Navoi State Mining and Technology University, Navoi, Uzbekistan

I. U. Khalimov, Head of the Department of Rare and Radioactive Metals, Doctor of Technical Sciences
N. М. Karimov, Lecturer of the Department of Rare and Radioactive Metals, e-mail: 92nurkhan92@gmail.com

The relevance of the study is due to the need to increase the efficiency of technologies for processing rare earth elements while reducing costs. Within the framework of the existing methods of processing technological solutions used at the state enterprise “Navoiuran”, a significant part of the costs is associated with the use of expensive reagents for desorption and precipitation. The article presents the results of laboratory studies and production tests of sorption-desorption technology for the extraction of REE oxides from solutions of underground leaching of uranium ores. The REE sorption was carried out with KU-2-8 grade cation exchanger, the dynamic capacity of the resin for REE was 3.2 mg/g. The high capacity of the sorbent is due to preliminary washing with a sulfuric acid solution. Single-stage desorption was studied instead of two-stage desorption with ammonium sulfate (NH₄)₂SO₄ salts, while the REE content in desorbates was 238 mg/l, the degree of desorption increased from 55 to 95%. Ammonium bicarbonate NH₄HCO₃ with a concentration of 10 g/l was used instead of expensive oxalic acid in precipitation processes. With this method, a precipitation rate of 99% was achieved. The proposed technology made it possible to reduce the cost of extracting rare earth elements by 4.4 times during desorption; by 20.2 times during precipitation.

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