WO2018079727A1 - Production method for 2,3,3,3-tetrafluoropropene - Google Patents

Abstract

Provided is a method for efficiently producing 2,3,3,3,-tetrafluoropropene from easily obtainable raw materials by means of a simple reaction operation using a safe and economical but highly active catalyst. A production method for 2,3,3,3-tetrafluoropropene in which 2,3,3,3-tetrafluoropropene is obtained by bringing a fluorine-containing propane represented by general formula (1) (CF₂Cl-CFX-CH₂Y, in which one of X and Y is H and the other is F or Cl) into contact with a catalyst that includes a metal fluoride that comprises at least one fluoride of a metal selected from among the alkali metals, the alkali earth metals, aluminum, and zirconium (provided that, when one of X and Y in general formula (1) is H and the other is Cl, the fluorine-containing propane is brought into contact with the catalyst that includes the metal fluoride in the presence of hydrogen fluoride).

Description

Method for producing 2,3,3,3-tetrafluoropropene

The present invention relates to a method for producing 2,3,3,3-tetrafluoropropene.

2,3,3,3-tetrafluoropropene (CF ₃ CF═CH ₂ , HFO-1234yf; hereinafter also referred to as 1234yf) is a compound that has low toxicity and low impact on global warming, and has a greenhouse effect In recent years, great expectations have been placed on a new refrigerant that replaces the gas 1,1,1,2-tetrafluoroethane (HFC-134a).

As a method for producing 1234yf, methods using various reaction mechanisms using various raw material components are known. Among them, Patent Document 1 and Patent Document 2 include 1-chloro-1,1,2,2-tetrafluoropropane (CF ₂₎ as a method that can be efficiently produced from a readily available raw material by a one-step reaction operation. 1234yf by contacting Cl—CF ₂ —CH ₃ , HCFC-244cc (hereinafter also referred to as “244cc”) with a catalyst selected from chromium oxide, fluorinated chromium oxide and iron fluoride in the gas phase. Is described.

In Patent Document 3, 244 cc is brought into contact with a Lewis acid catalyst to obtain 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb), which is a structural isomer, and 1234yf is produced. A method is described. In Patent Document 3, various aluminum compounds and zirconium compounds are described as Lewis acid catalysts, and examples using aluminum oxide and zirconium oxide are described in Examples.

Japanese Patent No. 5348240 Japanese Patent No. 5413451 International Publication No. 2009/148191

However, in the production method of 1234yf in Patent Document 1 and Patent Document 2, when a chromium compound is used as a catalyst, safety and economic efficiency are reduced due to the strong toxicity of hexavalent chromium and the accompanying severe process control. However, when iron fluoride was used as a catalyst, the conversion rate of 244 cc was not sufficiently high. Furthermore, in the manufacturing method of Patent Document 3, when aluminum oxide or zirconium oxide was used as the catalyst, the selectivity of 1234yf was not sufficiently high.

The present invention has been made from the above viewpoint, and provides a method for efficiently producing 1234yf from a readily available raw material by a simple reaction operation using a highly active catalyst while being safe and economical. This is the issue.

The present invention provides a method for producing 2,3,3,3-tetrafluoropropene (1234yf) having the following constitution. In the present specification, for a halogenated hydrocarbon, the abbreviation of the compound is described in parentheses after the compound name, and the abbreviation is used instead of the compound name as necessary. In addition, as abbreviations, only numbers after the hyphen (-) and lower-case alphabetic characters (for example, "1234yf" in "HFO-1234yf") may be used. In this specification, “to” representing a numerical range includes upper and lower limits.

[1] General formula (1): CF ₂ Cl—CFX—CH ₂ Y (in general formula (1), one of X and Y is H and the other is F or Cl). Fluorine propane is contacted with a catalyst containing a metal fluoride consisting of at least one metal fluoride selected from alkali metals, alkaline earth metals, aluminum and zirconium (provided that the fluorinated propane is represented by the general formula ( In the case of fluorine-containing propane in which one of X and Y in 1) is H and the other is Cl, it is brought into contact with the catalyst containing the metal fluoride in the presence of hydrogen fluoride) 2, 3, 3, A method for producing 1234yf to obtain 3-tetrafluoropropene (1234yf) (hereinafter referred to as a method for producing 1234yf of the first embodiment).
[2] The method for producing 1234yf according to [1], wherein the fluorine-containing propane is contacted with the catalyst containing the metal fluoride in a gas phase.
[3] The method for producing 1234yf according to [1] or [2], wherein the fluorine-containing propane is 1-chloro-1,1,2,2-tetrafluoropropane (244 cc).
[4] The fluorine-containing propane is brought into contact with the catalyst containing the metal fluoride to obtain a reaction product, and the obtained reaction product is obtained from a metal oxide, a partial halide of the metal oxide, and a metal halide. The method for producing 1234yf according to [1], wherein the catalyst is brought into contact with a catalyst containing at least one selected metal compound.
[5] The method for producing 1234yf according to [4], wherein the fluorine-containing propane is contacted with a catalyst containing the metal fluoride in a gas phase, and the reaction product is contacted with a catalyst containing the metal compound in a gas phase.
[6] The method for producing 1234yf according to [4] or [5], wherein the fluorine-containing propane is 244 cc.
[7] Tetrafluoroethylene is reacted with at least one selected from CCl ₄ , CHCl ₃ and CH ₂ Cl ₂ to give a general formula (2): CF ₂ Cl—CF ₂ —CClAB (general formula (2) Wherein A and B are independently of each other H or Cl.)
A second step of obtaining 244 cc by hydrogenating the compound represented by the general formula (2) obtained in the first step,
The method for producing 1234yf according to any one of [1] to [6], wherein 244 cc obtained in the second step is brought into contact with the catalyst containing the metal fluoride.
[8] By reacting tetrafluoroethylene with at least one selected from CCl ₄ , CHCl ₃ and CH ₂ Cl ₂ , a general formula (2): CF ₂ Cl—CF ₂ —CClAB (general formula (2) Wherein A and B are independently of each other H or Cl.)
A second step of obtaining 244 cc by hydrogenating the compound represented by the general formula (2) obtained in the first step,
1234yf according to any one of [4] to [6], wherein a reaction product is obtained by contacting with the catalyst containing the metal fluoride, and the obtained reaction product is contacted with the catalyst containing the metal compound. Production method.
[9] A third step of reacting tetrafluoroethylene with chloromethane to obtain 244 cc,
The method for producing 1234yf according to any one of [1] to [6], wherein 244 cc obtained in the third step is brought into contact with the catalyst containing the metal fluoride.
[10] A third step of reacting tetrafluoroethylene with chloromethane to obtain 244 cc,
244 cc obtained in the third step is brought into contact with the catalyst containing the metal fluoride to obtain a reaction product, and the obtained reaction product is brought into contact with the catalyst containing the metal compound [4] to [ 6] The manufacturing method of 1234yf in any one of.
[11] The method for producing 1234yf according to any one of [1] to [10], wherein the metal fluoride is at least one of aluminum fluoride and calcium fluoride.
[12] The method for producing 1234yf according to any one of [1] to [11], wherein the metal fluoride is aluminum fluoride.
[13] 3-Chloro-2,3,3-trifluoropropene (CClF ₂ CF═CH ₂ , HCFO-1233yf; hereinafter also referred to as 1233yf) in the presence of hydrogen fluoride in the presence of a metal oxide or metal oxide A method for producing 1234yf obtained by contacting with a catalyst containing at least one metal compound selected from the group consisting of a partial halide and a metal halide (hereinafter referred to as a method for producing 1234yf in the second embodiment).
[14] The method for producing 1234yf according to [13], wherein the metal compound is composed of at least one selected from calcium fluoride, calcium oxide partial fluoride, cobalt chloride, and cobalt chloride partial fluoride.

According to the present invention, 1234yf can be efficiently produced from a readily available raw material by a simple reaction operation using a highly active catalyst while being safe and economical.

It is a schematic diagram showing an example of the reaction apparatus used for one Embodiment of the manufacturing method of this invention. It is a schematic diagram showing an example of the reaction apparatus used for another embodiment of the manufacturing method of this invention.

