The selective adsorption mechanism of calcium ions/pullulan in the flotation separation of chalcopyrite from talc

• Published in: Chemical engineering science 2025-02, Vol.302, p.120819, Article 120819
• Main Authors: Liu, Cheng, Qi, Zhihang, Ren, Liuyi, Yang, Siyuan
• Format: Article
• Language: English
• Subjects: Calcium ion; Chalcopyrite; Flotation separation; Interaction mechanism; Pullulan polysaccharide; Talc
• ISSN: 0009-2509
• DOI: 10.1016/j.ces.2024.120819

Calcium ions bridged the pullulan and talc surface, then achieving the flotation separation of chalcopyrite from talc. [Display omitted] •Pullulan selectively depressed the floatability of talc in the presence of calcium ions.•Separation of chalcopyrite from talc could be achieved with the calcium ions/pullulan reagent scheme.•Pullulan weakly absorbed on chalcopyrite surface but chemically absorbed on the Ca2+ treated talc surface.•A possible interaction model of the calcium ions/pullulan on the minerals surface is proposed. The flotation separation of chalcopyrite from talc by use of pullulan and sodium butyl xanthate (SBX) under calcium ions was investigated in this study. The single mineral flotation shows that SBX collector had a good collecting ability for chalcopyrite while talc had a good natural floatability. The talc flotation was observably depressed while that of chalcopyrite was not affected in the presence of pullulan alone. With the addition of calcium ions. The depression of talc could be achieved with a small amount of pullulan. The artificial chalcopyrite/talc mixture flotation tests reveal that the addition of pullulan could realize the separation of chalcopyrite from talc in the absence and presence of calcium ions, and the dosage of pullulan with calcium ions was lower than that in the absence of calcium ions. Zeta potential measurements suggest pullulan was easily adsorbed onto the calcium ions treated talc surface, and the XPS tests further confirm that calcium ions could selectively adsorb onto the talc surface and increase its activated sites for hydrogen bonding with pullulan molecules. This study is expect to provide a novel polysaccharide depressant for the beneficiation of chalcopyrite from talc.