A process for the manufacture of an aluminum oxide or zirconium oxide fiber comprising fiberizing a liquid containing lactic acid and an oxidizable compound selected from basic aluminum chloride, zirconium acetate and zirconium oxychloride and the resulting fibers. The liquid optionally also contains colloidal silica.
A process and apparatus for the manufacture of ceramic oxide fibers from solvent solution. The process comprises spinning a solution of a ceramic oxide precursor through openings having a diameter of from about 0.3 to about 1.5 millimeters, attenuating the resulting fibers with a stream of air to a diameter of less than 10 microns and heating the fibers in an oxygen atmosphere to form ceramic oxide fibers having a diameter of less than 5 microns. The apparatus comprises a hollow rotatable disc having about 0.3 to about 1.5 millimeter holes in its circumferential edge; means for rotatably mounting the disc; means for introducing a solution of a ceramic oxide precursor into the disc; means for rotating the disc to force solution through the openings in fiber form; means for attenuating the fibers with a stream of air; and means for calcining the fibers.
To provide a catalyst carrier holding material which is particularly useful for catalytic converters, by exhibiting heat resistance and high compression resistance in high temperature ranges, as well as excellent wind erosion resistance. The catalyst carrier holding material comprises inorganic fibers comprising alumina and silica, and the mullite ratio of the inorganic fibers is in the range of greater than 30% and less than 75%, and preferably in the range of 35% to 70%.
The present invention provides a novel hydrothermal process for producing zirconia sol comprising the following steps: mixing zirconium acetate with diluted glacial acetic acid to form a zirconium acetate/glacial acetic acid solution, wherein the molar ratio of glacial acetic acid to zirconium acetate as zirconia is in the range between about 7-20; and heating the zirconium acetate/glacial acetic acid solution to a temperature of at least 160.degree. C., thereby forming a zirconia sol.
Alumina fibers are prepared by a method comprising (a) forming aluminum methoxide from aluminum alkoxides using methanol; (b) recovering aluminum methoxide as a solid precipitate phase, washing to remove higher alcohols and drying to recover a powder; (c) reacting the recovered powdered aluminum methoxide with dilute hydrochloric acid to form aluminum chlorohydrate; then (d) concentrating the aluminum chlorohydrate solution under vacuum to desired viscosity.