Kinetics Study of the Digestion of Magnesium Chloride Dihydrate in a Molten Salt Electrolyte

Abstract:

During the electrolytic reduction of magnesium, it is very important to understand the mechanism of the digestion of the magnesium chloride dihydrate granules in the molten electrolyte throughout the chlorination process. This work aimed to investigate the kinetics of this digestion process. The results showed that the granules digestion is happening in two stages. The first stage is very fast, hence, results in the formation of MgOHCl during the dehydration and the hydrolysis of magnesium chloride dihydrate in the interior of the granules. The kinetic results for the first stage was best modeled using shrinking core model where the surface reaction was the rate controlling step. The second stage was best modeled as a first-order homogenous reaction. The kinetic parameters for the two stages were determined along with the Arrhenius plots. The results of this kinetics study are essential for the mathematical modeling of the chlorination process of the magnesium chloride dihydrate granules.

• Periodical: Key Engineering Materials (Volume 865)
• Pages: 105-110
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.865.105
• Online since: September 2020
• Authors: Muhammad Tawalbeh*
• Keywords: Decomposition Kinetic, Electrolytic Reduction, Magnesium Production, Melt Chlorination

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