EXAFS study of Zn sorption mechanisms on montmorillonite

被引：72
作者：
Lee, S
Anderson, PR [1 ]
Bunker, GB
Karanfil, C
机构：
[1] IIT, Dept Environm Chem & Engn, Chicago, IL 60616 USA
[2] IIT, Dept Biol Chem & Phys Sci, Chicago, IL 60616 USA
来源：
ENVIRONMENTAL SCIENCE & TECHNOLOGY | 2004年 / 38卷 / 20期
关键词：
D O I：
10.1021/es0350076
中图分类号：
X [环境科学、安全科学];
学科分类号：
08 ; 0830 ;
摘要：
Extended X-ray absorption fine structure (EXAFS) analysis of zinc sorption on montmorillonite showed that different types of surface complexes or surface precipitates were formed depending on the reaction time. With an initial zinc concentration of 10(-3) M at neutral pH, zinc remained octahedrally coordinated with about six oxygen atoms at Zn-O bond distances of 2.02-2.07 Angstrom for up to six months. For samples aged up to 11 days, the Zn-Zn contribution in the second shell suggested formation of multinuclear surface complexes or surface precipitates. For samples aged 20 days and more, Zn-Zn and Zn-Si contributions in the second shell suggested formation of mixed metal coprecipitates such as a Zn phyllosilicate-like phase. Formation of these mixed metal solids probably accounts for the slow continuous sorption reaction at aging times exceeding 20 days. Sequestration of Zn in mixed metal precipitates and the stability of these phases can reduce the concentration, mobility, and toxicity of Zn in soils or sediments.
引用
收藏
页码：5426 / 5432
页数：7
相关论文
共 46 条
[11]   CRYSTAL STRUCTURE OF GAMMA-ZN(OH)2 [J].
CHRISTENSEN, AN .
ACTA CHEMICA SCANDINAVICA, 1969, 23 (06) :2016-+
[12]   Neoformation of Ni phyllosilicate upon Ni uptake on montmorillonite:: A kinetics study by powder and polarized extended X-ray absorption fine structure spectroscopy [J].
Dähn, R ;
Scheidegger, AM ;
Manceau, A ;
Schlegel, ML ;
Baeyens, B ;
Bradbury, MH ;
Morales, M .
GEOCHIMICA ET COSMOCHIMICA ACTA, 2002, 66 (13) :2335-2347
[13]  
EFFENBERGER H, 1981, KRISTALOOGRAPHICA, V156, P223
[14]   Reaction condition effects on nickel sorption mechanisms in illite-water suspensions [J].
Elzinga, EJ ;
Sparks, DL .
SOIL SCIENCE SOCIETY OF AMERICA JOURNAL, 2001, 65 (01) :94-101
[15]   The nature of Zn precipitates formed in the presence of pyrophyllite [J].
Ford, RG ;
Sparks, DL .
ENVIRONMENTAL SCIENCE & TECHNOLOGY, 2000, 34 (12) :2479-2483
[16]   The link between clay mineral weathering and the stabilization of Ni surface precipitates [J].
Ford, RG ;
Scheinost, AC ;
Scheckel, KG ;
Sparks, DL .
ENVIRONMENTAL SCIENCE & TECHNOLOGY, 1999, 33 (18) :3140-3144
[17]   SURFACE-CHEMISTRY OF FERRIHYDRITE .2. KINETICS OF ARSENATE ADSORPTION AND COPRECIPITATION [J].
FULLER, CC ;
DAVIS, JA ;
WAYCHUNAS, GA .
GEOCHIMICA ET COSMOCHIMICA ACTA, 1993, 57 (10) :2271-2282
[18]   CRYSTAL STRUCTURE OF HYDROZINCITE ZN5(OH)6)CO3)2 [J].
GHOSE, S .
ACTA CRYSTALLOGRAPHICA, 1964, 17 (08) :1051-&
[19]  
HELMY AK, 1984, CLAYS CLAY MINER, V42, P444
[20]  
Karanfil C, 2000, AIP CONF PROC, V521, P178, DOI 10.1063/1.1291781
12345