THE DEVELOPMENT OF TRACER CRYSTALS FOR INVESTIGATING GIBBSITE PRECIPITATION IN CAUSTIC ALUMINATE SOLUTIONS

Ilievski, D. and White, E.T.

Tracer crystals were developed to study the agglomeration, growth and residence time behaviour of gibbsite particles in continuous and batch crystallisation. Satisfactory tracer crystals were developed which contain detectable amounts of Zn and have the crystal structure of gibbsite. The method for manufacturing the tracers consisted of two steps. The first step was to co-precipitate the Zn(II) ion into a matrix of gibbsite. The second step was to grow gibbsite on the surface of the co-precipitate to a thickness in excess of 5 micron.