Method for the elimination of boron impurities in metallurgical silicon

摘要

A process for the elimination of boron impurities in metallurgical silicon, comprising the steps of:First step, acid purification: metallurgical silicon powder 6 ~ 48 hours is immersed in acid and then washed, as well as heat dried;Second step, heat oxidation: silicon powder, has already been cleaned in the first step acid, washed and heated, is in the reactor to 300°C. ~ 700°C. and the oxidizing agent is brought, in order to provoke a oxidation, wherein the reaction time 6 ~ 72 hours;Third step, dipping: in the second step has already been heat oxidized silicon powder, 1 ~ 6 hours in water or acid and then purified with water, immersed;Fourth step, jaws: the already immersed and purified silicon powder, in the case of 100°C. ~ 300°C. 6 ~ 24 hours, is baked.