A versatile β-cyclodextrin and N-heterocyclic palladium complex bi-functionalized iron oxide nanoadsorbent for water treatment.

By industrialization, management of water resources is known as one of the most challenging issues for human society due to the presence of various contaminants such as oil, azo dyes, and micropollutants in water. The treatment of wastewaters containing more than one type of pollutants via a single-step process cannot be performed by a simple adsorption process. In this study, by combining the advantages of superparamagnetic iron oxide, carboxymethyl-β-cyclodextrin polymer, and N-heterocyclic palladium complex, a versatile bi-functionalized iron oxide nanoadsorbent [FeO@CM-β-CDP@Tet-Pd] was fabricated for the capture of toxic dyes in wastewater. The structure of nanoadsorbent was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, and vibrating sample magnetometer analysis. Afterward, the catalytic activity of the synthesized nanoadsorbent was examined in the aqueous solution of sodium borohydride as the reducing agent for rhodamine B, methylene blue, 4-nitrophenol, Metanil yellow, and Eosin Y. The UV-vis spectroscopy was used to monitor the catalytic activity of the [FeO@CM-β-CDP@Tet-Pd] in an aqueous medium. The nanoadsorbent was successfully recovered and re-used six times, without remarkable loss in its catalytic activity. These results showed that the combination of iron oxide nanoparticles with carboxymethyl-β-cyclodextrin polymer provides a promising well-performed and easily recyclable nanoadsorbent for dye uptake and wastewater treatment.