Adsorption of Ni(II) ion on Ni(II) ion-imprinted magnetic chitosan/poly(vinyl alcohol) composite

• DOI: 10.1007/s00396-015-3626-4
• Publication Date: 2015-06-04T15:23:49Z
• Authors: Liang Zhang; Lvling Zhong; Shuwei Yang; Dongxin Liu; Yang Wang; Shanshan Wang; Xuanli Han; Xiaomin Zhang
• Keywords: Vinyl alcohol; Langmuir adsorption model

Magnetic chitosan/poly(vinyl alcohol)/Ni(II) beads (m-CTS/PVA/Ni(II)s) were prepared by blending CTS, PVA, Ni(II), and Fe3O4. Ni(II)-imprinted m-CTS/PVA beads (Ni(II)-IMCPs) were obtained by eluting Ni(II) ions from the m-CTS/PVA/Ni(II)s. The optimal conditions for preparing Ni(II)-IMCPs are 2.0 % (w/w) for CTS, 1.5 % (w/w) for PVA, 0.8 % (w/w) for Ni (NO3)2, and 2.0 % (w/w) for Fe3O4. The Fourier transform infrared spectroscopy (FT-IR) analysis implies that the coordinating atoms may be N atom of –NH2 in chitosan and O atom of –OH in poly(vinyl alcohol). The X-ray diffraction (XRD) patterns indicate that there are the Fe3O4 characteristic diffraction peaks and the decrease of the crystallinity for CTS. The study on the adsorptive performances of Ni(II)-IMCPs shows that the process of adsorption is good fitted to Langmuir model and the maximum adsorption capacity of Ni(II)-IMCPs for Ni(II) ions is 500.0 mg g−1 (conditions: V = 20 mL, m = 0.050 g, contact time = 6 h, at 25 °C). Kinetic models were used for interpreting data obtained from batch experiments, which show that the whole adsorption processes for Ni(II) ions on Ni(II)-IMCPs are in accordance with pseudo-second-order kinetic equation. The study of repeating and selective adsorption indicates that Ni(II)-IMCPs have good durability and selectivity for Ni(II) ions.