Process for manufacturing active silicon powder for the preparation of alkyl- or aryl-halosilanes

摘要

A process for the preparation of active silicon powder for use in the Rochow reaction consisting of grinding metallurgical silicon to a particle size less than 350 &mgr;m in the presence of at least one catalyst and/or reaction promoter, in order to deposit this (these) element(s) on the grain surface, and an active silicon powder with a particle size of less than 350 &mgr;m, with 0.01 to 0.1 g/m.sup.2 of copper, and/or 0.003 to 0.03 g/m.sup.2 of tin, and/or 0.003 to 0.03 g/m. sup.2 of phosphorus on the surface of the grains, for use in the Rochow reaction. The reactivity and selectivity of the powder are improved, and it has a shorter reaction incubation time.