Cheng-Lin Pan , Xiang-Xiang Wei , Xu-Gang Zhang , Yong-Wei Xu , Peng-Fei Xu* , Yong-Chun Luo*
https://doi.org/10.1016/j.mineng.2022.107625
In this work, 2-((5-mercapto-1,3,4-thiadiazol-2-yl)thio)acetic acid (MTAA), a stable and eco-friendly organic small-molecule reagent, was introduced as chalcopyrite depressant for selective flotation separation of molybdenite from chalcopyrite. In the flotation experiments of single mineral and artificially mixed mineral, the recovery of chalcopyrite reduces from 90% to 5% in the pH range of 5 to 10 when MTAA (8 mg/L) is added. The results of IR and zeta potential show that there are two tautomers (thione and thiol) in solid MTAA, while in aqueous solution, MTAA is mainly in the form of thiol and reacts with copper ions. The results of XPS and Tof-SIMS measurements indicate that MTAA may react with copper ions to form a quaternary chelate structure via the S and N atoms. The DFT calculation results also show that MTAA is more likely to react with copper ions than iron ions.