Patent ID: 7927984
Filing Date: 2011-04-19
Classification: B01J,C01B,F23C,Y02P

Abstract:
1. A process comprising: 1) feeding a deposition gas comprising hydrogen and a silicon monomer into an internal region of a fluidized bed reactor, where the silicon monomer is selected from SiH 2) feeding an etching gas consisting essentially of SiCl wherein the amount of the silicon monomer in step 1) is sufficient to deposit silicon on fluidized silicon particles in a reaction zone located above the heating zone of the fluidized bed reactor, and the amount of SiCl 4 in step 2) is sufficient to etch silicon from the wall of the fluidized bed reactor; and, where a vent gas stream from one or more Siemens reactors is separated in equipment comprising a distillation column to form at least a portion of the deposition gas and at least a portion of the etching gas, after leaving the one or more Siemens reactors and before entering the fluidized bed reactor.