TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: The temperature at which the gaseous trichlorosilane is reacted with hydrogen is 1050-1250degreesC. The method further involves isolating the deposited silicon from the substrate; melting the deposited silicon; forming solid silicon from the melted deposited silicon; combining the melted deposited silicon with the silicon melt; and reacting gaseous trichlorosilane with hydrogen produces gaseous hydrogen chloride by-product. The gaseous hydrogen chloride by-product is added to metallurgical grade silicon to produce trichlorosilane. The method further involves: (d1) converting the gaseous silicon tetrachloride to silicon particles having an average primary particle size of less than or equal to 200 nm and an average agglomerate size of less than or equal to 500 microns; and (d2) converting the silicon particles to finely divided silicon having an average primary particle size of less than or equal to 200 nm and an average agglomerate size of greater than or equal to 500 microns. The step (d2) involves repeating step (d1) with the addition of the silicon particles obtained in a prior step (d1). The finely divided silicon is densified prior to forming a silicon melt. The densification of the finely divided silicon involves forming the finely divided silicon into pellets. The converting the gaseous silicon tetrachloride involves thermally decomposing the gaseous silicon tetrachloride, optionally in the presence of an inert diluent, in the presence of oxygen (0-100 ppm by weight). The thermal decomposition of gaseous silicon tetrachloride produces gaseous chlorine by-product which is reacted with hydrogen to produce hydrogen chloride. The hydrogen chloride produced from the by-product is added to silicon to produce trichlorosilane. The thermal decomposition of the gaseous silicon tetrachloride takes place in a reaction chamber into which is injected gaseous sodium chloride. The gaseous sodium chloride condenses and encapsulates the silicon to form sodium chloride-encapsulated silicon particles. The silicon is separated from the sodium chloride by washing with a liquid (preferably water or glycerin), by subjecting the sodium chloride-encapsulated silicon particles to sublimation, or by vaporization. The sublimation of the sodium chloride-encapsulated silicon particles is carried out at 500-1100degreesC. The converting the gaseous silicon tetrachloride involves reacting the gaseous silicon tetrachloride in the presence of a reducing agent in the presence of 0-100 ppm by weight oxygen. The method involves reaction of the silicon tetrachloride byproduct with sodium produces gaseous sodium chloride. The unreacted gaseous silicon tetrachloride is removed from the thermal decomposition reaction. The removed unreacted gaseous silicon tetrachloride is purified and utilized as feedstock for the step of converting the gaseous silicon tetrachloride by thermally decomposing the gaseous silicon tetrachloride, optionally in the presence of an inert diluent, in the presence of oxygen (0-00 ppm by weight). The conversion of the gaseous silicon tetrachloride is quenched by contact with an inert gas or hydrogen, or by expansion of gaseous reagents through a nozzle. Preferred Components: The carrier material and the substrate are removed with an oxidizing agent. The substrate is silicon supported on a carrier material. The carrier material and the substrate are graphite. The oxidizing agent is fuming nitric acid or chromosulfuric acid. The reducing agent is a vaporized alkali metal (preferably sodium). EXAMPLE - No suitable example given.