ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Solvent extraction of uranium and vanadium from carbonate leach solutions of ferruginous siltstone using cetylpyridinium carbonate in kerosene

Mohamed F. Cheira

Nuclear Materials Authority, Cairo, Egypt

E-mail: mf.farid2008@yahoo.com

Received: 9 October 2019  Accepted: 22 January 2020

Abstract:

The leachability of uranium and vanadium ions was conducted from ferruginous siltstone using carbonate ions. The optimum alkaline leaching parameters for dissolving about 92.92% U(VI), and 94.82% V(V) were 70 mg/L Na₂CO₃, 150 mg/L NaHCO₃, 1:3 solid:liquid (S:L) ratio, and 150 rpm stirring rate, for 5 h leaching time at 50 °C. Uranium and vanadium ions were extracted from the carbonate leach liquor using the prepared cetylpyridinium carbonate [(CP)₂CO₃] in kerosene. The maximum extraction of U(VI) was gained using 0.012 M/L (CP)₂CO₃ and 5% (w/v) tridecyl alcohol (TDA) in kerosene from the carbonate leach solution assaying 413 mg/L U(VI) at pH 11 and 3:1 aqueous:organic (A:O) phase. Moreover, the maximum extraction of V(V) was achieved using 0.012 M/L (CP)₂CO₃ and 5% (w/v) TDA in kerosene from the carbonate leach solution containing 336 mg/L V(V) at pH9, and 3:1 A:O phase ratio. Vanadium ions were scrubbed from the uranium-loaded solvent and then it was followed by uranium stripping while vanadium ions were stripped from the vanadium-loaded solvent. McCabe–Thiele diagrams for U(VI) and V(V) extraction and stripping were constructed to determine the theoretical stages of extraction and stripping. Finally, the optimum conditions were applied to gain the sodium diuranate and ammonium vanadate cakes from carbonate leach liquor with the appropriate purities.

Keywords: Carbonate leaching; Uranium; Vanadium; Cetylpyridinium carbonate; Solvent extraction

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-020-01073-w

Chemical Papers 74 (7) 2247–2266 (2020)