Experimental study on leaching and dechlorination of secondary zinc oxide soot
The main component of secondary zinc oxide soot is zinc oxide,which is easy to leach and has a high zinc recovery rate.However,with the increase of elements such as fluorine and chlorine,it has a significant impact on the later zinc leaching and electrowinning process control.Efficient removal of fluorine and chlorine from zinc oxide ash has become a key focus of research in the zinc smelting industry.A single factor experiment was conducted to investigate the effects of factors such as liquid-solid ratio,leaching temperature,leaching time,and pH value on the removal rate of Cl and the loss rate of Zn in secondary zinc oxide ash produced by lead smelting,using water and sodium carbonate as leaching agents.The process optimization parameters were determined to be:alkaline leaching with sodium carbonate,liquid-solid ratio of 8∶1,leaching temperature of 45 ℃,leaching time of 100 minutes,and pH value of 11.0.Under these optimization parameters,the chlorine removal rate reached 87.43%,the zinc loss rate is 0.5%.