collectors are the main additives used to improve particle surfaces. they function as surfactants to selectively isolate and aid adsorption between the particles of interest and bubbles rising through the slurry. common collectors used in flotation are anionic sulfur ligands, which have a bifunctional structure with an ionic portion which shares attraction with metals, and a hydrophobic portion such as a long hydrocarbon tail. these collectors coat a particle’s surface with a monolayer of non-polar substance to aid separation from the aqueous phase by decreasing the adsorbed particle solubility in water. the adsorbed ligands can form micelles around the particles and form small-particle colloids improving stability and phase separation further.