As an important raw material for lithium batteries, the production process of battery-grade lithium carbonate is crucial. The principle of producing battery-grade lithium carbonate with lithium pyroxene as raw material is based on a series of chemical reactions and physical separation processes. The following are the specific principles and processes:
First, raw material preparation
First of all, lithium pyroxene needs to be selected and cleaned to remove the impurities. This step is the basis for subsequent processing, and the quality of lithium pyroxene directly affects the quality and yield of the final product.
Second, the decomposition of lithium pyroxene
Lithium pyroxene decomposition is a key link in the production process. Usually use acid dissolution or high temperature melting method, the lithium oxide in lithium pyroxene into soluble lithium salts. The acid dissolution method uses strong acids such as sulphuric acid, while the high-temperature smelting method needs to be carried out at high temperatures and in a specific reducing atmosphere.
Three, Extraction and purification
The decomposed solution or melt is filtered to remove the residue from it, and then lithium carbonate is extracted by precipitation and evaporation. In this step, further purification of lithium carbonate is required to remove the impurities and ensure that its purity meets the battery-grade standard.
Fourth, the crystallisation and drying of lithium carbonate
The purified lithium carbonate solution is crystallised under specific conditions to form lithium carbonate crystals. Then it is dried to remove water and other volatile impurities.
Five Packaging and Storage
Finally, the dried lithium carbonate is crushed and sieved to obtain battery-grade lithium carbonate that meets the requirements. Finally, strict quality inspection is carried out to ensure that the product quality is qualified, and then packaged and stored.