旋流电积技术在碲电积工艺中的试验探究

Experimental research on application of swirl electrowinning technology in tellurium electrowinning process

旋流电积技术可以实现电解液的高速循环流动,具有电解液终点浓度要求低、直收率高、高电流密度、高电流效率、产品回收率高的特点。本文采用二氧化碲与氢氧化钠配制亚碲酸钠碱性溶液作为电解液,考察不同碲初始浓度、氢氧化钠浓度、循环流量及电流密度对旋流电积试验的影响,得到最佳旋流电积参数:电解液初始浓度100 g/L,氢氧化钠浓度100 g/L,循环流量300 L/h,电流密度100 A/m2。在使用不锈钢作为阴极,最优电积参数下电积6 h,阴极产品经草酸煮洗后可得到纯度为99.939%的碲,生产参数:电流效率96.12%,平均槽电压1.96 V,电能消耗1 713 k W·h/t。

The swirl electrowinning technology can make the electrolyte flow at a high speed,and has the advantages of low electrolyte end-point concentration,high direct yield,high current density,high current efficiency,and high product recovery rate. In this paper,tellurium dioxide and sodium hydroxide are used to prepare an alkaline solution of sodium tellurite as the electrolyte to investigate the influence of different initial tellurium concentration,sodium hydroxide concentration,circulating flow rate and current density on the swirl electrowinning test,and get the best electrowinning parameters,initial concentration of electrolyte 100 g/L,concentration of sodium hydroxide100 g/L,circulation flow 300 L/h,and current density 100 A/m2. When stainless steel is used as the cathode,and the optimal electrowinning parameters are used for 6 hours,the cathode product can obtain tellurium with a purity of 99. 939% after being boiled and washed with oxalic acid. The production parameters are as follows,current efficiency 96. 12%,average cell voltage 1. 96 V,power consumption 1 713 kW·h/t.