Extraction of graphite by chlorination roasting method

The chlorination roasting method is to mix graphite and a certain reducing agent together, and roast it at high temperature under a specific equipment and atmosphere. The valuable metals in the material are transformed into gaseous or condensed phase metal chlorides, which are separated from the rest of the components to make the graphite Purification process.

Impurities in graphite can be decomposed into oxides with higher melting and boiling points, such as SiO2, Al2O3, Fe2O3, CaO, and MgO under high temperature conditions. These oxides will react with chlorine gas at a certain high temperature and atmosphere, and the metal oxides and chlorine gas will react to form chlorides with a lower boiling point. Therefore, at a lower temperature, these chlorides can be vaporized and escaped to achieve separation from the graphite, so that the graphite can be purified.

The advantages of the chlorination roasting method are energy saving, high purification efficiency (>98%), and high recovery rate. However, there are also problems such as poisonous chlorine, severe corrosiveness and serious environmental pollution. The purity of the graphite produced in the process is limited, and the process stability is not good, which affects the application of the chlorination method in actual production, and it needs to be further improved and improved.