JPH107605A - Production of 1,3,3,3-tetrafluoropropene - Google Patents

Abstract

PROBLEM TO BE SOLVED: To industrially produce 1,3,3,3-tetrafluoropropane useful as an intermediate raw material for medicines, agrochemicals and functional materials, a refrigerant, etc., from readily available raw materials on an industrial scale by fluorinating a specific compound with hydrogen fluoride in the vapor phase in the presence of a fluorinating catalyst. SOLUTION: (B) 1,1,1,3,3-Pentachloropropane is reacted with (C) hydrogen fluoride in the vapor phase in the presence of (A) a fluorinating catalyst [e.g. active carbon supporting an oxide, an (oxy)fluoride, an (oxy)chloride or an (oxy)fluorochloride of a metal which is Cr, Ti, Al, Mn, Ni or Co] to produce 1,3,3,3-tetrafluoropropene. Furthermore, the reaction is preferably carried out by using the component C in a molar amount of 4-30 times based on the component B at 200-600 deg.C temperature under 1-10kg/cm<2> pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to 1,3,3,3-
The present invention relates to a method for producing tetrafluoropropene.

[0002]

2. Description of the Related Art As a method for producing 1,3,3,3-tetrafluoropropene, conventionally, 1,3,3,3-tetrafluoro-1-propane iodide is dehydroiodated with alcoholic potassium hydroxide. Method (RN Hasze)
ldine et al. Chem. Soc. 1953, 11
99-4206; CA 48 5787f) or a method of dehydrofluorinating 1,1,1,3,3-pentafluoropropane with potassium hydroxide in dibutyl ether (IL Kunyanants et al., Izvest.
Akad. Nauk S.D. S. S. R. , Otdel.
Khim. Nauk. 1960, 1412-18; CA
55, 349f) and the like are known.

[0003]

The above-mentioned method of dehydrohalogenating with potassium hydroxide is excellent in the reaction rate and selectivity, but requires a stoichiometric amount of potassium hydroxide. And the raw materials 1,3
3,3-Tetrafluoro-1-propane iodide or 1,1,1,3,3-pentafluoropropane must be prepared in advance, and there are many difficulties for industrial application.

[0004]

SUMMARY OF THE INVENTION The present inventors have made 1,3,3 a starting material which can be obtained on an industrial scale or which can be relatively easily produced from raw materials available on an industrial scale. A study was conducted on the method for producing 1,3,3-tetrafluoropropene. -Tetrafluoropropene was obtained, and it was also found that it is particularly preferable to use activated carbon or activated carbon carrying a metal compound such as a chromium compound as a catalyst in the gas phase fluorination, and the present invention has been achieved. .

That is, the present invention is characterized in that 1,1,1,3,3-pentachloropropane is reacted with hydrogen fluoride in a gas phase in the presence of a fluorination catalyst.
A method for producing 3,3,3-tetrafluoropropene,
Further, the method for producing 1,3,3,3-tetrafluoropropene is characterized in that the fluorination catalyst is activated carbon or activated carbon supporting a metal compound such as a chromium compound.

The 1,1,1,3,3-pentachloropropane used in the present invention is prepared by reacting vinylidene chloride with chloroform in the presence of a copper amine catalyst (M. Kot).
ora et al., React. Kinet. Catal. Le
tt. , 1991, 44, 2, 415), a method of reacting carbon tetrachloride and vinyl chloride in the presence of a copper amine catalyst (M. Kotora et al., J. Mol. Catal., 1).
992, 77, 51), a method of reacting carbon tetrachloride and vinyl chloride in the presence of a ferrous chloride catalyst (J. Org. Ch.).
em. , USSR, 1969, 3, 2101).

[0007] The activated carbon according to the present invention is a plant based on wood, sawdust, charcoal, coconut husk charcoal, palm kernel charcoal, ash, etc., or a raw material from peat, lignite, lignite, bitumen, anthracite, etc. And petroleum based on petroleum residue, sulfuric acid sludge, oil carbon, etc. Since various types of such activated carbons are commercially available, they may be selected and used. For example, activated carbon produced from bituminous coal (for example, Calgon granular activated carbon CAL (Toyo Calgon Co., Ltd.)
And coconut shell charcoal (for example, manufactured by Takeda Pharmaceutical Co., Ltd.) and the like, but are not limited to these types and manufacturers. These activated carbons are usually used in the form of granules, but their shapes and sizes are not particularly limited.
The size of the reactor can be determined based on ordinary knowledge.

[0008] The activated carbon according to the present invention may be an oxide of one or more metals selected from aluminum, chromium, manganese, nickel, cobalt and titanium;
Activated carbon carrying fluoride, chloride, fluoride chloride, oxyfluoride, oxychloride, oxyfluoride chloride or the like may be used.

