Method for cracking hexafluoropropylene dipolymer to prepare perfluoro amyl ether and perfluoro amyl ether

Abstract

The invention belongs to the field of fluorine chemical industry and specifically relates to a method for cracking hexafluoropropylene dipolymer to prepare perfluoro amyl ether and perfluoro amyl ether. The preparation method comprises the steps: 1) perfluoro pentacarbonyl ketone preparation: 1.1) sending the hexafluoropropylene dipolymer into an oxidizing furnace to perform cracking reaction withoxygen under the first catalyst condition; separating a cracked product to obtain perfluoro acetylfluoride; 1.2) preparing the perfluoro pentacarbonyl ketone under the second catalyst action with hexafluoropropylene and the perfluoro acetylfluoride prepared in the step 1.1) as raw materials; 2) selectively adding tertiary amine or a phase transfer catalyst into an inert dipole non-proton organiccompound solution to react under the alkali metal fluoride action with the pentacarbonyl ketone obtained in the step 1) and an alkylation reagent as the raw materials, so as to prepare the perfluoro amyl ether. According to the method disclosed by the invention, hexafluoropropylene tripolymer is utilized as a raw material to generate the perfluoro pentacarbonyl ketone, and then the perfluoro pentacarbonyl ketone reacts with the alkylation reagent to generate the perfluoro amyl ether; thus, the conversion efficiency is high, conditions are moderate, and the whole technological process is simpleto operate.

Description

technical field [0001] The invention belongs to the field of fluorine chemical industry, and in particular relates to a method for preparing perfluoroamyl ether by cracking hexafluoropropylene dimer and perfluoroamyl ether. Background technique [0002] Hydrofluoroethers (HFEs) are a class of commercially valuable compounds. Hydrofluoroethers have found use as replacements for chlorofluorocarbons (CFCs) in numerous applications. Unlike chlorofluorocarbons, hydrofluoroethers containing fluorine as the only halogen basically do not affect the Earth's ozone layer. The Ozone Depletion Potential (ODP) exhibited by such hydrofluoroethers (HFEs) is therefore considered to be zero. In addition, this hydrofluoroether is more easily degraded in the earth's atmosphere, and its low global warming potential (GWP) and short atmospheric residence time make it an ideal replacement for chlorofluorocarbons (CFCs). [0003] Hydrofluoroethers generally refer to those ethers in which hydrogen...

AI Technical Summary

Problems solved by technology

Methods (2) and (3) are rarely used in actual production due to the high cost of the preparation process and low product yield

Most reports are method (4) using the addition reaction of fluorine-containing alcohols and fluorine-containing olefins to prepare hydrofluoroethers. The produced hydrofluoroethers are either flammable or have a pungent odor, which does not meet the needs of the electronics and other industries. ; and in the process of preparing hydrofluoroethers by the reaction of fluorine-containing alcohols and fluorinated olefins, there will be the production of double bond by-products close to the boiling point of the target product, so the purification process of the final product is increased, and all chlorine or bromine in the purification process High toxicity, strict operation requirements

In method (5), the method of electrofluorination chemistry is usually used to prepare fluorinated acid fluorides, and further to prepare hydrofluoroethers. However, the electrofluorination chemistry method not only consumes a lot of electricity, has low yield and many by-products in the production process, but also The process requires a large amount of anhydrous hydrogen fluoride; and electrofluorine chemistry usually produces a large number of isomers rather than a specific perfluorinated acid fluoride, which are almost impossible to use due to the same or similar boiling points. Separation and purification by rectification technology, the resulting hydrofluoroether product is also a mixture, which cannot be separated by rectification technology

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