Speaker
Description
This study investigated the interaction between pyrite (FeS₂) mineral surfaces and xanthate and dithiocarbamate (DTC) collectors through a combination of computational Density functional theory (DFT) and microflotation experiments. Although pyrite is commonly regarded as a gangue mineral, its strong flotation tendency under conditions similar to valuable sulphides such as galena, chalcopyrite, and sphalerite often reduces selectivity and metallurgical efficiency. The adsorption of isobutyl xanthate (IBX) and n-Butyl dithiocarbamate (NBDTC) on the pyrite (100) surface at acidic and neutral conditions were performed. It was found that strong chemisorption occurred through Fe and collector S atoms bonding with adsorption energies of –206.8 kJ/mol (SIBX), –245.7 kJ/mol (HIBX), –204.4 kJ/mol (SNBDTC), and –180.4 kJ/mol (HNBDTC). Experimental microflotation tests demonstrated that collector efficiency decreases with increasing pH, as surface oxidation and formation of hydrophilic Fe(OH)₃ films hinder adsorption. At pH = 3, HIBX achieved maximum recovery of 97%, while HNBDTC reached 93%. At pH = 10, recoveries dropped to 83% (SNBX) and 57% (SNBDTC). The combined computational and experimental results confirm that adsorption is thermodynamically more favorable and flotation performance higher under acidic conditions. The study bridges theoretical and experimental insights, providing a mechanistic understanding of collector–pyrite interactions and offering a scientific basis for developing improved strategies to control pyrite depression in sulphides ore flotation.
| Apply for student award at which level: | Honours |
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| Consent on use of personal information: Abstract Submission | Yes, I ACCEPT |