Effect of electrochemical interactions among sulphide minerals and grinding medium on the flotation of sphalerite and galena

Abstract

The effect of galvanic interactions among sulphide minerals such as chalcopyrite, galena and sphalerite in the presence and absence of a hyper steel ball material on the flotation recovery of sphalerite and galena has been studied. X-ray photoelectron spectroscopy (ESCA) studies were carried out to identify the reaction products on the sulphide minerals after different types of galvanic interactions. Although prior galvanic contact with a noble mineral such as chalcopyrite did not significantly affect the floatabilities of sphalerite and galena, such an effect was found to be significant in the additional presence of a hyper steel ball material as well as oxygen. Surface analysis studies revealed the presence of copper and lead ions on the sphalerite sample which was in prior contact with chalcopyrite and/or galena both in the presence and absence of the ball material. Also, copper was observed on the galena surface which was previously contacted with chalcopyrite in the presence and absence of the grinding medium. The intensity of copper peak on both the sphalerite and galena mineral surfaces was found to be dependent on the nature of mineral-mineral contacts. Probable electrochemical reaction mechanisms are discussed.