铁锰复合阴极MFC-EF耦合系统产电及降解RhB效能

Electricity production and RhB degradation in MFC-EF coupling system with iron and manganese composite cathode

摘要:

为实现微生物燃料电池（MFC）微电的原位利用,结合电芬顿（EF）技术的优势,构建MFC-EF耦合系统.为进一步提高该耦合系统性能,在Fenton催化剂铁的基础上引入类芬顿（Fenton-like）催化剂锰,制备出铁锰双金属复合阴极（FeMnO_x/CF复合电极,其中CF指碳纤维刷）,并与碳纤维（CF）无负载电极、Fe&Fe₂O₃/CF复合电极对比,探究MFC-EF耦合系统的电化学性能及其对目标污染物罗丹明B（RhB）的降解效果.结果表明,铁锰复合电极成功负载了Fe和Mn的二元金属氧化物,提高了耦合系统的最大输出功率（5.47 W/m³）,降低了电池的内阻（109.00 Ω）,提高了RhB的去除率（91.60%）和矿化率（30.84%）.此外,FeMnO_x/CF复合电极摆脱了常规Fenton体系对阴极液pH的严格限制,扩大了MFC-EF耦合系统的阴极液pH范围.本研究实现了污染物处理过程中的资源再生和利用,有望为实际染料废水处理提供新的思路.

Abstract:

In order to realize in-situ utilization of weak current generated in microbial fuel cell (MFC), an MFC-EF coupling system was constructed by utilizing the advantages of electro-Fenton (EF) technology. To further improve the performance of the coupling system, a composite cathode of iron and manganese (FeMnO_x/CF composite electrode, CF refers to carbon fiber brush) was prepared, which introduced Fenton-like catalyst manganese on the basis of Fenton catalyst iron. The electrochemical performance of the MFC-EF coupling system and its degradation effect on Rhodamine B (RhB) were investigated by being compared with CF unloaded electrode and Fe&Fe₂O₃/CF composite electrode. Results showed that FeMnO_x/CF composite electrode was successfully loaded with the binary metal oxides of Fe and Mn. The maximum output power of the coupling system was improved (5.47 W/m³), the internal resistance of the MFC was reduced (109.00 Ω), and both the removal rate (91.60%) and mineralization rate (30.84%) of RhB were increased. Besides, the FeMnO_x/CF composite electrode was free from the strict restriction of catholyte pH in conventional Fenton system, and the pH range of catholyte in MFC-EF coupling system was expanded. The study can realize the regeneration and utilization of resources in the process of pollutant removal, which is expected to provide a new idea for practical dye wastewater treatment.