Advances in reagent systems and mechanisms for desilication from bauxite via flotation

Abstract

The imbalance between supply and demand for bauxite resources, coupled with inadequate refining process compatibility, poses significant challenges in fulfilling the raw material requirements for the Bayer process, thereby severely hindering the sustainable development of the aluminum industry in China. Consequently, low alumina-to-silica ratio bauxite necessitates pretreatment to enhance its quality, ensuring compliance with the feedstock specifications of the Bayer process. Flotation technology, emerging as an efficacious desilication pretreatment approach, has garnered considerable attention and demonstrated substantial application potential in bauxite desilication. This study comprehensively analyses the chemical composition and mineralogical characteristics of bauxite, systematically elucidating and contrasting the advantages of direct and reverse flotation collectors and auxiliary reagents. Furthermore, it delves into the distinct mechanisms of action these reagents exhibit with diaspore and aluminosilicate minerals. Building upon this foundation, the study offers insights and projections for future research endeavours in bauxite flotation desilication, which holds profound theoretical significance in addressing the trend of depleting bauxite resources in China.