Abstract
The economic necessity to achieve high precipitation yields and tough alumina must be balanced against another important quality consideration — occluded soda. Although there are a number of publications that develop hypotheses for the mechanism of soda incorporation, and some that give mathematical relationships to describe the rate of soda incorporation, none attempt to do this with any reference to known physical and chemical phenomena associated with the hydrate (gibbsite) growth mechanism.
The present work describes soda incorporation as a function of growth rate and develops a hypothesis that crystal defects are traping sites for sodium ions. The incorporation of sodium ions into gibbsite crystals is a direct consequence of the growth mechanism. A mathematical model for incorporation is developed along basic statistical mechanical principles and the contribution of organic carbon towards defect generation is explored.
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Vernon, C., Loh, J., Lau, D., Stanley, A. (2016). Soda Incorporation During Hydrate Precipitation. In: Donaldson, D., Raahauge, B.E. (eds) Essential Readings in Light Metals. Springer, Cham. https://doi.org/10.1007/978-3-319-48176-0_83
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DOI: https://doi.org/10.1007/978-3-319-48176-0_83
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