Mechanism study of solid microbubble enhanced flotation of fine cassiterite

The efficient flotation recovery of fine cassiterite is one of the challenges currently facing the effective utilization of resources. Previous studies have primarily focused on methods such as mineral pretreatment to enhance the flotation recovery of fine cassiterite. However, these approaches often complicate the flotation process. Thus, this study pioneers the introduction of solid microbubbles (SMB) as carriers to augment the flotation response of fine cassiterite. The microflotation experimental results indicate that, with the addition of sodium oleate (NaOL) and SMB, the flotation recovery of fine cassiterite increased from 59.99% to 68.72%, outperforming the effect of using the collector NaOL alone. Characterization analyses using Zeta potential, FTIR, and XPS revealed that SMB, due to its hydrophilic surface, does not easily adsorb directly onto the cassiterite surface. However, after the addition of NaOL, SMB is able to effectively adsorb onto the cassiterite surface. Further analysis reveals that SMB first undergoes chemisorption with NaOL, forming SMB with hydrophobic carbon chains. Subsequently, these hydrophobized SMB physically interact with the cassiterite surface, which has adsorbed NaOL, resulting in the formation of hydrophobic aggregates. This process enhances the flotation recovery of cassiterite. This study is the first to discover that NaOL serves a dual role, acting both as a hydrophobic modifier for SMB and as a collector for cassiterite. The key mechanism of interaction between the two hydrophobic aggregates and fine cassiterite through hydrophobic forces provides novel research insights and theoretical foundations for the efficient development and utilization of fine mineral resources.