Adsorption of Pb(II) Using Magnetic Titanate Nanotubes Prepared via Two-Step Hydrothermal Method

作者：Zhang Lei; Wang Xin; Chen Huan; Jiang Fang^*

来源：Clean-Soil Air Water, 2014, 42(7): 947-955.

DOI：10.1002/clen.201300582

• Adsorption-desorption-regeneration
• CoFe2O4 nanoparticles
• Cubic magneto-crystalline anisotropy
• Heavy metal pollution
• Magnetic separation

Magnetic titanate nanotubes (MTNTs) have been prepared by a two-step hydrothermal method and used as adsorbents for the removal of Pb(II) from aqueous solution. The MTNTs are characterized by N-2 adsorption-desorption analysis, transmission electron microscopy, powder X-ray diffraction, vibrating sample magnetometer, zeta potentials analysis, X-ray photoelectron spectra (XPS), and Fourier transform infrared (FT-IR) spectroscopy. The results indicate that CoFe2O4 is formed in the hydrothermal process and implanted into the entangled network of nanotubes. The saturation magnetization of MTNTs is 9.20 emug(-1), which makes MTNTs can be readily recovered in an external magnetic field. The adsorption of Pb(II) over MTNTs is very fast and follows the pseudo-second- order kinetic model. Additionally, Pb(II) adsorption is strongly pH dependent and the maximum adsorption capacity of MTNTs for Pb(II) reaches 442.5mgg(-1) at pH 5.0. FT-IR and XPS analysis suggest that the adsorption mechanism of MTNTs is ionic exchange between Pb(II) and Na+/H+ in the interlayer of nanotubes. Furthermore, Pb(II)-loaded MTNTs can be regenerated by saturated EDTA-2Na solution at pH 2.5 and the adsorbents can be used repeatedly.

• 出版日期2014-7
• 单位南京理工大学