Hydrometallurgical preparation of high-grade industrial manganese compound from a low-grade spessartine ore by Cyanex®272 extractant

ABSTRACT

This study highlights a hydrometallurgical method for the purification, extraction, and beneficiation of a multi-elemental leach liquor obtained via reductive leaching of spessartine ore, for the production of high-grade manganese compound. During these treatments, the effect of Cyanex®272 concentrations, pH, aqueous: organic (A/O) was quantified. At optimal conditions (Temperature = 27 ± 2°C, 0.2 mol/L Cyanex®272, pH = 4.5, A/O = 1:1), manganese extraction efficiency was >90%. The stripping of the loaded organic phase by 0.1 mol/L sulphuric acids yielded 95.7% in a single stripping stage. The resulting aqueous solution was appreciably beneficiated to produce manganese sulphate monohydrate (MnSO₄.H₂O: 49–315-9500, melting point = 702.8°C) via precipitation and crystallisation methods. Finally, a flow sheet summarising the analytical treatment steps was provided.

KEYWORDS:

• Spessartine ore
• manganese
• manganese sulphate
• solvent extraction
• Cyanex®272 extractant

Acknowledgments

The authors are grateful to

1. Central Research Laboratories, University of Ilorin, Nigeria for assisting in aqueous metal analyses by AAS.

2. Hydro & Electrometallurgy Department of the CSIR-Institute of Minerals and Materials Technology, Bhubaneswar-751013, India for their benevolence in supplying the CYANEX®272 extractant used in this study.

Disclosure statement

No potential conflict of interest was reported by the author(s).