Hereinafter, embodiments of the present invention will be described in detail.
[Method for Producing 1234yf of First Embodiment]
The method for producing 1234yf of the first aspect of the present invention (hereinafter also referred to as production method (I)) is a compound represented by the general formula (1): CF ₂ Cl—CFX—CH ₂ Y (in the general formula (1), X And Y represents a fluorine-containing propane (hereinafter also referred to as fluorine-containing propane (1)), one of which is H and the other is F or Cl.), An alkali metal, an alkaline earth metal, aluminum and 1234yf is obtained by contacting with a catalyst containing a metal fluoride composed of at least one metal fluoride selected from zirconium (hereinafter also referred to as “catalyst (C1)”). However, when the fluorine-containing propane is a fluorine-containing propane in which one of X and Y in the general formula (1) is H and the other is Cl, the catalyst (C1) and Make contact.

In the reaction that occurs when the fluorinated propane (1) is brought into contact with the catalyst (C1), the fluorinated propane (1) is removed by XY (HCl or HF) mainly by a two-stage reaction represented by the following formula (a). 1233yf is produced (indicated by “reaction (a-1)” in formula (a)), and then the chlorine atom at the 3-position of 1233yf is substituted with a fluorine atom to produce 1234yf (in formula (a), “Reaction (a-2)”).

Here, when the combination of X and Y in the fluorine-containing propane (1) is H and F, HF generated during the production of 1233yf is used for the halogen substitution reaction of 1233yf. However, when the combination of X and Y in the fluorinated propane (1) is H and Cl, only HCl is produced when 1233yf is produced. To produce 1234yf by replacing 1233yf with halogen, HF is added to the reaction system. It is essential to introduce.

In the production method (I), in the reaction carried out by contacting the fluorine-containing propane (1) with the catalyst, the catalyst is made of at least one metal fluoride selected from alkali metals, alkaline earth metals, aluminum and zirconium. By selecting a catalyst containing a metal fluoride, it is possible to selectively and efficiently carry out the reaction represented by the formula (a).

According to the production method (I), the metal contained in the catalyst is safe and economical as described above. Further, 1234yf can be produced by carrying out the reaction (a-1) and the reaction (a-2) by a simple operation of bringing the fluorine-containing propane (1), which is easily available, into contact with the catalyst (C1). Furthermore, according to the production method (I), as shown in the examples described later, the conversion rate of the fluorine-containing propane (1) and the selectivity of 1234yf are both higher than industrially available values. . Moreover, the sum of the selectivity of 1233yf and 1234yf is high, which supports that the reaction of the formula (a) is selectively carried out in the reaction using the fluorine-containing propane (1) catalyst.

Here, the catalyst (C1) is a catalyst that generates the reaction (a-1) that produces 1233yf from the fluorine-containing propane (1) by XY, that is, deHCl or HF, particularly selectively and efficiently. is there. If the reaction (a-1) is carried out selectively and efficiently, the fluorine-containing propane (1) to its isomer, for example, 244 cc to 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb ), Is suppressed, and 1233yf is selectively produced. The produced 1233yf is halogen-substituted by reaction (a-2) to become 1234yf. In this way, the sum of the selection rates of 1233yf and 1234yf increases.

In order to efficiently perform the two-stage reaction represented by the formula (a), first, it is essential to promote the reaction (a-1). For this reason, in the production method (I), the catalyst (C1) is used. use. In the production method (I), in addition to the use of the catalyst (C1), the metal oxide, the partial halide of the metal oxide, and the metal are preferably used in order to efficiently perform the reaction (a-2). A catalyst containing at least one metal compound selected from halides (hereinafter also referred to as “catalyst (C2)”) is used in combination.

Specifically, in the production method (I), the fluorinated propane (1) is brought into contact with the catalyst (C1) (hereinafter referred to as a first contact step) to obtain a reaction product, and the obtained reaction product. Is preferably brought into contact with the catalyst (C2) (hereinafter referred to as second contact step). That is, it is preferable that the manufacturing method (I) has at least a first contact step and has a second contact step after the first contact step. In the case of having the first contact step and the second contact step, in the production method (I) for obtaining 1234yf from the fluorine-containing propane (1), each of the reaction (a-1) and the reaction (a-2) A preferred catalyst can be used in combination.

In addition, the reaction product (henceforth reaction product (11)) obtained at the 1st contact process which makes fluorine-containing propane (1) contact with a catalyst (C1) is unreacted fluorine-containing propane (1). , 1233yf, XY, 1234yf, HCl, the product according to formula (a). In the second contact step, the reaction product (11) obtained in the first contact step is brought into contact with the catalyst (C2).

In the second contact step in which the reaction product (11) contacts the catalyst (C2), only the reaction (a-2) in which 1234yf contained in the reaction product (11) does not react and 1233yf becomes 1234yf is the catalyst. It is preferable to be promoted by (C2). Then, in the final reaction product in the production method (I) obtained after the reaction product (11) comes into contact with the catalyst (C2), the content of 1234yf is high, and the fluorine-containing propane (1) The selectivity of 1234yf is also high.

Here, the method of performing the reaction (a-2) using the catalyst (C2) to obtain 1234yf from 1233yf corresponds to the method for producing 1234yf of the second aspect of the present invention described later. Therefore, even if the selectivity of 1234yf is slightly low in the production method (I), if the sum of the selectivity of 1233yf and 1234yf is high, 1233yf obtained at a high selectivity is further reacted using the catalyst (C2). 1234yf can be manufactured efficiently.

As described above, in the production method (I), when the combination of X and Y in the fluorinated propane (1) is H and F, 1234yf can be obtained by using the catalyst (C1) without particularly introducing HF into the reaction system. Can be manufactured efficiently. In this case, 1234yf may be produced while introducing HF into the reaction system.

Specifically, the fluorine-containing propane (1) is 244 cc in which X is F and Y is H in the general formula (1), and 1-chloro-1,1,2 in which X is H and Y is F , 3-tetrafluoropropane (HCFC-244ec; hereinafter also referred to as 244ec), 1,2-dichloro-1,1,2-trifluoropropane (HCFC-243bc; hereinafter, X is Cl and Y is H) ), 4 compounds of 1,3-dichloro-1,1,2-trifluoropropane (HCFC-243ec; hereinafter also referred to as 243ec) in which X is H and Y is Cl. is there. The fluorine-containing propane (1) used in the production method (I) may be one kind or two or more kinds.

Of the above four compounds, in the production method (I), 244 cc is preferable in terms of the productivity of 1234yf and the availability of the compound itself. Hereinafter, the production method (I) of the present invention will be described by taking as an example the production of 1234yf using 244 cc as the fluorine-containing propane (1).

(244cc)
244cc used as a raw material of manufacturing method (I) can be manufactured by a well-known method. The method for obtaining 244cc is not particularly limited, and for example, it can be produced by the following method (A) or method (B).

Method (A): Tetrafluoroethylene (TFE) is reacted with at least one selected from CCl ₄ , CHCl ₃ and CH ₂ Cl ₂ to give a general formula (2): CF ₂ Cl—CF ₂ —CClAB ( In the general formula (2), A and B are each independently H or Cl. The first step of obtaining a compound represented by the following (hereinafter also referred to as compound (2)), A method comprising a second step of obtaining 244 cc by hydrogenating the compound represented by the general formula (2) obtained in the step.
Method (B): A method having a third step of reacting TFE with CH ₃ Cl to obtain 244 cc.

In the method (A), in the first step, TFE is reacted with at least one selected from CCl ₄ , CHCl ₃ and CH ₂ Cl _{2 in} the presence of a Lewis acid catalyst such as aluminum chloride, for example. As the compound (2), 1,3,3,3-tetrachloro-1,1,2,2-tetrafluoropropane (CFC-214cb; hereinafter referred to as 214cb) in which A and B are both Cl in the general formula (2) 1,3,3-trichloro-1,1,2,2-tetrafluoropropane (HCFC-224ca; hereinafter also referred to as 224ca), A, and B, wherein A and B are a combination of Cl and H. At least one of 1,3-dichloro-1,1,2,2-tetrafluoropropane (HCFC-234cc; hereinafter also referred to as 234cc) in which B is H is obtained. .

