Abstract: Chlorosilanes such as dimethyldichlorosilane are hydrolyzed in a first super-azeotropic hydrochloric acid distillation column A to produce cyclosiloxanes, chlorosiloxanes, and hydrogen chloride gas. The cyclosiloxanes and the chlorosiloxanes are washed and separated according to their volatility in a second sub-azeotropic hydrochloric acid distillation column B, to produce a substantially chloride free volatile cyclosiloxane stream and a substantially chloride free non-volatile siloxane stream. The process is substantially chloride efficient.

Abstract: Chlorosilanes such as dimethyldichlorosilane are hydrolyzed in a first super-azeotropic hydrochloric acid distillation column A to produce cyclosiloxanes, chlorosiloxanes, and hydrogen chloride gas. The cyclosiloxanes and the chlorosiloxanes are washed and separated according to their volatility in a second sub-azeotropic hydrochloric acid distillation column B, to produce a substantially chloride free volatile cyclosiloxane stream and a substantially chloride free non-volatile siloxane stream. The process is substantially chloride efficient.

Abstract: A process is disclosed for preparing linear hydroxy end-terminated linear siloxanes comprising the steps of; a) mixing chlorosiloxanes having the formula ClR2SiO(R12SiO)xSiR2Cl  where x is an integer having a value from 1-10, each R and R1 is an independently selected monovalent hydrocarbon group, with volatile methyl siloxanes to form a solution of chlorosiloxanes in volatile methyl siloxanes; b) hydrolyzing the solution of chlorosiloxanes in volatile methyl siloxanes to form a hydrolysis mixture of reaction products; c) separating the hydrolysis mixture of reaction products into an aqueous phase and a siloxane phase comprising hydroxy end-terminated linear siloxanes and volatile methyl siloxanes; and d) recovering the hydroxy end-terminated linear siloxanes from the siloxane phase.

Abstract: An improved structured packing for use in a liquid-vapor contact column. More specifically in a structured packing for liquid-vapor contact where the structured packing comprises laterally orientated channels having peripheral openings, the improvement comprises substantially occluding the peripheral openings with a barrier film. The present invention also includes an improved liquid-vapor contact column comprising a column shell having positioned within a structured packing comprising an outer surface in non-occlusive proximation to the column shell and laterally orientated channels having peripheral openings through the outer surface, the improvement comprising substantially occluding the peripheral openings with a barrier film.