Selective Oxidation of Cerium in Rare Earth Solutions, a Comparison of Four Oxidants

  • James McNeiceEmail author
  • Ahmad Ghahreman
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)


Separation of rare earth elements (REE) is often achieved by acid leaching of mineral concentrates followed by subsequent solvent extraction (SX), to purify individual rare earth metals (REM). Cerium, the most abundant REE, is usually the largest component of these ores. Demand for less prevalent REE, such as praseodymium and dysprosium; have led to a market saturation and price collapse of cerium. One method of improving the economics of REE separation is to remove cerium from solution prior to SX. This is accomplished via the oxidation of cerium (III) to cerium (IV), which precipitates as cerium hydroxides. This study probes the efficacy of four oxidants; hydrogen peroxide, sodium hypochlorite, potassium permanganate, and Caro’s Acid with the goal of improving cerium removal whilst minimizing REE and reagent losses. The effect of oxidant type and dosage, pH, cerium concentration, and temperature on the kinetics of the process will be discussed.


Cerium Oxidation Kinetics Rare earths Rare earth elements Permanganate Hypochlorite Peroxide Caro’s acid 



The authors would like to acknowledge the financial support for this study through Kingston Process Metallurgy (KPM) and Ontario Centre of Excellence (OCE).


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Copyright information

© The Minerals, Metals & Materials Society 2018

Authors and Affiliations

  1. 1.The Robert M. Buchan Department of MiningQueen’s UniversityKingstonCanada

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