碳粉催化剂镍基体空气阴极微生物燃料电池特性研究

试验以泡沫镍材料作为空气阴极MFC的电极材料,并利用碳粉作为催化剂,在1.24 A/m2的电流密度下获得了214 mW/m2的最大功率密度输出。电位分析结果表明,阴极开路电位为+12 mV,阳极开路电位为-466 mV。采用改变外阻的调节方式,获得了18.6%~57.8%的库伦效率。试验结果表明,碳粉可以作为催化剂材料在泡沫镍基体空气阴极MFC系统中使用。     

单室空气阴极微生物燃料电池处理模拟生活废水同步产电研究

以某生活污水处理站厌氧池活性污泥为混合菌种,以葡萄糖为模拟生活废水,构建单室微生物燃料电池.利用微生物燃料电池实验生活废水降解与同步产电.实验结果表明:当葡萄糖浓度控制10mmol·L-1,pH值为7,温度控制在35℃时,其输出电压最大为0.486V,COD去除率最高为46.11％.微生物燃料电池(MFC)具有最佳的电化学性能.     

活性炭与TiO_2混合催化镍基体生物阴极微生物燃料电池性能研究

以发泡镍为基体,柱状活性炭颗粒和Ti O2粉末均匀混合后作为催化剂涂覆在电极表面。将此复合电极作为双室生物阴极型MFC的电极,研究MFC的产电性能。结果表明:在运行周期内,系统最大输出电压可达到698.1 m V,稳定在500 m V以上的高电压输出时间为18 d;单位质子膜面积上可获得最大功率密度为183.33W/m4,质子膜的使用量明显减少,从而大大降低了MFC的产电成本。同时,阳极室对原生活污水COD去除率可达到74%,而库伦效率也可达到68.9%。试验结果表明,活性炭和Ti O2混合涂覆镍基体电极对双室生物阴极型MFC产电的催化效果良好。     

单室微生物燃料电池产电特性研究

采用石墨板为阴极构建了单室空气阴极微生物燃料电池(MFC),以混合菌种接种,并以乙酸钠和碳酸氢钠为碳源,研究了该MFC在间歇运行条件下的产电性能、电池内阻情况和COD去除率。结果表明,最高输出电压随着周期数增加而增加,由0.075 9 V上升到0.200 6 V,最大输出功率密度为34.80 mW/m2;在一个运行周期内,电池内阻随着时间的延长而逐渐增大,由376.6Ω上升到682.0Ω,电池内阻的增大将导致输出电压降低。COD去除率由起始的49.23%达到最大值86.99%,说明此单室空气阴极微生物燃料电池在产电的同时处理污水的效果也较好。     

微生物燃料电池阴极电子受体与结构的研究进展

从工程应用的角度分析了微生物燃料电池的结构变化趋势;从电化学角度介绍了几种两室微生物燃料电池中阴极室采用不同电子受体对提高电池输出功率的影响和单室空气阴极微生物燃料电池的研究现状及应用前景;分析了电池组在电池放大过程中可能存在的串挠和电压反转等问题,为微生物燃料电池的工程应用提供了理论参考。     

阴极电子受体对微生物燃料电池性能的影响

以双室型微生物燃料电池为试验装置,比较铁氰化钾、重铬酸钾、高锰酸钾作为阴极电子受体时微生物燃料电池的电压和功率输出。结果表明,高锰酸钾与重铬酸钾混合电子受体对微生物燃料电池性能的提高没有显著效果,不如两者的单独表现;高锰酸钾对应的最高输出电压可达1 160 mV,但很不稳定,会很快下降到600 mV左右,在实际应用中有一定障碍;在酸性条件(pH=3.0)下,重铬酸钾的开路电压为1 081.2 mV,最大输出功率密度为35.1 W/m3,电池内阻为170.27Ω,而且表现稳定,是理想的阴极电子受体。     

