The Adsorption of Copper Ions Using Cyclodextrin Cross-Linked Magnetic Chitosan Microsphere

In this experiment, cyclodextrin cross-linked magnetic chitosan（CCMC ）microsphere was prepared, glutaraldehyde was chosen as crosslinker, Cyclodextrin and chitosan was synthezied. To observe the influence factors of adsorption and obtain the optimum condition, the adsorption of copper ions by CCMC was explored under the different pH, initial concentration, temperature, reaction time and so on. The results indicated that CCMC had a high percentage removal of Cu2+, optimum adsorption was observed at pH 5.0. The adsorption rate of Cu2+ on CCMC was quick and the percentage removal reached beyond 90% after 30min, indicating that the adsorption equilibrium could be established within 30 min. The kinetic and thermodynamic properties of CCMC was also explored, under the concentration of Cu2+ of 50mg/L, 100mg/L, 150mg/L, 200mg/L, 300mg/L, 500mg/L on the temperature of 25°C, 35°C, 45°C, 50°C. Freunlich isothermal to Langmuir isothermal was used to fit the data of adsorption capacity of Cu2+, which showed that the adsorption process of Cu2+ was better described by Freunlich isothermal than Langmuir isothermal. As to the kinetic properties, the experimental data of Cu2+ adsorption onto CCMC fitted to the pseudo-first order model and pseudo-second order model, but the adsorption of Cu2+ onto CCMC conformed to pseudo-second order model, the R2 reached above 0.999.