Fluorination of Rare Earth, Thorium and Uranium Oxides and Phosphates from Monazite: A Theoretical Approach

Abstract:

Monazite is a light rare earth phosphate which is difficult to process when using conventional chemical processes. It is considered to be one of the most important commercial sources of thorium and lanthanides. Using conventional chemicals to process monazite have caused severe environmental damage as has been demonstrated in the Baotou region, China. Monazite is found in combination with other minerals in nature such as bastnaesite and xenotime. The conventional techniques and chemicals used for the processing of monazite are expensive. In order to address this issue, South Africa would like to beneficiate monazite as part of its mineral beneficiation strategy. Doing so competitively would require a new cheaper and more environmentally friendlier process. A new method for the processing of monazite is currently being investigated. It is proposed to feed the monazite is fed into a plasma reactor to crack it. Potentially the cracking will allow the monazite to be more reactive and susceptible to react with less harsh chemicals. The plasma treated monazite is reacted with a fluorinating compound such as ammonium bifluoride. Ammonium bifluoride is used rather than fluorine or hydrogen fluoride as it is less dangerous to handle. The fluorinated rare earth mixture can now be separated using various methods.

• Periodical: Advanced Materials Research (Volume 1019)
• Pages: 439-445
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1019.439
• Online since: October 2014
• Authors: Dian Kemp*, Antonie C. Cilliers
• Keywords: Fluoride, Plasma, Rare Earth, Thorium, Zirconium

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