MFC处理低浓度焦化废水的试验研究

使用单室空气阴极微生物电池处理焦化废水,以电压、电流密度、功率密度、COD去除率、p H为考察指标,分别用铂、四氧化三铁、二氧化锰作阴极,对比其去除效率和产电能力。实验结果表明,铂阴极的产电能力和废水处理效果最好,开路电压最大值达到521.469 m V。当电流密度为2.4 A/m2时功率密度达到最大值0.195 W/m2,COD去除率为82.9%;二氧化锰阴极MFC效果次之,四氧化三铁阴极MFC的效果最差。     

微生物燃料电池处理含铬废水并同步产电

以葡萄糖为阳极燃料、含铬废水为阴极液,碳毡为阳极、石墨板为阴极构建了双室微生物燃料电池,考察了阳极条件(底物浓度)及阴极条件(pH、初始六价铬浓度)对含铬废水的降解及MFC的产电性能的影响.结果表明低阴极液pH和高初始Cr(Ⅵ)浓度能改善MFC产电性能.当pH=2、初始六价铬浓度为177 mg/L、反应时间为10 h时,最大输出功率为108 mW/m~2,六价铬去除率为92.8%.阳极底物浓度对微生物燃料电池的性能也有影响.在微生物燃料电池中,阴极极化较小,表明该燃料电池有稳定的性能,微生物燃料电池对含铬废水的处理有应用潜力并能同步产电.     

酞菁铁-碳纳米管复合物为阴极催化剂的微生物燃料电池

以循环伏安法(CV)考察酞菁铁/碳纳米管氧还原(ORR)催化行为,并构建以磷酸缓冲溶液(PBS)和葡萄糖为阳极原料,酞菁铁/碳纳米管复合物为阴极氧气还原催化剂的双室型微生物燃料电池(MFCs)。结果表明:(1)在中性介质中,对氧还原的电催化性能要比商品化的铂碳催化剂还原电位正移了44 mV。(2)以大肠杆菌(E coli)为产电微生物,该MFC的最大输出功率密度为932.5 mW/m2,对应电流密度为2792.6 mA/m2,高于铂碳催化剂阴极的MFC。     

MFC-MEC耦合系统产电性能及处理含镉重金属废水的研究

以厌氧活性污泥为阳极菌种,乙酸钠为阳极底物,硫酸铜和重铬酸钾溶液为微生物燃料电池(MFC)阴极液,人工模拟含镉重金属废水为微生物电解池(MEC)阴极液,构建MFC-MEC耦合系统,利用MFC的产电驱动MEC运行,在不消耗外部能源的情况下,实现含镉重金属废水中Cd~(2+)的去除。实验研究了MFC反应器容积、MFC堆栈、MEC电极材料、MEC阴极液pH对MFC-MEC耦合系统电性能及含镉重金属废水处理效果的影响。结果表明:MFC反应容积的扩大可以提高其产电性能,但与此同时会造成MFC的内阻升高,随着MFC容积的增加,MEC中Cd~(2+)去除率逐渐增加,但同时MFC阴极Cr6+去除率逐渐下降;MFC堆栈可以提高工作组两端电压,串联时最大输出电压为1509 mV,Cd~(2+)去除率为69.3%;以钛板作为MEC电极时,微生物能有效附着在阳极表面,MFC阳极COD去除率为85%,MEC中Cd~(2+)去除率为51.5%;MEC阴极液pH在3～5时,有利于含镉重金属废水的处理,Cd~(2+)去除率80%以上。经XRD分析,MEC阴极还原产物为CdCO3。     

中空对称双阴极结构电池的高温抗氧化还原特性

研究了中空对称双阴极结构电池在燃料突然停止供应情况下的电化学行为及电池微观结构变化。结果表明:该结构电池在燃料气体停止供应后,阳极侧Ni被氧化0.44%(占支撑体总比例)时开路电压才开始下降,证实其抗氧化还原能力是传统超薄阳极支撑平板结构电池1.3～2.7倍,阳极结构中局部裂纹增多和严重团聚现象是造成电池结构破坏的主要原因。     

