Abstract:

A new hydrophilic functional chelating resin(CTS-AMT) with heterocyclic group were synthesized by the graft reaction between 2-amino-5-mercapto-1,3,4-thiadizole(AMT) and macroporous Schiff base chitosan(CTS)chelated bead. The structure of the resin was confirmed by FTIR spectra and elemental analysis. The adsorption property and the selectivity of CTS-AMT and the parent chitosan for Cd2+, Zn2+, Cu2+, Pb2+, Ag+ and Hg2+ were compared. The experimental results show that CTS-AMT has a higher adsorption capacity and a better selectivity than CTS as expected. In the solution of pH=5.0, T=298.15 K, the adsorption of resin on metal ions can be accomplished in about 1.5 h. The static adsorption capacities for Hg2+, Ag+ and Pb2+ are 2.54, 2.31, and 1.71 mmol/g, respectively. It shows that the adsorption isotherms approximately follows Langmuir isotherm equation under the experimental concentrations.

Key words: Cross-linked chitosan, thiadiazole, synthesis, adsorption, Metal ion