A New Method to Determine Entrainment in Collectorless Flotation of Sulphide Minerals

Separation of minerals by flotation is based on the differences of surface properties between the valuable minerals and the gangue. However, some particles float by entrainment mechanism which is a nonselective process. There are different methods to determine the amount of particles which is floated by entrainment. In this paper a new method applied to determine entrainment in collectorless flotation of chalcopyrite of Mazraeh mine. Effect of parameters including impeller speed, pulp density, time, frother amount was investigated for chalcopyrite entrainment. In collectorless flotation, by controlling pulp potential (Eh), the hyrophobicity of particles prevented and so the net fraction of particles moved to concentrate by entrainment were calculated. Under optimum conditions of pulp density = 10%, it was observed that impeller speed = 908rpm, frother amount = 20g/t and flotation time equal to 1.1min, chalcopyrite entrainment minimize to 0.6 %.