析气电极的传质过程研究

Studies on Mass Transfer at Gas-Evolving Electrode

采用指示离子法研究了析气电极的传质过程.在Ni/KOH体系中发现;lgδ和lgi的曲线斜率对于氢气泡为0.287,对于氧气泡则为0.583.用激光衍射法和激光多普勒法(LDA)获得的气泡大小及气泡上升速度数据检验了析气电极传质过程的流体动力模型及渗透模型.结果表明,因析气效应产生的传质强化现象的机理一般不是单一的.

Mass transfer at a gas evolving electrode was estimated by using a redox system of indicator ions. It was found that the absolute values of the slopes of 1gδ/1gi are 0. 287 for hydrogen and 0. 583 for oxygen generation in Ni/KOH system.The bubble size and velocity of bubble rise were measured by means of laser diffraction method and LDA. The data were used to examine the models of the mass transfer at gas evolving electrode (Hydrodynamic model and penetration model). It is concluded that the mechanism of enhance mass transfer from gas-evolving effects is not single.