JPS6045857B2 - Process for producing perfluoroisobutyric acid fluoride and/or perfluorodiisopropyl ketone - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process for producing perfluoroisoacetic acid fluoride and perfluorodiisopropyl ketone, and more particularly to perfluoroisoacetic acid fluoride and perfluorodiisopropyl ketone catalyzed by a mixture of nickel oxide and an alkali metal.

Concerning the manufacturing method of noodles. Perfluoroisoacetic acid fluoride is useful as a raw material for vinyl ethers when reacted with hexafluoropropylene epoxide, or as an intermediate for producing working fluids.

On the other hand, perfluorodiisopropyl ketone is useful as an organic solvent, a fluororubber vulcanizing agent, and a modifier for fluoropolymers. Conventionally, several methods have been proposed for producing perfluoroisoacetic acid fluoride and/or perfluorodiisopropyl ketone.

Many of these react with catalysts such as CsFNKF, KHF2, (C2H5) in solvents such as acetonitrile.
propylene fluoride and fluorophosgene (COF) at temperatures between 100 and 1500 C in the presence of NF, etc.

) [F., S., Fawce, C., W., Tullock and D.
Day, Coffman, The Journal of the American Chemical Society (J, Am, Chem, Soc,) Vol. 84, 4275.
Page (196 details) and R.D. Smith (R.D.
. Smith), F., S. Fawcett (F.S.
. Fowcett) and Day, Day, Coffman (D.
D. Coffman), The Journal of the American Chemical Society (J, Am, Che
m, Soc. ) No. 8, page 4285 (details 196)].
However, these methods require COF2 to be produced in other reaction systems, and KF. ．． CsF and the like are hygroscopic and difficult to handle, and the reaction has to be carried out in a purified solvent, resulting in very low efficiency.

The present inventors conducted research on a method for producing perfluoroisobutyric acid fluoride and perfluorodiisopropyl ketone by a gas phase oxidation reaction of hexafluoropropene (hereinafter referred to as HFP) without using a solvent. It has been found that when an alkali metal compound is used as a catalyst, both of the above-mentioned desired compounds can be produced from only T and oxygen in surprisingly high yields.

Based on this knowledge, the present inventors further conducted various studies and studies to complete the present invention. That is, the gist of the present invention resides in a process for producing perfluoroisobutyric acid fluoride and/or perfluorodiisopropyl ketone, which is characterized in that HFP and oxygen are reacted in the gas phase in the presence of a mixture of nickel oxide and an alkali metal compound. . According to the production method of the present invention, since it is a gas phase reaction, the catalyst is easy to handle, can be charged and taken out continuously, and the product can be easily separated by distillation alone.

Furthermore, since the raw materials are only HFP and oxygen, the cost is extremely low, making it an extremely preferred manufacturing method for industrial production. The catalysts used in the present invention are nickel oxide and alkali metal compounds. The nickel oxide may be any nickel oxide such as nickel monoxide and nickel sesquioxide that are commercially available as reagents.

The alkali metal compounds are preferably oxides and hydroxides of alkali metals such as potassium and cesium, but also salts such as sulfates, halides (chlorides, fluorides, sulfides and iodides), nitrates, etc. good.

It is thought that during the reaction, all or part of these compounds except for fluoride are converted into alkali fluoride by HFP and exhibit catalytic action together with nickel oxide. Preferred alkali metal compounds are potassium hydroxide, cesium hydroxide, potassium fluoride and cesium fluoride. The mixing ratio of nickel oxide and alkali metal compound is 0.001 to 1 part by weight of nickel oxide to 1 part by weight of nickel oxide.
It is appropriate to express it in parts by weight.

When using nickel oxide alone or an alkali metal compound alone, perfluoroisobutyric acid fluoride and perfluorodiisopropyl ketone are not produced, or even if they are produced, only a small amount is produced. From the viewpoint of the conversion rate of hexafluoropropene and the selectivity to the target product, the preferred mixing ratio is 0.05 to 0.0.1 parts by weight of the alkali metal compound to 1 part by weight of nickel oxide. This is the heel volume. The ratio of RHFP and oxygen is not particularly limited, but mainly when obtaining perfluoroisobutyric acid fluoride, 11F'PO. 3-1
When it is desired to obtain a larger amount of perfluorodiisopropyl ketone, it is preferable to use 1.5 to 5 moles of 8P per mole of oxygen. A suitable reaction temperature is 100 to 350°C.

At temperatures below 100°C the conversion is lower and at temperatures above 350°C the selectivity is lower.

Therefore, such temperatures are not suitable for industrial production. The preferred reaction temperature is 150-270°C. The reaction pressure is not particularly limited, but is preferably normal pressure to 5k91cItG.

The space velocity is influenced by other reaction conditions, especially the reaction temperature, but is usually 10 to 100,000 r, preferably 30 to 100,000 r.
It is 300hr1.

Next, Examples will be shown to further specifically explain the manufacturing method of the present invention.

Example 1 10 mL of ion-exchanged water was added to 10 y of nickel monoxide of special reagent grade and 0.59 y of sodium hydroxide of special reagent grade, and after stirring and mixing thoroughly, the mixture was dried at 100'C for 24 hours, and further heated at 400°C in an electric furnace. heated with.

After cooling, it is crushed and classified into 20 to 60 mesh, and the length is 0.
．． The catalyst 3.
5y and heated at 350° C. under nitrogen flow. The reactor was then cooled to 250 DEG C., HFP and oxygen in the proportions shown in Table 1 were passed through at a space velocity of 80 hr@-1, and the exhaust gas was analyzed by gas chromatography. The results are shown in Table 1. Example 2 The same procedure as in Example 1 was repeated except that nickel dioxide 10V was used instead of nickel monoxide and cesium fluoride 1q was used instead of potassium hydroxide, and the results shown in Table 1 were obtained.

Example 3 50 mL of ion-exchanged water was added to 100 f of nickel monoxide and 5 f of potassium hydroxide, and after stirring and mixing thoroughly, the clay-like mixture was extruded into a rod shape with a diameter of 5 wm, and heated at 100°C for 2 hours.
It was dry between servings.

Cut the dried rod into 1 cm length and form into pellets.
The mixture was heated in an electric furnace at 400° C. for 5 hours to obtain a catalyst. The obtained catalyst 40y was packed into a Pyrex glass reaction tube with a diameter of 1 inch and a length of 1 m, and after nitrogen was passed through it at 350°C for 3 hours, it was cooled to 250°C and the reaction was carried out under the conditions shown in Table 1. It started.

The results are also shown in Table 1. Example 4 50 mt of water was added to 100 y of nickel monoxide and 10 f of cesium fluoride, and catalyzed in the same manner as in Example 3.

Claims (1)

Claims: 1. A process for producing perfluoroisobutyric acid fluoride and/or perfluorodiisopropyl ketone, which comprises reacting hexafluoropropene and oxygen in the gas phase in the presence of a mixture of nickel oxide and an alkali metal compound. 2 The mixing ratio of nickel oxide and alkali metal compound is 1 part by weight of nickel oxide to 0.00 parts by weight of alkali metal compound.
001 to 1 part by weight. 3. The production method according to claim 1 or 2, wherein the alkali metal is potassium or cesium. 4 The proportion of hexafluoropropene and oxygen is 1
The method according to any one of claims 1 to 3, wherein the amount of hexafluoropropene is 0.3 to 5 moles per mole. 5. The manufacturing method according to any one of claims 1 to 4, wherein the reaction temperature is 100 to 350°C.