Authors: Pedre, Ignacio; Battaglini, Fernando; Gonzalez, Graciela A.
Keywords: Effluents; electrochemical impedance spectroscopy; flotation; mineral samples; xanthate
Xanthate is a widely used reagent in sulfide mineral flotation. A simple and reliable method is presented for the direct monitoring of xanthate in flotation baths and their effluents, as a tool for their reconditioning, and reducing their environmental impact. For this purpose, screen-printed graphite electrodes (SPE) were modified with a polyelectrolyte-surfactant matrix which was able to adsorb the xanthate, whose concentration is determined by electrochemical impedance spectroscopy (EIS) following the change in the electron transfer resistance of ferrocyanide after a pre-oxidation treatment. Linear ranges from 0.25 to 1 mu M and 15 to 100 mu M were determined for effluents and flotation baths, respectively. A mechanism for the electron transfer process is proposed based on Quartz crystal microbalance, IR and cyclic voltammetry studies.
