JP2016124847A - Method for producing trifluoroethylene - Google Patents

Abstract

Provided is a method for efficiently and economically producing 1-chloro-1,2-difluoroethylene by an industrially practicable method.
1-Chloro-1,2,2-trifluoroethane and / or 1-chloro-1,1,2-trifluoroethane is removed by contacting with an alkaline aqueous solution in the presence of a phase transfer catalyst. A method for producing trifluoroethylene by hydrogen chloride reaction.
[Selection figure] None

Description

  The present invention relates to a method for producing trifluoroethylene.

  In recent years, with the increase in greenhouse gas regulations, an alternative product having a lower global warming potential (GWP) has been demanded, and trifluoroethylene (HFO-1123) has attracted attention as a next-generation refrigerant. In the present specification, for halogenated hydrocarbons, the abbreviations of the compounds are described in parentheses after the compound names. In the present specification, the abbreviations are used instead of the compound names as necessary.

  HFO-1123 can be prepared by reacting chlorotrifluoroethylene (CFO-1113) with hydrogen in the presence of a hydrogenation catalyst, or 1,1,2-trichloro-1,2,2-trifluoroethane (CFC), for example. -113) is known to be produced by reaction with hydrogen in the presence of a catalyst.

  Since various by-products are generated in these production methods, it is industrially demanded to produce useful compounds by effectively using these by-products. In particular, in the reaction (reduction reaction) of CFO-1113 or CFC-113 with hydrogen, 1-chloro-1,2,2-trifluoroethane (HCFC-133) or 1-chloro-1,1,2- Hydrochlorofluoroalkane such as trifluoroethane (HCFC-133b) is by-produced. Effective utilization of these hydrochlorofluoroalkanes is required for efficient production of HFO-1123.

  Patent Document 1 proposes a method for producing a halogenated alkene by dehydrohalogenating a hydrochlorofluoroalkane in the presence of a high surface area metal fluoride or oxyfluoride. However, this method has a problem that not only the conversion rate of hydrochlorofluoroalkane is as low as 15% or less, but also the selectivity of halogenated alkene is low. Moreover, the dehydrohalogenation reaction described in Patent Document 1 is only a dehydrofluorination reaction, and it is considered difficult to apply this method to dehydrochlorination of hydrochlorofluoroalkanes.

Special table 2010-533151

  An object of this invention is to provide the method of manufacturing HFO-1123 efficiently and economically by the method which can be implemented industrially.

  The present invention provides a method for producing HFO-1123, which comprises subjecting HCFC-133 and / or HCFC-133b to a dehydrochlorination reaction by contacting with an alkaline aqueous solution in the presence of a phase transfer catalyst.

  According to the production method of the present invention, the conversion rate of raw materials and the selectivity of HFO-1123 are both high, and HFO-1123 can be produced efficiently and economically.

The method for producing HFO-1123 of the present invention is characterized in that HCFC-133 and / or HCFC-133b is used as a raw material, and this is dehydrochlorinated by contacting with an alkaline aqueous solution in the presence of a phase transfer catalyst. And
The reaction of HCFC-133 is a dehydrochlorination reaction represented by the following reaction formula (1). The reaction of HCFC-133b is a dehydrochlorination reaction represented by the following reaction formula (2).

  In the method for producing HFO-1123 of the present invention, the HCFC-133 and HCFC-133b used as raw materials are used when, for example, HFO-1123 is produced by reacting CFO-1113 with hydrogen in the presence of a catalyst. It is obtained as a by-product produced by the reaction of HFO-1123, which is a product, with hydrogen chloride.

……………………（３） In the method for producing HFO-1123 by the hydrogen reduction reaction of CFO-1113, the reaction shown in the reaction formula (3) is performed in the reactor.

…………………… (3)

  The ratio of CFO-1113 and hydrogen in the raw material composition is in the range of 0.01 to 4.0 moles of hydrogen with respect to 1 mole of CFO-1113. The pressure in the reactor is preferably normal pressure from the viewpoint of handleability. As the catalyst, a palladium catalyst is preferable, and the palladium catalyst is preferably supported on a support such as activated carbon. In order to perform a gas phase reaction, the temperature of the catalyst layer is preferably a temperature equal to or higher than the dew point of the raw material composition (mixed gas) containing CFO-1113 and hydrogen, and preferably in the range of 220 ° C to 240 ° C. The contact time between CFO-1113 and the catalyst is preferably 4 to 60 seconds.

