Uranium recovery from alkaline leach solutions of low-grade Central Jordan uranium deposits utilizing Lewatit® TP-107

Intensive exploration efforts have confirmed the presence of uranium as a low-grade surficial deposit in the Central Jordan region. According to the Joint Ore Reserve Committee (JORC) compliance resource estimations, approximately 41,000 tons of U₃O₈ with an average grade of 137 ppm are located in this region, presenting challenges for effective uranium mining. This study evaluates the use of Lewatit® TP-107 resin for uranium recovery from the pregnant liquor solution produced by the alkaline leach process employed by the Jordan Uranium Mining Company (JUMCO). Uranium adsorption and desorption were examined through batch processes, considering various parameters such as initial pH, contact time, temperature, adsorbent dosage, and initial uranium concentration. The maximum uranium adsorption capacity of Lewatit® TP-107 was found to be approximately 67 mg of U/g of resin at a temperature of 50 °C. Adsorption isotherms were analyzed using both the Langmuir and Freundlich models. Thermodynamic analysis revealed that the Gibbs free energy change (ΔG°) ranged from 27.58 to - 24.05 kJ/mol, the enthalpy change (ΔH°) was 18.03 kJ/mol, and the entropy change (ΔS°) was 141.23 J/mol·K, indicating a spontaneous endothermic adsorption process. Kinetic analysis showed that the adsorption rate followed a pseudo-second-order model, with a squared correlation coefficient (R²) close to unitary. After five consecutive cycles, the resin maintained an efficiency of approximately 85%, similar to its initial performance, when using NaHCO₃ as the eluting solution.