Next, in the second step, at least one selected from 214cb, 224ca and 234cc is reacted with hydrogen in the presence of, for example, a palladium catalyst to obtain a reaction product containing 244cc. In addition, in the reaction product containing 244 cc obtained by the method (A), in addition to 244 cc, TFE, 214 cb, 224 ca, 234 cc, CCl ₄ , CHCl ₃ , CH ₂ Cl ₂ , which are production raw materials, By-products and other by-products are included.

In the method (B), TFE and CH ₃ Cl are reacted in the presence of a Lewis acid catalyst in the same manner as described above by appropriately adjusting the reaction conditions such as temperature, pressure, raw material supply ratio, etc. to obtain a reaction product containing 244 cc. . In addition to 244 cc, the reaction product containing 244 cc obtained by the method (B) includes TFE and CH ₃ Cl as production raw materials, and by-products produced as by-products in the production process.

As 244cc used for manufacturing method (I), what raised the purity of 244cc by well-known purification processes, such as distillation, extractive distillation, azeotropic distillation, membrane separation, two-layer separation, adsorption, etc. may be used, for example, You may use the composition containing components (impurities) other than 244cc and 244cc like the reaction product obtained above. However, in the case of using the latter composition, it is preferable to remove in advance if the impurity is an impurity active in the reaction in the production method (I).

(Catalyst (C1) and Catalyst (C2))
In the production method (I), 1234yf is obtained by the first contact step in which 244 cc as the fluorinated propane (1) obtained by the above method or the like is brought into contact with the catalyst (C1). In the production method (I), preferably, after the first contact step in which 244 cc as the fluorine-containing propane (1) is brought into contact with the catalyst (C1), the reaction product (11 obtained in the first contact step) ) To obtain 1234yf through a second contact step in which the catalyst (C2) is contacted.

The catalyst (C1) contains a metal fluoride consisting of at least one metal fluoride selected from alkali metals, alkaline earth metals, aluminum and zirconium, and produces a reaction 1234yf from the fluorine-containing propane (1), specifically Specifically, the reactivity of the reaction represented by the above formula (a), particularly the reaction (a-1) is improved and the reaction is promoted. By using the catalyst (C1), the production efficiency of 1234yf can be improved.

Among the metals constituting the metal fluoride, specifically, alkali metals include Li, Na, K, and Cs, and specific alkaline earth metals include Mg, Ca, Sr, and Ba. . That is, examples of the metal in the metal fluoride contained in the catalyst (C1) include Li, Na, K, Cs, Mg, Ca, Sr, Ba, Al, and Zr. The metal constituting the metal fluoride may be one kind or two or more kinds. When composed of two or more metals, it is a composite metal fluoride of two or more metals. Further, the metal fluoride contained in the catalyst (C1) may be composed of one kind of these metal fluorides, or may be composed of two or more kinds.

As the metal fluoride contained in the catalyst (C1), the reaction for generating 1234yf from the fluorine-containing propane (1), specifically, the reactivity of the reaction represented by the above formula (a) is improved, and the reaction is carried out. From the viewpoint of promoting and increasing the total value of the selectivity of 1233yf and the selectivity of 1234yf, one or more selected from aluminum fluoride, calcium fluoride and zirconium fluoride are preferable, and from aluminum fluoride and calcium fluoride One or more selected are more preferable. Furthermore, aluminum fluoride is particularly preferable from the viewpoint of increasing the conversion rate of fluorine-containing propane (1).

The catalyst (C1) is preferably used only with the above metal fluoride not containing other catalysts. Furthermore, the catalyst (C1) is preferably composed of a single compound of each of the metal fluorides, more preferably composed of only one selected from aluminum fluoride, calcium fluoride and zirconium fluoride. Further, it is more preferably composed of aluminum fluoride alone or calcium fluoride alone, and particularly preferably composed of aluminum fluoride alone. Even when the catalyst (C1) is composed of a single compound of each metal fluoride, the catalyst (C1) may contain impurities or the like as long as the effects of the present invention are not impaired. .

The catalyst (C1) is selected from, for example, a metal oxide, a partial halide of metal oxide, and a metal halide contained in the catalyst (C2) in addition to the metal fluoride, as long as the effects of the present invention are not impaired. It may contain at least one kind of metal compound or other catalyst. From the viewpoint of reducing the number of reaction steps, the catalyst (C1) and the catalyst (C2) are preferably used as a mixture and reacted in one step. However, it is preferable that the catalyst (C1) is used alone, particularly at least one of aluminum fluoride and calcium fluoride, and more preferably aluminum fluoride alone.

The catalyst (C2) contains at least one metal compound selected from metal oxides, metal oxide partial halides and metal halides, and is used in the second contact step in the production method (I). The catalyst (C2) improves the reactivity of the reaction (a-2) among the reactions represented by the above formula (a) and promotes the reaction. In the production method (I), in addition to the first contact step using the catalyst (C1), the second contact step using the catalyst (C2) is provided after the first contact step, so that 1234yf Manufacturing efficiency can be further improved.

Examples of the metal oxide in the catalyst (C2) include alkali metal oxides, alkaline earth metal oxides, aluminum oxide, zirconium oxide, titanium oxide, vanadium oxide, manganese oxide, zinc oxide, iron oxide, cobalt oxide, nickel oxide. , Copper oxide, palladium oxide, magnesium oxide, calcium oxide and the like, and aluminum oxide, cobalt oxide, and calcium oxide are preferable.

As the metal oxide of the metal oxide partial halide in the catalyst (C2), alkali metal oxide, alkaline earth metal oxide, aluminum oxide, zirconium oxide, titanium oxide, vanadium oxide, manganese oxide, zinc oxide, Examples thereof include iron oxide, cobalt oxide, nickel oxide, copper oxide, palladium oxide, and magnesium oxide. Examples of the halogen of the metal oxide partial halide include fluorine and chlorine. As the metal oxide partial halide, the metal oxide is preferably a partially fluorinated metal oxide partial fluoride, a calcium oxide partial fluoride, an aluminum oxide partial fluoride, and Cobalt oxide partial fluoride is particularly preferred, and calcium oxide partial fluoride is most preferred. In this case, the partial fluoride of the metal oxide may contain a halogen other than fluorine.

The partial halogenation of the metal oxide can be performed using an activation treatment agent as described below, for example. The metal halide partial halide is a compound in which at least a part of oxygen atoms are replaced with halogen atoms. The ratio of metal atoms, oxygen atoms, and halogen atoms is adjusted as appropriate.

The metal of the metal halide in the catalyst (C2) is at least one selected from alkali metals, alkaline earth metals, aluminum and titanium, zirconium, vanadium, manganese, zinc, iron, cobalt, nickel, copper, and palladium. Metal is preferred. As halogen, fluorine and chlorine are preferable, and both fluorine and chlorine may be contained. The metal halide in the catalyst (C2) is at least one metal fluoride selected from alkali metals, alkaline earth metals, aluminum and zirconium, or at least one selected from iron, cobalt, nickel, copper and palladium. More preferred is a metal chloride or a partial fluoride of at least one metal chloride selected from iron, cobalt, nickel, copper, palladium, and a partial fluorine of calcium fluoride, aluminum fluoride, cobalt chloride and cobalt chloride. Are particularly preferred, with calcium fluoride and cobalt chloride being most preferred.

The metal compound contained in the catalyst (C2) may be composed of only one kind or two or more kinds. The catalyst (C2) may contain a catalyst or impurities other than the above metal compound as long as the effects of the present invention are not impaired.

The catalyst (C1) and the catalyst (C2) are molded or treated as follows and used in the production method (I), for example. The molding or treatment common to the catalyst (C1) and the catalyst (C2) will be described using the term catalyst (C) as a general term for the catalyst (C1) and the catalyst (C2).

The catalyst (C) may be used as catalyst pellets obtained by crushing the catalyst (C) into a powder and then molding it with a tableting machine or the like in order to improve the reactivity.

The catalyst pellet may have a diameter of about 3.0 mm and a height of about 4.0 mm, for example. Further, in the catalyst pellets, a binder such as carbon, cellulose, alumina, silica, etc., if necessary, is 100 parts by mass or less, preferably 50 parts by mass or less, more preferably 100 parts by mass of the catalyst (C). You may mix in 10 mass parts or less.

