Process for preparation of water-free oxide material

摘要

The specification discloses new and improved processes for forming water-free metal or non-metal oxide materials, which may then be melted and formed into optical components in vitreous or crystal form, which are free of the hydrogen-impurity absorption in the near infrared wavelength range. In one process, a water-free oxide is prepared by reacting a chosen nonpolar compound containing the desired metal or non-metal with an aprotic oxygen-containing compound to form the oxide as a precipitate in a chosen aprotic nonaqueous liquid solvent which provides a water-free environment during the formation of the oxide, to prevent the inclusion of water and water-derived impurities in the oxide as formed. Then the oxide-containing precipitate is subjected to a reactive atmosphere process by exposing the powder to a chosen gas phase reactive atmosphere comprising atomic halogen at a predetermined elevated temperature for a predetermined period of time, to remove traces of water and water-derived impurities from the oxide.