A A REVIEW OF MODERN FLOTATION COLLECTORS FOR TUNGSTEN MINERALS: FROM BIFUNCTIONAL MOLECULES TO DFT-GUIDED DESIGN (REVIEW)

Abstract

The flotation efficiency of tungsten minerals depends largely on the structure of the collector and the nature of its adsorption on the mineral surface. Traditional fatty acids, hydroxamates, and organophosphorus reagents are well studied; however, their limited selectivity stimulates the development of more complex molecular systems. The purpose of this review is to examine current developments in the collector design for scheelite and wolframite, focusing on the bifunctional, multifunctional, and DFT-guided approaches. A conditional division of the collectors into generations is proposed: from traditional and chelating reagents to bifunctional and multifunctional systems and further to rationally designed collectors, using DFT and molecular modeling. This review examines the collectors containing various combinations of active groups, including amine–hydroxyl, thioether–hydroxamate, bis-hydroxamate, amino–hydroxamate, amidoxime–phosphonate, and hydroxamate–phosphonate systems. Their interactions with the surface Ca, Fe, Mn, and W sites are discussed, as well as the roles of electrostatic attraction, coordination bonding, hydrogen bonding, and hydrophobicity. Particular attention is paid to the increasing application of the density functional theory (DFT), molecular dynamics, electronic structure analysis, and hydrophobicity calculations in the collector design. The current research shows that the computational methods are increasingly being used not only to elucidate the adsorption mechanisms, but also to optimize spacer length, electron donation capacity, hydrophobicity, and ligand combinations prior to or in parallel with the experimental validation. This review focuses on the studies published between 2020 and 2026, with the earlier studies included where necessary to understand the background to the development of the modern approaches to the collector design.