Abstract

High content of gold in near-surface oxide zones above the gold ore deposit could be recovered using cyanidation. However, restricting the use of cyanide in mines has made it difficult to recover gold within the oxide zone. In this study, we investigated an application of the reductive microwave roasting and magnetic separation (RMR-MS) process for the effective gold recovery from ores in a near-surface oxide zone. Ore samples obtained from the near-surface oxide zone in Moisan Gold Mine (Haenam, South Korea) were used in RMR-MS tests for the recovery of iron and gold. The effect of the RMR process on the recovery of iron and gold was evaluated by given various conditions of the microwave irradiation as well as the dosages of reductant and additive. The microwave roasting resulted in a chemical reduction of non-magnetic iron oxide minerals (hematite) to magnetite minerals, such as magnetite and maghemite. This mineral phase change could induce the effective separation of iron minerals from the gangue minerals by magnetic separation process. The increased iron recovery was directly proportional to the gold recovery due to the coexistence of gold with iron minerals. The RMR-MS process could be a promising method for gold recovery from the ores in near-surface oxide zones.

Details

Title
Effective Gold Recovery from Near-Surface Oxide Zone Using Reductive Microwave Roasting and Magnetic Separation
Author
Bong-Ju, Kim 1 ; Cho, Kang Hee 2 ; Sang-Gil, Lee 1 ; Cheon-Young, Park 3 ; Choi, Nag-Choul 2 ; Lee, Soonjae 1   VIAFID ORCID Logo 

1  Department of Earth and Environmental Sciences, Korea University, Anam-ro 145, Sungbuk-gu, Seoul 02841, Korea 
2  Department of Rural Systems Engineering/Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea 
3  Department of Energy and Resource Engineering, Chosun University, Gwangju 61452, Korea 
First page
957
Publication year
2018
Publication date
2018
Publisher
MDPI AG
e-ISSN
20754701
Source type
Scholarly Journal
Language of publication
English
DOI
https://doi.org/10.3390/met8110957
ProQuest document ID
2582834812
Copyright
© 2018 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.