It is challenging to remove feldspar from spodumene at low temperature due to the poor collecting ability and selectivity of conventional collector. In this work, Glycolic acid ethoxylate oleyl ether (GAEOE) was evaluated as a low-temperature resistant collector in the flotation separation of spodumene and feldspar. The flotation performances and the interfacial interaction mechanisms were comprehensively investigated. Micro-flotation experiments showed that GAEOE could realize the efficient separation between spodumene and feldspar at low temperature, producing high-quality concentrate with Li 2 O grade and recovery reached 6.02% and 81.22%, respectively. Contact angle, induction time and bubble-mineral interaction force measurements proved that GAEOE significantly increased the adhesion force and attachment probability between air bubbles and spodumene, while it exerted negligible influence on feldspar. Zeta potentials and in situ microcalorimetry tests confirmed the stronger affinity of GAEOE toward Ca-activated spodumene than feldspar. Adsorption capacity and turbidity measurements revealed that GAEOE exhibited more stable adsorption with low sensitivity to temperature changes than sodium oleate (NaOL), due to the better solubility and superior dispersion stability at low temperature. XPS and DFT analysis revealed a stable bidentate configuration involving synergistic interactions between the O atoms of C–O and C O groups within GAEOE and Al as well as Ca sites on Ca-activated spodumene surface. These results suggested GAEOE was a promising alternative for conventional fatty acid collectors for spodumene flotation in temperature-sensitive environment.
Shao et al. (Fri,) studied this question.