Giyani Metals is pleased with the results of a solvent extraction phase of its on-going hydrometallurgical testing programme at its K.Hill manganese project in Botswana.

Botswana – The final stage of the programme, electrowinning, is underway and is expected to be completed in the near future. The solvent liquid extraction process is a circuit combining extraction, stripping and precipitation stages.

Giyani Metals says that the purpose of the extraction tests is to purify the leached solutions that were obtained from the acid leaching phase for samples MT10, and MT11. Leaching results for these two samples were announced in May this year.

Purifying the leached solutions from deleterious metal ions results in a highly pure manganese solution that is suitable for electrowinning to produce high-purity electrolytic manganese metal (“HPEMM”), a key component that is needed for the production of batteries for the growing electric vehicle market.

Economically viable project

The manganese recoveries are above 95% and highly suitable for the overall process. In addition, the iron recoveries are within the acceptable limits for the subsequent electrowinning phase. These recoveries can be further fine-tuned in the final circuit design by adjusting key leaching and extraction parameters potentially resulting in higher manganese recoveries and lower iron recoveries.

Robin Birchall, CEO of Giyani Metals commented: “We are very pleased with these extraction results as they represent the most technically challenging steps of the overall SX-EW process. The results bring us one step closer to finalising the hydrometallurgical process route to making our intended end product, EMM.

The key takeaway from these results is that we can achieve economically viable compounded recovery levels at the leaching and extraction phases and produce a manganese solution that is suitable for electrowinning to produce high-purity EMM.”