JPH08169850A - Production of 1,1,1,2,3,3-hexafluoropropane - Google Patents

Abstract

PURPOSE: To obtain the subject compound, useful as an alternative to compounds to be used as a foaming agent or cooling medium from an inexpensive raw material, by subjecting a propane compound to fluoric acid removal followed by fluorinating the product with fluoric anhydride and then reduction with hydrogen. CONSTITUTION: A propane compound of the formula XCF2 CF2 CHClY (X and Y are each F or Cl) is subjected to fluoric acid removal with an aqueous alkali solution (e.g. KOH) in a solvent (e.g. water) to form a propane compound of the formula XCF2 CF=CClY, which is then fluorinated with fluoric anhydride in a liquid phase in the presence of an antimony catalyst (e.g. antimony pentafluoride) to produce 1,1,1,2,3,3-hexafluoro-3-chloropropane, which is, in turn, reduced with hydrogen in the presence of a noble metal catalyst (e.g. Pd carried on carbon) at 100-350 deg.C to obtain the objective compound in a yield of as high as >=95%. By this multistage production process, the objective compound can be obtained economically without the need of using expensive hexafluoropropane as a raw material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for producing 1,1,1,2,3,3-hexafluoropropane which can be used as a substitute for a CFC compound or an HCFC compound used as a foaming agent or a refrigerant (particularly, Multi-step manufacturing method).

[0002]

2. Description of the Related Art As a method for producing 1,1,1,2,3,3-hexafluoropropane, a method of hydrogenating hexafluoropropene using a Pd catalyst is known. Fluoropropene is relatively expensive and is not an economical method.

[0003]

The object of the present invention is to provide 1,1,1,2,3,3-hexafluoropropane which can be a substitute for CFC compounds and HCFC compounds with low cost and high selectivity. It is to provide a method that can be manufactured.

[0004]

Means for Solving the Problems The present inventor diligently studied a method for producing 1,1,1,2,3,3-hexafluoropropane in order to solve the above-mentioned problems, and as a result, the following production method was obtained. Therefore, if 1,1,1,2,3,3-hexafluoropropane is produced in a multi-step manner, it can be produced without using expensive hexafluoropropene as a raw material, so that it is economical. That is, the present invention has been completed.

That is, the present invention eliminates a propane compound represented by the general formula (1): XCF ₂ CF ₂ CHClY (wherein X and Y are each a fluorine atom or a chlorine atom). Hydrofluoric acid is used to obtain a propene compound represented by the general formula (2): XCF ₂ CF = CClY (wherein X and Y are the same as those described above).
Step, and fluorinating this propene compound in the liquid phase in the presence of an antimony catalyst with hydrofluoric anhydride,
The second step of obtaining 1,2,3,3-hexafluoro-3-chloropropane and hydrogen reduction of this 1,1,1,2,3,3-hexafluoro-3-chloropropane in the presence of a noble metal catalyst. , 1,1,1,2,3,3-the third step of obtaining hexafluoropropane, 1,1,1,
The present invention relates to a multistep production method of 2,3,3-hexafluoropropane.

In the production method of the present invention, the first step, general formula (1): XCF ₂ CF ₂ CHClY (X, Y
Defluorinate a propane compound represented by F or Cl) to obtain a compound represented by the general formula (2): XCF ₂ CF = CClY
The process for obtaining the propene compound represented by (where X and Y are the same as those in formula (1)) will be described.

The raw material XCF ₂ CF ₂ CHClY
Examples of the propane compound represented by (X and Y are F or Cl) are 1,1,1,2,2,3-hexafluoro-3-chloropropane (hereinafter referred to as HCFC-226ca).
Called. ), 1,1,1,2,2-pentafluoro-
3,3-Dichloropropane (hereinafter HCFC-225c
It is called a. ), 1,1,2,2,3-pentafluoro-1,3-dichloropropane (hereinafter referred to as HCFC-225
It is called cb. ), 1,1,2,2-tetrafluoro-
1,3,3-Trichloropropane (hereinafter HCFC-2
24ca. ).