微生物燃料电池中产电微生物的研究现状

随着我国社会的不断发展进步,各种环境污染问题成为科技发展首要控制的环保因素。微生物燃料电池是新开发的一种能源,其原理是利用微生物将有机物中的化学能转化成电能的过程,从而形成一种产电的装置,产电微生物作为一种催化剂来说,对微生物燃料电池有着至关重要的作用。产电微生物的种类不同也决定着他们的电子转移能力不同,导致微生物燃料电池的产电性能也不相同,电池的不同也致使了他们在实际工程中有着不同的用途。日常生活中产生的废水、沉积物等含有大量微生物的物质都可以成为产电微生物的工作来源,可以在任何环境下选取有效的产电微生物来作为微生物燃料电池的生物催化剂。文章主要对微生物燃料电池中的产电微生物进行了研究,并且对如何更好地发展微生物燃料电池进行了讨论。     

微生物燃料电池运行影响因素的研究

研究自行设计的微生物燃料电池在常温常压下,以厌氧污泥为接种源,以葡萄糖为底物原料,以不同溶液作为电子受体的条件下测试其稳定运行的影响因素与工艺条件。实验结果表明:该微生物燃料电池可稳定运行约30d,并在注入新的底物后,电压又快速回升至稳定电压。以铁氰化钾溶液作为电子受体,输出电压可达0.75V,输出功率为2100mW/m~2;以高锰酸钾溶液作为电子受体,输出电压为1.023V,输出功率为2638mW/m~2。     

石墨束微生物燃料电池产电性能研究

试验研究了以乙酸钠为燃料,以石墨束为阳极的双室微生物燃料电池的产电情况.试验结果表明,经过6d的启动期,电池输出电压达到稳定状态,以乙酸钠为燃料时最大输出电压可达到698mV,并可持续10d左右,电池内阻为44.6Ω,最大体积功率密度可达6 321.1 mW/m3,最大面积功率密度为745.5 mW/m2,COD的去除率可达85%以上.燃料电池在外阻为510Ω条件下运行1个周期,其库仑效率约为20%.     

不同接种物对微生物燃料电池利用氨氮产电的影响

文章以厌氧污泥和河底沉积物分别启动单室微生物燃料电池MFC,并通过改变氨氮浓度以及外电阻大小考察其对于MFC产电和氨氮去除的影响。结果表明,不同接种物启动的MFC对氨氮浓度的耐受性不同,厌氧污泥MFC在氨氮浓度为488.2 mg/L时最大输出功率Pmax为454.6 mW/m2,而沉积物MFC的Pmax为309.6mW/m2,出现在氨氮浓度为127.5 mg/L时;小电阻有利于氨氮的去除,但会限制MFC的产电,当外电阻从1 000Ω降低到10Ω时,厌氧污泥MFC氨氮去除率从46.1%提高到71.9%,沉积物MFC则从41.0%提高到了69.3%,并且厌氧污泥接种的MFC氨氮去除率与电阻的线性关系要优于沉积物MFC。     

Treatment of seafood industrial wastewater coupled with electricity production using air cathode microbial fuel cell under saline condition

The present study investigated seafood industrial wastewater treatment with corresponding power generation in air cathode microbial fuel cell under saline condition (40 g/L). The results recorded total chemical oxygen demand) removal of 52 ± 1.8%, 64 ± 1.1%, 85 ± 1.2%, 89 ± 1.4%, and 76 ± 1.2% to the corresponding organic load (OL) of 0.5, 0.75, 1, 1.25, and 1.5 gCOD/L under saline condition. Soluble chemical oxygen demand reduction was in the range of 46% to 78% at OL of 0.5 to 1.5 gCOD/L. The maximum power density (530 ± 15 mW/m²) and coulombic efficiency (52 ± 2.4%) was procured at the OL of 1.25 and 0.5 gCOD/L, respectively. Total suspended solids removal was 74 ± 1.5% at OL of 1.25 gCOD/L and 64 ± 1.3% at OL 1.5 gCOD/L. Bacterial community analysis for anode region samples for OL 0.5 and 1 gCOD/L was extensively dominated by Bacillus (MN880233) with 75.8% and 55.8%, respectively. Interestingly at 1.25 gCOD/L OL, Rhodococcus (MN880237) was predominant (42.3%) strain in the anode region and recorded high power production under saline condition. Sludge samples subjected to phylogenetic analysis explored the dominance of Clostridium, Turicibacter, and Marinobacter at different OL from 0.5 to 1.5 gCOD/L. Bacterial community results at 1.25 gCOD/L of OL sludge samples revealed completely different strains of dominancy in the community. Marinobacter (53.3%), Ochrobactrum (19.3%), and Bacillus (8.1%). Thus, the phylogenetic analysis of the anodic and sludge samples clearly detailed the presence of halophilic bacterial strains with high potential to treat seafood processing industrial wastewater and excellent exoelectrogenic activity for power production.     

