还原挥发氧化锌烟尘中有价金属分离工艺研究

Research on process of separating valuable metals from zinc oxide fly ash

针对含多种有价金属的还原挥发氧化锌烟尘,提出一条全湿法分离烟尘中有价金属的工艺路线。首先采用加双氧水氧化稀硫酸浸出,经过滤和洗涤,分别获得含硫酸锌、硫酸铟浸出液和含铅、铋浸出渣,实现锌、铟与铅、铋分离;对含硫酸锌和硫酸铟浸出液采用P204萃取,实现锌与铟的分离;对含铅、铋浸出渣采用碳酸氢铵转化生成碳酸铅,加硝酸溶解,实现铅与铋的分离。该工艺不仅可有效分离烟尘中的有价金属,而且获得的硫酸锌、硫酸铟、硝酸铅、富铋渣可用于生产其他化工产品,为氧化锌烟尘高效综合利用提供了一条新的途径。

On the basis of zinc oxide fly ash bearing multiple valuable metals,a whole hydrometallurgical technique for separation valuable metals from zinc oxide fly ash has been put forward.First,zinc oxide fly ash was leached by adding hydrogen peroxide and sulfuric acid,leaching liquor bearing zinc sulfate and indium sulfate and leaching residue bearing Pb and Bi were obtained by filtration and washing,and realized the separation of Zn and In from Pb and Bi.Leaching liquor realized the separation of Zn from In by P204 extraction.Lead sulfate in leaching residue was converted into lead carbonate by adding ammonium bicarbonate,and then lead carbonate reacted with added nitric acid,which realized the separation of Pb from Bi.On the one hand,the process realized the separation valuable metals from zinc oxide fly ash,on the other hand,zinc sulfate,indium sulfate,lead nitrate,and rich bismuth residue during the separation were used for producing the other chemical products.This process has supplied a new process for making comprehensive use of zinc oxide fly ash.