HCFC-226ca is equivalent to HCFC-22
It can be obtained by fluorinating 5ca or 225cb with hydrofluoric acid anhydride in the presence of a catalyst such as chromium. HCFC-2
25ca and HCFC-225cb are tetrafluoroethylene and fluorodichloromethane, and HCFC-
224ca is a raw material that can be easily produced by reacting tetrafluoroethylene and chloroform in the presence of a Lewis acid catalyst such as aluminum chloride.

(Dehydrofluoric Acid in Liquid Phase) The dehydrofluoric acid reaction from these compounds is carried out by KOH, NaOH, Ca (OH) ₂
It is possible to use an inorganic basic compound such as an alkali metal hydroxide, an alkaline earth metal hydroxide or the like, an organic basic compound such as an amine, an alkali metal alkoxide, etc. It is preferable to use a basic compound. As the solvent for the hydrofluoric acid reaction, water, alcohols such as methanol, ethers such as dibutyl ether, and the like can be used, but it is preferable to use water as the solvent from the viewpoints of product recovery and economy. .

When carrying out the dehydrofluoric acid reaction using calcium hydroxide, an aqueous solution or a slurry formed by mixing water and calcium hydroxide may be used. Further, at this time, it may be used by mixing with potassium hydroxide.
An advantage of using calcium hydroxide is that calcium fluoride produced by dehydrofluoric acid can be reused as a raw material for hydrofluoric acid.

When the dehydrofluoric acid reaction is carried out in an aqueous solution, it is possible to use a phase transfer catalyst such as a quaternary ammonium salt, a phosphonium salt or a crown ether in order to allow the reaction to proceed smoothly.

As the cation of the quaternary ammonium salt, benzyltriethylammonium, trioctylmethylammonium, tricaprylmethylammonium,
Tetrabutylammonium etc. are mentioned. Examples of the cation of the quaternary phosphonium salt include tetrabutylphosphonium and trioctylethylphosphonium. The anion that forms a salt with those cations is not limited, but generally, chloride ion, bromine ion, hydrogensulfate ion and the like can be mentioned. Examples of crown ethers include 18-crown-6 and dibenzo-18-crown-6. However, the above is merely an example and does not limit the type of the phase transfer catalyst.

These aqueous solutions can be reused by adding the alkali again after separating the fluoride formed after the reaction by a precipitation method, a filtration method or the like.

The reaction temperature is not particularly limited, but is 30 to 150.
It can be carried out in the range of ° C. For example, in the case of HCFC-226ca, which is a compound having a low boiling point, it can be carried out in a pressurized reaction vessel.

(Dehydrofluoric Acid in Gas Phase) The dehydrofluoric acid reaction can also be carried out by a gas phase reaction using a metal oxide as a catalyst, and as the metal oxide, chlorides of Fe, Cr and Cu, sulfates, It can be obtained by adding an aqueous ammonia solution which is an alkali or an alkali metal hydroxide or urea to an aqueous solution of a nitrate, and heating the resulting metal hydroxide to obtain a metal hydroxide. In the case of chromium, it can be prepared by reducing hexavalent chromium.

These metal oxides may be used alone, or may be a composite oxide or a mixed oxide of a plurality of metals selected from these metals (Fe, Cr, Cu).

In the case of chromium oxide, it is possible to use a partially fluorinated oxide, which is usually fluorinated at 20 to 450 ° C, preferably 200 to 400 ° C. However, hydrofluoric acid anhydride may be used, or heat treatment with a fluorinated hydrocarbon may be used. Further, the partially fluorinated oxide of chromium can also be obtained by subjecting a hydrate of chromium trifluoride to oxygen treatment.

These metal oxides may be granulated or compressed into pellets. In addition, these may be supported on a carrier that does not directly participate in the reaction, such as aluminum fluoride or silica gel. In order to prevent the deterioration of the catalyst, oxygen, air, etc. may be circulated at the same time as the raw materials.

The dehydrofluoric acid reaction can also be carried out by a gas phase reaction using activated carbon as a catalyst. The type of activated carbon is not limited, but granular activated carbon, coconut shell activated carbon, etc. are preferably used.

The reaction temperature of the gas phase reaction is 200 to 600
℃ is good, more preferably in the range of 250 ~ 500 ℃.

