The South African platinum industry has advanced into an era of predominantly mining and processing Upper Group Two (UG-2) ore to extract Platinum Group Metals (PGMs). Flotation concentrates derived from processing UG-2 ore are typically characterized by high chrome contents (>3 wt.%) which are not amenable to conventional PGM smelters. The net effect of high chrome, inter alia, includes increased smelting energy requirements and the reduction of effective furnace capacity. Various interventions ranging from the redesign and modification of existing physical and pyrometallurgical operations have been introduced and these have yielded no sustainable solutions. In this study, a hydrometallurgical process was investigated as an alternative route to reduce chrome in UG-2 concentrates. The parameters initially considered for investigation were acid concentration, leaching time, temperature and oxygen flowrate while keeping solid to liquid ratio and agitation rate constant. Results showed that oxygen flowrate and an interaction of temperature, time and acid concentration had a positive but minimal effect on Cr extraction. The highest Cr extraction obtained was 7.0%. Further test work entailed exploring the effect of solid to liquid ratio using optimized conditions. The results showed a substantial increase of Cr extraction of up to 37%. This represents 1.33% decrease in chrome content, from 3.63% to 2.30%, in UG-2 concentrate.
| Published in | International Journal of Mineral Processing and Extractive Metallurgy (Volume 6, Issue 3) |
| DOI | 10.11648/j.ijmpem.20210603.12 |
| Page(s) | 41-52 |
| Creative Commons |
This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited. |
| Copyright |
Copyright © The Author(s), 2021. Published by Science Publishing Group |
PGM Smelting, UG-2 Concentrate, Chromite, Leaching
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APA Style
Abel Monele Mokadze, Sehliselo Ndlovu, Alan Shemi, Marek Dworzanowski. (2021). The Reduction of Chrome in UG-2 Flotation Concentrate by Hydrometallurgical Means. International Journal of Mineral Processing and Extractive Metallurgy, 6(3), 41-52. https://doi.org/10.11648/j.ijmpem.20210603.12
ACS Style
Abel Monele Mokadze; Sehliselo Ndlovu; Alan Shemi; Marek Dworzanowski. The Reduction of Chrome in UG-2 Flotation Concentrate by Hydrometallurgical Means. Int. J. Miner. Process. Extr. Metall. 2021, 6(3), 41-52. doi: 10.11648/j.ijmpem.20210603.12
AMA Style
Abel Monele Mokadze, Sehliselo Ndlovu, Alan Shemi, Marek Dworzanowski. The Reduction of Chrome in UG-2 Flotation Concentrate by Hydrometallurgical Means. Int J Miner Process Extr Metall. 2021;6(3):41-52. doi: 10.11648/j.ijmpem.20210603.12
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Download@article{10.11648/j.ijmpem.20210603.12,
author = {Abel Monele Mokadze and Sehliselo Ndlovu and Alan Shemi and Marek Dworzanowski},
title = {The Reduction of Chrome in UG-2 Flotation Concentrate by Hydrometallurgical Means},
journal = {International Journal of Mineral Processing and Extractive Metallurgy},
volume = {6},
number = {3},
pages = {41-52},
doi = {10.11648/j.ijmpem.20210603.12},
url = {https://doi.org/10.11648/j.ijmpem.20210603.12},
eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijmpem.20210603.12},
abstract = {The South African platinum industry has advanced into an era of predominantly mining and processing Upper Group Two (UG-2) ore to extract Platinum Group Metals (PGMs). Flotation concentrates derived from processing UG-2 ore are typically characterized by high chrome contents (>3 wt.%) which are not amenable to conventional PGM smelters. The net effect of high chrome, inter alia, includes increased smelting energy requirements and the reduction of effective furnace capacity. Various interventions ranging from the redesign and modification of existing physical and pyrometallurgical operations have been introduced and these have yielded no sustainable solutions. In this study, a hydrometallurgical process was investigated as an alternative route to reduce chrome in UG-2 concentrates. The parameters initially considered for investigation were acid concentration, leaching time, temperature and oxygen flowrate while keeping solid to liquid ratio and agitation rate constant. Results showed that oxygen flowrate and an interaction of temperature, time and acid concentration had a positive but minimal effect on Cr extraction. The highest Cr extraction obtained was 7.0%. Further test work entailed exploring the effect of solid to liquid ratio using optimized conditions. The results showed a substantial increase of Cr extraction of up to 37%. This represents 1.33% decrease in chrome content, from 3.63% to 2.30%, in UG-2 concentrate.},
year = {2021}
}
TY - JOUR T1 - The Reduction of Chrome in UG-2 Flotation Concentrate by Hydrometallurgical Means AU - Abel Monele Mokadze AU - Sehliselo Ndlovu AU - Alan Shemi AU - Marek Dworzanowski Y1 - 2021/08/04 PY - 2021 N1 - https://doi.org/10.11648/j.ijmpem.20210603.12 DO - 10.11648/j.ijmpem.20210603.12 T2 - International Journal of Mineral Processing and Extractive Metallurgy JF - International Journal of Mineral Processing and Extractive Metallurgy JO - International Journal of Mineral Processing and Extractive Metallurgy SP - 41 EP - 52 PB - Science Publishing Group SN - 2575-1859 UR - https://doi.org/10.11648/j.ijmpem.20210603.12 AB - The South African platinum industry has advanced into an era of predominantly mining and processing Upper Group Two (UG-2) ore to extract Platinum Group Metals (PGMs). Flotation concentrates derived from processing UG-2 ore are typically characterized by high chrome contents (>3 wt.%) which are not amenable to conventional PGM smelters. The net effect of high chrome, inter alia, includes increased smelting energy requirements and the reduction of effective furnace capacity. Various interventions ranging from the redesign and modification of existing physical and pyrometallurgical operations have been introduced and these have yielded no sustainable solutions. In this study, a hydrometallurgical process was investigated as an alternative route to reduce chrome in UG-2 concentrates. The parameters initially considered for investigation were acid concentration, leaching time, temperature and oxygen flowrate while keeping solid to liquid ratio and agitation rate constant. Results showed that oxygen flowrate and an interaction of temperature, time and acid concentration had a positive but minimal effect on Cr extraction. The highest Cr extraction obtained was 7.0%. Further test work entailed exploring the effect of solid to liquid ratio using optimized conditions. The results showed a substantial increase of Cr extraction of up to 37%. This represents 1.33% decrease in chrome content, from 3.63% to 2.30%, in UG-2 concentrate. VL - 6 IS - 3 ER -
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