沉积物产电信号原位在线监测水体铜污染研究  

Using electrical signals generated by sediments to in situ and on-line monitor copper pollution in water

作　　者：吴少松 邓欢 刘丽 王宵宵 孙宁欣 钟文辉 WU Shaosong;DENG Huan;LIU Li;WANG Xiaoxiao;SUN Ningxin;ZHONG Wenhui(School of Environment, Nanjing Normal University, Nanjing 210023;Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing 210023;School of Geography Science, Nanjing Normal University, Nanjing 210023)

机构地区：[1]南京师范大学环境学院,南京210000 [2]江苏省物质循环与污染控制重点实验室,南京210000 [3]南京师范大学地理科学学院,南京210000

出　　处：《环境科学学报》2018年第6期2454-2461,共8页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金项目(No.41671250);江苏省自然科学基金面上项目(No.BK20171476);江苏省高校自然科学研究面上项目(No.16KJB210007)~~

摘　　要：采用一种新型沉积物-微生物燃料电池(Sediment Microbial Fuel Cells,SMFCs)装置,探索产电信号原位在线监测湿地水体Cu^(2+)污染的可行性.采集水稻土装入烧杯并淹水以模拟湿地环境.将SMFCs装置的阳极不锈钢管插入水稻土,阴极淹没在上覆水中进行产电.采用数据采集卡在线记录电压.产电30 min后,分别向阴极附近的上覆水中加入5 mL Cu^(2+)浓度为50、100、200和400 mg·L^(-1)的CuSO_4溶液,对照加入5 mL去离子水,每个浓度处理设置两个平行.Cu^(2+)加入后,电压迅速上升并在30 s内达到峰值,之后随着Cu^(2+)扩散和被土壤吸附,电压回落并保持稳定.将加铜前30 min电压平均值作为基准电压,用加铜后的电压峰值减去基准电压得到电压增量.结果显示,电压增量与加入的Cu^(2+)浓度呈现显著正相关关系.为揭示相关机制,检测了CuSO_4溶液理化性质,并对加铜后SMFCs装置的阳极和阴极电荷传递电阻进行测定、对优势产电细菌梭菌属(Clostridium)和地杆菌科(Geobacteraceae)细菌16S rRNA基因进行定量.结果表明,Cu^(2+)促进阴极反应,是引起电压升高的主要原因.而底泥的吸附作用减弱了Cu^(2+)对产电细菌的抑制,保证了Cu^(2+)污染事件后产电信号恢复稳定.The present study was to evaluate the feasibility of in situ and on-line monitoring Cu（2＋）pollution in wetland water through electrical signals generated by a novel device based on sediment microbial fuel cells（ SMFCs）. The paddy soil was packed into beakers and submerged with deionized water. The anodic stainless pipe of the device was inserted into the paddy soil and the cathode was located in the overlaying water. The generated electricity was recorded with the data acquisition module. Thirty minutes after electricity was generated,5 mL CuSO_4 solution with 50,100,200 or 400 mg·L（-1） Cu（2＋）,and 5 mL deionized water for control treatment was added into the overlaying water near cathode. There are two replicate devices for each treatment.Immediately after Cu（2＋）was added,the voltage generated by all the devices increased and reached a peak within 30 s,followed by a decreasing trend due to Cu（2＋）diffusion and adsorption by soil. The mean voltage data before Cu（2＋）addition was defined as baseline voltage,and the difference between peak voltage and baseline voltage was defined as voltage increment. Results showed that the voltage increment positively correlated with added Cu（2＋）concentration. In order to illustrate related mechanisms,we measured physiochemical properties of CuSO_4 solution,along with the anodic and cathodic charge transfer resistance of the devices. Moreover,we quantified the 16 S rRNA gene of dominant exoelectrogenic bacterial groups including Clostridiumand Geobacteraceae. The result suggests that Cu（2＋）strongly enhanced cathodic reaction and thus increased voltage. The soil attenuated inhibitive effect of Cu（2＋）on exoelectrogenic bacteria,ensuring the stability of voltage after Cu（2＋）addition.

关 键 词：沉积物微生物燃料电池 湿地 三电极体系 电压 污染监测 

分 类 号：X703[环境科学与工程—环境工程]