A novel magnetic nanoadsorbent was prepared by the covalent binding of carboxymethyl chitosan (CMC) onto the surface of Fe3O4 magnetic nanoparticles, which was developed using a coprecipitation method. This nanoadsorbent was characterized by transmission electron microscopy (TEM) and X-ray diffraction patterns (XRD), etc. Moreover, the adsorption performance of the nanoadsorbent towards Zn2+ ions was investigated. The results showed that the mean diameter of the magnetic nanoadsorbent was 18 nm and the amount of CMC was about 5%. The nanoadsorbent showed high efficiency for the removal of Zn2+ ions. The adsorption rate was so rapid that the equilibrium was achieved within 2 min. The isotherm adsorption data obeyed the Langmuir model, with a maximum adsorption capacity of 20.4 mg•g−1 and an adsorption equilibrium constant of 0.0314 L•mg−1. The thermodynamic calculation indicated that the adsorption process was exothermic and the enthalpy change was -5.68 kJ•mol−1.

Keywords: Nanoadsorbent   Carboxymethyl chitosan   Fe3O4   Zn2+ion  
Received: 2006-04-04 Accepted: 2006-07-03 Publication Date (Web): 2006-11-06
Corresponding Authors: ZHOU Li-Min Email: minglzh@sohu.com


Cite this article: ZHOU Li-Min;WANG Yi-Ping;LIU Zhi-Rong;HUANG Qun-Wu. Carboxymethyl Chitosan-Fe₃O₄ Nanoparticles : Preparation and Adsorption Behaviors towards Zn²⁺[J]. Acta Phys. -Chim. Sin., 2006,22 (11): 1342-1346.    doi: 10.1016/S1872-1508(06)60067-3