Entrainment of quartz in flotation tests with MIBC frother

During passing gas bubbles through suspensions containing hydrophobic or/and hydrophilic particles, some mechanical carryover of particles to the froth layer always takes place. The entrainment of mineral particles is influenced by many parameters, mostly by the particle size and the concentration of the frother. The paper deals with influence of methylisobutylcarbinol (MIBC), a common and standard laboratory flotation tests frother, on the mechanical carryover of quartz, a typical gangue mineral component of ores. Entrainment tests were carried out in a laboratory Mechanobr flotation machine with quartz particles suspended either in water or frother solution. The mechanical recovery of quartz in the frother increased with time and reached plateau after about 20 minutes of flotation. The plateau level of quartz recovery depended on the frother concentration. Initially it is observed an increase of the plateau with frother concentration until it reaches the highest plateau level at about of 32 % of quartz recovery. The shape of flotation kinetics, the plateau level of the quartz entrainment after long (about 20 min) bubbling time and at sufficiently high concentration (above about 510-4 M MIBC) can be used as parameters to characterize the ability of frothers to entrainment of particles. In the studied system of quartz-MIBC-Mechanobr flotation cell at 20 min of flotation and 510-4 M of MIBC, the maximum entrainment is 32 %. These parameters can be useful for evaluation of the mechanical recovery of particles in flotation systems. Surface chemistry of frother interaction with minerals in relation to mechanical recovery of particles will be discussed