In hydrogen reduction of CFO-1113, a composition containing HFO-1123 can be obtained as the outlet gas of the reactor. As compounds other than HFO-1123 contained in the outlet gas, in addition to CFO-1113 which is an unreacted raw material, (E) -1,2-difluoroethylene (HFO-1132 (E)), (Z)- 1,2-difluoroethylene (HFO-1132 (Z)), 1,1-difluoroethylene (HFO-1132a), 1-chloro-2,2-difluoroethylene (HCFO-1122), (E) -1-chloro -1,2-difluoroethylene (HCFO-1122a (E)), (Z) -1-chloro-1,2-difluoroethylene (HCFO-1122a (Z)), methane, 1,1-difluoroethane (HFC-152a ), 2-chloro-1,1-difluoroethane (HCFC-142), 1-chloro-1,1-difluoroethane (HCFC-142b), 1 Chloro-1,2,2-trifluoroethane (HCFC-133), 1-chloro-1,1,2-trifluoroethane (HCFC-133b), 1,2-dichloro-1,1,2-trifluoro Ethane (HCFC-123a), 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), 1,2-dichloro-1,2-difluoroethylene (CFO-1112), etc. Can be mentioned.
In addition, (E) -compound name or abbreviation (E) indicates that it is an E isomer of a geometric isomer, and (Z) -compound name or abbreviation (Z) indicates that it is a Z isomer.

By separating and purifying the crude product obtained by the hydrogen reduction reaction by a method such as distillation, HCFC-133 and HCFC-133b are obtained.
In the method for producing HFO-1123 of the present invention, HCFC-133 and / or HCFC-133b obtained as described above can be used as a raw material. In addition, the acquisition method of HCFC-133 and HCFC-133b used as a raw material is not limited to this.

  Hereinafter, the manufacturing method of HFO-1123 of this invention is further demonstrated.

<Manufacture of HFO-1123>
The method for producing HFO-1123 of the present invention uses HCFC-133 and / or HCFC-133b as a raw material, and in the presence of a phase transfer catalyst, as shown in the above reaction formulas (1) and / or (2). And dehydrochlorination reaction by contacting with an aqueous alkali solution.
As shown in the reaction formula (1), the reaction of dehydrochlorinating HCFC-133 with an aqueous alkali solution in the presence of a phase transfer catalyst is also referred to as reaction A below. Further, as shown in the reaction formula (2), the reaction in which HCFC-133b is dehydrochlorinated by contacting with an aqueous alkali solution in the presence of a phase transfer catalyst is also referred to as reaction B below.

(HCFC-133 and / or HCFC-133b)
As a raw material, one or both of HCFC-133 and HCFC-133b are used.
When using both HCFC-133 and HCFC-133b as a raw material, the content rate of HCFC-133 and HCFC-133b in a raw material composition is not specifically limited.

  In the manufacturing method of HFO-1123 of this invention, you may use the raw material composition which contains organic compounds other than HCFC-133 and HCFC-133b in the range which does not impair the effect of this invention. Specifically, by-products and unreacted raw materials in the reaction formula (3) can be mentioned. The content of organic compounds other than HCFC-133 and HCFC-133b is preferably less than 10% by mass with respect to the total amount of the raw material composition.

(Alkaline aqueous solution)
The alkaline aqueous solution used for the reaction A and the reaction B is not particularly limited as long as it is an aqueous solution of a basic compound in which a dehydrochlorination reaction proceeds. Specifically, inorganic basic compounds such as alkali metal hydroxides such as potassium hydroxide and sodium hydroxide, alkaline earth metal hydroxides such as calcium hydroxide, organic basic compounds such as amines, Examples include aqueous solutions of alkali metal alkoxides. Among these, an aqueous solution of an inorganic basic compound is preferable from the viewpoint of economy, and an aqueous solution of sodium hydroxide or potassium hydroxide is more preferable from the viewpoint of improving reaction activity and selectivity of HFO-1123.

