Performance improvement of microbial fuel cells for waste water treatment along with value addition: A review on past achievements and recent perspectives

Due to depletion of fossil fuel and rapid industrial development there is urgent need to find environment friendly and sustainable technology for alternative energy. Microbial fuel cells (MFCs) are considered as a promising technology to extract energy from different sources and turn them into electricity. However, due to practical limitations, MFCs are still unsuitable for high energy demands. Since waste water contains several organic substances, therefore, production of electrical energy from waste water using MFC can offer an economical solution to the problem of environment pollution and energy crisis in near future. Therefore, the technological development for bioelectricity generation from waste water is becoming commercially worthwhile. In this review, discussion has been made critically on overall performance improvement strategies of microbial fuel cells and its application on waste water treatment along with effective power generation. The extensive research work has been carried out on microorganism selection, suitable MFC designs, appropriate electrode materials and optimum level of process parameters which would accelerate commercialization of this technology in near future. Therefore, this review has critically addressed the issues including usefulness of various cultures and their maintenance, applicability of different mode of operation and effectiveness of various MFCs to achieve sustainable power generation from waste water. In addition the various strategies for cost effective bioelectricity generation from waste water including novel reactor design as well as simultaneous treatment strategies have also been critically reviewed.

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