Mechanism of Cu Ion Targeting Combined with an Organic Depressant To Enhance the Flotation Depression of Pyrite

Langmuir. 2024 Nov 21. doi: 10.1021/acs.langmuir.4c04144. Online ahead of print.

ABSTRACT

In this study, pyrite was used as the research object, and the behavior and mechanism of a copper-ion-enhanced organic depressant in depressing pyrite flotation were studied. Microflotation experiments showed that, after the addition of CuSO₄ and N,N-dimethyldithiocarbamate (N,N-DDS), the floating collection efficiency of pyrite declined from 82.37 to 21.03% at pH 8.5. Infrared spectroscopy studies indicated that the addition of CuSO₄ caused a significant enhancement in the characteristic N,N-DDS peaks on the pyrite surface. X-ray photoelectron spectroscopy (XPS) revealed that, following the addition of CuSO₄ and N,N-DDS, the relative atomic concentration of N 1s considerably enhanced on the surface of pyrite, with N 1s derived from N,N-DDS. Time-of-flight secondary ion mass spectrometry showed that, before and after the addition of CuSO₄, the normalized peak values of CSN^– on the pyrite superficial layer were 0.0116 and 0.0032, respectively. All of the above-mentioned results indicate that the Cu ion promotes the adsorption of N,N-DDS on pyrite and facilitates the formation of complex ((CH₃)₂NCSS)₂Cu. The N and S atoms in -NCS and metal ions formed chemical bonds, which were the primary mechanism of the interaction between N,N-DDS and pyrite. This process reduces the floatability of pyrite and achieves the selective depression of pyrite.

PMID:39572189 | DOI:10.1021/acs.langmuir.4c04144