Method for preparing fluorine hydride addition reaction catalyst and fluorine-containing alkane

Abstract

The invention relates to a hydrogen fluoride addition reaction catalyst, which comprises a tertiary amine compound, fluoride of alkali metals or alkaline-earth metals, a crown ether compound and anhydrous hydrogen fluoride. The invention also provides a method for preparing fluorine-containing alkane, which comprises: firstly, performing stirring reaction on the tertiary amine compound and the anhydrous hydrogen fluoride according to the designed quantitative proportion to prepare a binary system catalyst; secondly, adding the alkali metal fluoride or the alkaline-earth metal fluoride and the crown ether compound to prepare a quaternary catalytic system catalyst; and thirdly, adding fluoroolefin to perform addition reaction and prepare a target product, namely the saturated fluorine-containing alkane. The catalyst liberates fluorine ions, better attacks the fluoroolefin to generate the target product, and strengthens the activity; and the conversion rate of raw materials and the selectivity of the products are higher. Moreover, due to addition of a cyclic ether or halogenated olefin solvent, the dissolubility of the raw materials and the products is increased, consequently contributing to the reaction system. Therefore, the reaction temperature and the reaction pressure of the technology are lower; the reaction time is shortened and the reaction efficiency is improved; the reaction system is basically neutral and noncorrosive; the equipment design is simpler; and the hydrogen fluoride addition reaction catalyst is easier to realize industrial mass production.

Description

technical field [0001] The invention belongs to the technical field of synthesizing saturated fluorine-containing alkanes by hydrogenation and fluorination of fluoroolefins, and specifically relates to a four-way catalyst for producing saturated fluorine-containing alkanes and a method for synthesizing saturated fluorine-containing alkanes using the four-way catalyst. Background technique [0002] The electronegativity of fluorine is relatively large, and the atomic radius is small, only slightly larger than the van der Waals radius of hydrogen atoms. Therefore, most of the hydrogen atoms in organic compounds can be replaced by fluorine atoms to form a large number of organic fluorine compounds. For example, the addition of hydrogen fluoride to unsaturated hydrocarbons can introduce fluorine into organic compounds. The introduction of fluorine into organic compounds is often accompanied by significant changes in physical and chemical properties, so organic fluorides have bee...

AI Technical Summary

Problems solved by technology

Its outstanding advantages are: low reaction temperature (less than 100°C), no production of octafluoroisobutene, high conversion rate of raw materials and product selectivity, long catalyst life, weakly alkaline reaction system and therefore basically non-corrosive, low equipment requirements, but There are still problems such as long reaction time and high reaction pressure, and it is difficult to realize continuous industrial production

[0005] Another example is the addition reaction of chlorotrifluoroethylene and hydrogen fluoride to prepare 1,1,1,2-tetrafluorochloroethane: U.S. Patent No. 3,755,477 uses chromium salt as a catalyst, and the reaction temperature is 320°C. Chlorotrifluoroethylene reacts with excess hydrogen fluoride , the addition product 1,1,1,2-tetrafluorochloroethane only has 13%, tetrafluoroethylene contains 20% instead in the reaction product, this reaction is not only poor to target product selectivity, and raw material conversion rate is low