Device and method for preparing trifluoromethanesulfonyl fluoride

Abstract

The invention relates to a device and a method for preparing trifluoromethanesulfonyl fluoride, and belongs to the technical field of trifluoromethanesulfonyl fluoride preparation. The device comprises a trifluoromethanesulfonyl chloride storage tank, a reactor, a reflux heat exchanger and a trifluoromethanesulfonyl fluoride storage tank; the device is few in equipment, the technological process is simplified, the safety is high, trifluoromethanesulfonyl fluoride with high purity can be collected while reaction is conducted, the equipment utilization efficiency is greatly improved, and the cost is effectively reduced; according to the method, trifluoromethanesulfonyl chloride and potassium fluoride are used as raw materials, cyclohexanone is used as a solvent, and an unreacted excessive fluorinating agent and the solvent are convenient to recover; according to the method, trifluoromethanesulfonyl fluoride with the purity of 99.5 vol% or above can be collected through simple reflux after reaction at a high temperature, the product purity is high, hydrogen fluoride and other light component impurities are avoided, and the method is suitable for industrial production.

Description

technical field [0001] The invention relates to a device and method for preparing trifluoromethanesulfonyl fluoride, belonging to the technical field of trifluoromethanesulfonyl fluoride preparation. Background technique [0002] Trifluoromethanesulfonyl fluoride has a boiling point of -21.7°C under normal pressure. It is a gas that has a weak odor and is easily liquefied at normal temperature. It does not react with hydrogen, is insoluble in cold water, hydrogen fluoride, etc., and is easily hydrolyzed under hot water and alkaline conditions. Trifluoromethanesulfonyl fluoride is an important intermediate in the field of fine chemicals, and can be used as an important raw material for organic synthesis, pesticides and medicines, ionic liquids and lithium ion electrolytes. [0003] Trifluoromethanesulfonyl fluoride has photolysis method, chemical direct fluorination method, electrolysis method, and the method of fluorinating trifluoromethanesulfonyl chloride with potassium fl...

AI Technical Summary

Problems solved by technology

This method has the following problems: 1) easy hydrolysis produces trifluoromethanesulfonic acid and hydrogen chloride gas, which corrodes equipment and is dangerous to operate; 2) the product purity obtained is not high; 3) potassium fluoride and product potassium chloride are all soluble in water , as the reaction proceeds, potassium fluoride is generated to wrap potassium fluoride, so that the reaction rate is gradually slowed down, and the reaction efficiency is low; 4) excessive potassium fluoride and potassium chloride should not be separated, resulting in waste of raw materials

There are following problems in this method: 1) adopt two kinds of solvents, separation difficulty, bigger pollution; 2) reaction temperature is lower, reaction rate is low, and reaction time is longer; 3) product potassium chloride and potassium fluoride are not suitable for separation; 4) The purity of the obtained product is not high

The above two purification methods have the following problems: (1) There are many purification steps, and there are many equipments needed, and multi-step gas-liquid separation equipment and water removal equipment are needed; The route is long, and the hydrogen is removed in the last step, which is prone to hydrogen leakage and explosion accidents, so the tightness requirements for all purification equipment are relatively high; (3) trifluoromethanesulfonyl fluoride can be hydrolyzed in alkaline solution, use Carbonate solution absorbs and removes hydrogen fluoride, and absorbs part of trifluoromethanesulfonyl fluoride at the same time, resulting in product loss. At the same time, the reaction between trifluoromethanesulfonyl fluoride and carbonate produces carbon dioxide, which brings new impurities and affects the purity of the product. (4) take the method of introducing moisture first, and then remove water through the dehydrating agent, and the activation of the dehydrating agent needs to consume inert gas and electric energy, so that the energy consumption of purification is increased; (5) the product is finally obtained by simple gas-liquid separation to remove hydrogen , light component impurities such as carbon tetrafluoride (CF 4 ), sulfoxide difluoride (SOF 2 ), carbon dioxide (CO 2 ) and oxygen difluoride (OF 2 ) was not removed through effective measures, and the final purity of the product trifluoromethanesulfonyl fluoride was not mentioned

Patent CN201410631152.1 The No. 718 Research Institute of China Shipbuilding Corporation provides the purification of trifluoromethanesulfonyl fluoride gas generated by electrolysis in the rectification tower, and the final product has a high purity (99.5%), but the purification method It is more suitable for the situation of small production volume. For the situation of large production volume, more equipment is required and the efficiency is low.

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