As a method of the gas phase reaction, a method using a fixed bed type flow reactor or a fluidized bed type flow reactor can be adopted.

In the production method of the present invention, the propene compound represented by the general formula (2): XCF ₂ CF = CClY (X and Y are the same as those in the general formula (1)), which is the second step, is liquid. A method for obtaining 1,1,1,2,3,3-hexafluoro-3-chloropropane (hereinafter, referred to as HCFC-226ea) by fluorinating with antimony as a catalyst in the phase with hydrofluoric acid will be described.

In the present invention, it is particularly important to carry out the reaction by a liquid phase method using an antimony catalyst. As the antimony catalyst, antimony fluorochloride obtained by fluorinating antimony pentachloride and antimony trichloride can be used as a catalyst, but when chlorine is present on the catalyst,
Since the chlorination of the propene compound represented by the general formula (2) may proceed and the selectivity of the reaction may be lowered, the completely fluorinated antimony pentafluoride, 3
It is preferable to use antimony fluoride as a catalyst.

The pentavalent antimony halide (for example, antimony pentafluoride) and the trivalent antimony halide (for example, antimony trifluoride) can be used alone or in combination.

Although a solvent is not particularly required in the present invention, it is possible to use anhydrous HF which is a reactant as a solvent. A reaction solvent can be used if necessary, and any solvent that is inert to the catalyst can be used as the solvent. For example, perfluorohexane,
Perfluoro compounds such as perfluorodecalin and perfluorotributylamine may be mentioned.

When antimony pentafluoride is used as a catalyst and anhydrous HF is used as a reaction solvent, the concentration of the antimony catalyst may be limited depending on the material of the reaction vessel because of its strong corrosiveness. The concentration of the catalyst is not limited in the case of a fluororesin reaction vessel, but the catalyst concentration is limited in the case of a reaction vessel such as Hastelloy C22 which is a food resistant material. When only antimony pentafluoride is used as a catalyst, 1 mol% or less, more preferably 0.5 mol% or less, with respect to anhydrous HF, is preferable from the viewpoint of corrosion.

When antimony pentafluoride and antimony trifluoride are mixed and used, the mixing molar ratio is antimony pentafluoride / antimony trifluoride ≦ 2, more preferably antimony pentafluoride / 3 antimony trifluoride. ≦ 1, mixed antimony pentafluoride concentration is 1 relative to anhydrous HF
It is preferably 0 mol% or less, more preferably 3 mol% or less from the viewpoint of corrosion.

When only antimony trifluoride is used as the catalyst and anhydrous HF is used as the reaction solvent, the concentration of the catalyst is not limited because the corrosiveness is very small.

In order to avoid the problem of corrosiveness, HCFC-226e produced by charging a propene compound represented by the general formula (2) and anhydrous HF into antimony pentafluoride.
A reaction form in which a and unreacted anhydrous HF or / and the propene compound represented by the general formula (2) are extracted out of the reaction system and anhydrous HF does not accumulate in the reaction system can also be adopted in the present invention. .

The reaction temperature is not particularly limited, but is 25 to 150.
C., more preferably 40 to 100.degree.

The reaction pressure is also not particularly limited, but is from atmospheric pressure to 50 kg / cm ² G, more preferably from atmospheric pressure to 30 kg / cm ² G.
Can be adopted.

The molar ratio of the propene compound represented by the general formula (2) to anhydrous HF can be arbitrarily changed, but in order to increase the selectivity of the reaction, HF / propene compound = 4 or more is preferable. In this case, unreacted HF is HCFC-
In some cases, it may come out of the reaction system together with 226ea, but even at this time, HF can be recycled to the reaction system after separation.

The reaction can be carried out in a batch system in which the necessary raw materials are charged and then the reaction is carried out to recover the products and the like. One raw material is continuously charged and the products and the like are continuously extracted. A semi-batch method, a method of continuously charging raw materials and continuously withdrawing products and the like can be adopted.

In the production method of the present invention, the third step, 1,1,1,2,3,3-hexafluoro-3-chloropropane (HCFC-226ea) is hydrogenated in the presence of a noble metal catalyst. A method for obtaining 1,1,1,2,3,3-hexafluoropropane will be described.

