Production of spherical granules of alumina with controlled porous structure

Abstract

Structural changes of aluminium hydroxides at main technological stages are studied to produce spherical alumina with a given volume of pores. Two hydroxides essentially different in morphology, particle size and type of bond between primary particles have been synthesized. A collected of alumina with varied volumes of pores and effective radii has been obtained using a mixture of hydroxides of both types. We show how to calculate the volumes of meso- and macropores as well as the specific surface area of alumina and its precursors on the basis of the characteristics of each hydroxide and their ratio in the mixture.