Thermal decomposition of Bayer precipitates formed at varying temperatures
Data(s) |
01/04/2010
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Resumo |
Bayer hydrotalcites prepared using the seawater neutralisation (SWN) process of Bayer liquors are characterised using X-ray diffraction and thermal analysis techniques. The Bayer hydrotalcites are synthesised at four different temperatures (0, 25, 55, 75 °C) to determine the effect on the thermal stability of the hydrotalcite structure, and to identify other precipitates that form at these temperatures. The interlayer distance increased with increasing synthesis temperature, up to 55 °C, and then decreased by 0.14 Å for Bayer hydrotalcites prepared at 75 °C. The three mineralogical phases identified in this investigation are; 1) Bayer hydrotalcite, 2), calcium carbonate species, and 3) hydromagnesite. The DTG curve can be separated into four decomposition steps; 1) the removal of adsorbed water and free interlayer water in hydrotalcite (30 – 230 °C), 2) the dehydroxylation of hydrotalcite and the decarbonation of hydrotalcite (250 – 400 °C), 3) the decarbonation of hydromagnesite (400 – 550 °C), and 4) the decarbonation of aragonite (550 – 650 °C). |
Formato |
application/pdf |
Identificador | |
Publicador |
Kluwer |
Relação |
http://eprints.qut.edu.au/31838/2/31838.pdf DOI:10.1007/s10973-009-0136-y Palmer, Sara J. & Frost, Ray L. (2010) Thermal decomposition of Bayer precipitates formed at varying temperatures. Journal of Thermal Analysis and Calorimetry, 100(1), pp. 27-32. |
Direitos |
Copyright 2010 Kluwer |
Fonte |
Chemistry; Faculty of Science and Technology |
Palavras-Chave | #030603 Colloid and Surface Chemistry #030600 PHYSICAL CHEMISTRY (INCL. STRUCTURAL) #030606 Structural Chemistry and Spectroscopy #030602 Chemical Thermodynamics and Energetics #thermal analysis, hydrotalcite, Bayer liquor, seawater neutralisation |
Tipo |
Journal Article |