  The concentration of the aqueous alkali solution is preferably 0.5 to 80% by mass and particularly preferably 5 to 50% by mass in both the reaction A and the reaction B from the point of promoting the dehydrochlorination reaction. In addition, the concentration of the aqueous alkali solution is 0 from the viewpoint of suppressing precipitation of a salt that is a by-product generated after the dehydrochlorination reaction, for example, metal chloride or metal fluoride generated when using a metal hydroxide. 0.5 to 50% by mass is preferable, and 0.5 to 20% by mass is particularly preferable.

  In addition, when using both HCFC-133 and HCFC-133b as a raw material, the reaction A and the reaction B occur independently, respectively. In each of the reaction A and the reaction B, the concentration of the alkaline aqueous solution is preferably within the above range. In this case, the concentration of the alkaline aqueous solution is preferably 0.5 to 80% by mass, and more preferably 5 to 50% by mass. . Moreover, from the point which suppresses precipitation of the salt which is a by-product which arises after the said dehydrochlorination reaction, the density | concentration of aqueous alkali solution has preferable 0.5-50 mass%, and 0.5-20 mass% is especially preferable. .

  The amount of the alkaline aqueous solution used is preferably 0.5 to 5.0 molar equivalents relative to the total amount of HCFC-133 and HCFC-133b as the total alkali amount in the alkaline aqueous solution, and 0.8 to 2.0 moles. The equivalent is more preferable, and 1.0 to 1.3 molar equivalent is particularly preferable.

(Phase transfer catalyst)
In the dehydrochlorination reaction, HCFC-133 and / or HCFC-133b and the alkaline aqueous solution are not compatible with each other. In addition, the reaction is carried out using a phase transfer catalyst that is soluble in a water-insoluble organic solvent.

  In the present invention, as the phase transfer catalyst used in the reaction A and the reaction B, a generally used phase transfer catalyst can be mentioned without particular limitation, and includes a quaternary ammonium salt, a quaternary phosphonium salt, and a quaternary arsonium. Salts, sulfonium salts, crown ethers and the like. Among these, a quaternary ammonium salt or a quaternary phosphonium salt is preferable.

  Specific examples of the quaternary ammonium salt include compounds represented by the following general formula (i) (hereinafter also referred to as compound (i)).

（ただし、式（ｉ）中、Ｒ^１１〜Ｒ^１４は、それぞれ独立して炭化水素基を表し、Ｙ⁻は、陰イオンを表す。）

(In the formula (i), R ^{11 to} R ¹⁴ each independently represents a hydrocarbon group, and Y ⁻ represents an anion.)

In the formula (i), R ^{11 to} R ¹⁴ representing a hydrocarbon group are more specifically the following groups. That is, examples of R ^{11 to} R ¹⁴ include an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, and an aryl group, and an alkyl group and an aryl group are preferable. The number of carbon atoms of R ¹¹ to R ¹⁴ is the total number of carbon atoms of ^R 11 ^{to R 14} per molecule, preferably 4 to 100. R ^{11 to} R ¹⁴ may be the same group or different groups.

R ^{11 to} R ¹⁴ may be substituted with a functional group that is inert under the reaction conditions. Examples of the inert functional group include a halogen atom, an ester group, a nitrile group, an acyl group, a carboxyl group, and an alkoxyl group, depending on the reaction conditions.

R ^{11 to} R ¹⁴ may be connected to each other to form a heterocyclic ring such as a nitrogen-containing heterocyclic ring. Furthermore, R ^{11 to} R ¹⁴ may be part of a polymer compound.

Specific examples of such quaternary ammonium ions having R ^{11 to} R ¹⁴ (R ¹¹ R ¹² R ¹³ R ¹⁴ N ⁺ ) include tetramethylammonium ion, tetraethylammonium ion, tetra-n-propylammonium ion, Tetra-n-butylammonium ion, tri-n-octylmethylammonium ion, cetyltrimethylammonium ion, benzyltrimethylammonium ion, benzyltriethylammonium ion, cetylbenzyldimethylammonium ion, cetylpyridinium ion, n-dodecylpyridinium ion, phenyltrimethyl Ammonium ion, phenyltriethylammonium ion, N-benzylpicolinium ion, pentamethonium ion, hexamethonium ion Etc.