Nanostructured silver catalyzed nickel foam cathode for an aluminum–hydrogen peroxide fuel cell

A nanostructured Ag catalyzed nickel foam cathode for an aluminum–hydrogen peroxide fuel cell was prepared using an electrodeposition technique. SEM images show that Ag nano-islands, about 2–3 μm in length and 100–200 nm in width are aligned on the surface of the Ni foam substrate. The composition of the catalyst layer of the cathode was examined by XRD. Electrochemical performance and stability of the cathode for the reduction of hydrogen peroxide in aluminum–hydrogen peroxide fuel cell were studied.     

Surface floating, air cathode, microbial fuel cell with horizontal flow for continuous power production from wastewater

A surface floating, air cathode, microbial fuel cell (MFC) with a horizontal flow is devised and characterized using glucose-based synthetic wastewater. The performance of the MFC is significantly affected by the current-collector of the electrodes. When graphite foil ribbon (150 cm) serves as the current-collector, the respective specific internal resistance and maximum power density are 0.362 Ω m⁻² and 124.0 W m⁻³. The internal resistance can be reduced by increasing the length of the current-collector. For a graphite ribbon current-collector 256 cm long, the specific internal resistance is only 0.187 Ω m⁻² and the maximum power density markedly increases to 253.6 W m⁻³; however, the maximum power density is affected by the current-collector material. When the current-collector is changed to a stainless-steel wire, the maximum power density is reduced to approximately 100 W m⁻³ because of its high liquid|solid interfacial impedance. During three continuous months of operation, issues such as leaking are not observed and as such, the MFC could be easily scaled-up for wastewater treatment by increasing the electrode size and stacking a number of cells without additional ohmic resistance.     

Copper-phthalocyanine and nickel nanoparticles as novel cathode catalysts in microbial fuel cells

In this study, four different catalysts (i.e., carbon black, nickel nanoparticle (Ni)/C, Phthalocyanine/C and copper-phthalocyanine/C), were tested in a two-chamber Microbial Fuel Cell (MFC) and their performances were compared with Pt as the common cathode catalyst in MFC. The characterization of catalysts was done by TEM, XPS and EDX and their electrochemical characteristics were compared by cyclic voltammetry (CV) and Linear Sweep Voltammetry (LSV). The results proved that copper phthalocyanine and nickel nanoparticles are potential alternatives catalyst for Pt. Even copper-phthalocyanine generated power is almost the same as Pt. The CV and LSV results reported high electrochemical activity of these catalysts. The maximum power density and coulombic efficiency was achieved by copper-phthalocyanine/C as 118.2 mW/m² and 29.3%.     

Biocatalyzed hydrogen production in a continuous flow microbial fuel cell with a gas phase cathode

A single liquid chamber microbial fuel cell (MFC) with a gas-collection compartment was continuously operated under electrically assisted conditions for hydrogen production. Graphite felt was used for anode construction, while the cathode was made of Pd/Pt coated Toray carbon fiber paper with a catalyst loading of 0.5 mg cm⁻². To achieve hydrogen production, the MFC was connected to a power supply and operated at voltages in a range of 0.5–1.3 V. Either acetate or glucose was used as a source of carbon. At an acetate load of 1.67 g (L_A d)⁻¹, the volumetric rate of hydrogen production reached 0.98 L_STP (L_A d)⁻¹ when a voltage of 1.16 V was applied. This corresponded to a hydrogen yield of 2 mol (mol-acetate)⁻¹ with a 50% conversion efficiency. Throughout the experiment, MFC efficiency was adversely affected by the metabolic activity of methanogenic microorganisms, which competed with exoelectrogenic microorganisms for the carbon source and consumed part of the hydrogen produced at the cathode.     

