Synthesis and characterization of β-cyclodextrin coated Fe3O4/carbon nanocomposite for adsorption of tea catechin from aqueous solutions

Abstract

β-cyclodextrin (β-CD) coated Fe₃O₄/carbon nanocomposite materials have been prepared by co-precipitation and impregnation method for adsorption of tea catechin from aqueous solutions. The prepared catalysts have been characterized by X-ray diffraction, FT-IR spectrometer, SEM, TEM, TGA, Pyridine FTIR and VSM analysis. The particle diameter and saturation magnetization value of Fe₃O₄/carbon is found to be 25-50 nm from TEM analysis and 4.4 emu/g from VSM analysis and decreases after coating of β-CD on Fe₃O₄/carbon nanocomposite to 20-35 nm and 1.2 emu/g, respectively. The adsorption behaviors of tea catechin on β-CD coated Fe₃O₄/carbon nanocomposites have been investigated schematically. The experimental adsorption affinity is interpreted with the help of Langmuir and Freundlich adsorption isotherms and the Langmuir model is found to be best suitable for the experimental data. The adsorption reaches the equilibrium within 90 min. and follows 1^st order kinetics. The adsorption process depends on temperature, pH and amount of adsorbate and adsorbent.