铅电解废液除锌工艺研究

Study on Zinc Extraction from Crude Lead Electrolyte

采用"硫酸沉铅—中和—P204萃取提锌—硫酸反萃"工艺净化处理铅电解废液,重点考察P204煤油体系萃取提锌、硫酸反萃及萃取反萃循环过程。结果表明,按照相比1∶1.5单级萃取的萃取率可达99%左右,3mol/L硫酸单级反萃锌反萃率基本可达100%。9次萃取反萃循环试验后,锌富集浓度可达33g/L,负载有机相锌反萃率达到99.49%,锌直收率可达88.24%。

The process of lead precipitating with H2SO4, neutralization, zinc extraction with P204, stripping with HzSO4 was proposed for lead electrolyte purification. The process of zinc extraction with P204＋ kerosene system, back extraction with H2SO4 and cyclic process of extraction-back extraction were investigated emphatically. The results show that the single stage extraction rate is about 99% on condition of O/A=I/1.5. Back extraction rate of zinc single stage is about 100% with 3 mol/L HzSO4. The enriched zinc concentration is 33 g/L, zinc stripping rate reaches 99.49%, and zinc total recovery rate is about 88.24% after 9 times extraction-back extraction cyclic process.