氯盐体系锡隔膜电沉积仿真模拟

Simulation of tin membrane electrodeposition in chloride system

采用COMSOL多场耦合计算机仿真软件对氯盐体系锡隔膜电沉积进行了仿真模拟,研究锡隔膜电积时电解槽内离子浓度、流体密度、流体速度、电流密度等的分布特征及其随时间的变化规律。结果表明:锡隔膜电积时槽内离子浓度分布受到入口流速、电流密度、电积时间、槽内离子互相作用的影响而发生变化。增加进液速度及降低HCl浓度有利于提高电解液平均密度及阴极表面Sn^2+的最低浓度。电积时极板边缘发生离子对流,顶部对流速度高于边缘处对流速度,且流体密度梯度影响离子对流方式。极板周围电流密度分布呈非均匀分布,在电极边缘发生电流偏转。增加电流密度能降低阴极表面Sn^2+最低浓度及流体的平均密度,同时也将增加阴极表面流体的平均流速,并使得阴极产物厚度不均匀。

ACOMSOL multi-field coupled computer simulation software was used to simulate tin membrane electrodeposition in the chloride system,and the distribution characteristics of ion concentration,fluid density,fluid velocity,current density and other physical quantities in the cell were studied,as well as the variation law with time.The results show that the ion concentration distribution is affected by the inlet velocity,current density,reaction time and the interaction between the ions.The way of increasing the inlet velocity and decreasing the HCl concentration can improve the average density of electrolyte and the lowest concentration of Sn^2+ on the cathode surface.The velocity of the top convection is higher than that of the edge,and the fluid density gradient affects the ion convection mode.The current density distribution around the plate is non-uniform and current deflection occurs at the edge of the electrode.The increase of current density can reduce the lowest concentration of Sn^2+ on the cathode surface and the average density of the fluid.It also increases the average flow rate of the fluid on the cathode surface and makes the thickness of the cathode products uneven.