Adsorption of ytterbium (III) from aqueous solution by SQD−85 resin
(Department of Applied Chemistry, Zhejiang Gongshang University, Hangzhou 310012, China)
Abstract: Adsorption and desorption behavior of Yb (III) by SQD−85 resin was investigated by various chemical methods and IR spectrometry. The adsorption capacity of SQD−85 resin for Yb (III) was studied as a function of solution pH, initial concentration of Yb(III), temperature and contact time. The optimal pH for the adsorption was 5.50 in the HAc-NaAc system, and the maximum adsorption capacity was estimated to be 347.6 mg/g at 308 K. The isotherms adsorption data fit well with Langmuir model. The adsorption kinetics data are in agreement with pseudo-second-order model. Thermodynamic parameters indicate that Yb (III) adsorption by SQD−85 resin is endothermic and spontaneous in nature. Thomas model is reasonably accurate in predicting experimental column results. The dynamic desorption rate of Yb(III) can increase to 97.3% when the elution agent is 1.0 mol/L HCl. These results suggest that Yb(III) in aqueous solution can be removed and recovered by SQD−85 resin efficiently.
Key words: SQD−85 resin; adsorption; Yb(III); kinetics; thermodynamics; mechanism