Modeling of Aluminum Electrowinning in Ionic Liquid Electrolytes
Modeling of Aluminum Electrowinning in Ionic Liquid Electrolytes
复制标题
离子液体电解质中电解沉积铝的建模
DOI：
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
R. Reddy
中科院分区：
文献类型：
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作者：
Mingming Zhang;R. Reddy
建立了离子液体低温电积铝间歇式反应器的三维数学模型。该模型通过结合参与离子的质量传递、扩散层内的均匀化学反应以及相关的电化学动力学来描述沉积过程。对工艺参数、电流和电位分布、物质浓度、流体流动分布和电极间距进行了评估，以获得最佳反应器性能。结果表明，电极间距对电解液流动和电流密度分布有显著影响。平行电极配置（与电解质入口一致）改善了对流，使电流密度分布均匀，电解质流体流动均匀。然而，对于这种电极结构，电活性物质在电极之间的分布是最有利的。垂直的电极结构导致电解质域内的流体流动更加不均匀，并且有可能导致不均匀的沉积。铝电积实验采用间歇式反应器，温度为80℃，电解液流速为5 ~ 20 ml/min，电池电压为3 ~ 3.5 V。模型与批量电积铝实验结果吻合较好。
A 3-D mathematical model was developed for the batch reactor of low temperature aluminum electrowinning using ionic liquid electrolytes. This model describes the deposition process by incorporating the mass transport of participating ionic species, homogeneous chemical reactions within the diffusion layer, and the associated electrochemical kinetics. Processing parameters, current and potential distribution, species concentration, fluid flow distribution, and electrode spacing were evaluated for the optimal reactor performance. The results indicated that the electrode spacing significantly affects the electrolyte fluid flow and current density distribution. The parallel electrode configuration (in line with electrolyte inlet) improved the convection and resulted in uniform current density distribution and electrolyte fluid flow. However, for this electrode configuration, electroactive species distribution was most favorable between the electrodes. Perpendicular configuration of electrodes resulted in a more non-uniform fluid flow within electrolyte domain, and it has a potential to cause non-uniform deposits. Aluminum electrowinning experiments were conducted using batch reactor at 80 °C, electrolyte flow rate of 5–20 ml/min, and applied cell voltage of 3–3.5 V. Good agreement was obtained between the model and the batch aluminum electrowinning experimental results.