Modified Magnetic Core- Zeolitic Shell Structures Applicable for the Removal of Heavy Metals from Wastewaters

Magnetic core-zeolitic shell structures modified with 3-Glycidyloxypropyl-trimethoxysilane (GPTMS) organic agents prepared by the hydrothermal method. The samples were characterized by X-Ray Diffraction (XRD), Thermo Gravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), and nitrogen adsorption-desorption isotherms (BET). The results of the XRD patterns confirmed the successful growth of aluminosilicate crystals on the surface of the magnetic cores. Furthermore, the SEM images indicated that structures were spherical and the particle size was below 100 nm. The sorption activity of the samples was evaluated by removal of lead and cadmium ions from the wastewaters and according to the results, the final sorbent was enabled to decrease the concentration of cadmium ions selectively. The sorption routes and the effect of the presence of organic agents on the sorption efficiency were mechanistically discussed. The effect of the acidity of the medium on the sorption capacity of the prepared structures was studied and the obtained results were discussed in terms of the chemical structure of the surface.