Advancing green flotation: Separation of Cu-Pb minerals through the application of eco-friendly organic double reaction group depressant
Siqi Yang, Xianping Luo, Rufeng Chen, Louyan Shen, Fan Xun, Jiancheng Miao, Xuekun Tang
Abstract
Achieving efficient flotation separation of chalcopyrite and galena while maintaining environmental friendliness poses a challenge. This study utilized the environmentally friendly copolymer acrylic acid-2-acrylamide-2-methylpropanesulfonic acid (AA/AMPS) as a depressant to separate chalcopyrite and galena. Flotation tests revealed a significant reduction in galena recovery when AA/AMPS was employed, with minimal impact observed on chalcopyrite. In artificial mixed ore flotation, AA/AMPS was found to enhance the efficiency of copper and lead separation, surpassing K 2 Cr 2 O 7 . Furthermore, the effectiveness of AA/AMPS in facilitating copper-lead separation has been validated in practical ore flotation. The presence of AA/AMPS inhibited the adsorption of SBX onto galena, as confirmed by zeta potential and contact angle measurements. However, the adsorption on chalcopyrite remained unaffected. Through analyses using Atomic Force Microscope, X-ray photoelectron spectroscopy, and Density Functional Theory, a robust chemical interaction between the reactive groups in AA/AMPS and Pb sites on galena was uncovered, resulting in the formation of a hydrophilic polymer layer. This layer impedes SBX adsorption and reduces galena’s floatability. In contrast, no significant chemical adsorption was observed between AA/AMPS and Cu and Fe sites on chalcopyrite, preserving its SBX affinity. Overall, AA/AMPS shows promise in replacing traditional depressants for Cu-Pb sulfide ore separation, enhancing environmental sustainability.