00000nam 2200000za 4500 9.840868 CaOODSP 20221107151941 cr ||||||||||| 170802s1972 oncad ob f000 0 eng d CaOODSP eng n-cn--- M38-8/116E-PDF M38-8/116 Wheat, T. A. Calcination of gibbsite [electronic resource] / T.A. Wheat, Mineral Processing Division. Ottawa : Information Canada, 1972. p. 43-48 : charts, ill. Reprint series ; RS 116 Cover title. "Reprinted from the Journal of the Canadian Ceramics Society, (1971), vol. 40, pp. 43-48." Historical publication digitized from print 2017 [by Natural Resources Canada]. Includes bibliographical references. "Data are presented showing the changes in physical properties which occur during the calcination of Bayer-process gibbsite at temperatures up to 1400°C. The various stages of the calcination were examined using differential thermal analysis, X-ray diffraction, low-temperature nitrogen adsorption, optical and electron microscopy, and particle-size distribution analyses. The morphology of the gibbsite aggregates was found to be unchanged up to ~ 1100°C, despite the development of several intermediate metastable phases. At higher temperatures, the original gibbsite pseudomorphs become microporous coincident with the development of finely divided alpha-alumina which is formed in a strain-free state. The crystal size and pore size increase with temperature between 1100 and 1400°C. The influence of the parent gibbsite structure on the morphology of the alpha-phase material is demonstrated in scanning-electron micrographs. The effect of various parameters on the milling of high-temperature calcines is also discussed"--Abstract, p. 43. gccst Ceramics gccst Minerals gccst Processing Canada. Natural Resources Canada. Canada. Department of Energy, Mines and Resources. Canada. Mines Branch. Reprint series - Dept. of Energy, Mines and Resources, Mines Branch ; RS 116 (CaOODSP)9.834843 PDF 2.92 MB https://publications.gc.ca/collections/collection_2017/rncan-nrcan/M38-8/M38-8-116-eng.pdf 300195