Effect of the Network Structure of Serpentine on Pyrite Flotation

In the process of sulfide ore beneficiation, layered silicate minerals, such as serpentine, tend to degrade the flotation effect. In order to fully understand the influence and mechanism of serpentine on pyrite flotation, an artificial mixed ore of pyrite–serpentine–quartz was used in this paper. The results showed that as the serpentine content increased, the recovery of pyrite decreased, along with the decrease in the flotation rate constant. The decrease in the flotation rate constant and concentrate grade was associated with possible slime coating and increased gangue transport to the concentrate at lower serpentine contents (≤30 wt.%). Mg distribution further confirmed that a considerable proportion of serpentine was reported to the concentrate. With the addition of serpentine, the pulp transitioned into a non-Newtonian fluid, accompanied by an increase in yield stress. The increases in pulp viscosity and structural resistance were associated with the network structure of serpentine. The development of E-F and E-E network structures was associated with higher apparent viscosity and yield stress, thereby contributing to the deterioration in flotation kinetics. This study provides a guideline for controlling the flotation process containing serpentine minerals.