Flotation behavior, adsorption mechanism and separation application of polyetheramine in quartz-mica system under acid-free and alkali-free conditions

This study investigates the novel application of polyetheramine (PEA) as an eco-friendly collector for quartz-mica flotation separation under pH-neutral conditions, focusing on its flotation behavior, adsorption mechanisms, and separation efficacy compared to the conventional dodecylamine (DDA). The single mineral flotation demonstrated the superior selectivity of PEA, achieving an 87 % flotation recovery differential (93 % for quartz vs. 6 % for mica), significantly outperforming the 26 % differential of DDA. The mixed minerals (mass ratio: Quartz/Mica = 2/1) flotation shows that PEA can effectively separate the quartz and the mica. Composition analysis shows that the flotation product phase composition is consistent with the single mineral. The quartz content in the 2nd froth product reaches 95.88 % (78.86 % recovery). The mica content in the sink product reaches 71.19 % (91.09 % recovery). Adsorption test analysis indicates that PEA and DDA are mainly adsorbed on minerals by electrostatic adsorption through the ─NH 3 + group. DFT calculations show that the difference in PEA adsorption energy between the quartz and the mica surfaces is 1.52 eV (DDA is only 0.2 eV). Based on the above results we analyzed the adsorption and separation mechanisms. The findings establish PEA as a sustainable alternative to conventional pH-dependent collectors, eliminating acid/alkali consumption while maintaining high separation efficiency.