Contradictory tendency of As(V) releasing from Fe-As complexes: Influence of organic and inorganic anions

文献类型： 外文期刊

第一作者： Yang, Zhonglan

作者： Yang, Zhonglan;Zhang, Nan;Su, Shiming;Wang, Yanan;Zhang, Yang;Wu, Cuixia;Zeng, Xibai;Yang, Zhonglan;Sun, Benhua

作者机构：

关键词： Fe-As complex stability; Arsenic pollution; Mineral aging time; Arsenic-releasing tendency; Iron-oxide dissolution

期刊名称：CHEMOSPHERE （ 影响因子：8.943； 五年影响因子：8.52 ）

ISSN： 0045-6535

年卷期： 2022 年 286 卷

页码：

收录情况： SCI

摘要： The strong ability of ferrihydrite and its aged minerals for fixing arsenate is a key factor in remediating arsenatepolluted environments. It is therefore crucial to clarify the stability of Fe-As complexes and the release conditions for As(V). The As(V) release amount was evaluated and compared in the presence of six representative anions, namely, phosphate, silicate, sulfate, inositol hexaphosphate, citrate, and oxalate. It was found that the As (V) release amount changed with the aging time of ferrihydrite and that this tendency generally followed two rules. These are, longer aging time leads to lower As(V) release (Rule 1), and longer aging time leads to higher As (V) release (Rule 2). Whether Rule 1 or Rule 2 dominated As release depended on the number of surface groups, size of competing anions, and contribution of As(V) re-adsorption. Characterization results using X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) provided evidence for the predicted mechanisms of As(V) release under various circumstances. In this work, it was demonstrated that when inorganic anions such as sulfate and silicate are present, ferrihydrite with longer aging time led to decreased As(V) release. When organic anions are present, ferrihydrite with less aging time results in reduced As(V) leaching. For anions such as phosphate, the As(V) release amount in relation to the ferrihydrite aging time depends on the concentration of phosphate ions. Nevertheless, the ligand concentration and As(V) loading rate on ferrihydrite should be simultaneously considered for the rule governing As(V) releasing.

分类号：

  • 相关文献
作者其他论文 更多>>

微信小程序