Azo dyes are synthetic colors used in the textile, leather, food, and cosmetic industries. They are also a significant source of water pollution because they are resistant to biodegradation and can affect aquatic life and human health. Toxicity, carcinogenicity, mutagenicity, and impaired sunlight transmission are among the impacts. To break down azo dyes from wastewater, several physicochemical approaches have been applied. In terms of efficiency, cost, energy consumption, and environmental effects, these approaches offer varied advantages and drawbacks. As a result, selecting the best procedure for a certain dye and wastewater condition is critical. Microbial degradation of azo dyes is a process in which microorganisms, such as bacteria, fungi, or algae, employ enzymes to break down the dye molecules’ azo bonds and aromatic rings. The dye wastewater may be decolored, detoxified, and mineralized as a result of this procedure. Depending on the kind of bacteria and the availability of oxygen, azo dye degradation can proceed in aerobic or anaerobic settings. Microbial degradation of azo dyes is a viable alternative to biological approaches since it is environmentally safe, cheap, and efficient. Microbial fuel cells (MFCs) are devices that turn organic materials into energy using microorganisms. They may also be used to remove azo dyes from wastewater because the dye molecules can act as electron donors for the microorganisms in the MFC’s anode chamber. The biodegradation of azo dyes in MFCs consists of two steps: anaerobic bacteria in the anode reductively cleave the azo bonds, and aerobic microorganisms in the cathode or a post-treatment unit oxidize the aromatic amines. Electrons generated during dye degradation are transmitted to the anode, and subsequently to the cathode through an external circuit, resulting in the generation of electricity. Studies have reported degradation efficiencies of up to 90% for Congo Red and Acid Orange 7 under optimized conditions in MFCs. This review mainly focusses on the biodegradation of azo dyes with the help of microbial fuel cells, the principle of azo dye degradation with the help of microbial fuel cells, and different factors that affect the biodegradation of azo dyes with the help of microbial fuel cells.

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用于降解偶氮染料的微生物燃料电池：透视综述


偶氮染料是用于纺织、皮革、食品和化妆品行业的合成色素。它们也是水污染的重要来源，因为它们难以生物降解，并且会影响水生生物和人类健康。其影响包括毒性、致癌性、致突变性和阳光透射受损。为了分解废水中的偶氮染料，已经应用了几种物理化学方法。在效率、成本、能源消耗和环境影响方面，这些方法各有优点和缺点。因此，针对特定染料和废水条件选择最佳程序至关重要。偶氮染料的微生物降解是细菌、真菌或藻类等微生物利用酶分解染料分子的偶氮键和芳香环的过程。此过程可对染料废水进行脱色、解毒和矿化。根据细菌的种类和氧气的可用性，偶氮染料的降解可以在有氧或厌氧环境中进行。偶氮染料的微生物降解是生物方法的可行替代方案，因为它对环境安全、廉价且高效。微生物燃料电池（MFC）是利用微生物将有机材料转化为能量的装置。它们还可用于去除废水中的偶氮染料，因为染料分子可以充当 MFC 阳极室中微生物的电子供体。 MFC中偶氮染料的生物降解包括两个步骤：阳极中的厌氧细菌还原性裂解偶氮键，阴极或后处理单元中的需氧微生物氧化芳香胺。 染料降解过程中产生的电子被传输到阳极，随后通过外部电路传输到阴极，从而产生电力。研究报告称，在 MFC 的优化条件下，刚果红和酸性橙 7 的降解效率高达 90%。本文主要讨论了微生物燃料电池对偶氮染料的生物降解、微生物燃料电池降解偶氮染料的原理以及影响微生物燃料电池对偶氮染料生物降解的不同因素。