Scholarlink

<p>The biogeochemical cycles of arsenic (As) and sulfur (S) are intricately linked, yet their interactive mechanisms under anaerobic conditions are not fully understood. This study elucidated these mechanisms through 85-day batch experiments, incubating natural sediments with varying As and S contents (including Low As-sed, As(III)-sed, As(V)-sed, As(III)/S(II)-sed, and As(V)/S(II)-sed) in anaerobic groundwater. Results demonstrated that sulfide (S(II)) fundamentally controlled As release and transformation. In As(III)/S(II)-sed and As(V)/S(II)-sed systems, aqueous As, primarily as As(V), surged to about 6400 and 6000&#xa0;μg/L within 5&#xa0;days before declining to 1400 and 2300&#xa0;μg/L. In contrast, the systems with As(III)-sed and As(V)-sed, aqueous As mainly existed as As(III) and increased gradually to about 4900 and 4500&#xa0;μg/L before 40&#xa0;days, respectively, and then decreased to about 3200 and 3000&#xa0;μg/L, respectively. The initial, rapid mobilization was driven by S(II)-promoted ferric iron (Fe(III)) reduction and competitive adsorption, while subsequent sequestration was attributed to the precipitation of arsenic-sulfide minerals (As<sub>2</sub>S<sub>3</sub>, AsS) and iron-sulfide minerals (FeS<sub>2</sub>, FeS). Microbial community analysis revealed the dominance of anaerobic organisms involved in organic matter decomposition and arsenate reduction, confirming a biological role in As transformation. These findings clarify the dual role of S(II) in controlling the mobility and fixation of As within sulfur-iron-arsenic-rich aquifers, providing a theoretical foundation for managing As contamination in such groundwater systems.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Investigation Into the Role of Sulfides on Arsenic Release and Immobilization in Anaerobic Groundwater: Insights from Batch Experiments

  • 期刊论文

  • 发表日期：

    2026年3月25日

查看全文
  • Sanxi Peng,
  • Ning Wu,
  • Huimei Shan,
  • Jigang Liu,
  • Yunquan Liu

摘要

The biogeochemical cycles of arsenic (As) and sulfur (S) are intricately linked, yet their interactive mechanisms under anaerobic conditions are not fully understood. This study elucidated these mechanisms through 85-day batch experiments, incubating natural sediments with varying As and S contents (including Low As-sed, As(III)-sed, As(V)-sed, As(III)/S(II)-sed, and As(V)/S(II)-sed) in anaerobic groundwater. Results demonstrated that sulfide (S(II)) fundamentally controlled As release and transformation. In As(III)/S(II)-sed and As(V)/S(II)-sed systems, aqueous As, primarily as As(V), surged to about 6400 and 6000 μg/L within 5 days before declining to 1400 and 2300 μg/L. In contrast, the systems with As(III)-sed and As(V)-sed, aqueous As mainly existed as As(III) and increased gradually to about 4900 and 4500 μg/L before 40 days, respectively, and then decreased to about 3200 and 3000 μg/L, respectively. The initial, rapid mobilization was driven by S(II)-promoted ferric iron (Fe(III)) reduction and competitive adsorption, while subsequent sequestration was attributed to the precipitation of arsenic-sulfide minerals (As2S3, AsS) and iron-sulfide minerals (FeS2, FeS). Microbial community analysis revealed the dominance of anaerobic organisms involved in organic matter decomposition and arsenate reduction, confirming a biological role in As transformation. These findings clarify the dual role of S(II) in controlling the mobility and fixation of As within sulfur-iron-arsenic-rich aquifers, providing a theoretical foundation for managing As contamination in such groundwater systems.