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What is high purity graphite and its production?
Graphite with carbon mass fraction greater than 99%. 99% is called pure graphite. High purity graphite is mainly used for smelting high-purity metal or nonmetal materials, such as sintering molds, heating elements, crucibles, trays and fixtures. Spectral graphite, nuclear graphite and aerospace graphite also belong to the category of high purity graphite.

Compared with the production of ordinary graphite materials, the production process in high purity graphite has the following characteristics: (1) petroleum coke or pitch coke with as low ash as possible is selected, and the particle size of calcined coke powder needs to be particularly fine when producing pure graphite with fine structure; (2) The kneaded paste needs to be rolled several times, so that the binder and coke powder can be combined more effectively. After rolling, the slurry is subjected to secondary grinding and molding; (3)-Molding (cold molding or warm molding) is generally adopted; (4) Need to go through 2? Soak for four times and bake once or twice; (5) The gas-filled graphitization purification process was adopted, and the product was produced in 2000? At the high temperature of 2800℃, chlorine gas or freon gas is introduced to make chloride or fluoride formed by impurity elements volatilize and escape; when the furnace temperature drops to 1800℃, pure nitrogen gas is introduced to discharge excess chlorine gas or fluorine gas to achieve the purpose of purification.