• 한국수소및신에너지학회논문집
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• 제32권6호
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• pp.506-513
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• 2021

The use of fossil fuels is a major contributor to the increase atmospheric greenhouse gas emissions. As such problems arise, interest in new and renewable energy devices, particularly fuel cells, is greatly increasing. In this study, various characteristics of mixed strains were observed in wastewater collected by the Jeonju Environment Office to investigate the effects of microorganisms on voltage generation and voltage generation of substrates, electrode materials, electrons, electron transport media, and ash microbial fuel cells. As a result of separately measuring the voltage generated during inoculation, the inoculation voltage of Escherichia coli K12 (E. coli K12) was 0.45 V, and the maximum inoculation voltage of the mixed strain was 1.2 V. Thereafter, voltage values were collected using a digital multimeter and the amount of voltage generated over time was measured. In the case of E. coli K12, the maximum voltage reached 0.45 V, and the cell voltage was maintained above 0.23 V for 140 hours. In contrast, for the mixed strain, the maximum voltage reached 1.2 V and the voltage was slowly decreased to 0.97 V. In addition, the degree of microbial adsorption to the electrod surface after the inoculation test was confirmed using a scanning electron microscope. Therefore, these results showed the possibility of purifying pollutants at the same time as power generation through the production of hydrogen ions using microorganisms and wastewater.

• 한국환경농학회지
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• 제31권1호
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• pp.24-29
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• 2012

BACKGROUND: In recent years, microbial fuel cells (MFCs) have emerged as a promising technology for recovering renewable energy from waste biomass, especially wastewater. In this study, the possibility of bioelectricity generation in two chambered mediator-less microbial fuel cells (MFCs) was successfully demonstrated using fermentable and non-fermentable substrates. METHODS AND RESULTS: Two different electron acceptors have been tested in the cathode chamber for the effects of reducing agent on the power generation in MFCs. The average voltages of $0.26{\pm}0.014$ V and $0.36{\pm}0.02$ V were achieved with acetate using oxygen and potassium ferricyanide as reducing agent, respectively. Similarly, with glucose the average voltages of $0.256{\pm}0.05$ V and $0.340{\pm}0.04$ V were obtained using oxygen and ferricyanide, respectively. Using potassium ferricyanide as the reducing agent, the power output increases by 39 and 43% with acetate and glucose, respectively, as compared to the dissolved oxygen. Slightly higher coulombic efficiency (CE%) was obtained in acetate as compared to MFCs operated with glucose. The maximum power densities of 124 mW/$m^2$ and 204 mW/$m^2$ were obtained using dissolved oxygen and $K_3Fe(CN)_6$, respectively. CONCLUSION(s): This study demonstrates that power generation from the MFCs can be influenced significantly by the different types of catholyte. Relatively higher CE was obtained with $K_3Fe(CN)_6$. Thus, application of $K_3Fe(CN)_6$ as the catholyte can be vital for scaling uppower generation from the MFCs forreal time applications.

• Journal of Microbiology and Biotechnology
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• 제25권7호
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• pp.1114-1118
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• 2015

Microbial fuel cells (MFCs) have gathered attention as a novel bioenergy technology to simultaneously treat wastewater with less sludge production than the conventional activated sludge system. In two different operations of the MFC and aerobic process, microbial growth was determined by the protein assay method and their biomass yields using real wastewater were compared. The biomass yield on the anode electrode of the MFC was 0.02 g-COD-cell/gCOD-substrate and the anolyte planktonic biomass was 0.14 g-COD-cell/g-COD-substrate. An MFC without anode electrode resulted in the biomass yield of 0.07 ± 0.03 g-COD-cell/g-CODsubstrate, suggesting that oxygen diffusion from the cathode possibly supported the microbial growth. In a comparative test, the biomass yield under aerobic environment was 0.46 ± 0.07 g-COD-cell/g-COD-substrate, which was about 3 times higher than the total biomass value in the MFC operation.

• Korean Chemical Engineering Research
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• 제54권4호
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• pp.453-458
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• 2016

고분자전해질 연료전지용 MEA (Membrane and Electrode Assembly)와 돼지분뇨를 이용해 미생물연료전지(MFC)를 구동하였다. 미생물 연료전지에서 과불소계막과 탄화수소막의 성능을 비교하였다. 탄화수소막으로 sPAES 막을 사용하였고 과불소계막은 Gore 막을 사용했다. sPAES MEA가 Gore MEA보다 OCV는 50mV 높았고 출력 밀도는 비슷했다. sPAES 막을 강화시킴으로써 성능을 안정시킬 수 있었다. 미생물 연료전지의 셀 온도 $45^{\circ}C$에서 최고의 성능을 얻었고 배양액 순환속도 50 ml/min에서 최고의 성능을 얻었다. 최적 조건에서 돼지 분뇨를 이용한 미생물연료전지에서 최고 $1,100mW/m^2$의 출력 밀도가 발생하였다.

