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Minerals & Metallurgical Processing

, Volume 34, Issue 4, pp 161–169 | Cite as

Recovering rare earths from waste phosphors using froth flotation and selective flocculation

  • M. Yu
  • G. MeiEmail author
  • Y. Li
  • D. Liu
  • Y. Peng
Special Issue on Rare Earths

Abstract

This study explores froth flotation and selective flocculation methods to recycle waste phosphors containing several rare earth elements, namely, yttrium (Y), europium (Eu), cerium (Ce) and terbium (Tb). The effects of the presence or absence of collector and of flocculant and their dosages, as well as the pH, were investigated. Reverse flotation resulted in concentrates with grade of 27.03 percent and recovery rate of 71.36 percent, while flocculation resulted in concentrates with grade of 31.43 percent and recovery rate of 91.28 percent. The flotation and flocculation behaviors were further analyzed by X-ray diffraction analysis, zeta potential measurements, particle size distribution and other methods. The successful separation of rare earth minerals by flotation was attributed to the selective adsorption of the collector onto quartz, making it particularly recoverable by reverse flotation so as to be separated from the valuable materials. The analysis of the particle aggregation process indicated that its better flocculation performance was due to the selective adsorption of flocculants onto the unwanted materials, enlarging the flocculant sizes by forming aggregations and facilitating the separation of rare earth minerals from waste materials based on different settling rates.

Key words

Waste phosphors Selective flocculation Froth flotation Rare earth elements 

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Copyright information

© The Society for Mining, Metallurgy & Exploration 2017

Authors and Affiliations

  1. 1.School of Resources and Environmental EngineeringWuhan University of TechnologyWuhanChina
  2. 2.School of Chemistry and Life ScienceHubei University of EducationWuhanChina
  3. 3.School of Chemical EngineeringUniversity of QueenslandSt. LuciaAustralia

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