That is, in this third stage, 1, 1, 1,
2,3,3-hexafluoro-3-chloropropane (H
CFC-226ea) is used as a raw material and 1 equivalent or more of hydrogen is used with respect to this raw material in the presence of a noble metal catalyst.
By carrying out the hydrogen reduction reaction at a temperature of ~ 350 ° C,
1,1,1,2,3,3-hexafluoropropane can be produced with a high yield of 95% or more.

In this case, a gas phase reaction is carried out. As this method, a fixed bed type gas phase reaction, a fluidized bed type gas phase reaction or the like can be adopted.

As the usable noble metal catalyst, it is possible to use a catalyst composed of at least one selected from palladium, platinum and rhodium, and a palladium catalyst is particularly preferable.

This noble metal catalyst is preferably supported on at least one carrier selected from activated carbon, alumina, silica gel, titanium oxide and zirconia, and the particle size of the carrier has little influence on the reaction. However, it is preferably 0.1 to 100 mm.

The supported concentration of the noble metal catalyst is 0.05 to 10%
A wide range of products can be used, but 0.5 to 5% supported products are usually recommended.

Further, the reaction temperature is usually 100 to 350 ° C., the conversion rate is apt to decrease remarkably at a reaction temperature of less than 100 ° C., and a by-product is produced at a reaction temperature of 350 ° C. or higher,
The equipment used for the reaction is easily damaged. The reaction temperature of this reaction is preferably 150 to 300 ° C.

In the hydrogen reduction reaction of 1,1,1,2,3,3-hexafluoro-3-chloropropane (HCFC-226ea), the ratio of hydrogen to the raw material is that hydrogen is 1,
If it is 1 equivalent or more with respect to 1,1,2,3,3-hexafluoro-3-chloropropane (HCFC-226ea), it can be significantly varied. However, hydrogenation is usually carried out using 2 to 5 times the stoichiometric amount of hydrogen. Much more than stoichiometric amount, based on the total moles of starting material,
For example, 10 moles or more of hydrogen may be used. Excess hydrogen can be recovered and reused.

The reaction pressure is not particularly limited, and it can be carried out under pressure, under reduced pressure, or under normal pressure. However, since the apparatus becomes complicated under reduced pressure, it is preferable to carry out the reaction under pressure or under normal pressure.

The contact time is usually 0.1 to 300 seconds, especially 1 to 30 seconds.

[0044]

According to the present invention, the dehydrofluoric acid of the propane compound represented by the general formula (1), the fluorination of the propene compound represented by the general formula (2) with the dehydrofluoric acid, and the hydrogen reduction of the fluorinated compound are carried out. By the stepwise process, it is possible to produce 1,1,1,2,3,3-hexafluoropropane, which can be a substitute for the CFC compound or the HCFC compound, from an inexpensive raw material, and use expensive hexafluoropropene as a raw material. It is economical because it does not.

[0045]

EXAMPLES The present invention will be described in more detail below with reference to examples.

(Dehydrofluoric acid) Example 1 1,1,1,2,2-pentafluoro-3,3 was placed in a 200 ml glass reaction vessel equipped with a dropping funnel and a condenser.
-Dichloropropane (HCFC-225ca) 40.7
g and tetrabutylammonium bromide 0.5 g were charged and stirred at room temperature.

An aqueous solution prepared by dissolving 16.8 g of potassium hydroxide in 50 ml of water was added dropwise from a dropping funnel so that the reaction temperature was kept at 30 ° C.

After the completion of dropping, the reaction was continued for another 2 hours,
When the organic layer was separated and analyzed by gas chromatography, the conversion of HCFC-225ca was 100%, and 1,1,1,2-tetrafluoro-3,3-dichloropropene had a selectivity of 98%. Was being generated. When this organic layer was dried over calcium chloride and then distilled,
The boiling point of 1,1,2-tetrafluoro-3,3-dichloropropene was 46 ° C.

Example 2 In a 200 ml glass reaction vessel equipped with a condenser,
1,2,2,3-Pentafluoro-1,3-dichloropropane (HCFC-225cb) 40.7 g, methyltrioctyl ammonium chloride 0.5 g, potassium hydroxide
An aqueous solution prepared by dissolving 16.8 g in 50 ml of water was charged.

