不同湿地植物构建植物沉积型微生物燃料电池的研究

Research on different wetland plants to construct the Plant-Sediment Microbial Fuel Cell

考察了粉黛万年青、小白掌、金边富贵竹、鹅掌柴4种湿地植物构建植物沉积型微生物燃料电池(Plant-Sediment Microbial Fuel Cell,Plant-SMFC)对电池基础特性的影响。试验结果表明:粉黛万年青、小白掌、金边富贵竹均可用来构建Plant-SMFC,并能显著提高SMFC的产电性能,其中小白掌电池组产电性能最优,Pmax为14.0 mW/m2,是空白的2.5倍。鹅掌柴在电池运行过程中烂根,不适合构建Plant-SMFC。阴阳极电极电位分析表明,各电池组输出电压的差异主要在于阳极电位的变化不同,而阴极电位变化基本一致且均在后期产生了一个大的跃迁,采用LSV验证了该跃迁的原因。最后利用HPLC分析证明了根系分泌有机酸的种类及含量与产电水平成正比,其中小白掌分泌有机酸种类及含量最多,有机酸总量达1.292 mg。

Four wetland plants（Dief fenbachia, Aconitum nagarum Stapf var, Dracaena Sanderiana, Schefflera octophylla （Lour.）Harms） were used to construct the Plant-SMFCs which were studied for their characteristics. The results showed that the plants all could be used to construct the Plant-SMFCs successfully except Schefflera octophylla （Lour.）Harms, which died due to the decay of root in the battery during operation. Aconitum nagarum Stapf var obviously improved the elec- tricity generation of SMFC, the obtained power density was the highest（14.0 mW/rn2）, which was 2.5 times that of the control. The investigation of potentials of anode and cathode demonstrated that anode potential was the key to impact the output voltage of SMFC, and the cathode potential in every SMFC has a similar trend that exsit a soar at latter period. Then LSV proved that because of the form of biocathode lead to the soar in cathode potential. Finally, the different root exudates of plants were analyzed by HPLC which indicated the more kinds and quantities of organic acids in root exudates, the higher electric power obtained from Aconitum nagarum Stapf var. total of organic acids reached 1.292 mg.