Reagent types and action mechanisms in ilmenite flotation: A review

Abstract

Ilmenite is an essential mineral for the extraction of titanium. Conventional physical separation methods have difficulty recovering fine ilmenite, and dressing plants have begun applying flotation to recover ilmenite. The interaction of reagent groups with Ti and Fe sites on the ilmenite surface dramatically influences the ilmenite flotation. However, the investigation on Fe sites has received more attention because the activity of Ti is lower than that of Fe. For the activators on ilmenite flotation, most are metal ions but typically lead ions. The metal ions of activators promote ilmenite flotation by increasing the active sites on the ilmenite surface. Combined reagents have a better selective separation of ilmenite than single reagents due to their synergistic effect. Combining the lead ion (Pb²⁺) and the benzyl hydroxamic acid (BHA) into a Pb—BHA complex has a marked effect on ilmenite flotation, which puts forward a new idea of developing combined reagents for ilmenite flotation. This review considers reagent types and action mechanisms in ilmenite flotation. On the basis of the analysis of previous research, a brief future outlook of reagent types and action mechanisms in ilmenite flotation is also proposed in this study.

Keywords

ilmenite / flotation / reagent / action mechanism / combined reagents

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