Adsorption–Desorption of La3+, Eu3+, and Y3+ by Mg(OH)2-Pretreated TP207 Resin

The adsorption–desorption behavior of La3+, Eu3+, and Y3+ by Mg(OH)2-pretreated TP207 resin in sulfate solution has been investigated. The effects of the reaction duration, pH value, flow rate, and adsorption mechanism were studied in detail. The results show that the highest adsorption capacity is obtained at solution pH of 4.0. The adsorption affinity of the resin for the different rare-earth ions lies in the order La3+ > Eu3+ > Y3+, while the static equilibrium adsorption capacity is 0.73 mmol g−1, 0.51 mmol g−1, and 0.35 mmol g−1, respectively. The optimum desorption conditions are 1 mol L−1 hydrochloric acid at a flow rate of 4 mL min−1. The desorption liquid enrichment peaks follow the order La3+ > Eu3+ > Y3+, with corresponding enrichment factors of 24, 23, and 20. The adsorption process of TP207 resin is chemisorption, and the coordination mode between Y3+ and resin functional groups is dominated by three donor atoms, but two for La3+ and Eu3+.