In the formula (i), Y ⁻ representing an anion specifically includes chlorine ion, fluorine ion, bromine ion, iodine ion, sulfate ion, nitrate ion, phosphate ion, perchlorate ion, hydrogen sulfate. Examples include ions, hydroxide ions, acetate ions, benzoate ions, benzenesulfonate ions, p-toluenesulfonate ions, and preferred are chlorine ions, bromine ions, iodine ions, hydrogen sulfate ions, or hydroxide ions. For divalent or higher anions, the number of moles is adjusted so that the electric charge is balanced in formula (i).

Here, as a compound (i), the combination of following R ^{< 11 >} R ^{< 12 >} R ^{< 13 >} R ^{< 14 >} N ^<+> and the following Y ^{< - >} is preferable from the point of the versatility and reaction activity of a compound (i).

R ¹¹ R ¹² R ¹³ R ¹⁴ N ⁺ : Tetramethylammonium ion, tetraethylammonium ion, tetra-n-propylammonium ion, tetra-n-butylammonium ion or tri-n-octylmethylammonium ion.
Y ⁻ : Fluorine ion, chlorine ion or bromine ion.

  Specific examples of the quaternary phosphonium salt include compounds represented by the following general formula (ii) (hereinafter also referred to as compound (ii)).

（ただし、式（ii）中、Ｒ^２１〜Ｒ^２４は、それぞれ独立して炭化水素基を表し、Ｙ⁻は、陰イオンを表す。）

(However, in formula (ii), R ^{21 to} R ²⁴ each independently represent a hydrocarbon group, and Y ⁻ represents an anion.)

In the general formula (ii), R ^{21 to} R ²⁴ representing a hydrocarbon group are more specifically groups having the following characteristics.

Examples of R ^{21 to} R ²⁴ include an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, and an aryl group, and an alkyl group and an aryl group are preferable.
The number of carbon atoms of R ²¹ to R ^{24 are} as ^{R 21 R 22 R 23 R 24} P + total number of carbon atoms per molecule, preferably 4 to 100.

R ^{21 to} R ²⁴ may be the same group or different groups.
R ^{21 to} R ²⁴ may be substituted with a functional group that is inert under the reaction conditions. Examples of the inert functional group include a halogen atom, an ester group, a nitrile group, an acyl group, a carboxyl group, and an alkoxyl group, depending on the reaction conditions.

Specific examples of the quaternary phosphonium ion R ²¹ R ²² R ²³ R ²⁴ P ⁺ having R ^{21 to} R ²⁴ include tetraethylphosphonium ion, tetra-n-butylphosphonium ion, and tri-n-octylethylphosphonium. Ion, cetyltriethylphosphonium ion, cetyltri-n-butylphosphonium ion, n-butyltriphenylphosphonium ion, n-amyltriphenylphosphonium ion, methyltriphenylphosphonium ion, benzyltriphenylphosphonium ion, tetraphenylphosphonium ion, etc. It is done.

In the general formula (ii), as Y ⁻ representing an anion, specifically, chlorine ion, fluorine ion, bromine ion, iodine ion, sulfate ion, nitrate ion, phosphate ion, perchlorate ion, sulfuric acid Examples thereof include a hydrogen ion, a hydroxide ion, an acetate ion, a benzoate ion, a benzenesulfonate ion, a p-toluenesulfonate ion, and a fluorine ion, a chlorine ion, or a bromine ion is preferable.

  Specific examples of the phase transfer catalyst include tetramethylammonium chloride, tetraethylammonium bromide, tetra-n-propylammonium bromide, tetra-n-butylammonium bromide, tri-n-octylmethylammonium chloride, cetyltrimethylammonium bromide, benzyltrimethyl Ammonium chloride and the like can be mentioned, among which tetra-n-butylammonium bromide is preferable from the viewpoint of economy and safety.

  The amount of the phase transfer catalyst is preferably 0.001 to 10 parts by mass (0.001 to 10% by mass) with respect to a total of 100 parts by mass of HCFC-133 and HCFC-133b in the raw material used. -5 mass parts (0.1-5 mass%) is more preferable.