• 대한의용생체공학회:의공학회지
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• 제39권5호
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• pp.220-228
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• 2018

The internal resistance of microbial fuel cell (MFC) using stainless steel skein for oxidizing electrode was investigated and the factors affecting the voltage generation were identified. We also investigated the effect of power management system (PMS) on the usability for MFC and the removal efficiency of organic pollutants. The performance of a stack microbial fuel cell connected with (PMS) or PMS+LED was analyzed by the voltage generation and organic matter reduction. The maximum power density of the unit cells was found to be $5.82W/m^3$ at $200{\Omega}$. The maximum current density was $47.53A/m^3$ without power overshoot even under $1{\Omega}$. The ohmic resistance ($R_s$) and the charge transfer resistance ($R_{ct}$) of the oxidation electrode using stainless steel skein electrode, were $0.56{\Omega}$ and $0.02{\Omega}$, respectively. However, the sum of internal resistance for reduction electrode using graphite felts loaded Pt/C catalyst was $6.64{\Omega}$. Also, in order to understand the internal resistance, the current interruption method was used by changing the external resistance as $50{\Omega}$, $300{\Omega}$, $5k{\Omega}$. It has been shown that the ohm resistance ($R_s$) decreased with the external resistance. In the case of a series-connected microbial fuel cell, the reversal phenomenon occurred even though two cells having the similar performance. However, the output of the PMS constantly remained for 20 hours even when voltage reversal occurred. Also the removal ability of organic pollutants (SCOD) was not reduced. As a result of this study, it was found that buffering effect for a certain period of time when the voltage reversal occurred during the operation of the microbial fuel cell did not have a serious effect on the energy loss or the operation of the microbial fuel cell.

• Environmental Engineering Research
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• 제19권4호
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• pp.363-367
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• 2014

One chambered sediment microbial fuel cell (SMFC) was equipped with Fe, brass (Cu/Zn), Fe/Zn, Cu, Cu/carbon cloth and graphite felt anode. Graphite felt was used as common cathode. The SMFC was membrane-less and mediator-less as well. Order of anodic performance on the basis of power density was Fe/Zn ($6.90Wm^{-2}$) > Fe ($6.03Wm^{-2}$) > Cu/carbon cloth ($2.13Wm^{-2}$) > Cu ($1.13Wm^{-2}$) > brass ($Cu/Zn=0.24Wm^{-2}$) > graphite felt ($0.10Wm^{-2}$). Fe/Zn composite anode have twisted 6.73% more power than Fe alone, Cu/carbon cloth boosted power production by 65%, and brass (Cu/Zn) produced 65% less power than Cu alone. Graphite felt have shown the lowest electricity generation because of its poor galvanic potential. The estuarine sediment served as supplier of oxidants or electron producing microbial flora, which evoked electrons via a complicated direct microbial electron transfer mechanism or making biofilm, respectively. Oxidation reduction was kept to be stationary over time except at the very initial period (mostly for sediment positioning) at anodes. Based on these findings, cost effective and efficient anodic material can be suggested for better SMFC configurations and stimulate towards practical value and application.

• 대한환경공학회지
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• 제31권9호
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• pp.705-718
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• 2009

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2005년도 춘계총회 및 학술발표회
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• pp.29-29
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• 2005

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2003년도 춘계총회 및 학술발표회
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• pp.10-10
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• 2003

• 한국토양비료학회지
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• 제45권3호
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• pp.410-420
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• 2012

The heavy reliance on fossil fuels, especially oil and gas has triggered the global energy crisis. Continued use of petroleum fuels is now widely recognized as unsustainable because of their depleting supplies and degradation to the environment. To become less dependent on fossil fuels, current world is shifting paradigm in energy by developing alternative energy sources mainly through the utilization of renewable energy sources. In particular, bioenergy recovery from wastes with the help of microorganism is viewed as one of the promising ways to mitigate the current global warming crisis as well as to supply global energy. It has been proved that microorganism can generate power by converting organic matter into electricity using microbial fuel cells (MFCs). MFC is a bioelectrochemical device that employs microbes to generate electricity from bio-convertible substrate such as wastewaters including municipal solid waste, industrial, agriculture wastes, and sewage. Sustainability, carbon neutral and generation of renewable energy are some of the major features of MFCs. However, the MFC technology is confronted with a number of issues and challenges such as low power production, high electrode material cost and so on. This paper reviews the recent developments in MFC technology with due consideration of electrode materials used in MFCs. In addition, application of biocathodes in MFCs has been discussed.