Highly pure, crystalline barium-titanium-silicate prodn. - comprises mixing titanium- and silicon-components, reacting with barium hydroxide, drying, and calcining

摘要

Prodn. comprises a 2 stage process in which the Si- and Ti- components are mixed and reacted with Ba(0H)2 soln.. The exchange of the mixed Si- and Ti- components with the barium hydroxide soln. is carried out at a temp. of less than 323 K and at a pH of less than 13. The obtd. amorphous reaction prod. is calcinated at 1073-1273K, pref. 1173K after drying. USE/ADVANTAGE - The obtd. Ba2TiSi208 (Fresnoit) is used in hf, ultrasonic and laser applications. The 2-stage process ensures that no crystalline intermediates i.e. BaTi03, Ba0.Si02.H20 etc., are produced and reproducibly gives highly pure barium titanium silicate.