O Mecanismo de Oxidação das Piritas e a Exploração Sustentável dos Recursos Minerais – A Contribuição da Química Computacional

Resumo

The society of low carbon, energy efficient, sustainable, and with competitive economy needs critical raw materials for its development. The mining activity for extracting many future-bearing metals bumps into the challenge of being sustainable, environmentally responsible, and energetically efficient. The fundamental knowledge of many geochemical, environmental, and physical-chemical phenomena is the key to broadening the possible technological solutions looking for sustainable development. A recurring problem in the mining of non-ferrous metals encrusted in sulfide minerals is its natural oxidation process that can potentially hazard the environment. It is called Acid Mine Drainage (AMD) and it is difficult to be mitigated. This is an example where fundamental knowledge of the surface phenomenon is barely known. Herein, the oxidation mechanism of the pyrite, arsenopyrite, and chalcopyrite at their interface with an aqueous solution is discussed. We have emphasized the contributions provided by computer simulations to this important issue combined with the experimental observations.  The message is that the chemical process and the mineral – aqueous solution interfaces are still not completely known, and they are fundamental to the endeavor of sustainable mining.