Synthesis and characterization of robust zero valent iron/mesoporous carbon composites and their applications in arsenic removal. (November 2015)

• Record Type: Journal Article
• Authors: Baikousi, Maria; Georgiou, Yiannis; Daikopoulos, Chris; Bourlinos, Athanasios B.; Filip, Jan; Zbořil, Radek; Deligiannakis, Yiannis; Karakassides, Michael A.
• Is Part Of: Carbon. Volume 93(2015)
• Page Start: 636
• Page End: 647
• Publication Date: 2015-11
• Subjects: Carbon -- Periodicals; Carbone -- Périodiques; Koolstof; Toepassingen; Electronic journals; 546.681
• DOI: 10.1016/j.carbon.2015.05.081
• Languages: English
• ISSNs: 0008-6223

Abstract

Abstract: Nanoscale zero valent iron particles (nZVI) have been developed by in situ reduction of Fe 3+ ions onto a mesoporous type of carbon matrix – Starch-Derived Mesoporous Carbonaceous Material previously reported and marketed commercially as "Starbon". The obtained nZVI/Starbon hybrid material exhibits homogeneous distribution of nZVI (10–20 nm) within the carbon matrix, surface area of 141 m 2 /g and a total iron loading of 1 mmol per gram of the composite, in accordance with transmission electron microscopy (TEM), X-ray diffraction (XRD), N2 adsorption–desorption measurements, Infrared (IR)/Raman spectroscopy and Thermal gravimetric (TG)/Differential Thermal analysis (DTA). Electron Paramagnetic Resonance (EPR) and proton binding measurements show that the nanoparticles have a core–shell structure with iron(III) oxide/hydroxide shell due to partial air-oxidation of nZVI and the composite exhibits four different types of proton binding groups. Most importantly, the nZVI/Starbon hybrid has been tested as absorbent for As(III) removal showing a total removal of 358 μmol (26.8 mg) of As(III) per gram of the composite at pH = 7. We also discuss the principal role of surface OH groups of iron oxide in arsenic uptake and the crucial effect of pH on removal efficiency.