N. Malumbazo, M. Ndhlalose and N. J. Wagner LEACHING OF URANIUM FROM COAL USING SAMPLES FROM THE SPRINGBOK FLATS COALFIELD: ACID LEACHING. N. Malumbazo, M. Ndhlalose and N. J. Wagner MSc Project: Council for Geoscience and Wits University 2015 International Pittsburgh Coal Conference

Presentation Outline Introduction Project rationale Aims and Objectives Methodology Results Conclusions Future work Acknowledgments 2015 International Pittsburgh Coal Conference

Introduction and Project Rationale 2015 International Pittsburgh Coal Conference

Introduction South Africa sixth in coal production in world 19 Coalfields in SA 2015 International Pittsburgh Coal Conference

Project Rationale SFC not mined to any degree of economic profit, partly due to the presence of U in the coal. SA’s Department of Mineral Resources Beneficiation Strategy - Disentangle uranium and coal in the Springbok flats coalfield. SA’s Integrated resource plan - Increase energy sources by 2030. Limited research about the amount of uranium that is associated with coal & leaching of uranium from coal. 2015 International Pittsburgh Coal Conference

Integrated resource plan for electricity Now Future 2015 International Pittsburgh Coal Conference

Aim and Objectives Aim: Assess feasibility of extracting U from selected SFC coal samples using acid leaching. Objectives: Obtain 5 freshly drilled SFC borehole cores Determine the coal quality. Quantify U present in coal. Identify the coal samples with high U concentration Acid medium to leaching of U from coal 2015 International Pittsburgh Coal Conference

Methodology 2015 International Pittsburgh Coal Conference

Scope of work 2015 International Pittsburgh Coal Conference Drilling and Storage Splitting ICP-MS Ultimate, Prox and CV Leaching Optimized leaching Ur detection Coal quality 2015 International Pittsburgh Coal Conference

Drilling and Storage 2015 International Pittsburgh Coal Conference

Drilling and Storage 2015 International Pittsburgh Coal Conference Carbonaceous shale Bright coal bands Calcite cleats 2015 International Pittsburgh Coal Conference

Leaching Sulphuric acid leaching Sulphuric acid- Previously successful Effect of pH- varying pH, keeping time intervals and temperature const. Effect of time- vary time, keep pH and temperature constant Effect of temp- vary temp, keep pH and time constant 2015 International Pittsburgh Coal Conference

Leaching experiments Reaction conditions Temperature (0C) pH Time (hours) Temperature variation 25, 45, 65 0.5 8 pH variation 25 0.5, 1, 1.5 Time variation 4, 8, 24

RESULTS AND DISCUSSION 2015 International Pittsburgh Coal Conference

Coal quality results 2015 International Pittsburgh Coal Conference

U detection results U in coal zone world average- 2ppm (Swaine, 1990) 2015 International Pittsburgh Coal Conference

U detection results 2015 International Pittsburgh Coal Conference

U results relative to coal quality 2015 International Pittsburgh Coal Conference

Recap 2015 International Pittsburgh Coal Conference Drilling and Storage Splitting ICP-MS, INAA, XRF Ultimate, Prox and CV Leaching Optimized leaching Ur detection Coal quality 2015 International Pittsburgh Coal Conference

Leaching samples Sample name Borehole U [INAA] U [ICP-MS] 1416 BH5 LCZ 8.93 8.6 1417 11.8 9.8 1421 BH3 161 145.9 1422 15.6 11.3 1429 BH2 86.9 85.9 1436 BH1 64.6 34.1 1437 43.2 13 1438 39.4 19.4 1439 29.3 20.9 1440 11.5 6.2 1443 BH4 33.5 34.4

Leaching Results- Time Effect 2015 International Pittsburgh Coal Conference

Leaching Results- pH effect 2015 International Pittsburgh Coal Conference

Leaching Results- Temperature effect 2015 International Pittsburgh Coal Conference

Conclusions and Future Work 2015 International Pittsburgh Coal Conference

Conclusions: Coal quality BH1 and the UCZ in BH5 ash contents >50% for all the samples; the coal zones are made up almost entirely of carbonaceous shale. BH2 had coal quality that resembles a typical South African bituminous coal and could potentially economically benefit the country. BH3 and BH4 had horizons that are potentially mineable, and could be of use in coal conversion industries. 2015 International Pittsburgh Coal Conference

Conclusions: U content All coal seams studied had U content averages higher than the 2 ppm world average BH3 has the highest U average BH4, the UCZ in BH5 and the LCZ in BH5 all had an average Ur content less than 10 ppm. U in the SFC samples was disseminated throughout the coal and carbonaceous shale. 2015 International Pittsburgh Coal Conference

Conclusions: U detection For all boreholes except BH5, U in the SFC samples was concentrated within the first 1m of the coal zone U in the coal zones was generally restricted to a single layer, usually the highest in the local sequence, except in BH2 and the LCZ in BH5 where U mineralization was seen in multiple locations in the coal zone. U was successfully leached from coal samples into solution. 2015 International Pittsburgh Coal Conference

Future Work Analysis of the acid leached cake samples Leaching using basic medium solutions. Combustion of coal with U. 2015 International Pittsburgh Coal Conference

Acknowledgements Prof N. J. Wagner National Research Foundation:Thuthuka Fund Council for Geoscience 2015 International Pittsburgh Coal Conference

Thank you 2015 International Pittsburgh Coal Conference