The ion-adsorption rare earth tailings have become a serious environmental pollution in Southern
China, yet the potential of their economical value has not been fully exploited. In this work, the
chemical and mineral compositions of the ion-adsorption rare earth tailings were characterized
by Mineral Liberation Analyze (MLA) and XRF. The results show that 91.98 wt% of the tailings are
composed of kaolinite and quartz, latter of which was removed by the sieving method. The other
minor minerals contain feldspar, biotite, muscovite, titanomagnetite and limonite. Amongst these,
the iron-bearing minerals are mostly found in the titanomagnetite and limonite which can be
mostly removed by using a periodic high-gradient magnetic separator with a magnetic induction
of 0.6 Tesla. The Fe2O3 content of the tailings changed from 2.11 wt% to 1.06 wt% after the sorting
process, which met the Chinese national standard of TC-3 grade raw materials for ceramic industry
applications. The Fe2O3 content in kaolinite was further decreased after Na2S2O4 treatment.
References
[1]
Su, W. (2009) Economic and Policy Analysis of China’s Rare Earth Industry. China Financial and Economic Publishing House, Beijing. (In Chinese)
[2]
Chen, Z.H. (2011) Global Rare Earth Resources and Scenarios of Future Rare Earth Industry. Journal of Rare Earths, 29, 1-6.
[3]
Wübbeke, J. (2013) Rare Earth Elements in China: Policies and Narratives of Reinventing an Industry. Resources Policy, 38, 384-394. http://dx.doi.org/10.1016/j.resourpol.2013.05.005
Guo, W. (2012) The Rare Earth Development Can No Longer Overdraw Ecological Cost. China Environment News, China Environmental Press, Beijing.
[6]
Sylvester, P. (2012) Use of the Mineral Liberation Analyzer (MLA) for Mineralogical Studies of Sediments and Sedimentary Rocks. Mineralogical Association of Canada Short Course Series, 42, 1-16.
[7]
Chen, L. (2011) Effect of Magnetic Field Orientation on High Gradient Magnetic Separation Performance. Minerals Engineering, 24, 88-90. http://dx.doi.org/10.1016/j.mineng.2010.09.019
[8]
Svoboda, J. and Fujita, T. (2003) Recent Developments in Magnetic Methods of material Separation. Minerals Engineering, 16, 785-792. http://dx.doi.org/10.1016/S0892-6875(03)00212-7
[9]
Zegeye, A., Yahaya, S., Fialips, C.I., White, M.L., Gray, N.D. and Manning, D.A.C. (2013) Refinement of Industrial Kaolin by Microbial Removal of Iron-Bearing Impurities. Applied Clay Science, 86, 47-53.
http://dx.doi.org/10.1016/j.clay.2013.08.041
[10]
Pham, A.L.T., Doyle, F.M. and Sedlak, D.L. (2012) Kinetics and Efficiency of H2O2 Activation by Iron-Containing Minerals and Aquifer Materials. Water Research, 46, 6454-6462. http://dx.doi.org/10.1016/j.watres.2012.09.020
[11]
Santos, E., Scorzelli, R.B., Bertolino, L.C., Alves, O.C. and Munayco, P. (2012) Characterization of Kaolin from the Capim River Region—Brazil. Applied Clay Science, 55, 164-167. http://dx.doi.org/10.1016/j.clay.2011.11.009
[12]
Chandrasekhar, S. and Ramaswamy, S. (2007) Investigation on a Gray Kaolin from South East India. Applied Clay Science, 37, 32-46. http://dx.doi.org/10.1016/j.clay.2006.11.007
[13]
Xia, G., Lu, M., Su, X. and Zhao, X. (2012) Iron Removal from Kaolin Using Thiourea Assisted by Ultrasonic Wave. Ultrasonics Sonochemistry, 19, 38-42. http://dx.doi.org/10.1016/j.ultsonch.2011.05.008
