Production of high purity thorium oxide from complex ores leach liquor

Year 2021, Volume: 164 Issue: 164, 1 - 10, 15.04.2021

Ayşe Erdem Haydar Güneş , Çiğdem Kara Hasan Akçay Akan Gülmez Zümrüt Alkan

https://doi.org/10.19111/bulletinofmre.709316

Cited By: 1

Abstract

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

Thanks

This study was supported by the General Directorate of Mineral Research and Exploration within the scope of Scientific Research Projects. Authors would like to thank to Mehmet Ergin from Cytec Inc. Turkey for his advices about the solvents and Ufuk Kibar, Nihal Görmüş and Gökçe Gürtekin from General Directorate of Mineral Research and Exploration for their contributions with SEM-EDS analyses and images.

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