MONITORING THE MORPHOLOGY OF ALUMINA TRIHYDRATE IN A CONTINUOUS PRECIPITATION CIRCUIT, USING X-RAY DIFFRACTION (XRD).
Loughlin, B.P.
XRD is used to determine the ratio of the (002) to (110)+(200) diffraction line intensities of gibbsite. This parameter, termed the Gibbsite Crystallinity (Gc) in this paper, is a function of the morphology of hydrate, viz, the proportion of radial to mosaic particles in the bulk sample. Measurement is made on the ground and pellet pressed hydrate.
A good agreement was found between this method of morphology analysis to that of thin section polarised light microscopy.
Laboratory test work, and analysis of plant data over many months has shown the Gc parameter to correlate well with the degree of particle breakdown on calcination.
The advantages and convenience of Gc as a process monitoring tool are discussed and illustrated.