Abstract
Tellurium (Te), a critical element for photovoltaic technologies, commonly occurs as a trace constituent in pyrite, which is typically depressed during copper porphyry flotation process and discarded to tailings. Selective flotation of pyrite offers a promising route to enhance Te production within the copper supply chain, although its recovery is often limited by surface oxidation and hydrophilic passivation. This study establishes a mechanistic framework to improve flotation of Te-bearing pyrite from copper sulfide tailings. Micro flotation tests designed using Box–Behnken response surface methodology revealed significant nonlinear and synergistic effects of pH, potassium amyl xanthate (PAX), methyl isobutyl carbinol (MIBC), and activators (NaHS, Na2S, CuSO4). Dual sulfidization with NaHS–Na2S at pH 9.0 yielded optimal performance, with a cubic regression model (R2 = 0.91) accurately capturing reagent interactions. Surface analysis using zeta potential, contact angle, total organic carbon adsorption, and X-ray photoelectron spectroscopy demonstrated that sulfidization suppressed oxidized species and enriched reduced sulfur surface states (S2−/S0), thereby enhancing xanthate chemisorption. Bench-scale flotation with controlled potential activation validated these findings, achieving ∼90% pyrite recovery and ∼82% Te recovery. Overall, this work elucidates the surface-chemical mechanisms controlling Te-bearing pyrite flotation and demonstrates a viable pathway for Te recovery from sulfide tailings.
Recommended Citation
M. Chibesa et al., "Fundamental Surface Chemistry and Mechanistic Insights into the Flotation of Tellurium-bearing Pyrite from Sulfide Tailings," Separation and Purification Technology, vol. 395, article no. 137880, Elsevier, Jul 2026.
The definitive version is available at https://doi.org/10.1016/j.seppur.2026.137880
Department(s)
Mining Engineering
Publication Status
Full Text Access
Keywords and Phrases
Box–Behnken response surface methodology; Contact angle measurement; Critical minerals; Froth flotation; Pyrite; Tailings; Tellurium; X-ray photoelectron spectroscopy; Zeta potential
International Standard Serial Number (ISSN)
1873-3794; 1383-5866
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2026 Elsevier, All rights reserved.
Publication Date
19 Jul 2026
Comments
U.S. Department of Energy, Grant 37989