Preparation and coordination behavior of cellulose beads derivative modified by 1,5-diaminoethyl-3-hydroxy-1,5-diazacycloheptane

Abstract

Cellulose derivative (MPCN) modified by 1,5-diaminoethyl-3-hydroxy-1,5-diazacycloheptane (DADN) was prepared and characterized by scanning electron microscopy and elemental, and infrared analysis. MPCN and its Cu2+, Pb2+ complexes were characterized by thermogravimetric and differential thermal analysis. The coordination adsorption behavior of MPCN with divalent copper and lead ions was determined. The effects of temperature, initial pH value, and the concentration of MPCN ligand to the equilibrium adsorption were discussed. The optimum pH range of the coordination adsorption of MPCN with Cu2+ and Pb2+ is 5–6. The rate constants of the coordination reaction were found. At 323 K, the rate constant is 1.0 × 10−3 and 7.0 × 10−4 s−1 for Cu2+ and Pb2+, respectively. The thermodynamic parameters of the coordination reaction were obtained based on the experiment data of the adsorption isotherms. The coordination reaction was performed spontaneously from the data of ΔG, as follows: −21.65 and −19.41 kJ/mol and ΔS, 87.06 and 67.92 J/mol K for Cu2+ and Pb2+, respectively. The coordination ratio of DADN coordination group immobilized on cellulose beads with either metal ion is about 1 : 2 from the plot of the relation of lgD versus lgL and the capacity of saturation adsorption. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 1278–1285, 1999