Preparation of submicron size gamma lithium aluminate particles from the mixture of alumina sol and lithium salt by ultrasonic spray pyrolysis

Abstract

Gamma lithium aluminate particles of submicron size were directly prepared by ultrasonic spray pyrolysis from two different solutions. One was a colloidal mixture of alumina sol and lithium salt (S1), and the other was an aqueous solution of aluminum nitrate and lithium salt (S2). The influence of these two different types of solution on the purity of the crystalline phase and the morphology of the particles was investigated, The pure gamma lithium aluminate particles were prepared at 800 degrees C from the colloidal solution (S1) which was obtained from aluminum isopropoxide and lithium formate. The particles prepared from the colloidal solution (S1) had purer gamma phase than that of the particles prepared from the aqueous solution of aluminum nitrate and lithium salts (S2). The particles prepared from the aqueous solution of aluminum nitrate and lithium salt (S2) had smooth surfaces and low surface area (7 m(2)/g), whereas the particles prepared from the colloidal solution (S1) had rough surfaces and high surface area (45 m(2)/g). (C) 1996 Academic Press, Inc.