Ayşe ERDEM, Haydar GÜNEŞ, Çiğdem KARA, Hasan AKÇAY, Akan GÜLMEZ, Zümrüt ALKAN

Production of high purity thorium oxide from complex ores leach liquor

This paper investigates a method for separation and purification of thorium from leach liquors containing rare-earth elements (REE). Iron, which causes problems in the stage of thorium extracting, was first removed by using Adogen 464 solvent. Thorium was extracted with 30% D2EHPA-in kerosene with 1/3 organic/aqueous ratio and stoichiometry of the thorium-D2EHPA complex was calculated as 1:2.6 from slope analysis. After the extraction, LREE and HREE were scrubbed from the extracted organic with 0.25 M H₂SO₄ and 6 M HCl, respectively. Thorium oxalate was precipitated by oxalic acid and calcined at 1,050 °C. It was, after calcination, determined that purity of thorium oxide is 99.23%, based on the ICP-OES analysis.

Keywords:

Thorium, Solvent, Extraction, Leach Liquor,

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ISSN: 0026-4563
Yayın Aralığı: Yılda 3 Sayı
Başlangıç: 1950
Yayıncı: Cahit DÖNMEZ

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