The evaluation of N-OSS (N-oleoyl sarcosine) as an efficient collector in the flotation of spodumene from albite at low temperature: Experimental tests and atom-level calculation

In this study, N-OSS was explored as an efficient collector in the flotation of spodumene from albite. The flotation behaviors were examined by micro-flotation tests and the interaction mechanisms were comprehensively uncovered from atomical scale. It indicated N-OSS could effectively collect spodumene from albite at low temperature and N-OSS was more inclined to adsorb on spodumene surface than that on albite surface, thus significantly expanding the hydrophobicity difference. X-ray photoelectron spectroscopy (XPS) analysis suggested that N-OSS chemically interacted with both Ca and Al active sites on Ca-activated spodumene surface. Whereas, it weakly adsorbed on Ca-activated albite. Density functional theory (DFT) calculation reconfirmed that the adsorption of N-OSS on Ca-activated spodumene surface was more favorable than that on albite surface. The strong adsorption on spodumene was due to the hybridization reaction between the O 2p orbitals of C-O and C=O groups of N-OSS with Ca 4s orbitals as well as Al 3s orbitals on spodumene surface. Nevertheless, N-OSS weakly interacted with Ca atoms on Ca-activated albite due to steric hindrance. N-OSS exhibited selective collecting ability at low temperature in the flotation of spodumene from albite compared with conventional collector, which has promising prospects in the low-temperature flotation of spodumene from albite.