The catalyst (C) may be used by being supported on a carrier. Examples of the carrier include carbon materials such as activated carbon, carbon black, and carbon fiber, and oxide materials such as alumina, silica, titania, zirconia, alkali metal oxides, and alkaline earth metal oxides. Silica, zirconia, alkali metal oxides and alkaline earth metal oxides are preferred. Among these, activated carbon, alumina, and zirconia are particularly preferable because they have a large specific surface area and can easily carry the catalyst.

The catalyst (C) is preferably dried in advance in an inert atmosphere, for example, in a nitrogen stream in order to improve the reactivity. When the catalyst (C) is dried, the catalyst (C) is contained in a reactor in the case where the reaction is performed in a gas phase, for example, from the viewpoint of simplification of operation and improvement of working efficiency. You may dry similarly to the above. Further, when the catalyst (C) is supported as a catalyst pellet or supported on a support in a gas phase reaction and accommodated in the reactor, the catalyst (C) is preliminarily stored in the catalyst pellet or support before being accommodated in the reactor or in the reactor. It may be dried in a supported state.

The specific surface area of the catalyst or catalyst pellet depends on the type of each catalyst. Generally, the smaller the value, the lower the conversion rate, and the larger the value, the lower the selectivity and the faster the deterioration. The reaction shown in a) is hardly affected. For example, when the binder is not used, the specific surface area of the metal oxide catalyst and the metal oxide partial halide catalyst is preferably 10 to 400 m ² / g, and the specific surface area of the metal halide catalyst is preferably 3 to 300 m ² / g. . When using the above binder, it depends on the specific surface area of the binder, so it cannot be said unconditionally. For example, when a high specific surface area carbon binder is used, the specific surface area of the mixture of the catalyst and the carbon binder is 20 to 1200 m ² / About g is preferable. In the present specification, the specific surface area is a value measured by the BET method.

Further, the catalyst (C) is preferably activated in advance from the viewpoint of improving the reactivity. Examples of the activation treatment method include a method of bringing the catalyst (C) into contact with the activation treatment agent under heating or non-heating. As the activation treatment agent, for example, hydrogen fluoride, hydrogen chloride, halogen-containing hydrocarbon, perhalogenated carbon, or the like can be used. As an activation processing agent, 1 type may be used independently and 2 or more types may be used together.

Among them, it is preferable to use hydrogen fluoride, perhalogenated carbon, or fluorine-containing hydrocarbon as the activation treatment agent. Examples of the perhalogenated carbon used as the activation treatment agent include carbon tetrachloride, trichlorofluoromethane (CFC-11), dichlorodifluoromethane (CFC-12), chlorotrifluoromethane (CFC-13), tetrafluoroethylene ( TFE), chlorotrifluoroethylene (CTFE) and the like are suitable. Examples of the fluorine-containing hydrocarbon include dichlorofluoromethane (HCFC-21), chlorodifluoromethane (HCFC-22), and trifluoromethane (HFC-23). Is preferred. Among these, HCFC-22, HFC-23, and hydrogen fluoride are more preferable, and HFC-23 is particularly preferable. Moreover, in the manufacturing method of this invention, you may use fluorine-containing propane (1), such as 244cc which is a raw material, as an activation processing agent.

In addition, among the above-described catalysts, a catalyst made of a metal oxide is activated using the hydrogen fluoride, the fluorine-containing hydrocarbon, or the fluorine-containing perhalogenated carbon, so that a partial halide of the metal oxide ( (Partial fluoride) can be produced.

The catalyst (C) may be activated before being accommodated in the reactor. However, since the operation is simple and the work efficiency is high, the activation treatment may be performed in the state accommodated in the reactor. preferable. Therefore, it is preferable to perform the activation treatment by introducing the activation treatment agent into the reactor containing the catalyst (C). The activation treatment agent may be introduced into the reactor at room temperature, but from the viewpoint of improving reactivity, it is preferable to adjust the temperature by heating or the like when introduced into the reactor.

Also, in order to increase the efficiency of the activation treatment, it is preferable to carry out the activation treatment with the inside of the reactor heated. In that case, the temperature in the reactor is preferably heated to 50 to 500 ° C.

Moreover, in order to increase the efficiency of the activation treatment, when the catalyst (C) is used after being dried, it is preferable to carry out the activation treatment after the catalyst (C) is dried. When the activation treatment is performed after the catalyst (C) is dried, the catalyst (C) is preferably dried in a state of being accommodated in the reactor, and then the activation treatment is preferably performed.

In addition to the activation treatment before the reaction, a reactivation treatment can be performed on the catalyst. That is, when the activity of the catalyst falls and the conversion rate to the fluorinated propene (2) is lowered, the catalyst can be reactivated. Thereby, the activity of the catalyst can be regenerated and the catalyst can be reused.

Examples of the reactivation treatment method include a method in which the catalyst is brought into contact with the activation treatment agent under heating or non-heating as in the activation treatment before use. As a treatment agent for reactivation treatment (reactivation treatment agent), oxygen, chlorine, hydrogen fluoride, hydrogen chloride, halogen-containing hydrocarbon, perhalogenated carbon, or the like can be used. Examples of the halogen-containing hydrocarbon and perhalogenated carbon include the same compounds as described above. Further, in the reactivation treatment, an inert gas such as nitrogen, carbon dioxide, or a rare gas (such as helium) is used to dilute the reactivation treatment agent from the viewpoint of suppressing side reactions and improving the durability of the catalyst. be able to.

Moreover, by bringing the reactivation treatment agent into contact with the catalyst layer together with the fluorine-containing propane (1), the catalyst can be reactivated in the reaction system, and the decrease in the activity of the catalyst can be suppressed. The reactivation treatment agent is supplied to the fluorine-containing propane (1) supplied to the reactor (however, when a composition containing the fluorine-containing propane (1) is used as a raw material, 0.001 to 1000 mol% is preferred. From the viewpoint of enhancing the reactivation effect of the catalyst, 0.01 mol% or more is more preferable, 0.05% or more is more preferable, and 0.1% or more is particularly preferable. From the viewpoint of improving the volumetric efficiency of the reactor and reducing impurities derived from the reactivation treatment agent, it is preferably 100 mol% or less, more preferably 10 mol% or less, and particularly preferably 1 mol% or less.

(Production of 1234yf by Production Method (I))
<First contact step>
In the production method (I), a method of bringing 244 cc, which is fluorine-containing propane (1), into contact with the catalyst (C1) includes a method in which 244 cc and the catalyst (C1) are brought into contact with each other in the reactor. It is preferable to use the catalyst (C1) after filling the reactor to form a catalyst layer. A method of bringing 244 cc into contact with the catalyst (C1) in the presence of hydrogen fluoride can be performed by supplying hydrogen fluoride into a reactor in which 244 cc and the catalyst (C1) are brought into contact with each other.

In the production method (I), when 244 cc and / or 244ec are used as the fluorinated propane (1), it is not essential to supply hydrogen fluoride to the reactor as described above. That is, 1234yf can be efficiently produced by using the catalyst (C1) without particularly introducing HF into the reaction system. However, in this case, 1234yf may be produced while introducing HF into the reaction system. Moreover, when using 243bc and / or 243ec as fluorine-containing propane (1), supply of hydrogen fluoride to the reactor is essential as described above.

The contact between 244cc and the catalyst (C1) may be performed in the liquid phase or in the gas phase. The reaction in the gas phase is preferable because the reaction time can be shortened and the production of by-products can be suppressed.

Manufacturing method (I) can be performed by either a batch method or a continuous method. The production method (I) is preferably a continuous method in terms of production efficiency.

When the production method (I) is carried out in the gas phase, it can be carried out by a method in which 244 cc of fluorinated propane (1) is allowed to flow through the reactor containing the catalyst (C1) for a predetermined time. In this case, it is preferable to supply dilution gas to the reactor together with 244 cc from the viewpoint of suppression of side reactions, ease of supply to the 244 cc reactor, and ease of adjustment of the flow rate. Further, there is an advantage that the durability of the catalyst is improved by using a dilution gas.

