Vorbereitung von Kontaktmassen für Alkylhalosilan Herstellung und Verfahren zur Herstellung von Alkylhalosilan

Alkylhalosilanes are produced by first fluidizing a metallic silicon powder with an inert gas, preheating the silicon powder at a temperature between 200 DEG C and a steady reaction temperature while keeping the silicon powder fluidized, adding a copper catalyst to the preheated silicon powder to form a contact mass, and feeding an alkyl halide into the contact mass whereby the alkylhalosilanes are formed by direct synthesis. This process prevents the copper catalyst from being sintered by thermal hysteresis and activates a high catalysis on the contact mass at the start of reaction. The desired dialkyldihalosilane can be produced at a high selectivity.