Abstract: Magnetic separators are used for treating silicon-containing materials from chlorosilane reactors to remove magnetically influenced components in the silicon-containing materials. The removal of such impurities allows for enhanced reactivity of the silicon-containing materials in processes wherein the silicon-containing materials are raw materials for the production of silicon based compounds, such as, for example, basic alkylhalosilanes such as dimethyldichlorosilane, methyldichlorosilane, and other chlorosilanes such as trichlorosilane, which chlorosilanes are useful in the preparation of valuable silicon-containing products.

Abstract: A method for recovering particulate silicon essentially free of silicon containing compounds from a by-product stream containing metal salts and high-boiling silicon containing compounds having a boiling point higher than the sublimation temperature of the metal salts. The method comprises first separating the particulate silicon and other solids from the by-product stream by a method such as filtration. The particulates are then washed with a solvent having a boiling point lower than the sublimation temperature of the metal salt, thereby separating residual high-boiling silicon containing compound from the particulate silicon and other solids. The particulate silicon and other solids are then recovered in a dried form, essentially free of silicon containing compounds, by spray drying at a temperature lower than the sublimation temperature of the metal salt.

Abstract: A method for grinding silicon metalloid comprising grinding silicon metalloid in the presence of an effective amount of a grinding aid selected from the group consisting of carboxylic acids comprising at least 8 carbon atoms, alkali metal salts of carboxylic acids comprising at least 8 carbon atoms, and polydiorganosiloxanes.