Ian Wark Research Institute
ARC Special Research Centre
ARC Special Research Centre
Research Area: Physics, chemistry, chemical engineering, materials science
Supervisors: A/Prof Bill
Skinner, A/Prof Daniel
Fornasiero and Dr A Pring (South Australian Museum)
Description: Heterogeneities within bulk mineral phases occur due to stoichiometric variations, the formation of new phases during cooling from melts and oxidation. Such defects can form in the bulk mineral, often concentrating along grain boundaries, altering mineral reactivity and ease of fracture1. High resolution TEM surface spectroscopies, X-ray Tomography, Mössbauer and XRD will be used to examine the behaviour of minerals in process-related environments, linking structural information to mineral reactivity. For the pyrrhotite series of minerals (Fe1-x], a large range of reactivity is exhibited for quite small changes in x. Similar behaviour is suspected for zinc, iron, nickel and silver sulphides, and for some oxides, yet remains unproven2. A special feature of this work will be the accumulation of the surface and bulk composition of key minerals from various sources under different processing conditions, where the fluid phase compositions are also known. This will lead to the formation of a unique resource which will be invaluable in identifying processing behavioural trends3.
Outcome: Bulk mineral heterogeneity reactivity link.
References
1. B. Etschmann, A. Pring, A. Putnis, A. Grguric and A. Studer, A kinetic study of the exsolution of pentlandite from the monosulfide solid solution, American Mineralogist, 89, 39 (2004).
2. W.M. Skinner, H.W. Nesbitt and A.R. Pratt, XPS identification of bulk hole defects and itinerant Fe 3d electrons in natural troilite (FeS), Geochimica et Cosmochimica Acta, 68, 2259 (2004).
3. B.D. Honeymoon, Colloidal culprits in contamination, Nature, 397, 23 (1999).
Funding: All students should apply for an IWRI fully-funded scholarship.
International students should also apply for an International Postgraduate Research Scholarship (IPRS) and a UniSA President’s Scholarship (UPS). To be eligible for UPS, applicants must have a supervisor willing to nominate them for consideration.
Australian students should also apply for an Australian Postgraduate Award (APA) and a UniSA Australian Postgraduate Research Award
(USAAPRA).
International travel and collaboration will be involved in this project and students should be prepared to travel overseas for short periods of focused research.
