Electrostatic formation of ceramic membranes using CVD ultra-fine particles

Abstract A new method for forming a ceramic membrane has been devised. Ultrafine particles of silicon nitride synthesized by thermally activated CVD (Chemical Vapor Deposition) were deposited on the outer wall surface of a porous ceramic tube (substrate) by an electrostatic force and sintered in an inert gas atmosphere. The ceramic-made electrode assembly has been used for charging ultra-fine particles efficiently by surface discharge. A new ceramic membrane with a three-dimensional network similar to a fiber filter was obtained by this method. Its effective pore size was found to be around 0.2–1.0 μm in diameter with high porosity.