Hydrophobic agglomeration of rhodochrosite fines in aqueous suspensions with sodium oleate.

Hydrophobic agglomeration of rhodochrosite fines in aqueous suspensions with sodium oleate has been investigated through wettability measurement, optical microscopy observation, laser-based particle size detection, micro-flotation test, zeta potential measurement in this work. The experimental results indicated that the hydrophobicity of rhodochrosite was a dominant factor for the hydrophobic agglomeration. And a higher sodium oleate concentration could contribute to bigger agglomeration particle size and more regular agglomerates. The increased apparent particle size of minerals through hydrophobic agglomeration interaction was conducive to the micro-flotation recovery improvement of rhodochrosite fines in spite of a simultaneous increase in the negative zeta potential of rhodochrosite, meaning that the chemical adsorption was the primary reason between sodium oleate and rhodochrosite. Furtherly, the data calculated from extended DLVO theory was also convinced that hydrophobic interaction between the particles increased much more strongly than electrostatic repulsion from the adsorption of sodium oleate. Schematic diagram of rhodochrosite hydrophobic agglomeration induced by NaOL. Unlabelled Image • Morphology changes of rhodochrosite agglomerates were investigated. • Correlate agglomeration with hydrophobicity, flotability and surface charge. • Sodium oleate could chemically adsorb on the surface of rhodochrosite. • Extended DLVO theory demonstrated the interaction energy between particles. [ABSTRACT FROM AUTHOR]