银电解液中钯的定向分离试验研究

针对现阶段银电解工艺的电解液净化方式中存在的不足, 结合丁二酮肟对钯的良好选择分离性, 对银电解液中的钯开展了吸附分离研究, 验证了丁二酮肟分离银电解液中钯的可行性。开展了60 ℃、反应时间30 min下, 不同酸度补加量、丁二酮肟加入量的条件试验, 确定了最优工艺控制参数为:硝酸补加量60 mL/L、丁二酮肟加入量为理论量的2倍, 在该工艺条件下, 钯的分离率可以达到83%, 铂、铋分离率分别为18.75%和6.3%, 铜、银无分离。分离后沉淀渣含钯30%、含铂0.57%, 可以直接用于后续的铂钯精炼提纯。

Experimental Study on Directional Separation of Palladium from Silver Electrolyte

In view of the shortcomings in the current electrolyte purification in silver electrolysis process, the adsorption and separation experiments were conducted for the palladium in silver electrolyte by taking advantage of the selective separation of palladium by dimethylglyoxime, so as to verify the feasibility of palladium separated from electrolyte with dimethylglyoxime. Based on the conditional tests at a temperature of 60 ℃ for 30 min by adding different amount of dimethylglyoxime, as well as adding different amount of nitric acid for adjusting the acidity of solution, it was finally found that the test with the optimal processing parameters including addition of nitric acid at an amount of 60 mL/L, addition of dimethylglyoxime twice the theoretical amount, resulted in the separation rate of palladium reaching 83% and the separation rates of platinum and bismuth at 18.75% and 6.3%, respectively, without separation of copper and silver. The precipitated slag after separation process contained 30% palladium and 0.57% platinum, which could be directly used for subsequent refining and purification of platinum and palladium.