Exploring the Sorption Mechanism of Ni(II) on Illite: Batch Sorption, Modelling, EXAFS and Extraction Investigations.
Exploring the Sorption Mechanism of Ni(II) on Illite: Batch Sorption, Modelling, EXAFS and Extraction Investigations.
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探索伊利石上 Ni(II) 的吸附机制：批量吸附、建模、EXAFS 和萃取研究
DOI：
10.1038/s41598-017-09188-z
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发表时间：
2017-08-17
影响因子：
4.6
通讯作者：
Fan Q
中科院分区：
文献类型：
--
作者：
Zhao X;Qiang S;Wu H;Yang Y;Shao D;Fang L;Liang J;Li P;Fan Q
镍（Ni）在伊利石/水界面的吸附机制进行了研究，使用批处理，吸附模型，扩展X射线吸收精细结构（EXAFS），和提取方法。结果表明，Ni（II）在伊利石上的吸附强烈地依赖于pH值、接触时间、温度和Ni（II）初始浓度。当Ni（II）初始浓度较低时，Ni（II）在伊利石上的吸附边出现了离子交换物种α X2 Ni °和内层络合物α SsONi+、α SwONi+和α SwONiOH°物种。当初始Ni（II）浓度增加到1.7 × 10−3 mol/L时，沉淀物包括s-Ni（OH）2和无定形Ni（OH）2的表面诱导沉淀变得更加显著，特别是在中性至碱性条件下。EXAFS分析证实，随着接触时间的增加，Ni-Al层状双氢氧化物（LDH）逐渐形成。在pH 7.0时，由于Al ~（3+）溶出量增加，α-Ni（OH）_2生成初期，随着接触时间的延长，α-Ni（OH）_2转化为更稳定的Ni-Al LDH形式。随着温度的升高，伊利石上的α-Ni（OH）2相转变为Ni-Al LDH相，表明其热力学稳定性低于Ni-Al LDH相。这些结果对于了解Ni（II）污染土壤的地球化学行为，有效修复Ni（II）污染土壤具有重要意义。
The sorption mechanism of nickel (Ni) at the illite/water interface was investigated using batch, sorption modelling, extended X-ray absorption fine structure (EXAFS), and extraction approaches. The results showed that Ni(II) sorption on illite was strongly dependent on pH, contact time, temperature, and initial Ni(II) concentration. At a low initial Ni(II) concentration, the ion exchange species of ≡X2Ni° and the inner-sphere complexes including ≡SsONi+, ≡SwONi+ and ≡SwONiOH° species are observed on the sorption edges of Ni(II) on illite. As the initial Ni(II) concentration increased to 1.7 × 10−3 mol/L, precipitates including surface-induced precipitation of s-Ni(OH)2 and amorphous Ni(OH)2 became more significant, especially under neutral to alkaline conditions. EXAFS analysis confirmed that Ni-Al layered double hydroxide (LDH) can gradually form with an increase in the contact time. At pH 7.0, α-Ni(OH)2 was produced in the initial stage and then transformed to the more stable form of Ni-Al LDH with increasing contact time because of the increased Al3+ dissolution. With an increase in temperatures, α-Ni(OH)2 phase on illite transformed to Ni-Al LDH phase, indicating a lower thermodynamic stability compared to Ni-Al LDH phase. These results are important to understand the geochemical behaviors to effectively remediate soil contaminated with Ni(II).
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pH、离子强度、温度和腐殖质对钠凹凸棒土吸附Ni(II)的影响
影响因子：
15.1
作者：
Fan, Qiaohui;Shao, Dadong;Wang, Xiangke
通讯作者：
Wang, Xiangke
影响因子：
11.4
作者：
Li, Wei;Livi, Kenneth J. T.;Sparks, Donald L.
通讯作者：
Sparks, Donald L.
影响因子：
--
作者：
PANDYA, KI;OGRADY, WE;HOFFMAN, RW
通讯作者：
HOFFMAN, RW
影响因子：
3.6
作者：
Bradbury, MH;Baeyens, B
通讯作者：
Baeyens, B
影响因子：
3.4
作者：
Benedicto, Ana;Degueldre, Claude;Missana, Tiziana
通讯作者：
Missana, Tiziana