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Journal of the Southern African Institute of Mining and Metallurgy

On-line version ISSN 2411-9717
Print version ISSN 0038-223X

J. S. Afr. Inst. Min. Metall. vol.108 n.1 Johannesburg Jan. 2008

 

TRANSACTION PAPER

 

Influence of surface effects on the electrostatic separation of zircon and rutile

 

 

J.A. Venter; M.K.G. Vermaak; J.G. Bruwer

Department of Materials Science and Metallurgical Engineering, University of Pretoria

 

 


SYNOPSIS

Electrostatic separation is employed in the concentration of zircon and rutile. The zircon concentrate undergoes an acid treatment to remove impurities from the surface of both the zircon and rutile. The purpose of the acid treatment is to increase the difference in the resistivities of the two minerals, thus ensuring the best possible electrostatic separation efficiencies. Previous test work suggested that these impurities are not removed, but only modified; the surface modification seemed more prevalent in the case of the rutile. The resistivity of the rutile changes with pH and thus the electrostatic separation of the rutile is influenced. X-ray photoelectron spectroscopy (XPS) indicates that there is an increase in the OH and adsorbed H2O concentrations on the rutile surface. XPS also showed significant differential charging on the rutile surface, which indicates that the species on the rutile surface have different resistivities. The zircon particles from the conducting and nonconducting streams have similar resistivities and no major differences in their surface species. Zircon losses during the final electrostatic separation appear not to be due to surface effects, but due to shielding of particles during the separation.


 

 

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References

BRUWER, J.G., VERMAAK, M.K.G., and VENTER, J.A. Zircon surface characterization, The Journal of the Southern African Institute of Mining and Metallurgy, 2007, vol. 104, no. 4, pp. 237-239.         [ Links ]

CHASTAIN, J. (ed.), Handbook of X-ray photoelectron spectroscopy, Perkin-Elmer Corporation, Physical Electronics Division, Eden Prairie, Minnesota, USA, 1992, pp. 40-41.         [ Links ]

DIEBOLD, U. The surface science of titanium dioxide, Surface Science Reports, 2003, vol. 48, pp. 53-229.         [ Links ]

GERSON, A. Zircon surface coatings, ACeSSS, University of South Australia. 2006        [ Links ]

JENSEN, H., SOLOVIEV, A., LI, Z., and SØGAARD, E.G. XPS and FTIR investigation of the surface properties of different prepared titania nano-powders, Applied Surface Science, 2005, vol. 246, pp. 239-249.         [ Links ]

KELLY, E.G. and SPOTTISWOOD, D.J. The theory of electrostatic separation: A review part I. Fundamentals, Minerals Engineering, 1989a, vol. 2, no.1, pp. 33-46.         [ Links ]

KELLY, E.G. AND SPOTTISWOOD, D.J. The theory of electrostatic separation: A review part III. The separation of particles, Minerals Engineering, 1989b, vol. 2, no. 2, pp. 337-349.         [ Links ]

MAO, M., FORNASIERO, D., RALSTON, J., SMART, R., ST. C., and SOBIERAJ, S. Electrochemistry of the zircon-water interface, Colloids and Surfaces A: Physicochemical and Engineering Aspects, 1994, vol. 84, pp. 37-49.         [ Links ]

VENTER, J.A. and VERMAAK, M.K.G. The influence of pH on the electrostatic separation of rutile and zircon, XXIII International Mineral Processing Congress, Istanbul, 2006, pp. 304-309.         [ Links ]

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