Electrochemistry of Pentlandite in the Absence and Presence of Sodium Sulfide
Jie Peng, Qiming Feng, Leming Ou, Guofan Zhang, Yiping Lu and Kun Liu* Author for corresponding; e-mail address: kliu@csu.edu.cn
Volume: Vol.39 No.2 (APRIL 2012)
Research Article
DOI:
Received: 21 October 2010, Revised: -, Accepted: 3 July 2011, Published: -
Citation: Peng J., Feng Q., Ou L., Zhang G., Lu Y. and Liu K., Electrochemistry of Pentlandite in the Absence and Presence of Sodium Sulfide , Chiang Mai Journal of Science, 2012; 39(2): 336-345.
Abstract
The collectorless flotation contains self-induced flotation and sodium sulfide-induced flotation. In this paper, we studied the electrochemical performance of pentlandite in both circumstance. In moderate oxidation conditions (viz.0mV < Eh < 500mVvs.SHE), pentlandite was oxidized spontaneously with the main oxidation product of S on the surface, and the highest amount of the S on the surface was oxidized to sulfate which resulted in the hydrophilic surface. Sodium sulfide would increase the hydrophobicity of pentlandite by forming more S on the mineral surface. The extra S might come from the oxidation of hydrogen sulfide ions by the ferric ions which dissolved from the mineral during the oxidation process. These results show that the collectorless flotation of pentlandite would be achieved in the presence of sodium sulfide with the Eh of 300-500 mV.