Process for removing impurities from residual silicon powder

摘要

A process for recovering and recycling elementary silicon from a direct process organohalosilane reactor system is provided, comprising the steps of analyzing a portion of effluent contact mass, such as the silicon fines from a secondary cyclone with a particle size distribution analyzer, determing the fines fractions containing the relatively greatest amounts of impurities and segregating a relatively impure fine fraction from a purer coarse fraction with the aid of an aerodynamic centrifugal classifier.