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Effect of Anions on the Solubility of Rare Earth Element-Bearing Minerals in Acids

  • Kenneth N. Han
Article
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Abstract

The effect of anions such as sulfate, chloride, and nitrate on the solubility of rare earth element-bearing phosphates and fluoro-carbonates has been examined using relevant thermodynamic data. The study has found that these anions have significant influences on the overall dissolution of rare earth elements (REEs) from various sources in the aqueous media. The thermodynamic calculations in this study have indicated that the speciation of REEs with the anions tends to increase the overall solubility of the REE-bearing minerals. However, in some cases, strong precipitation of REEs with some of these anions causes an adverse effect on the solubility of these elements. It has been found that sulfate ion has the most pronounced effect on the solubility compared to nitrate and chloride, in which the latter two acids exhibited almost identical results. The calculated results have indicated that REE-oxide (hydrated) is the easiest compound to dissolve, followed by carbonate, phosphate, fluoride, sulfate, fluoro-carbonate, and oxalate in that order.

Keywords

Speciation Rare earth elements Cut-off-pH Solubility Sulfate precipitation Leaching 

Notes

Acknowledgements

The author would like to express his thanks to Dr. Jim Gebhardt for his valuable comments on the paper and also to Dr. Rina Kim for sharing some of thermodynamic data.

Compliance with Ethical Standards

Conflict of Interest

The author declares that there is no conflict of interest.

