Preparation and characterization of a novel magnetic biochar for arsenic removal

• Published in: Bioresource technology Vol. 130; pp. 457 - 462
• Main Authors: Zhang, Ming, Gao, Bin, Varnoosfaderani, Sima, Hebard, Arthur, Yao, Ying, Inyang, Mandu
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.02.2013; Elsevier
• Subjects: Adsorption; Arsenic; Arsenic - isolation & purification; Biochar; Biological and medical sciences; Biomass; Black carbon; Charcoal; Charcoal - chemistry; chemistry; energy-dispersive X-ray analysis; Ferric Compounds; Ferric Compounds - chemistry; Ferromagnetism; Fundamental and applied biological sciences. Psychology; isolation & purification; Kinetics; Magnets; Magnets - chemistry; Micrometers; Nanocomposite; Nanostructure; particle size; Particulate composites; Scanning electron microscopy; Sorption; transmission electron microscopy; Water Pollutants, Chemical; Water Pollutants, Chemical - isolation & purification; X-ray diffraction; X-ray photoelectron spectroscopy; X-rays; γ-Fe2O3; Nanocomposite; Adsorption; Biochar; Black carbon; γ-Fe2O3; Carbonization; Arsenic; γ-Fe; Iron III Oxides; Charcoal; O
• ISSN: 0960-8524; 1873-2976; 1873-2976
• DOI: 10.1016/j.biortech.2012.11.132

[Display omitted] ► A magnetic biochar can be fabricated via pyrolysis of FeCl3 treated biomass. ► Colloidal or nanosized γ-Fe2O3 particles grow within biochar matrix. ► Biochar/γ-Fe2O3 composite has excellent ferromagnetic properties. ► Biochar/γ-Fe2O3 composite has strong sorption ability to As(V). A magnetic biochar based adsorbent with colloidal or nanosized γ-Fe2O3 particles embedded in porous biochar matrix was fabricated via thermal pyrolysis of FeCl3 treated biomass. The synthesized samples were studied systematically by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, selected-area electron diffraction pattern, scanning electron microscopy, energy-dispersive X-ray analysis, superconducting quantum interference device, and batch sorption measurements. The characterization analyses showed that large quantity of γ-Fe2O3 particles with size between hundreds of nanometers and several micrometers tightly grow within the porous biochar matrix. Biochar/γ-Fe2O3 composite exhibited excellent ferromagnetic property with a saturation magnetization of 69.2emu/g. Batch sorption experimental results showed that the composite has strong sorption ability to aqueous arsenic. Because of its excellent ferromagnetic properties, the arsenic-laden biochar/γ-Fe2O3 composite could be easily separated from the solution by a magnet at the end of the sorption experiment.