Carrier-microencapsulation for suppressing flotability and oxidation of pyrite in copper mineral processing.

Pyrite coexisting with copper sulphide minerals such as chalcopyrite is separated by flotation as tailings and is oxidised in tailings dams, resulting in the formation of acid mine drainage. To suppress both the flotability and the oxidation of pyrite, a carrier micro-encapsulation process has been developed in which an organic carrier combined with Ti is used to form a thin TiO2 layer on the surface of the pyrite. Ground pyrite samples were treated with a Ti-catechol complex solution under various conditions. Bubble pick-up and flotation experiments showed that the characteristics of the pyrite changed from hydrophobic to hydrophilic, even in the presence of xanthate as a flotation collector. Oxidation tests using 0.02 kmol/m3 HNO3 showed that Fe release was suppressed by the treatment due to the formation of a TiO2 coating.
Pyrite coexisting with copper sulphide minerals such as chalcopyrite is separated by flotation as tailings and is oxidised in tailings dams, resulting in the formation of acid mine drainage. To suppress both the flotability and the oxidation of pyrite, a carrier micro-encapsulation process has been developed in which an organic carrier combined with Ti is used to form a thin TiO2 layer on the surface of the pyrite. Ground pyrite samples were treated with a Ti-catechol complex solution under various conditions. Bubble pick-up and flotation experiments showed that the characteristics of the pyrite changed from hydrophobic to hydrophilic, even in the presence of xanthate as a flotation collector. Oxidation tests using 0.02 kmol/m3 HNO3 showed that Fe release was suppressed by the treatment due to the formation of a TiO2 coating.