that the relationship between the abundance of the compound (A) and the compound (B) in the liquid phase and the gas phase in the vessel satisfies the formula (II). Compound (B) can be produced. Further, since the production method of the present invention is carried out by a liquid phase reaction, a reactor smaller than that of a gas phase reaction can be adopted, which is industrially advantageous.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited to these Examples. In Examples 1 to 4, 1234yf was prepared by deHCl using 244bb as compound (A). In Examples 5-8, 1224 yd was prepared by deHCl using 234 bb as compound (A). Examples 1, 2 and 5 and 6 are examples, and examples 3 and 4 and examples 7 and 8 are comparative examples.

[Conditions for gas chromatography]
In the production of the following various compounds, the composition analysis of the obtained reaction composition was performed using gas chromatography (GC). As the column, DB-1301 (trade name, manufactured by Agilent Technologies, Ltd., length 60 m × inner diameter 250 μm × thickness 1 μm) was used.

[Manufacturing example of 244bb]
254 eb was chlorinated as follows to produce 244 bb and 244 eb. First, a stainless steel autoclave (internal volume 6.9 liters) equipped with a quartz tube and a jacket that transmit light from a light source was cooled to 20 ° C. _{After putting 2336 g of carbon tetrachloride (CCl 4} ) and 103 g of 254 eb into this autoclave (hereinafter referred to as a reactor), it is visible from an LED lamp (LHT42N-G-E39 manufactured by Mitsubishi Electric Corporation, output 40 W). Chlorine gas was introduced into the reactor at a flow rate of 3.2 g / min while irradiating with light. As the reaction progressed, heat of reaction was generated, and the temperature inside the reactor rose to 23.8 ° C. The above flow rate chlorine gas was introduced for 2 minutes, that is, 0.10 mol of chlorine was introduced with respect to 1 mol of 254 eb, and light irradiation was continued until the temperature in the reactor became constant at 20 ° C. The pressure in the reactor was 0.045 MPa before chlorine supply and 0.045 MPa after chlorine supply, that is, the reaction pressure.

After completion of the reaction, the obtained reaction solution was mixed with a 20% by mass aqueous solution of potassium hydrogen carbonate to neutralize, and then a liquid separation operation was performed. After standing, the reaction composition was recovered from the separated lower layer and distilled to obtain 244 bb.

[Example 1]
A reactor similar to that shown in FIG. 3 was used. A 0.1 L reactor equipped with a thermocouple and a stirring blade was installed in a constant temperature bath and kept at 80 ° C. In this reactor, 588.8 g of a 25 mass% NaOH aqueous solution and 277.0 g of the 244 bb obtained above (the molar ratio of NaOH to 244 bb is NaOH: 244 bb = 2: 1), as a phase transfer catalyst. 8.3 g of tetra-n-butylammonium bromide (TBAB) was added, and the reactor was closed.

The stirring blade was rotated at 600 rpm, the back pressure valve was set so that the pressure in the reactor was 0.8 MPaG, and the reaction was carried out for 4 hours while discharging the gas phase from the reactor. The gas phase discharged from the reactor was collected in a recovery tank. After completion of the reaction, the reactor was taken out from the constant temperature bath and cooled to 0 ° C. with ice water to stop the reaction, and the reaction composition was recovered. The reaction composition recovered from the reactor and the gas phase (reaction composition) recovered in the recovery tank were subjected to GC analysis to determine the conversion rate of 244bb and the selectivity of 1234yf. The conversion of 244bb was 34.3%, the yield of 1234yf was 34.3%, and the selectivity was 100%.

[Example 2]
In Example 1, the reaction was carried out in the same manner except that the reaction time was changed to 16 hours. As a result, the conversion rate of 244bb was 62.7%, the yield of 1234yf was 62.7%, and the selectivity was 100%.

[Example 3]
In Example 1, a 4-hour 244bb deHCl reaction was carried out in the same manner except that the gas phase was not discharged from the reactor. When the pressure in the reactor during the reaction was specified, it was 2.1 MPaG, which was in the upper region of the vapor pressure curve of 1234yf in FIG. After completion of the reaction, GC analysis of the recovered reaction composition was carried out to determine the conversion rate of 244bb and the selectivity of 1234yf. The conversion of 244bb was 29.1%, the yield of 1234yf was 29.1%, and the selectivity was 100%.

[Example 4]
In Example 3, the reaction was carried out in the same manner except that the reaction time was changed to 16 hours. As a result, the conversion rate of 244bb was 51.3%, the yield of 1234yf was 51.3%, and the selectivity was 100%.

[Manufacturing example of 234bb]
1234yf was chlorinated as follows to produce 234bb.

First, a stainless steel reactor (internal volume 2.3 liters) equipped with a quartz tube and a jacket that transmit light from a light source was cooled to 0 ° C. After adding 1395 g of carbon tetrachloride (CCl ₄ ) as a solvent into this reactor, a flow rate of 1234 yf at 245 g / h while irradiating visible light from a fluorescent lamp (Neocompact EFP12EL manufactured by Toshiba Corporation, output 12 W). Then, chlorine gas was supplied into the reactor at a flow rate of 152 g / h.

As the reaction progressed, heat of reaction was generated, the temperature inside the reactor rose to 7.6 ° C, and the pressure inside the reactor rose to 0.08 MPaG. The reaction was continued for 1 hour while supplying 1234yf and chlorine gas at the above flow rates, and after confirming that 245 g of 1234yf and 152 g of chlorine were supplied, the supply of 1234yf and chlorine was stopped, and the pressure in the reactor was increased. Light irradiation was continued until the pressure became normal. After completion of the reaction, the obtained reaction solution was neutralized with a 20% by mass potassium hydrogen carbonate aqueous solution, and then a liquid separation operation was performed. After standing, 1734 g of product (1) was recovered from the separated lower layer. The product (1) was distilled by a normal operation to obtain 234 bb having a purity of 99.8%.

