MSc (Eng) Project title A kinetic investigation into the dissolution of pyroxene: A precursor to mineral carbonation of PGM tailings in South Africa
(Supervisors: Dr M Becker, Dr J Broadhurst, Prof D-L Reid) Graduated: 2014
Increasing atmospheric carbon dioxide is currently of considerable concern in terms of global warming. A possible technology that can contribute to the reduction of CO2 emissions is its sequestration by mineral carbonation. This project builds on a preliminary investigative study of the potential to use the large tonnages of PGM tailings produced in South Africa per year for mineral carbonation. Preliminary findings showed that although mineral carbonation of PGM tailings is possible using an ex-situ indirect pH swing method, carbonation efficiencies were low and more favourable for PGM ores rich in olivine and serpentine. These two minerals are well known to show good degrees of conversion to benign carbonate products compared to orthopyroxene for which the available literature on mineral carbonation is sparse, and which is considerably more common in PGM tailings.
The focus of this study is to further investigate the dissolution kinetics of pyroxene relative to olivine, exploringthe effect of pyroxene composition (enstatite, diopside, augite and the pyroxenoid wollastonite), particle size, crystalline irregularities, surface effects as well as temperature and pressure. The results of this study can be used towards the ultimate development of an engineering facility for the mineral carbonation of mine waste.
Peer-reviewed journal publications
Meyer, N.A., Vögeli, J.U., Becker, M., Broadhurst, J.L., Reid, D.L. and Franzidis, J.-P. 2014. Mineral carbonation of PGM mine tailings for CO2 storage in South Africa: A case study. Minerals Engineering, 59: 45-51
Oral conference presentations
Meyer, N., Becker, M., Broadhurst, J.L., Reid, D.L. and Franzidis, J-P. 2014. An investigation into the dissolution of pyroxene minerals. 21st General Meeting of the International Mineralogical Association (IMA 2014), 2-5 September, Johannesburg, South Africa. Also presented at the 32nd annual SAIMM Mineral Processing Conference, 7-8 August, Cape Town
Meyer N. A., Vogeli J., Becker M., Broadhurst J.L. and Reid D. L. 2013. Mineral carbonation of PGM mine tailings for CO2 storage in South Africa: A case study from Lonmin. In: Nasser, R., Santos, R., Cizer, O. & Van Gerven, T. (eds.) 4th International Conference on Accelerated Carbonation for Environmental and Materials Engineering. Leuven, Belgium, 10-13 April 2013, KU Leuven: 505-509. ISBN 978-94-6018-655-4