James Malumbo Mwase, Michail Vafeias
This study investigates applying the principles of the long-discontinued Pedersen process as a possible route for producing metallurgical grade alumina from low-grade and secondary feed materials. The investigation focused on the hydrometallurgical steps in the process, namely leaching, desilication, and precipitation, and adapting it to valorize bauxite residue. The test material used was a calcium–aluminate slag made by the smelting-reduction of a mixture of bauxite residue (dewatered red mud) and a calcium-rich bauxite beneficiation by-product. Samples of the slag were leached in a 1 L jacketed glass reactor with Na2CO3 solution, varying Na2CO3 concentration and leaching time. Additionally, different approaches to leaching involving mechanical treatment of the leached slag and re-leaching using either fresh or recycled solution were also explored. The desilication step was carried out by treating the leachate solution with powdered CaO, varying the amounts of CaO used. Finally, the desilicated leach solution was sparged with a CO2 gas mixture, after which the precipitate was allowed to age in the solution.
@article{34c03995-ccc5-4c4f-a824-9cc89d4aa164,
title={Investigating Aluminum Tri-Hydroxide Production from Sodium Aluminate Solutions in the Pedersen Process},
author={James Malumbo Mwase and Michail Vafeias},
year={2022},
language={en}
}TY - JOUR TI - Investigating Aluminum Tri-Hydroxide Production from Sodium Aluminate Solutions in the Pedersen Process AU - James Malumbo Mwase AU - Michail Vafeias PY - 2022 LA - en ER -
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