Abstract
An adsorptive composite was prepared for calcium ions removal. The chemically modified cellulose (EMC) was grafted with the vinyl monomer glycidyl methacrylate using ceric ammonium nitrate as initiator and was further derived with calix[4]arene. The structure of the modified cellulose was characterized by using Fourier transform infrared (FTIR), scanning electron micrographs (SEM), thermogravimetric analysis (TGA), and X-ray diffraction (XRD). Epoxy cellulose was found to contain 3.17 mmol g−1 epoxy groups by the acetone-hydrochloride titration method. The adsorption process of EMC was described by the Langmuir model of adsorption well, and the maximum adsorption capacity of calcium ions reached 104.16 mg g−1. The kinetic studies revealed that the adsorption process followed the pseudo-second-order kinetic model.
Acknowledgements
The authors are grateful for the key scientific and technological project of Henan province (112102310360, 122300410260), the natural science research project of Henan province education department (2011A610005) and the financial support of the foundation of International scientific and technological cooperation of Henan province (124300510012) in China. The authors also thank the anonymous reviewers for their invaluable insight and helpful suggestions.