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51.
我国金属阳极隔膜法烧碱发展现状与对策 总被引:1,自引:0,他引:1
详细介绍了我国氯碱工业采用金属阳极隔膜法制烧碱的现状及与世界先进水平的差距。提出了包括大力进行以节能为重点的技术改造;调整烧碱产品规格;彻底淘汰和转换石墨阳极隔膜法;推广先进的扩张金属阳极隔膜电解技术以及结合我国国情有计划地发展离子膜法制烧碱技术等改造措施及预期效果。 相似文献
52.
Three types of anode, Pb–Sb, Pb–Ca–Sn and Pb–Co3O4, for copper electrowinning were investigated. The corrosion resistance, as evaluated by cyclic voltammetric (CV) measurements was higher for Pb–Co3O4 than for Pb–Sb and Pb–Ca–Sn. During prolonged electrowinning under galvanostatic conditions, the anodic reaction on the Pb–Co3O4 anode was depolarized by 0.053 V as compared to Pb–Sb, and by 0.106 V with respect to Pb–Ca–Sn. The composition and structure of the anodic layer were determined by XPS, X-ray and SEM analyses. The surface layer on the three anodes examined was composed mainly of PbSO4, -PbO2 and -PbO2. Different structure of the surface layer was observed: loose and highly spread coral-like structure in the case of Pb–Sb; fibrous structure in the case of Pb–Ca–Sn and dense, fine-grained structure in the case of Pb–Co3O4. 相似文献
53.
A. Sivashanmugam T. Prem kumar N. G. Renganathan S. Gopukumar 《Journal of Applied Electrochemistry》2004,34(11):1135-1139
In this work, we describe an evaluation of an Mg–Li alloy (Li: 13 wt %) for possible use in magnesium primary reserve batteries. Higher OCP for the Mg–Li alloy have been observed in 2 M MgCl2 and MgBr2 electrolyte. The corrosion rate of the Mg–Li alloy is found to be in the order: MgCl2 < Mg(COOCH3)2 < MgSO4 < MgBr2 < Mg(ClO4)2. Mg–Li alloys exhibit higher (81%) anodic efficiencies even when the current density is increased to 8.6 mA cm –2. It has been observed that Mg–Li/MgCl2/CuO cells offer higher operating voltage and capacity than those with the conventionally used Mg–Al alloy. 相似文献
54.
55.
The membrane electrode assembly (MEA) studied was constituted with a gas diffusion electrode (E-TEK) impregnated with Nafion® solution which was assembled with a Nafion® 117 cation exchange membrane under heat and pressure. The MEA was used as anode in a membrane electrolysis (ME) cell with the objective to regenerate HCl and NaOH from NaCl. Current efficiency for hydrogen oxidation was determined and its value is 100%, which indicates that the only reaction occurring at the anode is the oxidation of hydrogen. Current-potential curves, recorded in different conditions, showed a linear variation in the range 0-3000 A m−2 when hydrochloric acid concentration is below 2 mol dm−3. In this case, the overvoltage was shown to be mainly due to the ohmic drop in the membrane and in the layer where Nafion® impregnation was performed. MEA overvoltage necessary to reach 3000 A m−2 current density was about 0.12 V. For high HCl concentration (6-8 mol dm−3), the MEA overvoltage increased sharply with current density due to the adsorption of chloride anions on platinum catalyst. 相似文献
56.
何玲平 《上海电力学院学报》2010,(4)
基于楔条形阳极位置灵敏探测器的成像原理和二维傅里叶变换理论,提出了一种建立该类探测器成像模型的方法,进而模拟了探测器的成像效果,仿真了成像的几何非线性,仿真图像与实际图像基本符合。仿真结果表明:在阳极面板半径多出微通道板半径2P(P为阳极周期宽度)和电子云分布半宽度D为1.3P时,该类探测器的成像线性良好;电子云过小即D
5P时,电子云超出楔条形阳极工作区域,成像边缘扭曲十分明显。 相似文献
57.
