Chemically modified kaolinite nanolayers for the removal of organic pollutants

Modified kaolinite nanolayers were prepared from two-dimensional (2D) raw kaolin through a combination of calcination, acid leaching, and ultrasonic dispersion. The obtained nanolayers were subjected to effective modification with amino functional groups through grafting with (3-aminopropyl) triethoxysilane (APTES). The resultant materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) combined with energy dispersive X-ray spectroscopy (EDS), scanning transmission electron microscopy (STEM), Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS). The results revealed that the chemically modified materials exhibited increased specific surface area and pore structures, and chemical treatments showed obvious effects on the adsorption performance of kaolin. Owing to the protonation of the amino groups, the organic modified material exhibited excellent adsorption performance for Congo red and efficient regeneration. The chemically modified kaolinite nanolayers show significant potential applications in the fields of adsorption, separation, catalysis, and other environmental remediation.