二元混合铜颗粒流化床电极的研究

Investigation on the Fluidized Bed Electrode with Binary Copper Particle Mixtures

以两种不同粒径的铜颗粒构成的二元混合颗粒为阴极颗粒,浓度低于1 g/L的硫酸铜溶液为电解液,在横截面为50 mm×15 mm的流化床电极中探讨床层膨胀率、混合颗粒粒径比及质量比对铜沉积速率、电流效率的影响。研究结果表明,二元混合颗粒可以显著的强化传质过程,提高铜的沉积速率;混合颗粒床层膨胀率、粒径比和质量比对铜沉积速率、电流效率有重要影响,都存在一最佳值,即膨胀率约20%、大颗粒质量分率约75%、粒径比为2.09。在此条件下沉积速率最大,为1.6 g/(m2.h),约为单粒径颗粒床层的2.5倍,电流效率最高,达到约88%。

Electrolyte with low concentration of copper sulphate was processed in a fluidized bed electrode with cross section measuring 50 mm×15 mm. A mixture of copper particles with two different sizes was put into the bed acting as the particle electrode. The experiment was focused on the investigation of the influence on the deposition rate and current efficiency by bed expansion, particle diameter ratio and the mass fraction of the bigger particle in the mixture. The experimental results showed that the mixture of copper particles with two different sizes could enhance the mass transfer process remarkably. The copper deposition rate and the current efficiency were influenced evidently by all the three factors above. The optimum values for expansion ratio, the mass fraction of bigger particle in the mixture and the particle diameter ratio were 20%, 75% and 2. 09 respectively. The maximum deposition rate was 1. 6 g/（m^2· h） which was raised by 1. 5 times in comparison with conventional fluidized bed electrode filled with uniform particles and the highest current efficiency was about 88% at the optimum values.