Synthesis and characterization of magnetic halloysite–chitosan nanocomposites: use in the removal of methylene blue in wastewaters


Türkeş E., Sağ Açıkel Y.

International Journal of Environmental Science and Technology, 2019 (SCI-Expanded) identifier identifier

Abstract

Magnetic halloysite–chitosan (MHNT-CTN) nanocomposites were synthesized by turning magnetic halloysite nanotubes (MHNTs) into nanocomposites using biopolymeric chitosan (CTN). The magnetic properties of pure halloysite nanotubes (HNTs) were achieved using the co-precipitation method, and MHNTs were synthesized. The characterization of the MHNTCTN nanocomposite and the pure states of the components forming the nanocomposite was performed by FTIR, TGA, TEM, and VSM. Methylene blue (MB) adsorption on MHNT-CTN nanocomposites was investigated as a function of medium pH, the mass ratio of the components forming the nanocomposite material, and the initial MB concentration. The optimum conditions for MB adsorption on MHNT-CTN were determined as pH 8.0, in a solution volume of 25 mL, 25 mg MHNTCTN, and the MHNT-to-CTN mass ratio of 2:1. The highest adsorption efciency for MB adsorption on MHNT2-CTN1 was reached at an initial MB concentration of 20 mg/L, and it was found to be 83.9%. The adsorption equilibrium data obtained from the studies on MB adsorption on MHNT-CTN were used to investigate compatibility with the Langmuir, Freundlich, and Redlich–Peterson adsorption models. It was found out that the MB adsorption kinetics was compatible with the pseudosecond-order model.