Chemical Engineering Journal, Vol.256, 347-355, 2014
Arsenite remediation by an amine-rich graphitic carbon nitride synthesized by a novel low-temperature method
A novel graphitic carbon nitride (GCN) material has been synthesized through a low-temperature solvolysis of sodium cyanide in formamide. The structure and morphology of the so-obtained GCN solid were studied by X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman/Infrared (IR) spectroscopy and thermal gravimetric analysis (TGA). GCN is characterized by a compacted layered structure bearing a high content of pendant amine groups (1.4 mmol g(-1.)). Electron Paramagnetic Resonance spectroscopy reveals that the pendant amine groups are readily accessible by extrinsic metal cations. Moreover, GCN has a considerable electron-donating capacity to adsorbed electron accepting ions such as Cu2+. GCN shows an appreciable As(III) uptake capacity of 39.7 mg g(-1). Based on theoretical Surface Complexation Model we provide a consistent interfacial/structural picture that describes quantitatively observed phenomena. (C) 2014 Elsevier B.V. All rights reserved.
Keywords:Carbon nitride;Low-temperature solvolysis;Arsenite remediation;Surface Complexation Modeling;FITEQL;EPR