(Dehydrochlorination reaction)
Specifically, the reaction A and / or the reaction B is carried out by introducing HCFC-133 and / or HCFC-133b, the alkaline aqueous solution, and the phase transfer catalyst into the reactor at the above ratios, and sufficiently contacting them. Thus, it is carried out by performing stirring or the like by ordinary means.

The temperature of the dehydrochlorination reaction (also referred to as the reactor internal temperature) is not particularly limited, but is preferably 40 to 200 ° C, and preferably 70 to 200 ° C from the viewpoint of improving the conversion rate of HCFC-133 and / or HCFC-133b. Is more preferable. From the viewpoint of high selectivity of HFO-1123 which is the target product, 40 to 150 ° C is preferable, and 40 to 130 ° C is more preferable.
In order to carry out the reaction in the liquid phase, the reaction pressure is adjusted to a state where HCFC-133 and HCFC-133b are liquefied at the reaction temperature, that is, the saturated vapor pressure or higher. Specifically, the reaction pressure at the reaction temperature is preferably 0.2 to 3 MPa as a gauge pressure.
The dehydrochlorination reaction is preferably carried out in a pressurized reaction vessel, and the gas produced by the reaction is preferably recovered via a pressure regulating valve. In order to avoid the unreacted raw material HCFC-133 and / or HCFC-133b being included in the gas recovered via the pressure regulating valve, a packed tower and a condenser are connected to the pressurized reaction vessel. It is preferable to concentrate and distill the low boiling point component of the gas at the top of the packed column, that is, to perform reactive distillation.
Moreover, when reacting by pressurization, after completion | finish of reaction, a reaction liquid can be separated into an organic phase and an aqueous phase naturally. This organic phase may be extracted and recovered.

  Reaction A and reaction B are carried out in one reactor. These reactions can be carried out by any of the semi-continuous, batch, and continuous flow systems, and the reaction time can be appropriately adjusted by an ordinary method according to each system. When both HCFC-133 and HCFC-133b are used as raw materials, HCFC-133 and HCFC-133b can be separately supplied to the reactor. It is preferable to supply to the reactor.

  The material of the reactor is not particularly limited as long as the material is inert to the reaction liquid components including the raw material, the phase transfer catalyst, the alkaline aqueous solution, and the reaction product and is corrosion resistant. Specific examples of such a reactor material include glass, iron, nickel, and alloys containing these as main components. Stainless steel is particularly preferred.

  In the production method of the present invention, in addition to HFO-1123 which is the target product and HCFC-133 and / or HCFC-133b which are unreacted raw materials, a by-product (hereinafter referred to as by-product C) may be included.

  Examples of the by-product C contained in the recovered gas component or the organic phase include HCFO-1122, HCFO-1122a (E), and HCFO-1122a (Z).

  The obtained HFO-1123, HCFC-133 and / or HCFC-133b as unreacted raw materials, HCFO-1122, HCFO-1122 (E) and HCFO-1122 (Z) as by-products have an appropriate boiling point difference. It can be separated and purified by general distillation or the like. The separated and purified HFO-1123 can be used for various applications.

  As described above, the method for producing HFO-1123 of the present invention can be industrially implemented, the reaction conditions are mild, and the production of by-products can be suppressed. Both the raw material conversion ratio and the HFO-1123 selectivity are high, and this is an efficient and economical production method.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

<Manufacture of HCFC-133 and HCFC-133b>
Raw materials HCFC-133 and HCFC-133b were produced. The following production examples are examples of production of HCFC-133 and / or HCFC-133b according to the reaction formula (3).

[Production Example 1]
A stainless steel reaction tube having an inner diameter of 2.3 cm and a length of 50 cm is filled with palladium-supported activated carbon in which 0.5 parts by weight of palladium is loaded with respect to 100 parts by weight of coconut shell activated carbon. A layer was formed.

  The catalyst layer in the reaction tube thus formed was controlled at 80 ° C. by an electric heater, and the raw material composition having an internal pressure of 0.04 MPa and a molar ratio of CFO-1113 to hydrogen of 1.0 was used as the raw material composition with respect to the catalyst layer. Was supplied to the reaction tube so that the contact time was 30 seconds to produce HFO-1123. At this time, the maximum temperature of the catalyst layer was 236 ° C. The manufacturing conditions at this time are shown in Table 1.

