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Closed circuitry operation influence on microbial electrofermentation: Proton/electron effluxes on electro-fuels
G N Nikhil1, G Venkata Subhash1, Dileep Kumar Yeruva1
1Bioengineering and Environmental Sciences (BEES), CSIR-Indian Institute of Chemical Technology, Hyderabad, India.
Bioresource Technology
|July 21, 2015
Summary
A novel biocatalyzed electrofermentor (BEF) efficiently generates electricity and hydrogen fuel. Optimal performance was achieved with a 100 Ω external resistance, maximizing power and fuel output from wastewater.
Area of Science:
- * Bioelectrochemistry and Renewable Energy Systems
- * Microbial Electrochemistry and Fuel Production
Background:
- * Biocatalyzed electrofermentors (BEFs) are emerging technologies for simultaneous wastewater treatment and energy generation.
- * Understanding the influence of operational parameters, such as external resistance, is crucial for optimizing BEF performance.
Purpose of the Study:
- * To investigate the role of external resistance (Rext) on the performance of a novel biocatalyzed electrofermentor.
- * To evaluate the cogeneration of electro-fuels (hydrogen and electricity) under varying electrical loads.
- * To assess the sustainability of the BEF system for renewable energy harvesting.
Main Methods:
- * Design and operation of four BEFs with different external resistances (25, 50, 100, and 200 Ω).
- * Operation at a constant organic load of 5 g/L.
- * Voltammetric analyses to probe electron kinetics and redox protein activity.
Main Results:
- * The BEF operated at 100 Ω (R3) achieved maximum power output (148 mW) and cumulative hydrogen production (450 mL).
- * Closed circuitry conditions enhanced metabolic activity of electroactive bacteria (EAB), leading to higher substrate degradation and fuel productivity.
- * Electron transfer via redox proteins was confirmed through voltammetric studies.
Conclusions:
- * External resistance significantly impacts the performance of biocatalyzed electrofermentors.
- * A 100 Ω resistance is optimal for maximizing energy and hydrogen production in the designed BEF.
- * The developed BEF is a sustainable system for wastewater treatment and renewable energy generation.
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