The reaction was carried out at 55 ° C. with stirring, and after reacting for 10 hours, the same analysis as above showed that HCFC-225
The conversion rate of cb was 15%, and 1,1,2,3-tetrafluoro-1,3-dichloropropene was produced at a selectivity of 98%.

Example 3 A 200 ml glass reaction vessel equipped with a dropping funnel and a condenser was charged with an aqueous solution prepared by dissolving 16.8 g of potassium hydroxide in 50 ml of water and 0.5 g of tetrabutylammonium bromide, and stirred at 40 ° C.

From the dropping funnel, 1,1,2,2-tetrafluoro-1,3,3-trichloropropane (HCFC
-224ca) 43.9 g was added dropwise so that the reaction temperature was kept at 40 ° C.

After the completion of dropping, the reaction was continued for another 4 hours,
When the organic layer was separated and analyzed by gas chromatography, the conversion of HCFC-224ca was 99%, and the selectivity of 1,1,2-trifluoro-1,3,3-trichloropropene of interest was 96. %Met.

Example 4 16.8 of potassium hydroxide was added to an autoclave made of SUS316.
An aqueous solution prepared by dissolving 50 g of water in 50 ml of water and 0.5 g of tetrabutylammonium bromide were charged and cooled to -20 ° C.

After cooling, 1,1,1,2,2,3-hexafluoro-3-chloropropane (HCFC-226c
a) 37.3 g was placed in an autoclave and returned to room temperature.
Stirring was started, the reactor internal temperature was kept at 80 ° C., and the reaction was carried out for 8 hours. After the reaction was completed, the product was collected in a trap cooled to −70 ° C. initially at atmospheric pressure and then under reduced pressure.

When the collected organic matter was analyzed by gas chromatography, the conversion of HCFC-226ca was 20%, and the target 1,1,1,2-tetrafluoro-3-chloropropene-2 had a selectivity of It was 96%.

Example 5 Chromium hydroxide prepared from an aqueous solution of chromium nitrate and aqueous ammonia was filtered off, washed with water and dried at 100 ° C., and this was molded into a cylindrical shape having a diameter of 3 mm and a height of 3 mm using a tabletting machine. did.

The catalyst thus obtained was treated with Hastelloy C before the reaction.
The reaction tube was filled, and heated and kept at 400 ° C. for 1 hour under a nitrogen stream. Then, the temperature was lowered to 200 ° C., and hydrofluoric acid anhydride was supplied and treated for 1 hour for activation.

A Hastelloy C reaction tube having an inner diameter of 2 cm and a length of 40 cm was charged with the catalyst (20 g) prepared as described above,
It was heated to 350 ° C in an electric furnace while circulating nitrogen gas. Change nitrogen to HCFC-225ca (57cc / min),
Oxygen (3 cc / min) was entrained and passed through the reaction tube.

The reaction tube outlet gas was washed with water, dried over calcium chloride, and analyzed by gas chromatography. One hour after the start of the reaction, the conversion rate of HCFC-225ca was 70% and the selectivity of the target 1,1,1,2-tetrafluoro-3,3-dichloropropene-2 was 85%.

Example 6 A reaction was carried out in the same manner as in Example 5 except that a copper oxide-chromia composite oxide was used as a catalyst. H 1 hour after the start of reaction
The conversion rate of CFC-225ca is 52%.
The selectivity for 1,1,2-tetrafluoro-3,3-dichloropropene-2 was 83%.

Example 7 The reaction was performed in the same manner as in Example 1 except that iron oxide was used as the catalyst. The conversion rate of HCFC-225ca one hour after the start of the reaction was 33%, and the selectivity of the target 1,1,1,2-tetrafluoro-3,3-dichloropropene-2 was 86%.

(Fluorination) Example 8 S was added to a Hastelloy C22 autoclave with an internal volume of 200 ml.
bF ₅ 2.0g was prepared. After cooling the autoclave to -30 ° C, 50 g of anhydrous HF, 1,1,1, obtained in Example 1 above
2-tetrafluoro-3,3-dichloropropene 20 g
After charging, the mixture was returned to room temperature and the reaction was continued at 80 ° C. for 10 hours while stirring. The reaction pressure was kept at 12 kg / cm ² while removing HCl generated at this time to the outside of the system.

