Role of manganese dioxide in the recovery of oxide–sulphide zinc ore

Publication date: 5 February 2018
Source:Journal of Hazardous Materials, Volume 343
Author(s): Kun Yang, Libo Zhang, Xingcai Zhu, Jinhui Peng, Shiwei Li, Aiyuan Ma, Haoyu Li, Fei Zhu
In this article, the role of MnO2 in the recovery of oxide–sulphide zinc ore discussed. Through adopting various modern analysis techniques (such as X-ray diffraction pattern, X-ray photoelectron spectroscopy, scanning electron microscope, energy dispersive X-ray analysis, and fourier transform infrared spectroscopy), the function and mechanism of MnO2 during the phase transformation process is found out. Thermodynamic mechanisms involved in the phase transformation process with or without addition of manganese dioxide investigated by exploiting the Equilib module of FactSage. What's more, XRD patterns, XPS spectra and SEM-EDAX analyses of zinc calcines verify well the calculations of FactSage. Results reveal that the addition of MnO2 will produce an aggregation of ZnMn2O4, a valuable energy material, while roasting on its own, results in generating undesirable Zn2SiO4, the oxidation degree being relatively low. Moreover, XRD pattern of zinc calcine and FT-IR spectrum of yellow product collected in the calcination process prove that the sulphur-fixing value of the additive MnO2, which can promote transforming to the elemental sulphur. The volatile S can be collected through a simple guiding device. In this process, the emission of SO2 effectively avoids, thus MnO2 deems as a potential additive in the recovery of oxide–sulphide zinc ore.

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