Examples of the dilution gas include nitrogen, carbon dioxide, rare gas (such as helium), and an organic compound gas that is inert in the reaction of the present embodiment. Inactive organic compounds include saturated hydrocarbons such as methane, ethane, propane, butane, pentane and hexane, fluorohydrocarbons such as difluoromethane (HFC-32), hexafluoroethane (FC-216), and octafluoro. And perfluorocarbons such as propane (FC-318). The amount of the dilution gas is not particularly limited, but specifically, it is 1 to 244 cc supplied to the reactor (however, when a composition containing 244 cc is used as a raw material) An amount of 10,000 mol%, preferably 10 to 1000 mol%, more preferably 30 to 500 mol% can be mentioned. Dilution gas may be used individually by 1 type, and may use 2 or more types together.

In the production method (I), 244 cc may be introduced into the reactor after preheating. In this case, the preheating temperature is preferably 20 to 500 ° C., more preferably 50 to 400 ° C., in order to vaporize 244 cc and improve the reactivity.

In the case of using a dilution gas, 244 cc and the dilution gas may be introduced into the reactor after being preheated to the above preferred temperature from the viewpoint of improving the reactivity. 244 cc and dilution gas may be mixed after preheating to the above temperature, and then supplied to the reactor, or after mixing 244 cc and dilution gas, preheated and supplied to the reactor.

In the production method (I), when the contact between 244 cc and the catalyst (C1) is performed in a gas phase, the reaction pressure may be reduced or increased. The reaction pressure when the production method (I) is carried out in the gas phase is preferably reduced pressure, normal pressure, or fine pressure of 1.0 MPa or less from the viewpoint of ease of industrial implementation.

The contact temperature (reaction temperature) between 244 cc and the catalyst (C1) depends on the type of metal fluoride used, but the temperature in the reactor is 200 to 500 ° C., preferably 250 to 450 ° C. If reaction temperature is more than a lower limit, the production | generation reaction of 1234yf can be advanced efficiently. On the other hand, if the reaction temperature is not more than the upper limit value, the production of by-products can be suppressed.

In the production method (I), the contact time (reaction time) between 244 cc and the catalyst (C1) in the reactor is preferably 0.1 to 1000 seconds, and more preferably 1 to 100 seconds. The contact time corresponds to the residence time in the 244 cc reactor and can be controlled by adjusting the supply amount (flow rate) to the 244 cc reactor.

In the production method (I), when hydrogen fluoride is supplied to the reactor, the supply amount of hydrogen fluoride is preferably 0.01 to 10 mol, particularly preferably 0.1 to 1 mol, relative to 1 mol of 244 cc. . The hydrogen fluoride may be preheated to the preferred temperature of 244 cc described above upon feeding to the reactor. Further, hydrogen fluoride is dried in advance and made anhydrous, and then supplied to the reactor.

When 244ec is used as the fluorine-containing propane (1), the supply amount of hydrogen fluoride is the same as that of 244cc. When 243bc and / or 243ec is used as the fluorine-containing propane (1), The supply amount of hydrogen is preferably 0.01 to 20 mol, particularly preferably 1 to 5 mol, relative to 1 mol of 243bc and / or 243ec.

<Second contact step>
In the production method (I), as a method of bringing the reaction product (11) obtained in the first contact step into contact with the catalyst (C2), the reaction product (11) and the catalyst (C2) are brought into the reactor. The method of making it contact is mentioned. The catalyst (C2) is preferably used by filling the reactor to form a catalyst layer. When the second contact step is performed in the presence of hydrogen fluoride, hydrogen fluoride can be supplied into the reactor in which the reaction product (11) and the catalyst (C2) are contacted.

As a method of performing the second contact step using a reactor, specifically, in the first contact step, 244 cc as fluorine-containing propane (1) is obtained by replacing the catalyst (C1) with the catalyst (C2). There is a method of supplying the reaction product (11) instead of supplying to the reactor. Preheating temperature of the reaction product (11), type when using a dilution gas, supply method, preheating temperature, reaction pressure in the reactor, contact time of the reaction product (11) and the catalyst (C2) (reaction time), The contact temperature (reaction temperature) can be the same as the first contact step.

When manufacturing method (I) has a 1st contact process and a 2nd contact process, the discharge port of the 1st reactor which has a catalyst layer which has a supply port, a discharge port, and was filled with the catalyst (C1), for example And a supply port of a second reactor having a supply port and a discharge port and having a catalyst layer filled with a catalyst (C2) may be used. In that case, by supplying 244 cc from the supply port of the first reactor, 244 cc flows through the catalyst layer of the catalyst (C1), and the obtained reaction product (11) is continuously supplied to the second reactor. The catalyst product of the catalyst (C2) is passed through, and a reaction product having a high content of 1234yf is obtained from the outlet of the second reactor.

Further, for example, a catalyst layer filled with the catalyst (C1) is provided on the upstream side in one reactor having a supply port and a discharge port, and a packed bed filled with the catalyst (C2) is provided on the downstream side. You may perform a 1st contact process and a 2nd contact process continuously within a reactor.

In addition, when manufacturing method (I) has a 1st contact process and a 2nd contact process, when supplying hydrogen fluoride to a reactor, hydrogen fluoride is supplied only in a 2nd contact process. Is preferred.

(Reactor)
The reactor used in the production method (I) is not particularly limited as long as it can withstand the temperature and pressure in the reactor described above. For example, a glass flask, an autoclave, or a cylindrical vertical reactor is used. be able to. As the material of the reactor, glass, iron, nickel, iron, an alloy containing nickel as a main component, or the like is used. Further, the reactor may be provided with an electric heater for heating the inside of the reactor.

(Reactor)
An example of a reaction apparatus used in the production method (I) is shown in FIG. The reaction apparatus 20 shown in FIG. 1 has the reactor 1 provided with heating means, such as an electric heater. The reactor 1 has a catalyst layer 2 filled with a catalyst (C1). In the reactor 20 shown in FIG. 1, the production method (I) having only the first contact step in which 244 cc, which is fluorine-containing propane (1), is brought into contact with the catalyst (C1) can be performed.

The reactor 1 is connected to a supply line 3 of 244 cc (indicated by “raw material” in FIG. 1) and a supply line 4 of dilution gas as follows. In addition, the installation of the heating means and the dilution gas supply line 4 in the reactor 1 is not essential, and is provided as necessary.

244 cc supply line 3 and dilution gas supply line 4 may be provided with preheaters (not shown) each equipped with an electric heater or the like. In this case, 244 cc and the dilution gas are each preheated to a predetermined temperature by the preheater and then supplied to the reactor 1.

The 244 cc supply line 3 and the dilution gas supply line 4 may be connected to the reactor 1 separately. However, as shown in FIG. 1, the 244 cc supply line 3 and the dilution gas supply line 4 are connected. In addition, a mixture of all components may be supplied to the reactor 1 by being connected to the reactor 1 via the 244 cc / dilution gas supply line 5. When the 244cc supply line 3 or the dilution gas supply line 4 includes a preheater, the 244cc supply line 3 or the dilution gas supply line 4 after passing through the preheater is connected, and the 244cc / dilution gas supply line 5 What is necessary is just to connect with the reactor 1.

When the production method (I) is performed by supplying hydrogen fluoride to the reactor 1, a hydrogen fluoride supply line may be provided separately from the 244cc supply line 3 and the dilution gas supply line 4. The dilution gas supply line 4 may be used to supply hydrogen fluoride. Specifically, there is a method such as switching the supply of the dilution gas to the supply of a mixture of hydrogen fluoride and the dilution gas after a predetermined time has passed after supplying the dilution gas using the supply line 4 at the beginning of the reaction. Can be mentioned.

The outlet line 6 is connected to the outlet of the reactor 1. Although not shown, a reaction product (hereinafter, also referred to as “crude gas”) obtained by the reaction is taken out from the outlet line 6, and each component contained in the reaction product is analyzed like gas chromatography (GC). You may make it the structure analyzed and quantified with an apparatus. A cooling means 7 such as a water cooler is installed in the outlet line 6, and further, a steam and acidic liquid recovery tank 8, an alkali cleaning device 9, and a dehydration tower 10 are sequentially installed. The crude gas after the reaction passes through each device from the outlet line 6 to the dehydration tower 10 in order to be washed with water, washed with alkali, dehydrated, and exit gas from which acid content, moisture and strong adsorptive components have been removed. As obtained from the outlet of the dehydration tower 10.