The reaction product was collected from the autoclave in a trap cooled to -70 ° C while removing HF with a water washing tower and an alkaline water tower. The collected organic matter was analyzed by gas chromatography.

As a result of the analysis, the conversion of 1,1,1,2-tetrafluoro-3,3-dichloropropene was 99%,
The selectivity of 1,1,2,3,3-hexafluoro-3-chloropropane (HCFC-226ea) was 99.9% or more.

[0066] Instead of the catalyst to SbF ₅ in Example 9 Example 8, SbF ₅ 5.4 g
And 8.9 g of SbF ₃ were charged and the same reaction was performed.

As a result of the same analysis, the conversion of 1,1,1,2-tetrafluoro-3,3-dichloropropene was 99.
%, The selectivity of 1,1,1,2,3,3-hexafluoro-3-chloropropane (HCFC-226ea) is almost
It was over 99%.

Example 10 60 g of SbCl ₅ was charged into a SUS316 autoclave with an inner volume of 500 ml and a PTFE inner tube. After cooling the autoclave to −30 ° C., 250 g of anhydrous HF was charged, the temperature was returned to room temperature, and then the temperature was heated to 80 ° C. with stirring. At this time,
While removing the generated HCl outside the system, the reaction pressure
It was kept at 12 kg / cm ² .

After the generation of hydrochloric acid ceased, the 1,1,1,2-tetrafluoro-3,3-obtained in Example 1 above was heated at 80 ° C.
Dichloropropene was charged at 100 g / Hr. At this time, the reaction pressure was kept at 12 kg / cm ² while removing generated HCl outside the system. After 3 hours, the charging of 1,1,1,2-tetrafluoro-3,3-dichloropropene was stopped, and the reaction was continued at 80 ° C. for 3 hours.

The reaction product was collected in a trap cooled to -70 ° C while removing HF with a water washing tower and an alkaline water tower. The collected organic matter was analyzed by gas chromatography.

As a result of the analysis, the conversion of 1,1,1,2-tetrafluoro-3,3-dichloropropene was 99%, and 1,1,1,2,3,3-hexafluoro-3- Chloropropane (HCFC-226ea) selectivity is 95%
Met. The main by-product was 1,1,1,2,3-trifluoro-3,3-dichloropropane.

200 g of anhydrous HF was placed in the reaction vessel in which the catalyst remained.
Was charged, and similarly, 300 g of 1,1,1,2-tetrafluoro-3,3-dichloropropene was charged and the reaction was carried out. As a result of analyzing the product by gas chromatography, the conversion of 1,1,1,2-tetrafluoro-3,3-dichloropropene was 99%, and 1,1,1,2,
3,3-hexafluoro-3-chloropropane (HCF
The selectivity of C-226ea) was 96%.

Example 11 In Example 8, the raw material was changed to 1,1,2-trifluoro-1,3,3-trichloropropene obtained in Example 3 above, and the same reaction was carried out. -Trifluoro-
The conversion of 1,3,3-trichloropropene is 99%,
The selectivity of 1,1,2,3,3-hexafluoro-3-chloropropane (HCFC-226ea) was 98%.

Example 12 In Example 8, the raw materials obtained in Example 2 above were 1,1,2,3-
As a result of carrying out the same reaction by changing to tetrafluoro-1,3-dichloropropene, the conversion of 1,1,2,3-tetrafluoro-1,3-dichloropropene is 99%, 1,
The selectivity of 1,1,2,3,3-hexafluoro-3-chloropropane (HCFC-226ea) was 97%.

(Hydrogen Reduction) Example 13 A reaction tube made of SUS316 having an inner diameter of 7 mm and a length of 150 mm was charged with 2.3 cc of a palladium catalyst supported on activated carbon at a concentration of 0.5% and charged with an electric furnace while flowing a nitrogen gas. After heating to ℃ and reaching a predetermined temperature, 1,1, obtained in Example 8 above
1,2,3,3-hexafluoro-3-chloropropane (HCFC-226ea) 5.5cc / min, hydrogen 14.5cc
It was introduced at the rate of / min. The reaction temperature was maintained at 150 ° C. The produced gas was washed with water and then analyzed by gas chromatography. The results are shown in Table 1 below.

