PROCEDIMENTO PER LA PRODUZIONE DI BETA-ALLUMINA

A method of making beta''-alumina comprises dispersing in a precursor of aluminum oxide a member of the group comprising sodium oxide and its precursors, and dispersing in the precursor of aluminum oxide a spinel stabilizer which is a member of the group comprising spinel-forming oxides and the precursors thereof, to form a mixture. The mixture is then heated to a temperature at which at least some of the precursor of aluminum oxide is converted to beta''-alumina. The precursor of aluminum oxide is one which, when calcined in air by itself, has a calcination product which, when subjected to X-ray diffraction, displays a predetermined X-ray diffraction trace. The X-ray diffraction trace is one whose peak with the highest intensity in the 2 (theta) range of 44 DEG -48 DEG and whose peak with the highest intensity in the 2 (theta) range of 63 DEG -69 DEG respectively have maximum intensities and integrated intensities which comply with equations (I) and (II): A/S is greater than 0.03 (I); and B/S is greater than 0.04 (II).