The method for preparing these metal-supported activated carbon catalysts is not limited, but chromium, titanium, manganese may be added to activated carbon as it is or to activated carbon previously modified with halogen such as hydrogen fluoride, hydrogen chloride, or chlorinated fluorinated hydrocarbon. One or two selected from nickel, nickel and cobalt
It is prepared by impregnating or spraying a solution of a soluble compound of one or more metals.

The amount of the metal carried is 0.1 to 80% by weight, preferably 1 to 40% by weight. Examples of the soluble compound of the metal supported on the activated carbon include nitrates, chlorides and oxides of the metal dissolved in a solvent such as water, ethanol and acetone. Specifically, chromium nitrate, chromium trichloride, chromium trioxide, potassium dichromate, titanium trichloride, manganese nitrate, manganese chloride, manganese dioxide, nickel nitrate, nickel chloride, cobalt nitrate, cobalt chloride, etc. may be used. it can.

[0011] The catalyst supporting the metal by any method is treated with a fluorinating agent such as hydrogen fluoride, fluorinated (and chlorinated) hydrocarbon at a temperature higher than a predetermined reaction temperature before use, and It is effective to prevent a change in the composition of the catalyst inside. Supplying oxygen, chlorine, fluorinated or chlorinated hydrocarbons, etc. into the reactor during the reaction is effective for extending the life of the catalyst, improving the reaction rate, and improving the reaction yield.

The reaction temperature is 200-600 ° C., preferably 300-500 ° C. If the reaction temperature is lower than 200 ° C., the reaction is slow and not practical. When the reaction temperature exceeds 600 ° C., the catalyst life is shortened, and the reaction proceeds quickly, but decomposition products and the like are generated, and the selectivity of 1,3,3,3-tetrafluoropropene decreases, which is not preferable. .

In the method of the present invention, the molar ratio of 1,1,1,3,3-pentachloropropane / hydrogen fluoride supplied to the reaction zone can vary depending on the reaction temperature.
It is 1/30, preferably 1/4 to 1/10. Hydrogen fluoride is 1,1,1,3,3-pentachloropropane 3
Exceeding 0 mole times causes a reduction in the amount of organic matter to be treated in the same reactor and separation of a mixture of unreacted hydrogen fluoride and product discharged from the reaction system, while hydrogen fluoride is more than 4 mole times. When the amount is too small, the reaction rate is decreased, and the selectivity is undesirably decreased.

In the method of the present invention, it is preferable to use an excess amount of hydrogen fluoride, so that unreacted hydrogen fluoride is separated from unreacted organic substances and products and recycled to the reaction system. Separation of hydrogen fluoride and organic matter can be performed by a known means.

The reaction pressure is not particularly limited, but is preferably ¹ to 10 kg / cm ² from the viewpoint of the apparatus. It is desirable to select conditions so that the raw material organic substances, intermediate substances and hydrogen fluoride present in the system are not liquefied in the reaction system.
The contact time is usually 0.1 to 300 seconds, preferably 5 to 6 seconds.
0 seconds.

The reactor may be made of a material having heat resistance and corrosion resistance to hydrogen fluoride, hydrogen chloride and the like, and is preferably made of stainless steel, Hastelloy, Monel, platinum or the like.
It can also be made of materials lined with these metals.

The product containing 1,3,3,3-tetrafluoropropene which is treated by the method of the present invention and flows out of the reactor is purified by a known method to obtain a product. Although the purification method is not limited, for example, a product from which hydrogen fluoride to be recovered is separated in advance is first washed with water or / and an alkaline solution to remove acidic substances such as hydrogen chloride and hydrogen fluoride, and then dried. Thereafter, distillation can be performed to remove organic impurities.

[0018]

【Example】

[Preparation Example 1] 100 g of crushed coconut shell charcoal made by Toyo Calgon (P
CB (4 × 10 mesh) was immersed in 150 g of pure water, and separately mixed with a solution prepared by dissolving 40 g of a special-grade reagent CrCl ₃ .6H ₂ O in 100 g of pure water, stirred, and allowed to stand overnight. Next, the activated carbon was removed by filtration, and then 200
C. and baked for 2 hours. The obtained chromium-supporting activated carbon was converted into a cylindrical SU having a diameter of 5 cm and a length of 30 cm equipped with an electric furnace.
S316L into a reaction tube,
The temperature was raised to 00 ° C., and at the time when the outflow of water was no longer observed, the concentration of nitrogen gas was gradually increased by accompanying hydrogen fluoride. When a hot spot due to the adsorption of hydrogen fluoride on the filled chromium-supported activated carbon reached the outlet end of the reaction tube, the reactor temperature was raised to 400 ° C., and this state was maintained for 2 hours to prepare a catalyst.

