Md. T. Noori

Biofouling inhibition and enhancing performance of microbial fuel cell using silver nano-particles as fungicide and cathode catalyst.

Morphological analysis of biofouling developed on cathode surface in an air-cathode microbial fuel cell (MFC) was performed. For sustaining power production and enhancing Coulombic efficiency (CE) of MFC, studies were conducted to inhibit cathode biofouling using different loadings of silver nanoparticles (Ag-NPs) with 5% and 10% Ag in carbon black powder. In MFC without using Ag-NPs in cathode (MFC-C), cathode biofouling increased the charge transfer resistance (Rct) from 1710Ω.cm(2) to 2409Ω.cm(2), and reduced CE by 32%; whereas in MFC with 10% Ag in cathode Rct increased by only 5%. Power density of 7.9±0.5W/m(3) in MFC using 5% Ag and 9.8±0.3W/m(3) in MFC using 10% Ag in cathode was 4.6 and 5.7-folds higher than MFC-C. These results suggest that the Ag-NPs effectively inhibit the fungal biofouling on cathode surface of MFCs and enhanced the power recovery and CE by improving cathode kinetics.

Controlling methanogenesis and improving power production of microbial fuel cell by lauric acid dosing

Methanogens compete with anodophiles for substrate and thus reduce the power generation and coulombic efficiency (CE) of the microbial fuel cell (MFC). Performance of a baked clayware membrane MFC inoculated with mixed anaerobic sludge pretreated with lauric acid was investigated in order to enhance power recovery by controlling methanogenesis. In the presence of lauric acid pretreated inoculum, MFC produced maximum volumetric power density of 4.8 W/m(3) and the CE increased from 3.6% (for untreated inoculum) to 11.6%. Cyclic voltammetry (CV) and electro-kinetic evaluation indicated a higher bio-catalytic activity at the anode of the MFC inoculated with lauric acid pretreated sludge. With the lauric acid pretreated inoculum a higher catalytic current of 114 mA, exchange current density of 40.78 mA/m(2) and lower charge transfer resistance of 0.00016 Ωm(2) were observed during oxidation at the anode. Addition of lauric acid significantly achieved suppression of methanogenesis and enhanced the sustainable power generation of MFC by 3.9 times as compared with control MFC inoculated with sludge without any pretreatment.

Enhanced Power Generation in Microbial Fuel Cell Using MnO2-Catalyzed Cathode Treating Fish Market Wastewater

Development of cost effective metal-based catalyzed cathode for enhancing oxygen reduction reaction (ORR) is necessary to produce higher power in microbial fuel cell (MFC). In this study, γ-MnO2 was synthesized using chemical co-precipitation method and tested in MFC as cathode catalyst. Two single chamber MFCs, one with γ-MnO2 catalyzed cathode (MFC-M) coated with carbon supported MnO2 (0.5 mg cm−2) on cathode and other control MFC (MFC-C) coated without catalyst in cathode, were fabricated using clayware cylinders. Maximum power density of 1.66 and 0.5 W m−3 with a coulombic efficiency (CE) of 9 ± 0.65 % and 4.6 ± 0.26 % was obtained in MFC-M and MFC-C, respectively. The average organic matter removal efficiencies in terms of chemical oxygen demand (COD) were found to be 84.4 ± 3.4 % and 75 ± 1.4 % and total nitrogen removal efficiencies of 66.5 ± 2.56 % and 52.8 ± 3.17 % were achieved in MFC-M and MFC-C, respectively. MFC-M demonstrated enhanced ORR and subsequent increase in electrochemical activity on cathode, thereby improving power generation and substrate degradation. The present study shows the applicability of cost-effective metal-based (γ-MnO2) catalyst for scaling-up of air-cathode MFCs to treat fish market wastewater, which can also be used for treatment of other organic matter containing wastewater.