  Next, the product gas discharged from the outlet of the reaction tube was subjected to alkali cleaning and then dehydrated to recover crude HFO-1123. The recovered crude HFO-1123 was analyzed by gas chromatography (hereinafter referred to as GC), and the molar composition of each component was determined from the peak area ratio of GC. Production conditions and product composition are shown in the lower column of Table 1.

  Next, HCFC-133 and HCFC-133b were obtained separately by distilling the crude HFO-1123 by a known method.

<Manufacture of HFO-1123>
HFO-1123 was produced using the HCFC-133 and / or HCFC-133b obtained above.

Example 1
After charging 41.6 g (0.35 mol) of HCFC-133b into a stainless steel reaction vessel having an internal volume of 1000 mL, 410 mg of tetra-n-butylammonium chloride (TBAC) as a phase transfer catalyst (relative to HCFC-133b) 1.0 mass%) and 50.2 g of potassium hydroxide aqueous solution (40 mass%) (20.1 g (0.36 mol) as potassium hydroxide) were added to the reaction vessel. The temperature in the reactor was controlled at a set temperature of 45 ° C. using a thermostatic bath, and the reaction was carried out for 24 hours while stirring. The pressure in the reactor was 0.25 MPa when the temperature in the reactor before starting the reaction was 45 ° C., and 0.3 MPa after 24 hours from the start of the reaction. After 24 hours from the start of the reaction, the crude product remaining in the reactor was recovered, and the composition of the recovered crude product was analyzed by GC.

  In the GC analysis, the molar composition of each component was determined from the GC peak area ratio, and the conversion rate of HCFC-133b was determined from the determined molar composition of each component.

"Conversion rate" was calculated as (100-X)% as the conversion rate of HCFC-133b when the molar composition of HCFC-133b in the crude product calculated from GC was X%.
Further, the “selectivity” indicating the percentage of each reacted HCFC-133b converted to each component other than HCFC-133b was calculated by the following equation.
Selectivity of each component = molar composition of each component / conversion rate of HCFC-133b Table 2 shows the results of GC analysis of the crude product together with the production conditions.

Example 2
41.8 g (0.35 mol) of HCFC-133b, 409 mg of TBAC (1.0% by mass with respect to HCFC-133b), and 50.5 g of aqueous potassium hydroxide (40%) were used. The reaction was carried out for 24 hours under the same conditions as in Example 1 except that the temperature was controlled at 75 ° C. The pressure inside the reactor was 0.67 MPa when the temperature in the reactor before starting the reaction was 75 ° C., and 0.73 MPa after 24 hours from the start of the reaction. After 24 hours from the start of the reaction, the crude product remaining in the reactor was collected, and the composition of the collected crude product was analyzed by GC in the same manner as in Example 1. The analysis results are shown in Table 2 together with the production conditions.

Example 3
41.6 g (0.35 mol) of HCFC-133b, 412 mg of TBAC (1.0% by mass with respect to HCFC-133b) and 50.1 g of aqueous potassium hydroxide (40%) were used. The reaction was carried out for 12 hours under the same conditions as in Example 1 except that was controlled at a set temperature of 100 ° C. The pressure in the reactor was 1.10 MPa when the temperature in the reactor before the start of the reaction was 100 ° C., and 1.50 MPa after 12 hours from the start of the reaction. After 12 hours from the start of the reaction, the crude product remaining in the reactor was recovered, and the composition of the recovered crude product was analyzed by GC in the same manner as in Example 1. The analysis results are shown in Table 2 together with the production conditions.

Example 4
After charging 7.9 g (0.067 mol) of HCFC-133 into a stainless steel reaction vessel having an internal volume of 200 mL, 237 mg of TBAC (3.0 mass% with respect to HCFC-133) and an aqueous potassium hydroxide solution ( 40% by mass) of 10.3 g (4.1 g (0.07 mol) as potassium hydroxide) was added to the reaction vessel. The temperature inside the reactor was controlled at a set temperature of 76 ° C. using a thermostatic bath, and the reaction was carried out for 24 hours while stirring. The pressure in the reactor was 0.35 MPa when the temperature in the reactor before the start of the reaction was 76 ° C., and 0.75 MPa after 24 hours from the start of the reaction. After 24 hours from the start of the reaction, the crude product remaining in the reactor was recovered, and the composition of the recovered crude product was analyzed by GC.

