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Author(s): |
Shuai Wang, College of Chemistry and Chemical Engineering，Central South University，Changsha 410083，China
Yan-na Wang, College of Chemistry and Chemical Engineering，Central South University，Changsha 410083，China
hong Zhong, College of Chemistry and Chemical Engineering，Central South University，Changsha 410083，China
Liu-yin Xia, College of Chemistry and Chemical Engineering，Central South University，Changsha 410083，China
Zhan-fang Cao, College of Chemistry and Chemical Engineering，Central South University，Changsha 410083，China
Guang-yi Liu, College of Chemistry and Chemical Engineering，Central South University，Changsha 410083，China |
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Abstract: |
A novel polystyrene-modified alkoxycarbonyl thiourea chelating resin (PSATU) was prepared by the reaction of chloromethylated crosslinking polystyrene with diethylenetriamine and then oxydiethane- 2,1-diyl dicarbonisothiocyanatidate successively. PSATU was characterized by FT-IR, and characteristic peaks of bonds such as C=O, C-O-C, C=S, N-H and N-C-N appear in FT-IR spectrum, which justifies that PSATU contains the functional groups of amidocyanogen, alkoxycarbonyl and thioureido. The adsorption performance of PSATU for Ag(?) was studied by batch test. The adsorption capacity of PSATU for Ag(?) reached 4.48mmol·g-1, when the adsorption conditions are as follows: initial concentration of Ag(?) 0.1 mol/L, concentration of HNO3 1.0 mol/L, contact time 20h and temperature 30℃. The adsorption kinetics was well fit Boyd’s diffusion equation of liquid film, and the adsorption isotherm was well fit Langmuir model. The positive value of adsorption enthalpy ΔH and the negative values of Gibbs free energy change ΔG are indicative of an endothermic and spontaneous process. Comparing with FT-IR spectrum of PSATU, characteristic peaks of C=O, C=S and N-H bonds changed obviously after adsorption, indicating that the corresponding functional groups coordinate with Ag during the adsorption process.
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