Experimental study to evaluate the efficacy of locally available waste carbon sources on aquaculture water quality management using biofloc technology

Locally available carbonaceous waste products viz. wheat flour, rice flour and tapioca flour recovered from flour industries were explored as carbon source for biofloc production and water quality management in light limited indoor aquariums without any culture species. The main objective of the study was to find out the efficacy of locally available waste carbon sources on biofloc production. Tapioca flour was found to be encompassed with more than 90% carbohydrate and was observed more suitable for microbial growth, resulting in 41.4 and 33.7% higher floc formation as compared to rice flour and wheat flour, respectively. In addition, enhanced microbial protein assimilation of 33.5% was noted in tapioca flour biofloc system with respect to wheat flour (27%) and rice flour (23.75%). All biofloc systems showed adequate water quality management in terms of nitrite and total ammonium nitrogen removal from the culture tank. The study demonstrates the effective use of waste products from flour industries in biofloc technology to obtain multi-layer benefit as waste minimization and water treatment.

Novel application of peptaibiotics derived from Trichoderma sp. for methanogenic suppression and enhanced power generation in microbial fuel cells

Correction for ‘Novel application of peptaibiotics derived from Trichoderma sp. for methanogenic suppression and enhanced power generation in microbial fuel cells’ by M. M. Ghangrekar et al., RSC Adv., 2017, 7, 10707–10717.

Sediment Microbial Fuel Cell and Constructed Wetland Assisted with It: Challenges and Future Prospects

In recent years, the research work focus in energy sector has been shifted towards the renewable energy due to continuous depletion of conventional energy sources. On the other hand, exponentially increasing pollution in water reserves has stimulated phenomenal debates among researchers, pollution control agencies, and stakeholders in search of sustainable solution to remediate it. Sediment microbial fuel cell (SMFC) is one of the most promising approaches to address these two highly recognized problems together (Sajana et al. 2013b). In addition, SMFCs can offer distinctive opportunity to understand the flow of energy through electrochemically active bacteria, energy collection efficiency from natural systems, and the role of SMFCs for power generation and in situ bioremediation in the natural environment (Sajana et al. 2013a). SMFCs comprise two electrically conductive electrodes as anode and cathode placed 5–10 cm beneath the free surface of sediment and free water surface, respectively (Fig. 17.1a). Chemical energy associated with organic matter present in the sediment and water gets converted to electron and proton during oxidation catalyzed by microorganisms, working as biocatalyst on anode surface. Sediment permits the flow of protons from anode to cathode side serving as proton permeable natural medium. The anode collects extracellular electrons and transfer them to the cathode through an external circuit. On cathode, oxygen or other chemical oxidant (like nitrate) serve as terminal electro acceptor (TEA), which combines with electron and proton and produce water or other reduced product (Rismani-Yazdi et al. 2008). In addition, anions and cations can be used for charge balanced in the SMFCs based on their concentration in the fluid (Kim et al. 2007). Natural phenomenon of redox charge gradient have been used for development of SMFCs. Table 17.1 shows the brief summary of half-cell equations (anodic and cathodic) which can take place on anode and cathode during bioconversion of organic matter to electricity.

Utilisation of waste medicine wrappers as an efficient low-cost electrode material for microbial fuel cell

ABSTRACT Waste generation from healthcare facilities now has become a concerning issue as it contain plastic and metals. Medicine wrappers are one of the major portions of healthcare solid waste, which impel intensive solid waste management practice due to fewer possibilities of deriving by-products. However, it can be recycled and used as an electrode material in microbial fuel cells (MFCs). An electrode material for application in MFCs is a crucial component, which governs total fabrication cost as well as power recovery, thus a cost-effective, stable and durable electrode is essential. In this endeavour, a new metallic (aluminium) waste material, a waste medicine wrapper (WMW), was evaluated for feasibility to be used as anode/cathode in MFCs. Based on the stability test under corrosive environment (1 N KCl), the WMW electrode sustained a maximum current of 46 mA during cyclic voltammetry (CV) and noted only 14% reduction in current at an applied voltage of +0.4 V after 2500 s in chronoamperometry, indicating its good stability. Power recovery from MFC using WMW was higher than the MFC using bare carbon felt as an anode (27 vs. 21 mW/m2). The entire analytical test results viz. CV, electrochemical impedance spectroscopy and power performance established WMW as an excellent anode rather than cathode material. GRAPHICAL ABSTRACT