A study for the experiment and mechanism of flotation separation of chalcopyrite and pyrite under the low alkalinity condition

In the flotation separation of chalcopyrite and pyrite, traditional depressants such as lime often cause environmental problems such as the difficulty for treating tailings and wastewater produced by the flotation process. Therefore, it is necessary to develop an environmentally friendly and efficient flotation depressant that can be used to reduce the dosage of lime in the flotation process. In this study, by taking the micro-flotation experiments, contact angle measurements, Zeta potential measurements, Fourier transform infrared spectrometer tests, X-ray photoelectron spectroscopy and surface adsorption experiments, we have studied the selective depression mechanism of an newly developed organic-inorganic mixed agent containing thiourea (OIMA) on the flotation separation of pyrite and chalcopyrite. The results of micro-flotation experiments show that the OIMA had a significant depression effect on pyrite, but an unobvious effect on chalcopyrite. The contact angle measurement results indicate that the hydrophilicity of pyrite can be significantly enhanced by the OIMA even in the presence of collectors, while the relatively strong hydrophobicity of the surface of chalcopyrite still can be maintained when the flotation was processed using both the OIMA and collectors