Synthesis of homogeneous styrenic pyridine resin (LSL-030-bd) and its application to the separation of uranium and molybdenum

Abstract

This paper synthesized a stytypyridine (LSL-030-bd) resin with small particle size and uniform distribution to recover molybdenum resources leached during neutral in-situ leaching of uranium. The batch experiment results show that the LSL-030-bd ion exchange resin produced had the highest U(VI) adsorption capacity at pH 7.0, reaching 187.20 mg·g⁻¹. At pH 3.0, LSL-030-bd resin adsorbed 180.17 mg·g⁻¹ of Mo(VI). At pH 7.0, the resin exhibited the highest separation coefficient for uranium and molybdenum, with a KD value of 9.08. The resin's adsorption of U(VI) is a spontaneous endothermic process involving monolayer adsorption that combines physical and chemical adsorption. The adsorption of Mo(VI) by the resin is an exothermic process that is not spontaneous. It involves monomolecular layer adsorption with hydrogen bonding as the primary chemical force. By desorbing molybdenum with NH₄SCN, followed by utilizing a mixed solution of NH₄HCO₃ and (NH₄)₂CO₃ to desorb uranium, a step-by-step desorption process may be achieved to separate and purify uranium and molybdenum.