METHOD OF PRODUCING HIGH PURITY SILICON POWDER FROM MIXTURE OF SILICON DIOXIDE AND ALUMINIUM Russian patent published in 2018 - IPC C01B33/23 C30B29/06 B22F9/16 B22F9/04 

FIELD: chemistry.

SUBSTANCE: high-purity silicon powder is produced by the thermal recovery of silicon dioxide to elemental silicon using fine aluminium, while the recovery process in the electro-thermal reactor is carried out in two stages, at the first of which the temperature is 900-1000°C with aging for 3-5 mines, at the second stage the reactor temperature is increased up to 1100°C with aging for 60-90 s, then a division of silicon and aluminium oxide after crushing the pellets is carried out by the flotation method. Impurities remain largely in the matrix of aluminium oxide and do not convert to silicon.

EFFECT: environmentally safe production of high purity silicon by carrying out the process using the alumotermy method.

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