Abstract: A process for shaping parts from ceramic powder that comprises the steps of (1) forming a concentrated mixture in excess of 40% ceramic solids by volume, the mixture comprising ceramic powder, a gel forming material chosen from the class of polysaccharides known as "agaroids", and a gel forming material solvent and being formed in a blender that provides a shearing action and is heated to raise the temperature of the mixture to about 70.degree. C. to 100.degree. C.; and (2) molding the mixture at a temperature sufficient to produce a self-supporting structure comprising the powder and gel. The parts exhibit excellent green strength and are rapidly fired without cracking, distortion or shrinkage problems.

Abstract: A ceramic element of a zirconia oxygen sensor is shaped from a powder mixture. The mixture, comprising a ceramic powder having an average particle size less than or equal to 1 micrometer, a gel-forming material and a gel forming material solvent, is molded at a temperature and pressure sufficient to produce the ceramic element having a density of at least 5.5 g/cm.sup.3.

Abstract: Inorganic metal oxides having high surface area and pore volume are prepared by spray drying. The admixture which is spray dried to yield the metal oxides is produced from reactants comprising at least one hydrolyzable metal compound, a sufficient amount of water to at least partially hydrolyze the metal compound and an organic solvent. The admixture is supplied as a plurality of droplets to a reaction zone operated under conditions of temperature and pressure below the critical temperature and pressure of the reactants but sufficient to produce a product comprising metal oxide powders and a gas comprising organic solvent vapors. The powders are separated from the gas in a known fashion and collected. Spray drying of non-aqueous systems unexpectedly produces metal oxides having properties generally intermediate conventionally produced oxides and aerogels.

Abstract: Inorganic metal oxides having high surface area and pore volume are prepared by spray drying. The admixture which is spray dried to yield the metal oxides is produced from reactants comprising at least one hydrolyzable metal compound, a sufficient amount of water to at least partially hydrolyze the metal compound and an organic solvent. The admixture is supplied as a plurality of droplets to a reaction zone operated under conditions of temperature and pressure below the critical temperature and pressure of the reactants but sufficient to produce a product comprising metal oxide powders and a gas comprising organic solvent vapors. The powders are separated from the gas in a known fashion and collected. Spray drying of non-aqueous systems unexpectedly produces metal oxides having properties generally intermediate conventionally produced oxides and aerogels.