Wang Zongwu, Liu Wei, Sun Xiaoyan, Zhang Qing, Ji Jiapu, Yan Yimeng, Sun Jianhui
Department of Environment Engineering, Yellow River Conservancy Technical Institute, Kaifeng Engineering Research Center for Municipal Wastewater Treatment, Kaifeng 475004, China.
Product Quality Inspection and Testing Center of Kaifeng, Kaifeng 475004, China.
Molecules. 2025 Mar 21;30(7):1406. doi: 10.3390/molecules30071406.
Mercury contamination in groundwater seriously affects human health and ecosystem security. The remediation of Hg-contaminated groundwater remains a challenging task. The applicability of an as-synthesized supramolecular polymer (SP) for low-concentration mercury in a high-salinity groundwater matrix has been verified through a batch process and column test. The remediation of mercury-contaminated groundwater, particularly in complex high-salinity environments, represents a significant and enduring challenge in environmental science. The batch test study demonstrated that the SP can efficiently adsorb Hg from groundwater with superior selectivity and a high uptake capacity (up to 926.1 ± 165.3 mg g). Increasing the pH and dissolved organic matter (DOM) and reducing the ionic strength can facilitate Hg adsorption; the coexistence of heavy metal ions slightly weakens the removal. In terms of its performance as a permeable reactive barrier, the SP can intercept Hg in flowing groundwater with a capacity of up to 3187 mg g. A low influent mercury concentration, low pore velocity, and high SP dosage can effectively extend the breakthrough time in column tests. Additionally, the Yan model ( = 0.960-0.989) can accurately depict the whole dynamic interception process (150 PVs) of SPs in a fixed column, and the Adams-Bohart model ( = 0.916-0.964) describes the initial stage (≤35 PVs) well. Considering the functional group in the SP and the Hg species in groundwater, complexation, electrostatic attraction, ion exchange, and precipitation/co-precipitation are the plausible mechanisms for mercury removal based on the characterization results of scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectrometer (FT-IR). These impressive features render the SP a promising candidate for the remediation of trace Hg in saline groundwater using permeable reactive barrier (PRB) technology.
地下水中的汞污染严重影响人类健康和生态系统安全。汞污染地下水的修复仍然是一项具有挑战性的任务。通过批量试验和柱试验验证了一种合成的超分子聚合物（SP）在高盐度地下水基质中对低浓度汞的适用性。汞污染地下水的修复，特别是在复杂的高盐度环境中，是环境科学中一项重大且持久的挑战。批量试验研究表明，SP能以优异的选择性和高吸附容量（高达926.1±165.3 mg/g）从地下水中高效吸附汞。提高pH值和溶解有机物（DOM）并降低离子强度可促进汞的吸附；重金属离子的共存会略微削弱去除效果。就其作为渗透反应屏障的性能而言，SP能在流动的地下水中截留汞，截留容量高达3187 mg/g。低进水汞浓度、低孔隙流速和高SP投加量可有效延长柱试验中的穿透时间。此外，Yan模型（R² = 0.960 - 0.989）能准确描述固定柱中SP的整个动态截留过程（150个孔隙体积），Adams - Bohart模型（R² = 0.916 - 0.964）能很好地描述初始阶段（≤35个孔隙体积）。基于扫描电子显微镜（SEM）、X射线光电子能谱（XPS）和傅里叶变换红外光谱仪（FT - IR）的表征结果，考虑到SP中的官能团和地下水中的汞形态，络合、静电吸引、离子交换以及沉淀/共沉淀是汞去除的可能机制。这些令人印象深刻的特性使SP成为使用渗透反应屏障（PRB）技术修复咸水地下水中痕量汞的有前途的候选材料。
