Properties of Alumina Powder Prepared by Precipitation Method(I): Aluminum Hydrate

,; ,; ,; ,

J. Korean Ceram. Soc. > Volume 25(2); 1988 > Article

Journal of the Korean Ceramic Society 1988;25(2): 111.

침전법으로 제조한 Alumina 분말의 특성(1): 알루미늄 수산ulcorner루

홍기곤, 이홍림

연세대학교 공과대학 요업공학과

Properties of Alumina Powder Prepared by Precipitation Method(I): Aluminum Hydrate

ABSTRACT

Aluminum hydrates were prepared by precipitation method using Al2(SO4)3$.$18H2O as a starting material and NH4OH as precipitation agent. The phases of aluminum hydrate were changed from amorphous aluminum hydrate to pseudo-boehmite of AlOOH form and bayerite, gibbsite, hydragillite and norstrandite of Al(OH)3 form with increasing pH. As pH increased, agglomeration phenomena were reduced. Aluminum hydrates of AlOOH and Al(OH)3 form represented dehydration of structural water near 175$^{circ}C$ and 385$^{circ}C$, and 280$^{circ}C$, respectively. As the ratio of Al(OH)3 to AlOOH increased, specific surface area was reduced.