The heterogeneous azeotropic distillation technique has been successfu
lly applied to the preparation of ultra-fine sinterable zirconia powde
r having >98% of the theoretical density at 1200 degrees C. The mechan
ism of azeotropic distillation of n-butanol with a hydrous gel to prev
ent the formation of ''hard'' agglomerates has been investigated by TG
-DTA-MS and FT-IR techniques.