Estudio cinético de la lixiviación de plata en el sistema S2O32--O2-Cu2+ contenido en residuos minero-metalúrgicos

Abstract

A study on the leaching kinetics of silver involved in the system S 2O32- -O2-Cu2+that is found in the tailings of Dos Carlos in the state of Hidalgo in Mexico. The concentration of [S2O32-] considerably affects the leaching rate obtaining a value of 0.o98 for the order of reaction in the range of concentrations from15.8 to 126.4 gL-1 of S2O 32-, achieving silver recovery of 73%. The effect of temperature and of the addition of copper has been also analyzed. Temperature has a remarkable effect over the overall reaction rate in the range from 15 to 60 °C. Solutions of silver of 97% were obtained at the highest temperature of the study obtaining a value of 43 kJ mol-1 for the activation energy. Copper addition favored the leaching rate of silver, obtaining a reaction order of 0.35 with respect to the concentration of [Cu2+] and reaching 95% of leached silver.