一体式无粘结剂rGO@MnO_2不锈钢纤维毡空气阴极的制备

利用化学及电化学方法将非贵金属催化剂石墨烯(rGO)和纳米MnO_2依次负载到三维多孔不锈钢纤维毡(Stainless steel fiber felt,SSFF)集电体上制备微生物燃料电池(Microbial fuel cell,MFC)空气阴极。在增大空气阴极活化面积的同时有效减小接触阻抗。通过物理和电化学方式测试表征其形貌、氧还原特性。在MFC中的运行结果表明,负载5 mL还原性氧化石墨烯再浸渍生长MnO_2的不锈钢纤维毡(rGO@MnO_2-SSFF)空气阴极的最大功率密度(524.34 mW/m~2)是不锈钢纤维毡阴极(58.21 mW/m~2)的9倍。经过复合催化剂rGO@MnO_2修饰之后的不锈钢纤维毡空气阴极可以应用于MFC并大幅改良SSFF空气阴极的氧还原催化性能。     

双极室微生物燃料电池处理不同阳极底物废水的产电研究

为了研究微生物燃料电池(MFC)在不同阳极底物废水条件下的产电效率和废水处理效果。分别以啤酒废水、糖蜜废水和啤酒-糖蜜混合废水作为阳极基质,含银电镀废水作为阴极电子受体,构建了双极室微生物燃料电池。结果表明,3组以糖蜜废水作为阳极基质的MFC产电量和COD去除率最高,啤酒废水次之,啤酒-糖蜜混合废水最低。糖蜜废水作为阳极基质的MFC最高电压和功率密度可达356 m V和36.21 m W/m~2,第3周期时COD去除率达到最高的69.29%,实验结束时阴极Ag~+的质量浓度最低至304 mg/L。不同阳极基质对MFC产电效率和废水处理效果有影响。     

MFC-MEC耦合系统产电性能及处理含镉重金属废水的研究

以厌氧活性污泥为阳极菌种,乙酸钠为阳极底物,硫酸铜和重铬酸钾溶液为微生物燃料电池（MFC）阴极液,人工模拟含镉重金属废水为微生物电解池（MEC）阴极液,构建MFC-MEC耦合系统,利用MFC的产电驱动MEC运行,在不消耗外部能源的情况下,实现含镉重金属废水中Cd²⁺的去除。实验研究了MFC反应器容积、MFC堆栈、MEC电极材料、MEC阴极液pH对MFC-MEC耦合系统电性能及含镉重金属废水处理效果的影响。结果表明：MFC反应容积的扩大可以提高其产电性能,但与此同时会造成MFC的内阻升高,随着MFC容积的增加,MEC中Cd²⁺去除率逐渐增加,但同时MFC阴极Cr⁶⁺去除率逐渐下降;MFC堆栈可以提高工作组两端电压,串联时最大输出电压为1509 mV,Cd²⁺去除率为69.3%;以钛板作为MEC电极时,微生物能有效附着在阳极表面,MFC阳极COD去除率为85%,MEC中Cd²⁺去除率为51.5%;MEC阴极液pH在3~5时,有利于含镉重金属废水的处理,Cd²⁺去除率80%以上。经XRD分析,MEC阴极还原产物为CdCO₃。     

外阻对双室微生物燃料电池性能的影响

实验分析了阴极硝化耦合阳极反硝化微生物燃料电池在不同外阻(10、100、500Ω和无穷大)下,电池的产电性能、阴极液和阳极液的电导率以及脱氮除碳能力的变化情况。结果表明,在低电阻下,输出的稳定电流较大,有机物降解速率较快,TN去除率较高。当外阻为10Ω时,输出的稳定电流是3.61 m A,COD的去除速率最快为10.33mg/(L·h),在运行160 h时TN去除率达到100%。MFC运行过程中,阳极溶液的电导率逐渐减小,阴极溶液的电导率逐渐增大。当外阻为10Ω时,阴阳极溶液的电导率差最大。CV扫描表明外阻对阳极生物膜氧化还原能力有影响,且低电阻下阳极形成的生物膜上产电活性菌的氧化能力越强。     

小球藻生物阴极型微生物燃料电池的基础特性

利用自行设计的阴极管状光生物反应器式微生物燃料电池(MFC)作为实验模型,考察了阴极室投加小球藻后不同光暗周期下电池的产电、阴极溶氧及阴极藻的生长情况. 结果表明,阴极投加小球藻后,电池产电性能明显提高,光暗间歇组最大功率密度为24.4 mW/m2,持续光照组最大功率密度为27.5 mW/m2. 阴极溶氧及电化学分析证实溶氧是影响电压变化的主要因素,持续光照组溶氧较稳定,但比光暗间歇组光照阶段溶氧水平低;MFC阴极室培养小球藻不会对其造成毒害,光暗间歇时小球藻生长较好. 运行小球藻生物阴极型MFC采用光暗间歇培养较好,并可适当延长光照时间.     

