Method for preparing high-purity anhydrous aluminum chloride

Abstract

The invention relates to a method for preparing high-purity anhydrous aluminum chloride. The method is characterized by comprising the preparing process that analytically pure aluminum fluoride trihydrate and ammonium bifluoride are used as raw materials, and the steps of the preparing process include that firstly, AlF3H2O and NH4HF2 are evenly mixed in the proportion of 70:30, are loaded into a compact sintered alundum crucible and are put into a dry boiler; secondly, the temperature in the dry boiler is raised to be 150 DEG C to 180 DEG C, and the heating time is 2-3 h; thirdly, the temperature in the dry boiler is raised to be 250 DEG C to 280 DEG C, and the heating time is 2-3 h; fourthly, the temperature in the dry boiler is raised to be 500 DEG C to 550 DEG C, and the heating time is 3-4 h. The method for preparing the high-quality anhydrous aluminum chloride has the advantages that the quality stability is good, the color of the appearance is pure, cost is low, flying losses are few, the purity of products is high, and the requirement of fundamental experiment study can be met.

Description

technical field [0001] The invention relates to a preparation method of high-purity anhydrous aluminum fluoride. Background technique [0002] Aluminum fluoride is mainly used in industry to adjust the molecular ratio of the aluminum industry electrolyte to reduce the electrolysis temperature and improve the current efficiency. In the laboratory, anhydrous aluminum fluoride is often used to study the physical and chemical properties, phase balance, and electrochemical reaction of the electrolyte. etc., while the commercially available reagent aluminum fluoride is generally prepared by wet process, containing crystal water. Generally, vacuum distillation is widely used to prepare anhydrous aluminum fluoride, but complex equipment and high temperature of 1200°C are required. [0003] Aluminum fluoride is used industrially in the aluminum electrolysis industry to adjust the molecular ratio of the electrolyte. The alumina content in industrial aluminum fluoride is as high as 4...

AI Technical Summary

Problems solved by technology

However, in laboratory research, aluminum fluoride with high purity (purity greater than 99.5%) is required for basic research on the physical, chemical and electrochemical properties of electrolytes. Industrial aluminum fluoride can no longer meet the requirements.

However, among commercially available reagents, the purity of analytically pure anhydrous aluminum fluoride is only 85%-96%, which cannot meet the requirements of basic experimental research.