Continuous producing device and method of phosphorus pentafluoride

Abstract

The invention provides a continuous producing device of phosphorus pentafluoride, comprising a phosphorus single-substance closing silo, a spiral conveyer, a fluorine-phosphorus reactor, a cooling pipeline and a multi-grade filter. The continuous producing device of phosphorus pentafluoride is characterized in that the upper end of the spiral conveyer is connected to the lower end of the phosphorus single-substance closing silo, the tail end of the spiral conveyer is connected to the upper part of the fluorine-phosphorus reactor; one end of the fluorine-phosphorus reactor is connected with the cooling pipeline, and the other end of the cooling pipeline is connected with the multi-grade filter. The invention further provides a method for continuously producing phosphorus pentafluoride by using the device; the high-purity phosphorus pentafluoride gas is obtained by pre-reaction, continuous reaction, cooling and multi-grade filtering. According to the continuous producing device, the continuous production of phosphorus pentafluoride is realized; the continuous producing device has the advantages of being high in production efficiency, simple, safe and reliable in operation and good in product quality; the product purity can reach 99.8% above; therefore, the continuous producing device can be directly applied to the production of the lithium hexafluorophosphate.

Description

technical field [0001] The invention relates to a device and a process for producing inorganic fluorides, in particular to a device and a process for continuously producing phosphorus pentafluoride. Background technique [0002] Phosphorus pentafluoride is an important inorganic fluoride, which can be used in the electronics industry, polymer materials and organic synthesis catalysts. In recent years, high-performance lithium batteries have increasingly become a development trend. As an important raw material for the production of lithium hexafluorophosphate materials for lithium battery electrolytes, the demand and quality requirements are getting higher and higher. Therefore, large-scale continuous production of high-quality phosphorus pentafluoride is very important. significance. [0003] At present, there are two main processes for industrialized production of high-purity phosphorus pentafluoride: [0004] 1. Using PCl 5 React with HF to produce PF 5 [0005] PCl ...

AI Technical Summary

Problems solved by technology

[0008] However, the existing production processes all adopt intermittent production, and the production efficiency is low, which cannot meet the needs of large-scale production of high-purity phosphorus pentafluoride. It is: the preparation process of phosphorus pentachloride, this application discloses a kind of preparation process of phosphorus pentafluoride, the process steps are as follows: pre-add solid elemental phosphorus in the gas-solid reaction device, control the internal pressure of the gas-solid reaction device at Under the conditions of less than 0.5MPa and reaction temperature lower than 600°C, fluorine gas is introduced to generate crude phosphorus pentafluoride. The crude product is cooled to -35~-60°C through a precooler, and then introduced into a rectification tower to control The temperature of the reboiler in the rectification tower is between -35°C and -40°C, the temperature of the condenser in the rectification tower is controlled between -60 and -85°C, and the total reflux is maintained. After reaching equilibrium, the reflux ratio is controlled 10:1~1:1, the desired phosphorus pentafluoride product can be obtained by rectification and separation

Its disadvantage is that red phosphorus raw materials need to be added to the reactor in advance, and the operation is intermittent, which is cumbersome and labor-intensive.

Its shortcoming is that the raw material phosphorus pentachloride is extremely easy to be affected with moisture and deliquescence, and the product contains PCl 3 , POCl 3 and other impurities; and the method has complex process steps, harsh reaction conditions, and poor production continuity

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