Empleo de electrodos de pasta de carbono (CPE) para evaluar las interacciones entre un mineral de galena y los reactivos típicos del proceso de flotación
Resumen
Se presenta un análisis para evaluar las interacciones del mineral de galena (PbS) y los reactivos típicos del proceso de flotación, usando electrodos de pasta de carbono (CPE) y técnicas electroquímicas. Se realizaron estudios comparativos de voltametría y variación del potencial de reposo para evaluar las interacciones entre la galena y n-isopropil xantato de sodio (NaIPX), con y sin acondicionamiento previo. Las pruebas con la solución en blanco (sin xantato) y electrodo en blanco (CPE-sin mineral) se utilizaron para analizar la adsorción del xantato y los mecanismos de reacción entre las especies, a diferente pH. El análisis determinó que la adsorción de xantato ocurre a potenciales entre -0.25 y 0.05 V, mientras que la flotación se ve favorecida en potenciales entre –0.05 a 0.05 V, debido a la cercanía entre el potencial de reposo y el potencial de formación de Pb(X)2, S0 o X2. El acondicionamiento previo de la superficie mineral de galena con depresores, limita la cinética del proceso de adsorción de xantato y la formación de especies hidrófobas.
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