Department of Civil and Environmental Engineering, The Pennsylvania State University, University Park, PA 16802, USA.
Water Res. 2012 May 1;46(7):2215-24. doi: 10.1016/j.watres.2012.01.050. Epub 2012 Feb 10.
Nitrogen removal is needed in microbial fuel cells (MFCs) for the treatment of most waste streams. Current designs couple biological denitrification with side-stream or combined nitrification sustained by upstream or direct aeration, which negates some of the energy-saving benefits of MFC technology. To achieve simultaneous nitrification and denitrification, without extra energy input for aeration, the air cathode of a single-chamber MFC was pre-enriched with a nitrifying biofilm. Diethylamine-functionalized polymer (DEA) was used as the Pt catalyst binder on the cathode to improve the differential nitrifying biofilm establishment. With pre-enriched nitrifying biofilm, MFCs with the DEA binder had an ammonia removal efficiency of up to 96.8% and a maximum power density of 900 ± 25 mW/m(2), compared to 90.7% and 945 ± 42 mW/m(2) with a Nafion binder. A control with Nafion that lacked nitrifier pre-enrichment removed less ammonia and had lower power production (54.5% initially, 750 mW/m(2)). The nitrifying biofilm MFCs had lower Coulombic efficiencies (up to 27%) than the control reactor (up to 36%). The maximum total nitrogen removal efficiency reached 93.9% for MFCs with the DEA binder. The DEA binder accelerated nitrifier biofilm enrichment on the cathode, and enhanced system stability. These results demonstrated that with proper cathode pre-enrichment it is possible to simultaneously remove organics and ammonia in a single-chamber MFC without supplemental aeration.
在微生物燃料电池（MFC）中需要进行氮去除，以处理大多数废水。目前的设计将生物反硝化与侧流或联合硝化相结合，硝化由上游或直接曝气维持，这否定了 MFC 技术的一些节能优势。为了在不额外曝气的情况下实现同时硝化和反硝化，在单室 MFC 的空气阴极上预先富集硝化生物膜。二乙胺官能化聚合物（DEA）被用作阴极上的 Pt 催化剂粘合剂，以改善差分硝化生物膜的建立。使用预先富集的硝化生物膜，具有 DEA 粘合剂的 MFC 的氨去除效率高达 96.8%，最大功率密度为 900±25 mW/m(2)，而使用 Nafion 粘合剂的效率为 90.7%和 945±42 mW/m(2)。缺乏硝化生物膜预富集的 Nafion 对照物去除的氨更少，产生的功率更低（最初为 54.5%，750 mW/m(2)）。硝化生物膜 MFC 的库仑效率（高达 27%）低于对照反应器（高达 36%）。具有 DEA 粘合剂的 MFC 的最大总氮去除效率达到 93.9%。DEA 粘合剂加速了阴极上硝化生物膜的富集，并增强了系统的稳定性。这些结果表明，通过适当的阴极预富集，可以在无需补充曝气的情况下，在单室 MFC 中同时去除有机物和氨。