Hydrogen production with nickel powder cathode catalysts in microbial electrolysis cells

Although platinum is commonly used as catalyst on the cathode in microbial electrolysis cells (MEC), non-precious metal alternatives are needed to reduce costs. Cathodes were constructed using a nickel powder (0.5–1 μm) and their performance was compared to conventional electrodes containing Pt (0.002 μm) in MECs and electrochemical tests. The MEC performance in terms of coulombic efficiency, cathodic, hydrogen and energy recoveries were similar using Ni or Pt cathodes, although the maximum hydrogen production rate (Q) was slightly lower for Ni (Q = 1.2–1.3 m³ H₂/m³/d; 0.6 V applied) than Pt (1.6 m³ H₂/m³/d). Nickel dissolution was minimized by replacing medium in the reactor under anoxic conditions. The stability of the Ni particles was confirmed by examining the cathodes after 12 MEC cycles using scanning electron microscopy and linear sweep voltammetry. Analysis of the anodic communities in these reactors revealed dominant populations of Geobacter sulfurreduces and Pelobacter propionicus. These results demonstrate that nickel powder can be used as a viable alternative to Pt in MECs, allowing large scale production of cathodes with similar performance to systems that use precious metal catalysts.     

Ni foam cathode enables high volumetric H2 production in a microbial electrolysis cell

Valuable, “green” H₂ can be produced with a microbial electrolysis cell (MEC). To achieve a high volumetric production rate of high purity H₂, a continuous flow MEC with an anion exchange membrane, a flow through bioanode and a flow through Ni foam cathode was constructed. At an electrical energy input of 2.6 kWh m⁻³ H₂ (applied cell voltage: 1.00 V), this MEC was able to produce over 50 m³ H₂ m⁻³ MEC d⁻¹ (22.8 ± 0.1 A m⁻²). The MEC had a low cathode overpotential compared to an MEC with Pt-based cathode, because of the high specific surface area of Ni foam (128 m² m⁻² projected area). The MEC performance however, decreased during 32 days of operation due to an increase in anode and cathode overpotentials. Scaling likely caused the increase in anode overpotential, but it remained unclear what caused the increase in cathode overpotential.     

Electrodeposition of nickel particles on a gas diffusion cathode for hydrogen production in a microbial electrolysis cell

Gas diffusion cathodes with electrodeposited nickel (Ni) particles have been developed and tested for hydrogen production in a continuous flow microbial electrolysis cell (MEC). A high catalytic activity of electrodeposited Ni particles in such a MEC was obtained without a proton exchange membrane, i.e. under direct cathode exposure to anodic liquid. Co-electrodeposition of Pt and Ni particles did not improve any further hydrogen production. The maximum hydrogen production rate was 5.4 L/L_R/day, corresponding to Ni loads between 0.2 and 0.4 mg cm⁻². Continuous MEC operation demonstrated stable hydrogen production for over one month. Owing to the fast hydrogen transport through the cathodic gas diffusion layer, the loss of hydrogen production to methanogenic activity was minimal, generally with less than 5% methane in the off-gas. Overall, gas diffusion cathodes with electrodeposited Ni particles demonstrated excellent stability for hydrogen production compared to expensive Pt cathodes.     

Engineering model of a passive planar air breathing fuel cell cathode

The behavior of an air breathing fuel cell (ABFC) operated on dry-hydrogen in dead-ended mode is studied using theoretical analysis. A one-dimensional, non-isothermal, combined heat and mass transport model is developed that captures the coupling between water generation, oxygen consumption, self-heating and natural convection at the air breathing cathode. The model is validated against planar ABFC experimental measurements over a range of ambient temperatures. The model confirms the strong effect of self-heating on the water balance within passive ABFCs. Model analysis provides several conclusions: (1) thermal runaway caused by inadequate heat rejection predominantly limits ABFC performance. (2) The natural convection boundary layer represents a significant barrier to cathode mass and heat transfer. (3) Because the mass and heat transport numbers associated with natural convection are small, even slight forced convection dramatically affects cell behavior. (4) Performance optimization requires maximizing heat rejection while minimizing flooding. Decoupling the latter two phenomena is challenging due to the exponential relationship between water vapor saturation and temperature.