References

  1. 1.
    Kim R, Cho HC, Han KN, Kim KH, Mun MW (2016) Optimization of acid leaching of rare-earth elements from Mongolian Apatite-Based Ore. Minerals 6(3):63–78.  https://doi.org/10.3390/min6030063 CrossRefGoogle Scholar
  2. 2.
    Dreisinger DB, Verbaan N, Johnson M (2016) The search minerals direction extraction process for rare earth element recovery. pp. 3-16 In Rare Metal Technology 2016, S. Alam, H. Kim, N.R. Neelameggham, T. Ouchi, & H. Oosterhof (Eds.). The Minerals, Metals & Materials Society. U.S.A.Google Scholar
  3. 3.
    Vijayalakshmi R, Mishra SL, Singh H, Gupta CK (2001) Processing of xenotime concentrate by sulphuric acid digestion and selective thorium precipitation for separation of rare earths. Hydromet 61:75–80CrossRefGoogle Scholar
  4. 4.
    Teixeria da Silva F, Ogawawara T, Barbosa JP, Monheimius AJ (1997) Extraction of yttrium from a Brazilian xenotime concentrate by sulphation and water-leaching. Trans Instn Min. Metall. (Sect C: Mineral Process. Extr. Metall.)* 106:C43–C46Google Scholar
  5. 5.
    Borai EH, Abd El-Ghany MS, Ahmed IM, Hamed MM, Shahr El-Din AM, Aly HF (2016) Modified acidic leaching for selective separation of thorium, phosphate and rare earth concentrates from Egyptian crude monazite. IJMP 149:34–41Google Scholar
  6. 6.
    Kumari A, Panda R, Jha MK, Kumar J, Lee JY (2015) Process development to recover rare earth metals from monazite mineral: a review. Miner Eng 79:102–115CrossRefGoogle Scholar
  7. 7.
    Xie P, Zhang TA, Dreisinger D, Doyle F (2014) A critical review on solvent extraction of rare earths from aqueous solutions. Miner Eng 56:10–28CrossRefGoogle Scholar
  8. 8.
    Jordrens A, Cheng YP, Waters KE (2013) A review of the beneficiation of rare earth element hearing minerals. Miner Eng 41:97–114CrossRefGoogle Scholar
  9. 9.
    Kim E, Osseo-Asare K (2012) Aqueous stability of thorium and rare earth metals in monazite hydrometallurgy:Eh-pH diagrams for the systems Th-, La-, Nd-, (PO4)-(SO4)-H2O at 25°C. Hydrometallurgy, Vol. (113-114), 67-78.Google Scholar
  10. 10.
    Han KN, Kellar JJ, Cross WM, Safarzadeh S (2014) Opportunities and challenges for treatments of rare earth elements. Geosystem Engineering 17(3):178–194CrossRefGoogle Scholar
  11. 11.
    HSC Chemistry 5.11 (2002) Chemical reaction and equilibrium software with extensive thermochemical database. Version 5.0, Outokumpu Research Oy, Piori, Finland.Google Scholar
  12. 12.
    Pourbaix M (1974) Atlas of electrochemical equilibria, National Association of Corrosion Eng., Houston Texas, USA. Pp.644.Google Scholar
  13. 13.
    Firsching FH, Mohammadzadel J (1986) Solubility products of the rare-earth carbonates. Am Chem Soc 31(1):40–42Google Scholar
  14. 14.
    Firsching FH, Brune SN (1991) Solubility products of the trivalent rare-earth phosphates. J Chem Eng Data 36:93–95CrossRefGoogle Scholar
  15. 15.
    Speddin FH, Jaffe GS (1954) Conductances, solubilities and ionization constants of some rare earth sulfates in aqueous solutions at 25°. J. Am. Chem. Soc. 76(3):882–884CrossRefGoogle Scholar
  16. 16.
    Migdiscov A, Williams-Jones AE, Wagner T (2009) An experimental study of the solubility and speciation of the rare earth elements (III) in fluoride- and chloride-bearing aqueous solutions at temperatures up to 300°C. Geochim Cosmochim Acta 73:7087–7109CrossRefGoogle Scholar
  17. 17.
    Chung DY, Kim EH, Lee EH, Yoo JY (1998) Solubility of rare earth oxalate in oxalic and nitric acid media. J Ind Eng Chem 4(4):277–284Google Scholar
  18. 18.
    Gysi AP, Williams-Jones AE (2015) The thermodynamic properties of bastnasite-Ce and parasite-Ce. Chem Geol 392:87–101CrossRefGoogle Scholar
  19. 19.
    Fleischer M (1978) Relative propertions of the lanthanides in minerals of the bastnaesite group. Can Mineral 16:361–363Google Scholar
  20. 20.
    Guastoni A, Kondo D, Nestola F (2010) Bastnasite-Ce and Parisite-Ce from Mt. Malosa, Malawi. Gems Gemology 46(1):42–47CrossRefGoogle Scholar
  21. 21.
    Wagman DD et al. (1982) The NBS tables of chemical thermodynamic properties: selected values for inorganic and C1 and C2 organic substances in SI units. J. Phys. Chem. Ref. Data 11 (suppl. 2) American chemical society and the American institute of physics for the national bureau of standards.Google Scholar
  22. 22.
    Dean JA (ed) (1999) Lange’s handbook of chemistry, 15th edn. McGraw-Hill, NYGoogle Scholar
  23. 23.
    Bian X, Yin S, Luo Y, Wu W (2011) Leaching kinetics of bastnaesite concentrate in HCl solution. Trans Nonferrous Metals Soc China 21:2306–2310CrossRefGoogle Scholar
  24. 24.
    Kul M, Topkaya Y, Karakaya I (2008) Rare earth double sulfates from pre-concentrated bastnasite. Hydromet 93:129–135CrossRefGoogle Scholar
  25. 25.
    Ahmed SH, Helaly OS, Abd El-Ghany MS (2015) Evaluation of rare earth double sulphate precipitation from monazite leach solutions. J. Inorg. Biochem. 5(a):1–8Google Scholar
  26. 26.
    Kim R, Cho HC, Han KN (2014a) Behavior of anions in association with metal ions under hydrometallurgical environments: Part I — OH- effect on various cations. Miner Metall Process 31:34–39Google Scholar
  27. 27.
    Kim R, Cho HC, Han KN (2014b) Behavior of anions in association with metal ions under hydrometallurgical environments: Part II— Effects of Cl-, Br-, I-and CN-. Miner Metall Process 31: 40-47.Google Scholar

Copyright information

© The Society for Mining, Metallurgy & Exploration 2018

Authors and Affiliations

  1. 1.Department of Materials and Metallurgical EngSouth Dakota School of Mines and TechnologyRapid CityUSA

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