In this study, a magnetic adsorbent material was produced,
by environmentally
friendly and inexpensive precursor materials, to clean wastewater
that may result from primary and secondary rare earth metal (REM)
production. Then, the absorption of Nd3+ions from wastewater
was done and this process’s kinetic and isotherm models were
developed. Thus, the removal of Nd3+from wastewater with
magnetic materials was accomplished, and then, this precious metal
was recovered by using different acid media. First, Fe sub-micron
particles were successfully produced by the polyol method. To increase
the stability of Fe-based particles, their surfaces were covered with
an oxide layer, and the average thickness was determined as 16 nm.
The synthesized Fe particles were added into the calcium alginate
beads and then coated with chitosan to increase the pH stability of
the gels. The chemical composition of the gels was determined by Fourier
transform infrared spectroscopy, the thermal properties were determined
by differential scanning calorimetry, and the magnetic properties
were determined by vibrating-sample magnetometer analysis. The magnetic
saturation of the hydrogels was 0.297 emu/g. After the production
of magnetic calcium alginate hydrogels, Nd3+ion removal
from wastewater was done. Wastewater was cleaned with 94.22% efficiency.
The kinetic models of the adsorption study were derived, and isotherm
studies were done. Adsorption reaction fitted different kinetic models
at different time intervals and the Freundlich isotherm model. The
effect of pH, temperature, and solid–liquid ratio on the system
was determined and the thermodynamic constants of the system were
calculated. After the adsorption studies, Nd3+ions were
regenerated in different acid environments and achieved an 87.48%
efficiency value. The removal of Nd3+ions from wastewater
was carried out with high efficiency, the gels obtained as a result
of adsorption were regenerated with high efficiency by using acid
media, and it was predicted that the gels could be reused. This study
is thought to have reference results not only for the removal of REM
from wastewater by magnetic adsorption materials but also for the
adsorption of heavy metals from wastewater.