[Preparation Example 2] 100 g of crushed coconut shell made of Toyo Calgon (PCB 4 × 10 mesh) and 150 g of pure water
, And separately mixed and stirred with 200 g of a 20% aqueous solution of TiCl _3, and left overnight. Next, the activated carbon was removed by filtration and calcined at 200 ° C. for 2 hours in an electric furnace. The obtained titanium-supported activated carbon was charged into a cylindrical SUS316L reaction tube having a diameter of 5 cm and a length of 30 cm equipped with an electric furnace,
The temperature was raised to 200 ° C. while flowing nitrogen gas, and when the outflow of water was no longer observed, the concentration of nitrogen gas was gradually increased by accompanying hydrogen fluoride. When a hot spot due to the adsorption of hydrogen fluoride on the filled titanium-supported activated carbon reached the outlet end of the reaction tube, the reactor temperature was raised to 400 ° C., and the state was maintained for 2 hours to prepare a catalyst.

[Preparation Example 3] 336 g of special grade reagent CrCl
The ₃ · 6H ₂ O was 1L dissolved in pure water. To this solution was added granular γ-alumina 250 having a diameter of 5 mm and a surface area of 340 m ^2.
ml was immersed and left overnight. Next, γ-alumina was removed by filtration, kept at 100 ° C. in a hot air circulating dryer, and further dried overnight. The obtained chromium-carrying alumina was cylindrical S with a diameter of 5 cm and a length of 30 cm equipped with an electric furnace.
The reactor was filled in a US316L reaction tube, heated to 300 ° C. while flowing nitrogen gas, and when the outflow of water was no longer observed, hydrogen gas was accompanied by hydrogen fluoride to gradually increase the concentration. When a hot spot due to fluorination of the charged chromium-supported alumina reached the outlet end of the reaction tube, the reactor temperature was raised to 450 ° C., and the state was maintained for 1 hour to prepare a catalyst.

Example 1 Preparation Example 1 as a gas phase fluorination catalyst in a gas phase reactor (SUS316L, 1 inch in diameter and 30 cm in length) comprising a cylindrical reaction tube equipped with an electric furnace.
150 ml of the catalyst prepared in the above was charged. About 100ml /
While flowing nitrogen gas at a flow rate of 200 min.
° C and hydrogen fluoride was entrained with nitrogen gas at a rate of about 0.10 g / min. The temperature of the reaction tube was raised to 500 ° C. and kept for 1 hour. Next, the temperature of the reaction tube was lowered to 400 ° C., and the supply rate of hydrogen fluoride was set at 0.10 g / min.
1,1,1,3,3-Pentachloropropane was vaporized in advance, and supply to the reactor was started at a rate of 0.32 g / min.

Since the reaction was stable 1 hour after the start of the reaction, the product gas flowing out of the reactor was blown into water for 2 hours from that time to remove acidic gas, and then 21.2 g of dry ice-acetone trap was used. Organics were collected. The results of analyzing the collected organic matter by gas chromatography are shown in Table 1.

[0023]

[Table 1]

Example 2 Using the catalyst prepared in Preparation Example 2, after the same preparation step as in Example 1, the same reaction operation, recovery operation, and analysis as in Example 1 were performed under the conditions shown in Table 1. Was.
Table 1 shows the results.

[Examples 3 and 4] Using activated carbon alone, under the conditions shown in Table 1, the same reaction operation, recovery operation,
Analysis was carried out. Table 1 shows the results.

REFERENCE EXAMPLE After the same preparation steps as in Example 1 except that the chromium-supported alumina catalyst of Preparation Example 3 was used as the catalyst, the same reaction operation as in Example 1 was performed under the conditions shown in Table 1.
Recovery operation and analysis were performed. Table 1 shows the results.

[0027]

According to the process for producing 1,3,3,3-tetrafluoropropene of the present invention, 1,1,1,3,3-pentachloropropane is used as a raw material and 1,1,3,3-tetrachloropropane is continuously produced. Since tetrafluoropropene can be produced, it is useful as an industrial production method.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location B01J 27/10 B01J 27/125 X 27/12 27/128 X 27/125 27/132 X 27 / 128 27/135 X 27/132 7106-4H C07C 17/20 27/135 7106-4H 17/25 C07C 17/20 C07B 61/00 300 17/25 B01J 23/74 311X // C07B 61/00 300 321X

Claims (3)

[Claims] 1. The method according to claim 1, wherein 1, 1
A process for producing 1,3,3,3-tetrafluoropropene, comprising reacting 1,1,3,3-pentachloropropane with hydrogen fluoride. 2. The method for producing 1,3,3,3-tetrafluoropropene according to claim 1, wherein the fluorination catalyst is activated carbon. 3. An oxide, fluoride, chloride, fluorinated chloride, oxyfluoride of one or more metals selected from chromium, titanium, aluminum, manganese, nickel and cobalt as the fluorination catalyst. 2. The method for producing 1,3,3,3-tetrafluoropropene according to claim 1, wherein the activated carbon is an activated carbon carrying oxychloride or oxyfluoride chloride.