Battery-grade lithium carbonate lithium is first of all the purity of 99.5 or more, the other impurity content needs to meet the national standard. Also need to have stable physicochemical properties battery-grade lithium carbonate melting point of 723 ° C, boiling point of 1230 ° C, density of about 2.11g/cm³4 (also such as white crystalline powder, odorless and tasteless, high thermal and electrochemical stability) and other characteristics. There are many ways to generate battery grade, so which methods are commonly used? Let's find out today:
Causticization method, because it has the advantages of a relatively simple process and is suitable for large-scale production. This is a very commonly used method, which converts crude lithium carbonate into lithium bicarbonate by carbonization reaction, and then decomposes it by heating to get battery-grade lithium carbonate.
Steps: The process of generating battery-grade lithium carbonate by carbonization decomposition method mainly includes batching and pretreatment, carbonization reaction, filtration, removal of impurities, concentration and crystallization, drying and packaging, etc. The following is the detailed chemical equation of the process. The following is the detailed chemical equation of the process Carbonization reaction:
[ \text{Li}_2\text{CO}_3 + \text{CO}_2 + \text{H}_2\text{O} \rightarrow 2\text{LiHCO}_3 ]
In this step, crude lithium carbonate reacts with carbon dioxide and water to form lithium bicarbonate.
Thermal decomposition reactions (which may occur during the concentrated crystallization stage):
[ 2\text{LiHCO}_3 \rightarrow \text{Li}_2\text{CO}_3 + \text{H}_2\text{O} + \text{CO}_2 ]
Lithium bicarbonate decomposes under heating conditions, regenerating lithium carbonate and releasing water vapor and carbon dioxide.
Equipment to be used: stirring tank/mixer, reactor, carbonization tower, filtration equipment, washing tank, drying equipment, pulverizer and sifter, packaging equipment, and other auxiliary equipment such as transfer pumps, valves, pipelines, etc. are needed to ensure the smooth running of the production process.