Adsorption of Iminodiacetic Acid Resin for Lutetium
摘要
The adsorption behavior and mechanism of a novel chelate resin,iminodiacetic acid resin(IDAAR) for Lu(Ⅲ) were investigated.The statically saturated adsorption capacity is 210.8 mg·g-1 at 298 K in HAc-NaAc medium.The Lu(Ⅲ) adsorbed on IDAAR can be eluted by 0.5 mol·L-1 HCl and the elution percentage reaches 96.5%.The resin can be regenerated and reused without obvious decrease in adsorption capacity.The apparent adsorption rate constant is k298=2.0×10-5 s-1.The adsorption behavior of IDAAR for Lu(Ⅲ) obeys the Freundlich isotherm.The thermodynamic adsorption parameters,enthalpy change ΔH,free energy change ΔG and entropy change ΔS of IDAAR for Lu(Ⅲ) are 13.1 kJ·mol-1,-1.37 kJ·mol-1 and 48.4 J·mol-1·K-1,respectively.The apparent activation energy is Ea=31.3 kJ·mol-1.The molar coordination ratio of the functional group of IDAAR to Lu(Ⅲ) is about 3∶1.The adsorption mechanism of IDAAR for Lu(Ⅲ) was examined by chemical method and IR spectrometry.