Electrochemical assessment accounting for the interaction of chalcopyrite/xanthate system Article uri icon

abstract

  • In the current work cyclic voltammetry, capacitance associated to double-layer and Electrochemical Impedance studies on chalcopyrite surfaces in absence and occurrence of Na-isopropyl xanthate at highly concentrated medium in an extensive range of polarization potentials are examined. The voltammetric response of the chalcopyrite surface displays a passivating effect with the addition of xanthate due to its adsorption, which also impedes the transport of oxidized species Fe2 and Cu2 outwards the mineral matrix. A large surface amendment of the chalcopyrite interface at highly thiocollector concentration solutions also becomes evident by analyzing the capacitance-potential curves for different xanthate concentration. Potential Zero Charge (PZC) measurement of the system is equal to 0.2 V vs. SCE and it matches with the adsorption and oxidation potential of xanthate (X-) on the chalcopyrite sample. In addition, impedance spectra being acquired at the passivating region, denotes a pseudocapacitive effect of the system, consistent with the xanthate adsorption and blocking species at the interface. Finally, impedance spectra present three time constants attributed to the oxidative process of chalcopyrite and X- and the formation of covellite and cuprous xanthate on the surface of the mineral, which are in agreement with the voltammetric response obtained for the system. © 2015 The Authors.
  • In the current work cyclic voltammetry, capacitance associated to double-layer and Electrochemical Impedance studies on chalcopyrite surfaces in absence and occurrence of Na-isopropyl xanthate at highly concentrated medium in an extensive range of polarization potentials are examined. The voltammetric response of the chalcopyrite surface displays a passivating effect with the addition of xanthate due to its adsorption, which also impedes the transport of oxidized species Fe2%2b and Cu2%2b outwards the mineral matrix. A large surface amendment of the chalcopyrite interface at highly thiocollector concentration solutions also becomes evident by analyzing the capacitance-potential curves for different xanthate concentration. Potential Zero Charge (PZC) measurement of the system is equal to 0.2 V vs. SCE and it matches with the adsorption and oxidation potential of xanthate (X-) on the chalcopyrite sample. In addition, impedance spectra being acquired at the passivating region, denotes a pseudocapacitive effect of the system, consistent with the xanthate adsorption and blocking species at the interface. Finally, impedance spectra present three time constants attributed to the oxidative process of chalcopyrite and X- and the formation of covellite and cuprous xanthate on the surface of the mineral, which are in agreement with the voltammetric response obtained for the system. © 2015 The Authors.

publication date

  • 2015-01-01