Cathodic activity of deep-sea manganese nodule in Leclanché-type test dry cell

The present study has examined the performance of the manganese nodule by incorporating it into the Leclanché cathode mix of D-size test cells.It has been found that, with the particular species collected from the Pacific Ocean, off-shore California, the value of O.C.V. was about 1.62 V, which is quite close to the value with naturally occurring manganese dioxide ores of battery grade. An intermittent discharge on a 4 Ω load, down to a cut-off voltage of 0.75 V, showed approximately half the service duration time obtained with E.M.D.However, when taking into consideration a low MnO₂ content of about 38% in the deep-sea ore tested and the various constituent elements present therein together, the exhibited performance as battery cathode active material was quite surprising.Digestion of the deep-sea nodule with hot sulfuric acid revealed that almost all the original content of MnO₂ was retained in the digested residue, while a 10–20 per cent portion of the accompanying elements was brought into the digesting solution. The “up-graded” MnO₂ product of nodule showed a better battery performance in accordance with the increase in MnO₂ content.These results suggest that the MnO₂ phase present in the manganese nodule might be quite similar to the one possessed by the cathode active γ-MnO₂ species, and that the MnO₂ crystalline net work formation mechanisms involved in “autoclave” of the deep sea might have something in common with the anode oxidation product synthesized by electrolysis.     

Influence of NO3 and SO4 on power generation from microbial fuel cells

Potential competition in terms of electron transfer from bacteria to electron acceptors such as nitrate (NO₃) and sulfate (SO₄) or the anode of a microbial fuel cell (MFC) was investigated to determine how alternative electron acceptors would influence power generation in an MFC. The cell voltage was not initially affected when these electron acceptors were introduced into the MFCs. However, the presence of NO₃ decreased the CE of the MFC compared to the injections of SO₄ or control salt (sodium chloride). This suggests that the growth of nitrate-reducing bacteria independent of the microbial populations on the MFC anode were not utilizing the anode as an electron acceptor, rather, they were consuming organic carbon in the anodic chamber of the MFC, resulting in a decrease of the CE of this MFC with no immediate impact on power output. This suggests that the bacterial consortium in the nitrate-MFC still preferred the anode over nitrate as the electron acceptor, although the theoretical reduction voltage of nitrate (+0.74 V) is higher than the reduction voltage in an MFC air cathode (as high as +0.425). These results are useful when considering whether MFC technology can be applied in situ to enhance biodegradation of organic contaminants in the presence of alternative electron acceptors.     

两室气体互通对光合微生物燃料电池性能的影响

以斜生栅藻生长产生氧为电子受体的光合微生物燃料电池(PMFC)和外加CO2光合微生物燃料电池(AC-PMFC)联合构建成微生物碳捕获电池(MCC).研究MCC在不同运行条件下的产电性能及影响因素.测量MCC,PMFC和AC-PMFC三种系统中的电压、溶解氧和pH.结果表明,产电压趋势与所有系统中的藻类阴极的氧浓度相关,...     

水系锌离子电池的研究和产业化进展

水系锌离子电池是一种新型的绿色电池体系,不仅具有廉价、安全、环保的特点,还具有较高的功率密度,在储能等诸多领域具有很好的应用价值和发展前景。综述了水系锌离子电池正极材料、锌负极和电解液的基础研究和产业化进展,包括二氧化锰正极材料开发、电池器件制备和应用。总结了目前水系锌离子电池产业化的可行性和难点。提出了亟需解决的3个关键问题：首先,水系锌离子电池体系的反应机理仍需深入研究以指导高性能正负极材料开发;其次,高纯度二氧化锰正极材料、耐腐蚀集流体、耐刺穿隔膜等产业链关键环节缺失制约了商业化电池的开发;最后,从实验室到中试及规模化放大过程中电池性能明显降低,系统的电极制备和电池组装工艺仍需系统化研究。     

