Structural design and mechanistic evaluation of a novel collector for bastnaesite flotation: Insights from 3D-QSAR analysis

Abstract

Rare earth elements are strategically important resources, and the efficient flotation separation of bastnaesite and calcium-containing minerals is a significant technical challenge that must be addressed urgently in mineral processing. Herein, we report a collector with a novel structure, namely N-phenylethyl hydroxamic acid (NP-2), for bastnaesite flotation. We conducted an in-depth study of the structure–activity relationship of hydroxamic acid collectors in the flotation of bastnaesite using a three-dimensional quantitative structure–activity relationship method. Our findings indicate that NP-2 retains the hydroxamic acid group with exceptional selectivity, possesses highly regulated hydrophobicity, enhances the steric hindrance effect of the hydroxamic acid group, and introduces a novel synthetic route with the potential to become an efficient collector of bastnaesite. The flotation test results prove that NP-2 effectively separates bastnaesite from fluorite. Investigation of the adsorption mechanism indicates that NP-2 possesses a strong targeted chelating effect on the bastnaesite surface. Thus, this study presents novel concepts for the optimization of collectors for the flotation of rare earth minerals, and establishes a theoretical framework for the future development of collector design, moving from empirical to precise quantitative optimization.

Keywords

Bastnaesite / Flotation / N-phenylethyl hydroxamic acid / Quantitative structure–activity relationship / Density functional theory

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