METHOD OF PRODUCTION OF METALLIC SILICON Russian patent published in 2000 - IPC

FIELD: non- ferrous metallurgy; carbothermal method of production of silicon for photoelectronic industry, manufacture of solar batteries inclusive. SUBSTANCE: method consists in carbothermal reduction of silicon dioxide by organic reductant; liquid phenolic resin is used as organic reductant. Silicon production process includes three stages of heat treatment: from room temperature up to 160 C at pressure of 0.1 to 0.7 MPa, to 800 C at 1 hour delay, to 1700 C in inert gas atmosphere at two stages: to 1300-1400 C at pressure of 0.01 Pa and from 1300 --1400 C to 1700 C at pressure rising from 0.01 Pa to 0.1 MPa. Amount of admixtures in silicon dioxide does not exceed 190 ppm; content of admixtures in liquid phenolic resin does not exceed 90 ppm. EFFECT: improved level of interphase interaction of silicon dioxide and carbon reductant obtained from organic compound which results in facilitated procedure of production, reduced power requirements and increased output. 3 cl, 3 tbl