| XANES analysis of the mechanisms of arsenic removal in biological iron and manganese treatment unit |
| |
| 作者姓名： | Yoko Fujikawa Daisuke Yoneda Atushi Minami Hiroshi Yashima Toshio Tonokai Sotoji Tani Masami Fukui Tatuhide Hamasaki Masataka Sugahara |
| |
| 作者单位： | [1]Research Reactor Institute, Kyoto University, Osaka, Japan [2]Osaka Sangyo University, Osaka, Japan [3]Groundwater Resources Development Center, Osaka, Japan [4]Toyorosulkl Co., Kyoto, Japan |
| |
| 摘 要： | Biological iron and manganese removal utilizing indigenous iron and manganese oxidizing bacteria （IRB hereafter） in groundwater can also be applied to arsenic removal according to our pilot-scale test. The arsenic removal probably occurred through sorption and complexation of arsenic to iron and manganese oxides formed by enzymic action of IRB. We investigated the chemical properties of iron and manganese oxides in IRB floc and the valence state of arsenic sorbed to the floc to clarify the mechanisms of the arsenic especially As （Ⅲ）] removal. The floc samples were collected from two drinking water plants using IRB （Jyoyo and Yamatokoriyama, Japan）, and our pilot - scale test site where arsenic and iron removal using IRB is under way （Mukoh, Japan）. The Jyoyo and Yamatokoriyama IRB floc samples were subjected to As （Ⅲ） and As（Ⅴ） sorption experiments. The elemental composition of the floc samples was measured. XANES spectra were collected on As, Fe and Mn K-edges at synchrotron radiation facility Spring 8 （Hyogo, Japan）. FT-IR and the X-ray diffraction spectra of the samples were also obtained. The IRB floc contained ca. 35 % Fe, 0.3%-3.5% Mn and 2%-6% P. The samples were highly amorphous and contained ferrihidrites and hydrated iron phosphate. According to XANES analyses of IRB, As associated with IRB was in ＋5 valence state when As （Ⅲ） （or As （Ⅴ）） was added in laboratory sorption test, Fe in ＋3 valence state, and Mn a mixture of＋3 and ＋4 valence states. Small shift was observed in the XANES spectra of IRB on As K-edge as the equilibration time of the sorption experiment was increased. Gradual oxidation of a small amount of As （Ⅲ） associated with IRB or change in arsenic binding with sorption site were the probable mechanism.
|
| 关 键 词： | 砷 地下水 XANES 生物铁 锰 水文化学 |
XANES analysis of the mechanisms of arsenic removal in biological iron and manganese treatment unit |
| |
| Yoko Fujikawa Daisuke Yoneda Atushi Minami Hiroshi Yashima Toshio Tonokai Sotoji Tani Masami Fukui Tatuhide Hamasaki Masataka Sugahara.XANES analysis of the mechanisms of arsenic removal in biological iron and manganese treatment unit[J].Chinese Journal of Geochemistry,2006,25(B08):113-113. |
| |
| Abstract: | |
| |
| Keywords: | arsenic groundwater XANES iron and manganese oxidizing bacteria removal |
| 本文献已被 维普 等数据库收录！ |
|
