Influence of MIBC on the surface-air nucleation and bubble-particle loading in graphite froth flotation

•MIBC can increase the air nucleation probability on graphite surfaces.•MIBC can enhance the stability of bubbles to avoid particles detachment.•The particle load of nucleation bubbles and carrying bubbles can be increased by MIBC.•The percentage of agglomerates composed of nucleation bubbles and particles can be improved by MIBC.