A Study on the Effect of Crystal Habit Modifiers on the Co-precipitation of REE with Gypsum

  • Farzaneh SadriEmail author
  • Zhi Yang
  • Ahmad Ghahreman
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)


Impurity removal is a very important stage of the hydrometallurgical treatment of rare earth elements (REE) processing circuit, which is performed after water leaching of the acid baked REE concentrate. Lime neutralization has a high efficiency in removal of impurities and is the preferred process due to its economic advantage; however, the process has its own problems, such as the production of large volumes of gypsum and co-precipitation of REE with gypsum, i.e. REE loss. This work deals with the effect of several additives (cetryltrimethylammonium bromide (CTAB ), polyvinylsulfonic acid (PVS) and polyacrylic acid (PAA ) on the uptake of REE by gypsum from synthesized acidic solutions. The main purpose of this study is to investigate the changes in the crystalline morphology of gypsum precipitated by the addition of crystal habit modifiers and to determine the crystal changes’ effects on the uptake of REE by gypsum. In this regard, different concentrations (0.2, 2 and 5 g L−1) of above-mentioned additives were studied at room temperature.


Rare earth elements (REE) Gypsum Precipitation CTAB PVS PAA 



The authors would like to acknowledge the financial support for this study through NSERC.


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Copyright information

© The Minerals, Metals & Materials Society 2018

Authors and Affiliations

  1. 1.Department of Mining EngineeringQueen’s UniversityKingstonCanada

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