A dehydration method in accordance with an embodiment of the present invention includes: a first dehydration step of bringing hydrogen chloride gas (21) and concentrated sulfuric acid (13A) into contact with each other; and a second dehydration step of bringing hydrogen chloride gas (21A) that has been obtained through the first dehydration step into contact with concentrated sulfuric acid (13B). A concentration of the concentrated sulfuric acid used in the second dehydration step is higher than a concentration of the concentrated sulfuric acid used in the first dehydration step.

The invention relates to a process for the production of monosilanes of formula H4-nSiCln with n being 2, 3 or 4 comprising the step of subjecting a starting material composition comprising one or more disilanes with formula HxSi2Cl6-x containing at least one Si—H bond and optionally further silanes, in particular the side-product mixture of the Siemens Process or fractions thereof, to a reaction with a reaction-promoting agent chosen from—ether/HCI solutions—amines, phosphines, or mixtures thereof—ammonium halides, phosphonium halides, or mixtures thereof at temperatures below 200° C.

Erosion, caused by deposition of aluminum chloride, of the inner surface of a side wall of a pipe is reduced. A trichlorosilane production method includes a distillation step (S3) in which a discharge liquid (10) discharged from a distillation column (4) is caused to flow through an inner space (19) of a second pipe (100) having a side wall (12) of which the inner surface (15) is covered with a ceramic layer (13), so that the discharge liquid (10) is recovered from the distillation column (4).

The invention relates to a method for cleaving silicon-silicon bindings and/or silicon-chlorine bindings in monosilanes, polysilanes, and/or oligosilanes. According to the invention, the monosilane, polysilane, and/or oligosilane is dissolved or suspended in an ether or in an ether-hydrochloric acid solution. Said method is used for example for preparing halogenated oligosilanes from halogenated polysilanes and for preparing siloxanes from organochlorosilanes and chlorinated monosilanes. Said method is particularly simple to carry out and as a result is economical.

The lifetime of a fluidized bed reactor containing silicon particles, for the production of chlorosilanes is greatly extended by armoring at least a portion of the reactor shell interior wall with expanded metal coated with a cement containing ceramic particles.

A method for producing amorphous silica includes: a pretreatment process of pulverizing vegetable material to obtain a silica source; a burning process of burning the silica source and extracting silica; and a purification process of removing carbon from burning material obtained in the burning process. The burning process includes a heating process of supplying an inert gas into a chamber and heating the silica source in the chamber in a plasma atmosphere.

Yield of products of increased purity from a fluidized bed reactor where silicon is produced or consumed is enhanced by purging with inert gas, purging with hydrogen gas, and purging with a chlorosilane-containing gas. The purging with hydrogen is conducted at an elevated temperature.

The invention relates generally to heaters and methods of using the heaters. In certain embodiments, a heater includes a pressure shell having a cylindrical heating cavity, an annular heat shield disposed within the cylindrical heating cavity, and at least one heating element disposed within an interior volume of the annular heat shield. In another embodiment, a method of preparing a trichlorosilane includes introducing a reactant stream comprising silicon tetrachloride into a heater, passing electrical current through a heating element to heat the reactant stream, and introducing the heated reactant stream into a reactor.

The lifetime of a fluidized bed reactor containing silicon particles, for the production of chlorosilanes is greatly extended by armoring at least a portion of the reactor shell interior wall with expanded metal coated with a cement containing ceramic particles.

The invention relates to a method for cleaving silicon-silicon bindings and/or silicon-chlorine bindings in monosilanes, polysilanes, and/or oligosilanes. According to the invention, the monosilane, polysilane, and/or oligosilane is dissolved or suspended in an ether or in an ether-hydrochloric acid solution. Said method is used for example for preparing halogenated oligosilanes from halogenated polysilanes and for preparing siloxanes from organochlorosilanes and chlorinated monosilanes. Said method is particularly simple to carry out and as a result is economical.