392-12 Characteristics and Mechanisms of Hexavalent Chromium Removal by Biochar From Sugar Beet Tailing.



Wednesday, October 19, 2011: 4:00 PM
Henry Gonzalez Convention Center, Room 212B, Concourse Level

Xiaoling Dong, Soil and Water Science, University of Florida, Gainesville, FL, Lena Ma, Soil and Water Science, Unversity of Florida, Gainesville, FL, Bin Gao, Agricultural & Biological Engineering, University of Florida, Gainesville, FL and Yuncong Li, Tropical Research and Education Center, University of Florida, Homestead, FL
Removal of Cr(VI) from aqueous solutions using biochar from sugar beet tailing (SBT) was investigated as a function of pH, contact time, and biochar mass via batch experiments. The surface characteristics of SBT biochar before and after Cr(VI) sorption was investigated with scanning electron microscopy equipped with energy dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy. Desorption and X-ray photoelectron spectroscopy studies showed that most of the Cr bound to SBT biochar was Cr(III). These results indicated that the electrostatic attraction of Cr(VI) to positively-charged biochar surface, reduction of Cr(VI) to Cr(III) ion, and complexation between Cr(III) ion and SBT’s function groups were probably responsible for Cr(VI) removal by SBT biochar. An initial solution with a pH of 2.0 was most favorable for Cr(VI) removal. The sorption process can be described by the pseudo-second order equation and Langmuir isotherm. The maximum sorption capacity for Cr(VI) was 123 mg/g under an acidic medium, which was comparable to other low-cost sorbents.
See more from this Division: S11 Soils & Environmental Quality
See more from this Session: Environmental Functions of Biochar: II