Chromate removal as influenced by the structural changes of soil components upon carbonization at different temperatures
2012
Chen, K.Y. | Liu, J.C. | Chiang, P.N. | Wang, S.L. | Kuan, W.H. | Tzou, Y.M. | Deng, Y. | Tseng, K.J. | Chen, C.C. | Wang, M.K.
Surface fire could induce heat transferring into the soil, creating a carbonized environment, which may alter the chemical compositions of soil organic matters (SOM). In the study, a surface soil was carbonized at up to 600 °C with limited air to simulate soils experiencing a surface fire, and Cr(VI) removal on the carbonized soils was investigated. NMR and FTIR analyses demonstrated a remarkable change of SOM structures at 300–400 °C. TGA-MS spectra indicated that (e.g. C₂H₄, CH₃OH and C₃H₈) were the major components in the evolved gases from the pyrolyzed soil. A maximum amount of Cr(VI) removal (ca. 4 mg g⁻¹ soil) occurred for the 200 °C-carbonized soils, attributed mainly to a significant increase of Cr(VI) reduction by 0.1 M KCl extractable organic carbon (EOC) with abundant carboxylic groups. Nonetheless, the formation of aromatic C upon carbonization of the soil at >400 °C may be responsible for Cr(VI) reduction.
显示更多 [+] 显示较少 [-]