Mechanistic studies of arsenate sorption on lithium/aluminum layered double hydroxide intercalated by chloride

摘要：

Layered double hydroxides (LDH), which consist of positively charged mixed-metal hydroxides layers and interlayer anions, were reported earlier than one and half centuries ago. In this study, Li/Al LDH-Cl was chosen as the sorbent to investigate arsenate sorption behavior. Extended X-ray absorption fine structure (EXAFS) analysis of arsenate sorbed on Li/Al LDH-Cl shows that As (V)-Li and As(V)-Al interatomic distances were 2.61±0.03 and 3.07±0.03A and the coordination number of As (V) Li and As(V)-Al were 1.5±0.3 and 2.5±0.5 atoms, respectively. These interatomic distances indicated that the inner-sphere bidentate mononuclear and bidentate binuclear bonding were the dominant arsenate sorption complexes on the planar surfaces and edges of Li/Al LDH-Cl, respectively. This biphasic arsenate sorption behavior was partially attributable to: (i) two different sorption sites of Li, exposing on planar surfaces, and Al, existing on edges of double hydroxyl layers, and (ii) micropore sorp tion sites within the Li/Al LDH-Cl surfaces.

关键词： Arsenate sorption Li/Al LDH-Cl Extended X-ray absorption fine structure (EXAFS) kinetics temperature should be in alphabetic order

作者: Y. T. Liu T. Y. Chen M. K. Wang P. N. Chiang, P. M. Huang

作者单位: Department of Agricultural Chemistry, National Taiwan University, 106, Taipei, Taiwan, China Department of Engineering and System Science, National Tsing Hua University, Hsinchu, Taiwan, China, Department of Soil Science, University of Saskatchewan, Saskatoon, SK, Canada 57H 4A5

会议类型: 国际会议

会议名称: 第九届痕量元素生物地球化学国际会议(9th International Conference on the Biogeochemistry of Trace Elements)

会议地点: 北京

会议语种:英文

页码: 848-849

在线出版日期: 2007-07-15（万方平台首次上网日期，不代表论文的发表时间）