Characterization of magnetic biochar amended with silicon dioxide prepared at high temperature calcination

• Main Authors: Baig Shams Ali, Lou Zimo, Hayat Malik T., Fu Ruiqi, Liu Yu, Xu Xinhua
• Format: Article
• Language: English
• Published: Sciendo 2016-10-01
• Series: Materials Science-Poland
• Subjects: calcination; magnetic biochar; material composite; saturation magnetization
• Online Access: https://doi.org/10.1515/msp-2016-0112

Calcination is considered to increase the hardness of composite material and prevent its breakage for the effective applications in environmental remediation. In this study, magnetic biochar amended with silicon dioxide was calcined at high temperature under nitrogen environment and characterized using various techniques. X-ray diffraction (XRD) analysis revealed elimination of Fe3O4 peaks under nitrogen calcination and formation of Fe3Si and iron as major constituents of magnetic biochar-SiO2 composite, which demonstrated its superparamagnetic behavior (>80 A2·kg−1) comparable to magnetic biochar. Thermogravimetric analysis (TGA) revealed that both calcined samples generated higher residual mass (>96 %) and demonstrated better thermal stability. The presence of various bands in Fourier transform infrared spectroscopy (FT-IR) was more obvious and the elimination of H–O–H bonding was observed at high temperature calcination. In addition, scanning electron microscopy (SEM) images revealed certain morphological variation among the samples and the presence of more prominent internal and external pores, which then judged the surface area and pore volume of samples. Findings from this study suggests that the selective calcination process could cause useful changes in the material composites and can be effectively employed in environmental remediation measures.