School of Energy and Environment, Southeast University, No.2 Sipailou Road, Nanjing 210096, PR China; ERC Taihu Lake Water Environment (Wuxi), No. 99 Linghu Road, Wuxi 214135, PR China.
School of Energy and Environment, Southeast University, No.2 Sipailou Road, Nanjing 210096, PR China.
Sci Total Environ. 2021 Aug 15;782:146549. doi: 10.1016/j.scitotenv.2021.146549. Epub 2021 Mar 18.
Oil spills near natural water bodies pose considerable threats to aquatic ecosystem and drinking water system. Various detection techniques have been developed to identify the oil pollution in natural waters. These techniques mainly focus on large and major oil spills involving significant changes in environmental characteristics. However, monitoring of minor oil spills (from seepage and dripping) in waters remains a bottleneck, allowing inconspicuous and persistent oil contamination. To overcome this drawback, a sediment microbial fuel cell (SMFC) sensor equipped with a vertical floating cathode is developed for on-line and in-situ monitoring of minor oil spills in natural waters. The vertical floating cathode was intended for recognizing oil on water surface. Oil on the cathode will trigger current drop. Two kinds of natural sediments were adopted in two sensors (SMFC1 from a lake and SMFC2 from an urban stream) for comparison. Both showed linear relationship between net steady-state current decrease and oil dose (30.78 and 27.29 μA/mL of sensitivity, respectively). The current change process was fitted well to a pseudo-first order kinetic equation. A one-point/two-point dynamic identification methods were derived from the kinetic equation. Therefore, the detection time was shortened from 10 h to 10/30 min. The triggered current decrease was mainly attributed to the increase in internal resistance related to charge and mass transfer. Despite the power loss after oil contamination, results implied SMFC sensor could still achieve self-sustainability. This study shows that the SMFC sensor with vertical floating cathodes is applicable to monitoring the unnoticeable minor oil pollutions in natural waters.
水体附近的溢油对水生态系统和饮用水系统构成了重大威胁。已经开发了各种检测技术来识别天然水中的石油污染。这些技术主要集中在涉及环境特征重大变化的大型和主要溢油上。然而，对水中的小型溢油（渗漏和滴漏）的监测仍然是一个瓶颈，允许不显眼和持续的油污污染。为了克服这一缺点，开发了一种配备垂直浮阴极的沉积物微生物燃料电池（SMFC）传感器，用于在线和原位监测天然水中的小型溢油。垂直浮阴极旨在识别水面上的油。油在阴极上会触发电流下降。两个传感器（一个来自湖泊的 SMFC1 和一个来自城市溪流的 SMFC2）采用了两种天然沉积物进行比较。两者的净稳态电流减少与油剂量之间均呈线性关系（灵敏度分别为 30.78 和 27.29 μA/mL）。电流变化过程很好地拟合了拟一级动力学方程。从动力学方程推导出了单点/两点动态识别方法。因此，检测时间从 10 小时缩短到 10/30 分钟。触发电流下降主要归因于与电荷和质量传递相关的内阻增加。尽管油污染后会损失功率，但结果表明 SMFC 传感器仍然可以实现自我可持续性。本研究表明，带有垂直浮阴极的 SMFC 传感器适用于监测天然水中不易察觉的小型溢油污染。