After completion of the reaction, the obtained reaction solution was mixed with a 20% by mass aqueous solution of potassium hydrogen carbonate to neutralize, and then a liquid separation operation was performed. After standing, the reaction composition was recovered from the separated lower layer and distilled to obtain 234 bb.

[Example 5]
A reactor similar to that shown in FIG. 3 was used. A 0.1 L reactor equipped with a thermocouple and a stirring blade was installed in a constant temperature bath and kept at 30 ° C. In this reactor, 478.5 g of a 20 mass% NaOH aqueous solution and 276.6 g of the 234 bb obtained above (the molar ratio of NaOH to 234 bb is NaOH: 234 bb = 2: 1), as a phase transfer catalyst. 1.4 g of tetra-n-butylammonium bromide (TBAB) was added, and the reactor was closed.

The stirring blade was rotated at 600 rpm, the back pressure valve was set so that the pressure in the reactor was 0 MPaG, and the reaction was carried out for 1 hour while discharging the gas phase from the reactor. The gas phase discharged from the reactor was collected in a recovery tank. After completion of the reaction, the reactor was taken out from the constant temperature bath and cooled to 0 ° C. with ice water to stop the reaction, and the reaction composition was recovered. The reaction composition recovered from the reactor and the gas phase (reaction composition) recovered in the recovery tank were subjected to GC analysis to determine the conversion rate of 234 bb and the selectivity of 1224 yd. The conversion of 234bb was 54.1%, the yield of 1224yd was 54.1%, and the selectivity was 100%.

The obtained 1224 yd was a mixture of 1224 yd (Z) and 1224 yd (E). As shown in FIG. 2, in this example, the reaction was carried out in a region higher than the vapor pressure curve of 234 bb and lower than the vapor pressure curve of either 1224 yd (Z) or 1224 yd (E). The conversion rate of 1224yd shown above is the sum of the conversion rates of 1224yd (Z) and 1224yd (E).

[Example 6]
In Example 5, the reaction was carried out in the same manner except that the reaction time was changed to 2 hours. As a result, the conversion rate of 234bb was 63.4%, the yield of 1224yd was 63.4%, and the selectivity was 100%.

[Example 7]
In Example 5, the dehydrochloric acid reaction of 234 bb for 1 hour was carried out in the same manner except that the gas phase was not discharged from the reactor. When the pressure in the reactor during the reaction was specified, it was 0.15 MPaG, which was in the upper region of the vapor pressure curve of 1224 yd (Z) in FIG. After completion of the reaction, GC analysis of the recovered reaction composition was performed to determine the conversion rate of 234 bb and the selectivity of 1224 yd. The conversion of 234bb was 50.5%, the yield of 1224yd was 50.5%, and the selectivity was 100%.

[Example 8]
In Example 7, the reaction was carried out in the same manner except that the reaction time was changed to 2 hours. As a result, the conversion rate of 234bb was 58.2%, the yield of 1224yd was 58.2%, and the selectivity was 100%.

Claims (8)

In a reactor in which the temperature and pressure can be adjusted, a structure in which the number of carbon atoms is 3 to 7 and a hydrogen atom and a fluorine atom or a chlorine atom are bonded to two adjacent carbon atoms, respectively, is formed in the molecule. The hydrofluorocarbon or hydrochlorofluorocarbon to have is brought into contact with an alkaline aqueous solution in a liquid phase, and the hydrofluorocarbon or hydrochlorofluorocarbon is dechlorinated or defluorinated by hydrogen to hydrofluoroolefin, perfluoroolefin, hydrochlorofluoroolefin and chlorofluoro. A method for producing a fluoroolefin, which obtains at least one fluoroolefin selected from olefins.
A production method for adjusting the temperature and pressure in the reactor to conditions above the vapor pressure curve of the hydrofluorocarbon or hydrochlorofluorocarbon and below the vapor pressure curve of the fluoroolefin. The manufacturing method according to claim 1, wherein the pressure is adjusted by discharging the gas phase in the reactor to the outside of the reactor. The production method according to claim 1 or 2, wherein the hydrofluorocarbon or hydrochlorofluorocarbon is monochlorotetrafluoropropane, and the fluoroolefin is tetrafluoropropene. The monochlorotetrafluoropropane is 2-chloro-1,1,1,2-tetrafluoropropane and / or 3-chloro-1,1,1,2-tetrafluoropropane, and the tetrafluoropropene is 2,3. , 3, 3-Tetrafluoropropene, the production method according to claim 3. The production method according to claim 4, wherein the pressure in the reactor is adjusted to 2.0 MPaG or less. The production method according to claim 1 or 2, wherein the hydrofluorocarbon or hydrochlorofluorocarbon is dichlorotetrafluoropropane, and the fluoroolefin is monochlorotetrafluoropropene. The dichlorotetrafluoropropane is 2,3-dichloro-1,1,1,2-tetrafluoropropane and / or 3,3-dichloro-1,1,1,2-tetrafluoropropane, and the monochlorotetrafluoropropane. The production method according to claim 6, wherein the propene is 1-chloro-2,3,3,3-tetrafluoropropene. The production method according to claim 7, wherein the pressure in the reactor is adjusted to 0.5 MPaG or less.

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