(Outlet gas component)
In the production method (I) using 244 cc as the fluorine-containing propane (1), 1234yf as the final target product, 1233yf as the intermediate product, and pentafluoropropane (CF ₃ —CF ₂ —CH ₃ as the by-product) HFC-245cb), 2-chloro-3,3,3-trifluoropropene (CF ₃ -CCl═CH ₂ , HCFO-1233xf), 1-chloro-2,3,3,3-tetrafluoropropene (Z ) (CF ₃ —CF═CHCl, HCFO-1224yd (Z)), 1-chloro-2,3,3,3-tetrafluoropropene (E) (CF ₃ —CF═CHCl, HCFO-1224yd (E)) 2-chloro-1,3,3,3-tetrafluoropropene (CF ₃ —CCl═CHF, HCFO-1224xe), 1, 2-dichloro-3,3,3-trifluoropropene (E) (CF ₃ —CCl═CHCl, HCFO-1223xd (E)), 1,2-dichloro-3,3,3-trifluoropropene (Z) (CF ₃ -CCl = CHCl, HCFO-1223xd (Z)), 1,1,2-trichloro-2-fluoroethene (CCl ₂ = CClF), 234 cc, 224 ca, C ₃ H ₂ FCl ₃ (HCFO-1231 isomerism ), C ₃ H ₂ F ₂ Cl ₂ (HCFO-1232 isomer) can be obtained as a component of the outlet gas. The above components other than 1234yf contained in the outlet gas can be removed to a desired extent by known means such as distillation, extractive distillation, azeotropic distillation, membrane separation, two-layer separation, and adsorption. In addition, 1233yf can be used as a raw material of the manufacturing method of 1234yf of the 2nd aspect of this invention demonstrated below.

(Reactivation of catalyst (C1))
Note that the activity of the catalyst (C1) may decrease due to continuous use, and the conversion rate of the fluorinated propane (1) may decrease. In that case, the following reactivation process can be performed on the catalyst (C1), whereby the activity of the catalyst (C1) can be regenerated and the catalyst (C1) can be reused. The method for the reactivation process is as described above.

FIG. 2 shows an example of a reaction apparatus used when the production method (I) has a first contact process and a second contact process. The reactor 30 shown in FIG. 2 is the same as the reactor 20 shown in FIG. 1 except that the configuration of the reactor 1 is different. That is, in the reactor 20, the catalyst layer 2 filled with the catalyst (C1) is formed in one reactor 1, whereas in the reactor 30, the reactor 1 is the catalyst in order from the upstream side. A first reactor 1A having a catalyst layer 2A filled with (C1) and a second reactor 1B having a catalyst layer 2B filled with a catalyst (C2) are connected to each other. A sampling line 11 is provided at a connecting portion connecting the first reactor 1A and the second reactor 1B.

In the reaction apparatus 30, the first contact step is performed in the catalyst layer 2A in the first reactor 1A, and then the second contact step is performed in the catalyst layer 2B in the second reactor 1B. When the reactor 30 is used, the supply of 244 cc, dilution gas and the like to the reactor 1, the processing after the outlet line 6, the analysis of the crude gas components, and the like can be performed in the same manner as in the reactor 20. Furthermore, the reactivation process of the catalyst (C2) can be performed simultaneously with the reactivation process of the catalyst (C1). In addition, when manufacturing method (I) is performed by supplying hydrogen fluoride to the reactor 1 using the reaction apparatus 30, the supply of hydrogen fluoride is performed using the first reactor 1A (catalyst layer 2A) and the second reactor. It is preferable to be performed between the reactors 1B (catalyst layer 2B).

The production method (I) has been described above using an example in which 244 cc is used as the fluorine-containing propane (1). However, the same applies to the case where 244ec, 243bc, and 243ec are used as the fluorine-containing propane (1). However, the supply of hydrogen fluoride is as described above. According to the production method (I), the easily obtained fluorine-containing propane (1), particularly 244 cc, is used as a raw material, and the reaction is carried out using the catalyst (C1). Can be manufactured. In addition, according to the production method (I), the sum of the selectivity of 1234yf and the selectivity of the intermediate 1233yf that can be easily converted to 1234yf can be increased. It can be said that it is a manufacturing method.

[Method for producing 1234yf of second aspect]
In the method for producing 1234yf of the second aspect of the present invention (hereinafter also referred to as production method (II)), 1233yf is treated with metal oxide, partial halide and metal halide of metal oxide in the presence of hydrogen fluoride. 1234yf is obtained by contacting with a catalyst containing at least one metal compound selected from the group consisting of:

The reaction according to the production method (II) is a reaction shown as the second-stage reaction of the formula (a), and requires supply of hydrogen fluoride. Although 1233yf which is a raw material of manufacturing method (II) can be obtained as described above by, for example, manufacturing method (I), it is not limited thereto. If 1233yf obtained by manufacturing method (I) is used, it can be set as a series of manufacturing methods of 1234yf, and is industrially advantageous.

The catalyst containing the metal compound used in the production method (II) can be the same as the catalyst (C2) used in the second contact step of the production method (I). A specific production method of production method (II) is that, when production method (I) is carried out only in the first contact step, fluorine-containing propane (1) is changed to 1233yf, and catalyst (C1) is changed to catalyst (C2 Except that the supply of hydrogen fluoride to a reaction system, for example, a reactor in a gas phase reaction, is essential.

Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited to these descriptions. Examples 1 to 8 and 11 to 13 are examples, and examples 9 and 10 are comparative examples.

[Preparation of 244cc]
According to the above method (A) from TFE and CHCl ₃ , 224 ca was produced in the first step, and 244 cc was produced from the obtained 224 ca in the second step.

(1) Production of 224ca According to the following reaction formula, 1,1,3-trichloro-2,2,3,3-tetrafluoropropane (224ca) was produced by the following procedure.
CHCl ₃ + TFE → 224ca

First, anhydrous aluminum chloride (25 g, 0.19 mol), CHCl ₃ (500 g, 4.19 mol) and 224ca (100 g, 0.45 mol) were put into a 500 mL stainless steel autoclave and degassed with stirring, and then TFE was added. Was supplied until the inside of the autoclave became 0.05 MPa, and the inside of the autoclave was heated to 80 ° C. Thereafter, TFE was further supplied while maintaining the pressure in the autoclave at 0.8 MPa. The total amount of TFE supplied to the autoclave was 0.17 kg (1.65 mol).

After further stirring for 1 hour, the reaction solution was cooled to room temperature and analyzed by gas chromatography. The conversion of CHCl ₃ was 33% and the selectivity of 224ca was 84%. To the crude liquid obtained by filtering the liquid after the reaction, 102 g of molecular sieve 4A was added and stirred overnight to dehydrate. 224ca (230 g, 1.05 mol) was manufactured by distilling and purifying the crude product obtained by separating the stirred crude liquid by filtration.

(2) Production of 244cc Using the 224ca obtained by the above method as a raw material, 244cc was obtained by the following method.

First, a gas phase reactor (made of SUS316, diameter 25 mm, length 30 cm) composed of a cylindrical reaction tube equipped with an electric furnace was charged with activated carbon pellets (15 g) supporting palladium at a ratio of 2.0% by weight, The temperature was raised to 130 ° C. while flowing nitrogen (N ₂ ) gas (500 NmL / min). While maintaining the reaction tube at atmospheric pressure (1 atm), the catalyst was dried until the moisture in the gas obtained from the outlet of the reaction tube became 20 ppm or less. After the drying of the catalyst was completed, the supply of nitrogen was stopped, the reaction tube was heated to 200 ° C. while supplying hydrogen (180 mL / min), and then 224ca (0.44 g / min) was supplied.

The crude gas obtained from the outlet of the reaction tube was washed with water, then acid and moisture were removed through an alkali washing tower and molecular sieve 5A, and then collected in a cold trap. When the collected crude product was analyzed by gas chromatography, the conversion rate of 224ca was 98%, and 234cc was obtained with a selectivity of 24% and 244cc with a selectivity of 70%. A total of 500 g (2.27 mol) of 224ca was reacted above to give 298 g of crude product.

The obtained crude product was subjected to normal pressure rectification in a 25-stage rectification column to obtain 244 cc (200 g, 1.33 mol).

(3) Production of 1234yf In Examples 1 to 10, a reactor similar to the reactor 20 shown in FIG. 1 was used, and 1234yf was produced using 244 cc obtained in (2) above. As the reactor 1, a tubular reactor made of SUS316 having an inner diameter of 16.1 mm and a length of 18 cm was used.

