A Combined Soda Sintering and Microwave Reductive Roasting Process of Bauxite Residue for Iron Recovery

In this study an integrated process is presented as a suitable method to transform Fe<sup>3+</sup> oxides present in bauxite residue into magnetic oxides and metallic iron through a microwave roasting reduction, avoiding the formation of hercynite (FeAl<sub>2</sub>O<sub>...

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Bibliographic Details
Main Authors: Chiara Cardenia, Efthymios Balomenos, Pritii Wai Yin Tam, Dimitrios Panias
Format: Article
Language:English
Published: MDPI AG 2021-02-01
Series:Minerals
Subjects:
Online Access:https://www.mdpi.com/2075-163X/11/2/222
Description
Summary:In this study an integrated process is presented as a suitable method to transform Fe<sup>3+</sup> oxides present in bauxite residue into magnetic oxides and metallic iron through a microwave roasting reduction, avoiding the formation of hercynite (FeAl<sub>2</sub>O<sub>4</sub>). In the first step, all the alumina phases were transformed into sodium aluminates by adding sodium carbonate as a flux to BR and then leached out through alkali-leaching to recover alumina. Subsequently, the leaching residue was mixed with carbon and roasted by using a microwave furnace at the optimum conditions. The iron oxide present in the sinter was converted into metallic iron (98%). In addition, hercynite was not detected. The produced cinder was subjected to a wet high intensity magnetic separation process to separate iron from the other elements.
ISSN:2075-163X