Example 14 The same reactor as in Example 13 was charged with 2.3 cc of palladium catalyst supported on activated carbon at a concentration of 3%, heated to 200 ° C. in an electric furnace while flowing nitrogen gas, and heated to a predetermined temperature. After reaching 1,1,1,2,3,3-hexafluoro-3-chloropropane obtained in Example 8 above (HCFC-226e
A) was introduced at a rate of 5.5 cc / min, and hydrogen was introduced at a rate of 14.5 cc / min. The reaction temperature was 200 ° C. The generated gas is washed with water,
Analysis was carried out by gas chromatography. The results are shown in Table 1 below.

[0077] * 1,1,1,2,3,3-hexafluoropropane

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location B01J 23/44 X 23/70 X 23/745 23/86 X 27/10 X 27/12 X 37 / 08 C07C 17/087 17/23 17/25 19/10 21/18 9546-4H // B01J 21/18 X 32/00 C07B 61/00 300 (72) Inventor Noriaki Shibata Nishiichitsuya, Settsu-shi, Osaka 1 1 Daikin Industries, Ltd. Yodogawa Works (72) Inventor Tatsuo Nakata 1-1 Nishiichitsuya, Settsu-shi, Osaka Daikin Industries Ltd. Yodogawa Works

Claims (13)

[Claims] 1. A propane compound represented by the general formula (1): XCF ₂ CF ₂ CHClY (wherein X and Y are each a fluorine atom or a chlorine atom) is dehydrofluorinated, General formula (2): XCF ₂ CF = CClY (wherein, in this general formula, X and Y are the same as those described above).
And the fluorination of this propene compound in the liquid phase with hydrofluoric anhydride in the presence of an antimony catalyst to give 1,1,1,2,
The second step of obtaining 3,3-hexafluoro-3-chloropropane, and hydrogen reduction of this 1,1,1,2,3,3-hexafluoro-3-chloropropane in the presence of a noble metal catalyst,
A method for producing 1,1,1,2,3,3-hexafluoropropane, which comprises a third step of obtaining 1,1,2,3,3-hexafluoropropane. 2. The production method according to claim 1, wherein the hydrofluoric acid removal in the first step is performed with an alkaline aqueous solution. 3. The production method according to claim 2, wherein dehydrofluoric acid is carried out in an aqueous alkaline solution in the presence of a phase transfer catalyst. 4. The production method according to claim ₂ , wherein the alkaline aqueous solution is an aqueous solution of KOH, NaOH or Ca (OH) ₂ . 5. The production method according to claim 4, wherein dehydrofluoric acid is used in a slurry formed of calcium hydroxide and water. 6. The production method according to claim 1, wherein the dehydrofluoric acid in the first step is carried out by a gas phase reaction using at least one of chromium, iron and copper as a catalyst. 7. The production method according to claim 1, wherein dehydrofluoric acid in the first step is carried out by a gas phase reaction using an activated carbon catalyst. 8. The production method according to claim 1, wherein the antimony catalyst for the fluorination reaction in the second step is pentavalent antimony halide, trivalent antimony halide or a mixture thereof. 9. The method according to claim 8, wherein the antimony catalyst is a mixture of antimony pentafluoride and antimony trifluoride. 10. The production method according to claim 8, wherein the antimony catalyst is antimony pentafluoride. 11. The production method according to claim 1, wherein the fluorination reaction in the second step is carried out using anhydrous hydrofluoric acid as a solvent. 12. The production method according to claim 1, wherein the hydrogen reduction in the third step is performed in the presence of a noble metal catalyst composed of at least one of palladium, platinum and rhodium. 13. The compound represented by the general formula (1) is 1,
1,1,2,2,3-hexafluoro-3-chloropropane, 1,1,1,2,2-pentafluoro-3,3-
The dichloropropane, 1,1,2,2,3-pentafluoro-1,3-dichloropropane or 1,1,2,2-tetrafluoro-1,3,3-trichloropropane, according to claim 1. Manufacturing method.