[Preparation of catalyst]
Catalysts (C11) to (C13) were prepared as catalysts (C1) used in the examples by the following method. Moreover, the catalyst (cf1) and the catalyst (cf2) were prepared as a catalyst used for a comparative example. Examples 1 to 8, which are examples, are examples in which only the first contact step was performed using the catalyst (C1) in the production method (I). Comparative examples 9 and 10 are examples in which a catalyst other than the catalyst (C1) was used instead of the catalyst (C1).

(Preparation of catalyst (C11))
A mixture obtained by adding 3 parts by mass of carbon to 97 parts by mass of aluminum fluoride (AlF ₃ , manufactured by Junsei Chemical Co., Ltd.) and mixing them uniformly was formed into catalyst pellets having a diameter of 3 mm and a height of 4 mm using a tableting machine. The pellets were charged into the reactor, and the temperature in the reactor was raised to 350 ° C. while flowing nitrogen (N ₂ ) gas (500 NmL / min). While maintaining the inside of the reactor at atmospheric pressure (1 atm) and 350 ° C., the catalyst pellets are dried until the moisture in the gas obtained from the outlet of the reactor becomes 20 ppm or less, and the catalyst (C11) is placed in the reactor. And a catalyst layer formed of catalyst pellets made of carbon. The catalyst (C11) is AlF ₃ subjected to the above treatment.

(Preparation of catalysts (C12) and (C13))
A catalyst formed of a pellet-like catalyst (C12) in the reactor in the same manner as the preparation of the catalyst (C11) except that the mixture of aluminum fluoride and carbon was changed to zirconium fluoride (ZrF ₄ , manufactured by Acros). A layer was obtained. A pellet-shaped catalyst (C13) was formed in the reactor in the same manner as the preparation of the catalyst (C11) except that the mixture of aluminum fluoride and carbon was changed to calcium fluoride (CaF ₂ , manufactured by Wako Pure Chemical Industries). A catalyst layer was obtained. The catalyst (C12) is ZrF ₄ subjected to the above treatment, and the catalyst (C13) is CaF ₂ subjected to the above treatment.

(Preparation of catalysts (cf1) and (cf2))
Zinc oxide (ZnO, manufactured by JGC Catalysts and Chemicals) was charged into the reactor, and the temperature in the reactor was increased to 250 ° C. while flowing nitrogen (N ₂ ) gas (500 NmL / min). While maintaining the reactor at atmospheric pressure (1 atm) and 250 ° C., the catalyst was dried until the moisture in the gas obtained from the outlet of the reactor was 20 ppm or less. After the drying of the catalyst was completed, the reactor was maintained at 250 ° C., and HCFC-22 was supplied to the reactor at a flow rate of 18.26 NmL / min and nitrogen at 36.52 NmL / min. This state was maintained for 8 hours, and the catalyst was activated to obtain a catalyst (cf1) constituting a catalyst layer in the reactor.

For the catalyst (cf2), a catalyst comprising a catalyst layer in the reactor in the same manner as the preparation of the catalyst (cf1) except that zinc oxide was changed to aluminum oxide (Al ₂ O ₃ , manufactured by JGC Catalysts & Chemicals) cf2) was obtained.

(Example 1)
After completion of drying of the catalyst (C11), HCFC-244cc was supplied to the reactor at a flow rate of 0.04 g / min and nitrogen at 5.97 NmL / min while maintaining the reactor at 350 ° C. The crude gas obtained from the reactor was passed through an aqueous solution of potassium hydroxide (KOH) having a concentration of 10% by mass to remove acidic components, and then passed through a dehydration tower packed with synthetic zeolite (Molecular Sieves 4A) for dehydration. As a result, an outlet gas from which acid content, moisture, and strongly adsorbing components were removed was obtained. The result of analyzing the crude gas 1 hour after the start of the supply to the 244 cc reactor using gas chromatography shows the reaction conditions (type of catalyst used, N ₂ supply flow rate, reactor internal temperature (reaction temperature), (Supply flow rate of 244 cc) is shown in Table 1.

As a result of the analysis of the crude gas, Table 1 shows the conversion rate of 244 cc, the selectivity of 1234yf (A), 1233yf (B), other components, and the sum of the selectivity of 1234yf and the selectivity of 1233yf (A + B). )showed that. The same applies to the following examples.

The outlet gas after dehydration was captured in a cylinder cooled with dry ice. The trapped outlet gas is used as a sample and supplied to the bottom of a distillation column having a theoretical plate number of about 45. Distillation is performed by batch distillation at an operating pressure of 0.8 MPa (gauge pressure), and 1234yf from the top of the distillation column. A distillate containing 99.8% was obtained.

(Examples 2 to 10)
In Example 1, 1234yf was produced in the same manner as in Example 1 except that the type of catalyst used, N ₂ supply flow rate, reactor internal temperature (reaction temperature), and 244 cc supply flow rate were changed to Table 1. Table 1 shows the analysis results of the crude gas measured in the same manner as in Example 1. In Examples 2 to 10, only analysis of crude gas was performed, and purification of 1234yf was not performed.

(Examples 11 to 13)
In Examples 11 to 13, 1234yf was produced using 244 cc obtained in the above (2) using the same reactor as the reactor 30 shown in FIG. The reactor 1 is an apparatus in which two tubular reactors made of SUS316 having an inner diameter of 16.1 mm and a length of 9 cm are connected in series (the first reactor 1A on the upstream side and the second reactor 1B on the downstream side). Was used. Examples 11 to 13 are production examples of 1234yf having the first contact step and the second contact step in the production method (I). Moreover, if the 2nd contact process in the 2nd reactor 1B is made independent, it can be said that it is a manufacture example of 1234yf by manufacturing method (II).

[Preparation of catalyst]
Catalysts (C21) to (C23) were prepared as catalysts (C2) used in the examples by the following method. In Examples 11 to 13, which are examples, the reaction product obtained in the first contact step is contacted with the catalyst (C2) after the first contact step using the catalyst (C1) in the production method (I). Through the second contacting step, 1234yf was obtained.

(Preparation of catalyst (C21))
A mixture obtained by adding 3 parts by mass of carbon to 97 parts by mass of aluminum fluoride (AlF ₃ , manufactured by Junsei Chemical Co., Ltd.) and mixing them uniformly was formed into catalyst pellets having a diameter of 3 mm and a height of 4 mm using a tableting machine. The pellet was charged into the first reactor 1A. Calcium fluoride (CaF ₂ , manufactured by Wako Pure Chemical Industries, Ltd.) was formed into catalyst pellets having a diameter of 3 mm and a height of 4 mm with a tableting machine, and the pellets were charged into the second reactor 1B. While flowing nitrogen (N ₂ ) gas (500 NmL / min), the temperature inside the reactor 1 was raised to 350 ° C. While maintaining the inside of the reactor 1 at atmospheric pressure (1 atm) and 350 ° C., the catalyst pellets are dried until the moisture in the gas obtained from the outlet of the reactor 1 becomes 20 ppm or less, and the first reactor 1A A catalyst layer formed of catalyst pellets (C11) inside and catalyst pellets (C21) inside the second reactor 1B was obtained. The catalyst (C11) is AlF ₃ subjected to the above treatment, and the catalyst (C21) is CaF ₂ subjected to the above treatment.

(Preparation of catalyst (C22))
Cobalt chloride hexahydrate (Wako Pure Chemical Industries, Ltd.) 24.4 g was dissolved in 125 mL of ion exchange water to prepare a cobalt chloride aqueous solution. This aqueous solution was impregnated with 77.5 g of alumina (Al ₂ O ₃ , N612N, manufactured by JGC Catalysts & Chemicals, Pellet) for 17 hours. After the pellet was filtered off, it was vacuum-dried at 100 ° C. for 12 hours to obtain 85.3 g of a blue pellet. Except that the calcium fluoride was changed to the above pellets, a pellet-shaped catalyst (C22) (a catalyst in which cobalt chloride was supported on alumina) was formed in the second reactor 1B in the same manner as the preparation of the catalyst (C21). A catalyst layer was obtained.

