微生物燃料电池藻阴极性能比较及膜污染分析

为考察藻种类及阴极材料对藻阴极型微生物燃料电池性能的影响,以微藻及水绵为阴极生物,分别采用碳毡,碳纸,载铂碳纸为阴极材料,构建了微生物燃料电池。结果显示,以碳毡作为阴极材料时,2种藻阴极微生物燃料电池最大功率密度均高于以碳纸为阴极材料时相应的功率密度。采用载铂碳纸为阴极材料、天然湖水为阴极液,微生物燃料电池最大功率密度分别达到165.1 mW/m2(微藻阴极)和119.9 mW/m2(水绵阴极)。电化学测试表明,藻类生长形态影响了阴极的电化学特征,进而影响到了微生物燃料电池的性能。藻阴极MFC长期运行时,膜污染是藻阴极微生物燃料电池功率密度下降的关键因素之一。SEM-EDS分析显示,膜两侧污染主要原因分别是微生物生长和磷酸盐晶体沉积。

Comparison of algal cathodes in a microbial fuel cell and analysis to fouling of membrane

To investigate the influence of algae and construction materials on the performance of algal microbial fuel cells, carbon felt, carbon paper, and Pt-coated carbon paper were used as construction materials for the cathodes of algal microbial fuel cells (MFCs) with Spirogyra sp. and microalgae as cathodic microorganisms. The maximum power densities of MFCs with carbon felt cathodes were higher than those of MFCs with carbon paper cathodes (with and without Pt coating). The maximum power densities of MFCs of Pt-coated carbon paper cathodes using microalgae and Spirogyra sp. as cathodic microorganisms were 165.1 mW/m2 and 119.9 mW/m2, respectively. Electrochemical tests indicated that algal morphology affected the electrochemical characteristics of the cathodes and the performance of the MFCs. Membrane fouling is one of the root causes of reduced performance of algal MFCs in long-term operations. The results of SEM-EDS demonstrated that membrane fouling was caused by microorganisms and phosphate crystal sediment on the support layer and surface, respectively.