  In GC analysis of Examples 2-4, the molar composition of each component was calculated | required from the peak area ratio of GC, respectively, and the conversion rate of HCFC-133 and the selectivity of each component were calculated | required from the calculated | required molar composition of each component. Calculated.

The "conversion rate of HCFC-133" was calculated as (100-Y)% conversion rate of HCFC-133 when the molar composition of HCFC-133 in the crude product calculated from GC was Y%. . Then, “selectivity of each component” was calculated by the following formula.
Selectivity of each component = molar composition of each component / conversion rate of HCFC-133 Table 3 shows the results of GC analysis of the crude product in Example 4 together with the production conditions.

Example 5
10.4 g (HCFC-133b; 7.5 g and HCFC-133; 2.9 g) of a mixture having a weight ratio of HCFC-133b and HCFC-133 of 72/28 was charged into a 200 mL stainless steel reaction vessel. Thereafter, 316 mg of TBAC (3.0% by mass with respect to HCFC-133b) and 12.7 g of potassium hydroxide aqueous solution (40% by mass) (5.1 g (0.09 mol) as potassium hydroxide) were mixed. The solution was added to the reaction vessel. The temperature in the reactor was controlled at a set temperature of 100 ° C. using a thermostatic bath, and the reaction was carried out for 12 hours while stirring. The pressure in the reactor was 0.98 MPa when the temperature in the reactor before the start of the reaction was 100 ° C., and 1.20 MPa after 12 hours from the start of the reaction. 12 hours after the start of the reaction, the crude product remaining in the reactor was recovered, and the composition of the recovered crude product was analyzed by GC.

  In the GC analysis, the molar composition of each component was determined from the peak area ratio of GC. And from the calculated | required molar composition of each component, the conversion rate of HCFC-133b, the conversion rate of HCFC-133, and the total conversion rate of HCFC-133b and HCFC-133 were computed. Moreover, the selectivity of each component other than HCFC-133b and HCFC-133 was calculated from the obtained molar composition of each component.

“Total conversion rate” is (100−Z)% when the sum of the molar composition of HCFC-133b and the molar composition of HCFC-133 in the crude product is Z%, and HCFC-133b and HCFC-133 The total conversion was calculated as the conversion rate.
The “conversion rate of HCFC-133b” was calculated as {(72−Z1) / 72} × 100% conversion rate of HCFC-133b when the molar composition of HCFC-133b was Z1%. The “conversion rate of HCFC-133” was calculated as {conversion rate of HCFC-133} when the molar composition of HCFC-133 was Z 2%, {(28−Z 2) / 28} × 100%. Then, “selectivity of each component” was calculated by the following formula.
Selectivity of each component = molar composition of each component / (conversion rate in total of HCFC-133b and HCFC-133)
The results of GC analysis of the crude product are shown in Table 4 together with the production conditions.

  According to the production method of the present invention, HFO-1123 useful as a refrigerant or the like can be produced efficiently and economically by an industrially feasible method.

Claims (4)

  1-Chloro-1,2,2-trifluoroethane and / or 1-chloro-1,1,2-trifluoroethane is dehydrochlorinated by contacting with an aqueous alkali solution in the presence of a phase transfer catalyst. A process for producing trifluoroethylene characterized by the above.   The 1-chloro-1,2,2-trifluoroethane and / or the 1-chloro-1,1,2-trifluoroethane is chlorotrifluoroethylene or 1,1,2-trichloro-1,2, The method for producing trifluoroethylene according to claim 1, which is obtained by reacting 2-trifluoroethane with hydrogen in the presence of a catalyst.   The manufacturing method of the trifluoroethylene of Claim 1 or 2 whose density | concentration of the said aqueous alkali solution is 0.5 mass%-80 mass%.   The method for producing trifluoroethylene according to any one of claims 1 to 3, wherein a temperature of the dehydrochlorination reaction is 40 to 200 ° C.