| Abstract: | The sorption behavior and mechanism of a novel chelate resin, diglycolamidic acid resin(DAAR), for Sm(Ⅲ) were investigated. The optimal sorption condition of DAAR for Sm(Ⅲ) is pH=6.0 in HAc-NaAc medium. The statically saturated sorption capacity is 190mg/g resin at 298K.The Sm(Ⅲ) adsorbed on DAAR can be ehuted reaching 100% by 0.5～2.0mol/L HCl used as eluant.The resin can be regenerated and reused without apparent decrease of sorption capacity. The apparent sorption rate constant is k29s= 1.96 × 10-5 s-1. The apparent activation energy is 26k J/mol.The sorption behavior of DAAR for Sm(Ⅲ) obeys the Freundlich isotherm. The thermodynamic sorption parameters, enthalpy change △H of DAAR for Sm(Ⅲ) is 16. 9kJ/mol. The molar coordination ratio of the functional group of DAAR to Sm (Ⅲ) is 3. The sorption mechanism of DAAR for Sm(Ⅲ)was examined by using chemical method and IR spectrometry. The coordination bond was formed between oxygen atoms in the functional group of DAAR and Sm(Ⅲ). |
