助溶剂在废铅膏湿法回收铅工艺中的应用

Application of cosolvent in the hydrometallurgical process of recovering lead from spent lead paste

在草酸–草酸钠湿法浸取废铅膏回收铅工艺中引入助溶剂——聚天冬氨酸(PASP),以促进PbSO_4溶解转化和PbO_2还原,进而研究PASP对废铅膏转化以及回收制得的铅氧化物电化学性能的影响。结果表明:当PASP与废铅膏的质量比为1∶4时,铅的回收率达99%以上,脱硫率达99.9%以上;回收制得的铅氧化物正极放电比容量高达107.6 m Ah·g^(-1),活性物质利用率为44.8%,循环50次后容量保持率仍高于90%。

Polyaspartic acid was used as a cosolvent to promote the conversion of PbSO4 and reduction of PbO2 in the oxalate-sodium oxalate wet leaching process of recovering lead from spent lead paste. Further, the influences of the addition of PASP on the conversion of spent lead paste and electrochemical performance of prepared lead powders were studied. The results showed that not only lead recovery and desulfurization rate were higher than 99 % and 99.9 % respectively, but also the discharge capacity of the prepared lead oxide reached up to 107.6 mAh/g, corresponding to the utilization up to 44.8 % of positive electrode active materials and capacity retention rate above 90 % after 50 cycles when the mass ratio of PASP and spent lead paste was 1/4.