Internal circulation reactor and method for continuously preparing phosphorus pentafluoride

Abstract

The invention discloses an internal circulation reactor and method for continuously preparing phosphorus pentafluoride. The internal circulation reactor comprises a cylinder body with a heat exchange jacket, wherein planar end closures are arranged at the upper and lower ends of the cylinder body, and a concentric inner cylinder body is arranged in the cylinder body; the upper end closure is provided with a mixed gas leading-out pipe; the lower end closure is provided with a three-way gas intake pipe; and a reaction solution eduction pipe and a feed liquid ingress pipe are arranged on the cylinder body. The process of preparing phosphorus pentafluoride comprises the following steps: blowing the reactor with an inert gas; creating a low temperature environment of the reactor with a refrigerant; adding a phosphorous pentachloride solution, anhydrous hydrogen fluoride and the inert gas to the reactor for reaction; and continuously leading out mixed gas containing phosphorus pentafluoride and part of a low-concentration phosphorous pentachloride solution, and at the same time continuously adding a phosphorous pentachloride concentrated solution, anhydrous hydrogen fluoride and the inert gas to realize continuous operation. The internal circulation reactor and method for continuously preparing phosphorus pentafluoride have the advantages that the concentration stability of reactants in the reactor can be maintained, and continuous production and automatic control of phosphorus pentafluoride are realized.

Description

technical field [0001] The invention relates to an internal circulation reactor and method for continuously preparing phosphorus pentafluoride, belonging to the technical field of preparation of phosphorus-containing fluorides. Background technique [0002] In recent years, the preparation methods of phosphorus pentafluoride announced by relevant patent documents are mainly as follows: phosphorus pentachloride reacts with anhydrous hydrogen fluoride to generate a mixed gas of phosphorus pentafluoride and hydrogen chloride, see CN101353161A, CN1339401A, CN1263047A, and 5-279003, JP 6-56413; direct gas-solid reaction of fluorine and phosphorus to prepare phosphorus pentafluoride, see CN1151960C; reaction of anhydrous hydrogen fluoride and concentrated phosphoric acid to prepare hexafluorophosphoric acid, and then dropwise add hair to hexafluorophosphoric acid Phosphorus pentafluoride gas produced by nicotinic acid, see CN101570326A; use calcium fluoride and phosphorus pentoxid...

AI Technical Summary

Problems solved by technology

The batch method makes it more difficult to control the chemical reaction process, which is not conducive to the automatic control of the production process. The output and concentration of phosphorus pentafluoride have large fluctuations, which will affect the quality stability of the final product lithium hexafluorophosphate

In addition, the batch method is not conducive to the continuous large-scale production of phosphorus pentafluoride. The batch method makes the production efficiency of a single device low, and it is difficult to increase the yield by increasing the flow rate of the reactant

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