PREPARATION OF MONODISPERSE AND SPHERICAL ZIRCONIA POWDERS BY HEATING OF ALCOHOL-AQUEOUS SALT-SOLUTIONS

A novel method is demonstrated which yields a spherical ZrO2 powder of narrow size distribution through heating of a zirconyl chloride solution with an alcohol-mater mixture as the solvent. The kind and composition of the solvent mixture greatly influenced the behavior of the precipitation and the morphology of the resulting particles, When l-propanol or 2-propanol was employed as the alcohol of the solvent mixture, the resulting particles had a spherical shape and a narrow size distribution. The particle size and the particle agglomeration level could be controlled by the amount of hgdroxypropyl cellulose (HPC) in the solution, As-prepared amorphous powder was crystallized to a mixture of metastable tetragonal phase and monoclinic phase at about 460 degrees C. The metastable tetragonal phase was converted to the monoclinic phase as the calcination temperature was increased. After calcination, the spherical shape of the zirconia powder was retained, while its particle size was decreased slightly.