(Preparation of catalyst (C23))
A mixture obtained by adding 3 parts by mass of carbon to 97 parts by mass of aluminum fluoride (AlF ₃ , manufactured by Junsei Chemical Co., Ltd.) and mixing them uniformly was formed into catalyst pellets having a diameter of 3 mm and a height of 4 mm using a tableting machine. The pellet was charged into the first reactor 1A. Calcium oxide (CaO, manufactured by Yoshizawa Lime Industry) was charged into the second reactor 1B. While flowing nitrogen (N ₂ ) gas (500 NmL / min), the temperature inside the reactor 1 was raised to 350 ° C. While maintaining the inside of the reactor 1 at atmospheric pressure (1 atm) and 350 ° C., the catalyst pellets were dried until the moisture in the gas obtained from the outlet of the reactor 1 became 20 ppm or less. After the drying of the catalyst was completed, the temperature of the reactor 1 was raised to 450 ° C., and HFC-23 was supplied to the reactor 1 at a flow rate of 99.9 NmL / min and nitrogen was 72.3 NmL / min. This state was maintained for 14 hours, and the catalyst was activated. A catalyst layer formed of catalyst pellets composed of the catalyst (C11) in the first reactor 1A and the catalyst (C23) in the second reactor 1B was obtained. The catalyst (C11) is AlF ₃ subjected to the above treatment, and the catalyst (C23) is CaO partially fluorinated by the above treatment.

(Example 11)
As described above, after obtaining the catalyst layer formed of the catalyst pellets composed of the catalyst (C11) in the first reactor 1A and the catalyst (C21) in the second reactor 1B, the reactor 1 is heated to 350 ° C. The HCFC-244cc was supplied to the reactor 1 at a flow rate of 0.103 g / min and nitrogen at 15.44 NmL / min. The results of analysis of the first reactor 1A crude gas and the second reactor 1B crude gas one hour after the start of supply to the 244 cc reactor 1 using gas chromatography show the reaction conditions (of the catalyst used). Table 2 shows the type, N ₂ supply flow rate, reactor internal temperature (reaction temperature), and 244 cc supply flow rate). The first reactor 1A crude gas was extracted from the sampling line 11 provided at the connecting portion connecting the first reactor 1A and the second reactor 1B and analyzed.

(Examples 12 and 13)
In Example 11, 1234yf was produced in the same manner as in Example 11 except that the type of catalyst used, N ₂ supply flow rate, reactor internal temperature (reaction temperature), and 244 cc supply flow rate were changed to Table 2. Table 2 shows the analysis results of the crude gas measured in the same manner as in Example 11.

In Examples 11 to 13, in addition to the GC analysis of the crude gas, HF analysis was also performed by the ion electrode method. The analysis results are shown in Table 3. Comparing the crude gas compositions of the first reactor 1A and the second reactor 1B in Table 3, 1233yf and HF are consumed in the second reactor 1B, and 1234yf is generated. This result indicates that the catalysts (C21) to (C23) are suitable as the catalyst used in the second contacting step or the production method (II) in the production method (I).

DESCRIPTION OF SYMBOLS 1 ... Reactor, 2, 2A, 2B ... Catalyst layer, 3 ... Raw material supply line, 4 ... Dilution gas supply line, 5 ... Raw material / dilution gas supply line, 6 ... Outlet line, 7 ... Cooling means, 8 ... Steam and acidic liquid recovery tank, 9 ... alkali cleaning device, 10 ... dehydration tower, 11 ... sampling line, 20, 30 ... reactor.

Claims (14)

A fluorine-containing propane represented by the general formula (1): CF ₂ Cl—CFX—CH ₂ Y (in the general formula (1), one of X and Y is H and the other is F or Cl). In contact with a catalyst containing a metal fluoride comprising at least one metal fluoride selected from alkali metals, alkaline earth metals, aluminum and zirconium (wherein the fluorinated propane is represented by the general formula (1)) In the case of fluorine-containing propane in which one of X and Y is H and the other is Cl, it is brought into contact with the catalyst containing the metal fluoride in the presence of hydrogen fluoride) 2,3,3,3-tetra A process for producing 2,3,3,3-tetrafluoropropene to obtain fluoropropene. The method for producing 2,3,3,3-tetrafluoropropene according to claim 1, wherein the fluorine-containing propane is contacted with the catalyst containing the metal fluoride in a gas phase. The method for producing 2,3,3,3-tetrafluoropropene according to claim 1 or 2, wherein the fluorine-containing propane is 1-chloro-1,1,2,2-tetrafluoropropane. The fluorine-containing propane is contacted with the catalyst containing the metal fluoride to obtain a reaction product, and the obtained reaction product is at least selected from a metal oxide, a partial halide of a metal oxide, and a metal halide. The method for producing 2,3,3,3-tetrafluoropropene according to claim 1, wherein the catalyst is brought into contact with a catalyst containing one kind of metal compound. The said fluorine-containing propane is contacted with the catalyst containing the said metal fluoride in a gaseous phase, and the said reaction product is contacted with the catalyst containing the said metal compound in a gaseous phase. A process for the production of tetrafluoropropene. The method for producing 2,3,3,3-tetrafluoropropene according to claim 4 or 5, wherein the fluorine-containing propane is 1-chloro-1,1,2,2-tetrafluoropropane. Tetrafluoroethylene is reacted with at least one selected from CCl ₄ , CHCl ₃ and CH ₂ Cl ₂ to give a general formula (2): CF ₂ Cl—CF ₂ —CClAB (in general formula (2), A And B are independently of each other H or Cl.)
A second step of obtaining 1-chloro-1,1,2,2-tetrafluoropropane by hydrogenating the compound represented by the general formula (2) obtained in the first step. ,
The 1-chloro-1,1,2,2-tetrafluoropropane obtained in the second step is brought into contact with the catalyst containing the metal fluoride. A method for producing 3,3,3-tetrafluoropropene. Tetrafluoroethylene is reacted with at least one selected from CCl ₄ , CHCl ₃ and CH ₂ Cl ₂ to give a general formula (2): CF ₂ Cl—CF ₂ —CClAB (in general formula (2), A And B are independently of each other H or Cl.)
A second step of obtaining 1-chloro-1,1,2,2-tetrafluoropropane by hydrogenating the compound represented by the general formula (2) obtained in the first step. ,
The 1-chloro-1,1,2,2-tetrafluoropropane obtained in the second step is contacted with the catalyst containing the metal fluoride to obtain a reaction product, and the obtained reaction product The method for producing 2,3,3,3-tetrafluoropropene according to any one of claims 4 to 6, wherein is contacted with a catalyst containing the metal compound. A third step of reacting tetrafluoroethylene with chloromethane to obtain 1-chloro-1,1,2,2-tetrafluoropropane;
The 2,3 according to any one of claims 1 to 6, wherein 1-chloro-1,1,2,2-tetrafluoropropane obtained in the third step is brought into contact with the catalyst containing the metal fluoride. , 3,3-Tetrafluoropropene production method. A third step of reacting tetrafluoroethylene with chloromethane to obtain 1-chloro-1,1,2,2-tetrafluoropropane;
The 1-chloro-1,1,2,2-tetrafluoropropane obtained in the third step is contacted with the catalyst containing the metal fluoride to obtain a reaction product, and the obtained reaction product is The method for producing 2,3,3,3-tetrafluoropropene according to any one of claims 4 to 6, which is brought into contact with a catalyst containing the metal compound. The method for producing 2,3,3,3-tetrafluoropropene according to any one of claims 1 to 10, wherein the metal fluoride is at least one of aluminum fluoride and calcium fluoride. The method for producing 2,3,3,3-tetrafluoropropene according to any one of claims 1 to 11, wherein the metal fluoride is aluminum fluoride. A catalyst containing 3-chloro-2,3,3-trifluoropropene in the presence of hydrogen fluoride and containing at least one metal compound selected from metal oxides, metal oxide partial halides and metal halides; A method for producing 2,3,3,3-tetrafluoropropene, wherein 2,3,3,3-tetrafluoropropene is obtained by contact. The 2,3,3,3-tetrafluoropropene according to claim 13, wherein the metal compound comprises at least one selected from calcium fluoride, calcium fluoride partial fluoride, cobalt chloride, and cobalt chloride partial fluoride. Manufacturing method.

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