Investigating the effects of particle size and dosage of talc nanoparticles as a novel solid collector in quartz flotation

In this study, hydrophobic talc nanoparticles were applied as a novel class of solid flotation collector. The aim of this work was to understand the effect of talc nanoparticles size and dosage on the quartz flotation recovery. X-ray analysis, dynamic light scattering, and scanning electron microscopy were conducted. Flotation tests were performed in modified a Hallimond flotation cell. The Zeta potential measurement identified the pH value of 1.5 as the best condition for nano-talc powders to be electrostatically adsorbed on the quartz particle surfaces. Talc particles were adsorbed onto the hydrophilic quartz particles to encourage the air bubble attachment and improve the quartz flotation recovery. It was found that as the quartz particle size decreased, the amount of quartz flotation recovery increased. Talc size reduction from 567 nm to 235 nm, decreased the amount of required talc from 45 to 1.7 kg/t within 30 minutes of the flotation time span, and achieved a recovery of more than 90%. Practically, it was demonstrated that by using smaller talc nanoparticles, it was possible to decrease the talc dosage to obtain a similar level of quartz recovery over the same flotation time span and pH.