Preparation method of potassium hexafluorophosphate

Abstract

The invention relates to the field of synthesis of an inorganic compound, and particularly relates to a preparation method of potassium hexafluorophosphate. The preparation method of the potassium hexafluorophosphate comprises the following steps: performing an initial reaction under a certain condition by taking potassium bifluoride (or potassium chloride), anhydrous hydrogen fluoride and phosphorus oxychloride as reaction raw materials to obtain a potassium hexafluorophosphate crude product, adjusting the acidity by using potassium hydroxide, eliminating iron ions, adsorbing and decoloring by activated carbon, performing evaporation and concentration on the crude product after removing impurities, and performing recrystallization to obtain the potassium hexafluorophosphate finished product. Compared with the traditional preparation method, the preparation method of the potassium hexafluorophosphate has the following advantages: the preparation method is simple in operation, mild in reaction and easy to control, and the use of a large amount of unstable, corrosive and toxic raw materials is avoided, so that the operation dangerousness is reduced; by adopting the potassium hexafluorophosphate produced by the method, the yield is up to 88 percent and the purity exceeds 99 percent.

Description

technical field [0001] The invention relates to the field of synthesis of inorganic compounds, in particular to a preparation method of potassium hexafluorophosphate. Background technique [0002] Hexafluorophosphate series is a very important class of inorganic fluorine salts, among which potassium hexafluorophosphate is an important one among hexafluorophosphates. Potassium hexafluorophosphate can be used to prepare other hexafluorophosphates, and can also be used as an organic fluorine substitution agent, such as a photopolymerization catalyst. The preparation method of hexafluorophosphate has been greatly developed due to the application of lithium hexafluorophosphate. In the late 20th century, chemists in some western countries such as the United States and Germany proposed the idea of ​​preparing lithium hexafluorophosphate from potassium hexafluorophosphate, which made the production of potassium hexafluorophosphate The workmanship has been greatly improved. [0003...

AI Technical Summary

Problems solved by technology

[0009] When potassium chloride, anhydrous hydrogen fluoride, and phosphorus pentachloride are used to prepare potassium hexafluorophosphate, the phosphorus pentachloride solid needs to be added in small amounts to the mixture of potassium chloride and anhydrous hydrogen fluoride several times. Overwhelming the difficulty of control, it is easy to cause danger