Mechanism of Disinhibition Activation of Na<sub>2</sub>SO<sub>3</sub> and Cu<sup>2+</sup> in Flotation Recovery of Sphalerite from Cyanide Tailings
Zhengyong Song, Shuming Wen, Zhihao Shen, Yongchao Miao, Songlin Chen, Yuebing Liu, Guang Han
Abstract
Sphalerite is a crucial metal mineral in many gold cyanide leaching residue. The flotation recovery of cyanided sphalerite is challenging. Herein, we present a method to efficiently recover zinc resources from cyanide tailings using Na 2 SO 3 and Cu 2+ for the disinhibition activation flotation of cyanided sphalerite. Microflotation tests of pure minerals and closed-circuit flotation tests of real ore demonstrated that adding Na 2 SO 3 can attenuate the adverse effects of CN – on the floatability of cyanided sphalerite. The flotation recovery of cyanided sphalerite increased through the synergistic effect of Na 2 SO 3 and Cu 2+ . The surface detection results indicated that Na 2 SO 3 induced the desorption of CN – from the surface of the cyanided sphalerite, thereby weakening the shielding effect of the Zn–CN components on the adsorption of collectors on the cyanided sphalerite surfaces. Additionally, after adding Na 2 SO 3 and then Cu 2+, more Cu–S active constituents were produced on the surface of the cyanided sphalerite instead of Cu–CN components, providing more active sites for the adsorption of collectors on the cyanided sphalerite surfaces. Thus, the ideal flotation of cyanided sphalerite was achieved after disinhibition activation by Na 2 SO 3 and Cu 2+ . The current study is expected to serve as a reference for decision-makers when evaluating sustainable management options for cyanide tailings.