Review on surface characteristics and flotation recovery of typical sulfide minerals in cyanide tailings

Cyanide tailings contain substantial amounts of valuable elements such as Cu, Fe, Pb, and Zn, presenting considerable potential for resource utilization. The cyanide leaching of gold ore involves complex physical and chemical interactions that play a key role in the flotation separation of sulfide minerals from cyanide tailings. Firstly, the crystal structure, physico−chemical properties, and flotation behavior of sulfide minerals in the gold ore grinding system are reviewed. Secondly, the mechanism of deep cyanide inhibition at the flotation interface of chalcopyrite, pyrite, galena, and sphalerite in cyanide tailings is discussed. Additionally, the characteristics and practical applications of major decyanation methods used domestically and internationally are summarized. Finally, the process and key factors influencing the flotation recovery of sulfide minerals in industrial applications are reviewed. The type and stability of cyanide at the mineral interface were identified as critical factors influencing the flotation separation efficiency of sulfide minerals. Based on these findings, it is recommended to optimize the physico−chemical properties of sulfide mineral surfaces during grinding, to develop advanced cyanide degradation technologies and reagents, and to improve the selectivity of sulfide mineral flotation. These strategies are essential to maximize the efficient and sustainable utilization of cyanide tailings.