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In-situ XRD and EDS method study on the oxidation behaviour of Ni-Cu sulphide ore.

ABSTRACT: The oxidation mechanism of sulfides is the key issue during the sulphide-metallurgy process. In this study, the phase transformation and element migration were clearly demonstrated by in-situ laboratory-based X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDS), respectively. The reaction sequence and a four-step oxidation mechanism were proposed and identified. The elemental distribution demonstrated that at a low temperature, the Fe atoms diffused outward and the Ni/Cu atoms migrated toward the inner core, whereas the opposite diffusion processes were observed at a higher temperature. Importantly, the unique visual presentation of the oxidation behaviour provided by the combination of in-situ XRD and EDS might be useful for optimising the process parameters to improve the Ni/Cu extraction efficiency during Ni-Cu sulphide metallurgy.

SUBMITTER: Li G

PROVIDER: S-EPMC5468282 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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In-situ XRD and EDS method study on the oxidation behaviour of Ni-Cu sulphide ore.

Li Guangshi G Cheng Hongwei H Xiong Xiaolu X Lu Xionggang X Xu Cong C Lu Changyuan C Zou Xingli X Xu Qian Q

Scientific reports 20170612 1

The oxidation mechanism of sulfides is the key issue during the sulphide-metallurgy process. In this study, the phase transformation and element migration were clearly demonstrated by in-situ laboratory-based X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDS), respectively. The reaction sequence and a four-step oxidation mechanism were proposed and identified. The elemental distribution demonstrated that at a low temperature, the Fe atoms diffused outward and the Ni/Cu atoms ...[more]

PMID: 28607362

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