介绍了直接甲酸燃料电池(DFAFC)阳极电催化机理,以及Pt基、Pd基附载型和非附载型阳极催化剂的发展状况,分析了金属合金d-带能级移动和金属表面偏析对直接甲酸燃料电池催化活性的影响,对筛选阳极催化剂合金材料具有一定的指导作用. 相似文献
58.
同步产电及废水处理AFB-MFC电极研究 总被引:2,自引:0,他引:2
为了考察电极因素对微生物燃料电池产电及废水处理性能的影响,设计了一种新型厌氧流化床微生物燃料电池(AFB-MFC).研究了不同阴极电极材料,阴极与阳极面积以及阴极底边与阴极室底部距离对AFB-MFC产电及废水处理性能的影响.所有实验在阴极室曝气量为16~24 L/h、回流量为10.7 L/h、进水流量为0.6 L/h、外电阻为250 Ω以及进水COD浓度为3000.98~3789.44 mg/L下进行.结果表明,在尺寸大小均为15.0 cm×3.5cm的碳纸、铜板、铝板、镀锌铁板及铁板中,使用碳纸作阴极电极时AFB-MFC产电性能最好;阴极底边与阴极室底部的最佳距离为17.3~20.3 cm;使用面积为308.8、232.0、160.0和76.8 cm2的碳纸作阳极电极及面积为241.5、210.0、175.0和105.0 cm2碳纸作阴极时,阳极及阴极最佳面积分别为160.0和210.0 cm2.AFB-MFC系统最佳运行条件下COD的去除率维持在约80.00%.放大型AFB-MFC系统有利于今后工程实际应用. 相似文献
59.
Jernej Drofenik Robert Dominko Mogens Mogensen Stane Pejovnik 《Electrochimica acta》2003,48(7):883-889
Four types of cellulose, in particular carboxy methyl cellulose (CMC), are tested as potential binding materials in graphitic anodes for lithium ion batteries. It is shown that a minimum content of a cellulose which gives acceptable anode properties (reversible capacity>300 mA h g−1 during the first 10 cycles, irreversible loss<20%) is about 2 wt.%, which is less than in the case of conventional polymeric binders (5-10 wt.%). Kinetics of insertion-deinsertion and passivation processes seem not to be affected by the presence of cellulose. Explanation for the electrode failure at cellulose contents lower than 1 wt.% is given based on X-ray diffraction and microscopy investigations. Finally, the structure (distribution) of cellulose in the composite anode material is discussed and (indirectly) checked with a series of experiments. Most results are compared with the corresponding results obtained either with gelatin or conventional polymeric binders or both. 相似文献
60.
In order to study the anodic behavior and microstmctures of A1/Pb-Ag-Co anode during zinc electrowinning, by means of potentiodynamic investigations, scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses, the mechanism of the anodic processes playing on the surface of A1/Pb-0.8%Ag and A1/Pb-0.75%Ag-0.03%Co anodes prepared by electro-deposition from methyl sulfonic acid bath for zinc electrowinning from model sulphate electrolytes have been measured. On the basis of the cyclic voltammograms obtained, information about the corrosion rate of the composite in PbO2 region has been concluded. The microstructures were also observed by means of SEM and XRD which showed Pb-0.75%Ag-0.03%Co alloy composite coating has uniform and chaotic orientation tetragonal symmetry crystallites of PbSO4, but Pb-0.8%Ag alloy composite coating has well-organized orientation crystallites of PbSO4 concentrated in the certain zones after 24 h of anodic polarization. It is important that Al/Pb-0.75%Ag-0.03%Co anode oxide film consists of non-conductive dense MnO2 and PbSO4 and a, fl-PbO2 penetrated into which, in fact, are the active centers of the oxygen evolution after 24 h of anodic polarization. 相似文献