In the present study, a simple, economic and environmentally friend method was utilized for the production
of multi-walled carbon nanotubes (MWCNTs) decorated with Mn0.8Zn0.2Fe2O4 nanoparticles, synthesized
via recycling process of Zn–C battery. The chemical composition and structure of the MWCNTs/
Mn0.8Zn0.2Fe2O4 composite were confirmed by X-ray diffraction and Fourier transform infrared measurements.
The morphology as well as the decoration process was characterized using transmission electron
microscopy. The results showed that the MWCNTs are homogeneously decorated with cubic loosely
agglomerated ferrite particles having mean crystallite size of 20 nm. An appropriate decoration mechanism
was suggested and discussed. The hysteresis measurements exhibited reasonable magnetic characteristics
for the obtained composite which facilitate its separation from their dispersed solution using
normal magnet. Surface area measurement indicates relatively large specific surface enhances its use
in adsorption process. The adsorption capacity of the entire composite was investigated using crystal violet
dye. The effect of composite mass, contact time, solution pH and solution temperature on the adsorption
process was investigated. The adsorption process was found to follow a pseudo-second-order model.
The calculated adsorption thermodynamic parameters (DG, DH and DS) suggested the spontaneity of the
thermodynamically favorable adsorption process.