樊立萍1,*,温越霄1,2

为提高微生物燃料电池(MFC)的废水处理效果和发电性能,制备了一种海藻酸钠-聚季铵盐11/碳毡(SA-PQ-11/CF)阳极,分别以制药废水和糖蜜废水为阳极液,以碳毡为阴极,构建微生物燃料电池(MFC)实验系统,通过扫描电子显微镜(SEM)、电化学阻抗谱(EIS)、循环伏安特性(CV)、化学需氧量(COD)对其性能进行表征。结果显示,SA-PQ-11/CF阳极具有较大的比表面积,MFC的溶液电阻和电荷转移电阻也得到明显降低。阳极液为制药废水时,采用SA-PQ-11/CF阳极的MFC的稳态输出电压和COD去除率分别约为0.22 V和62%,较常规碳毡阳极时分别提高了100%和130%。阳极液为糖蜜废水时,采用SA-PQ-11/CF阳极的MFC的稳态输出电压和COD去除率分别为0.15 V和43%,分别较采用常规碳毡阳极时提高了275%和95%。基于SA-PQ-11的阳极改性能够有效提高MFC的废水处理效果和产电能力。     

An environmentally friendly water-activated manganese dioxide battery

In this work an environmentally friendly water-activated battery was developed and investigated. The anode material was a magnesium alloy; the cathode consisted of manganese dioxide, potassium chloride and graphite. Battery characteristics were tested at room temperature and additionally in an atmospheric simulation chamber because water-activated batteries are mostly used in meteorological radiosondes. Voltage losses inside the battery were measured using a miniaturized reference electrode, and heat evolution of the battery was studied calorimetrically. The main source of voltage losses and heat was found to be the magnesium anode. Compared to the traditional Mg/CuCl batteries, there was little difference in voltage and capacity, but a significant difference in the environmental impact, as the Mg/MnO₂ battery does not contain any heavy metal salts.     

Enhanced discharge voltage by CuO and RuO2 modification of ferrate(VI) cathode in alkaline super-iron/TiB2 batteries

The K₂FeO₄/TiB₂ battery has a significant advantage of battery capacity due to their multi-electron discharge reaction both of the cathode K₂FeO₄ (3e⁻) and the anode TiB₂ (6e⁻). However, the more positive reduction potential of TiB₂ anode results in a lower discharge voltage plateau of K₂FeO₄/TiB₂ battery, compared with the K₂FeO₄/Zn battery. The simple modification of Fe(VI) cathode with CuO additive was used to improve the cathode reduction kinetics and decrease the polarization potential in the discharge process. Another electrocatalysis media RuO₂ with excellent electric conductivity is used as additive in K₂FeO₄ cathode to demonstrate which effect is more important for the discharge voltage plateau, electrocatalysis or electron conductivity of additives. The results show that the 5% CuO additive modified K₂FeO₄/TiB₂ battery exhibits an enhanced discharge voltage plateau (1.5 V) and a higher cathode specific capacity (327 mAh/g). The advanced discharge voltage plateau can be due to the electrocatalysis of additives on the electrochemical reduction kinetics of Fe(VI) cathode in the whole discharge process, rather than the good electronic conductivity of additives.     

Generation behavior of elctricity in a microbial fuel cell

Electricity generation using a microbial fuel cell (MFC) was investigated with acetate as the fuel and Geobacter sulfurreducens as the biocatalyst on the anode electrode. The voltage and power density behaviors at various external resistances were observed, as were the coulombic efficiency and energy recovery behaviors at various acetate concentrations. A high voltage production was obtained when the pH in the cathode chamber was maintained in the range of 7–8, which is similar to that used in other MFC studies. After 72 hours of operation, the voltage production was decreased by 11.5% with 30 mM tris-HCl and by 33.7% with 10 mM tris-HCl.     

Current efficiency studies for graphite and SnO2-based anodes for the electro-deoxidation of metal oxides

Studies were performed investigating the electrochemical reduction of chromium oxide (Cr₂O₃) by electro-deoxidation by utilising either a graphite anode or a tin oxide (SnO₂) based anode. Potentiostatic electrolysis was performed at 3.0 V for both a graphite and for a SnO₂-based anode, and also 2.0 V for a graphite anode. The cathode reduction purity, anode mass change, anode potential relative to a glassy carbon pseudo-reference and current efficiency were measured and compared. The key observations are that substituting a SnO₂-based anode for a graphite anode led to greater current efficiencies for electro-deoxidation. This was attributed to the lack of contamination of the melt by carbon and the lower cathode potential due to the higher anodic potential when using tin oxide based anodes for the same applied voltage. The current efficiency was also found to decrease with both anode materials when higher anode surface areas or lower current densities were used. Again this was attributed to a decrease in anodic potentials and a corresponding increase in the cathodic potential resulting in a greater number of parasitic reactions occurring at the cathode.