The acid leaching of spent zinc containing targets resources recycling technology

This study focuses on the transparent conductive zinc oxide target: zinc sulfide (ZnS) and gallium zinc oxide (GZO). These two kinds of zinc film targets, conduct resource recycling as zinc sulfide and zinc carbonate powder and the targets contains silver, gallium, indium and other rare metals that we try to make this recycling process effectively. We peeled off the coating layer of the targets and analyzed it. We found that the silver and gallium are in the structure of the targets while the indium is in the coating layer. We used different concentration of nitric acid to leach the rare metals in the targets. Then, we tried different solid-liquid ratio to leach the rare metals. With different conditions, we got different data of leaching amount. After leaching, we will choose solvent extraction to enrich the rare metals and recycle. By using the right condition, we can get 90% overall fraction recovery with more than 98% purity of silver, gallium and indium. After the recovery of rare metal, zinc metal can also be recovered effectively. Therefore, this makes zinc metal and precious metal recovery efficiency of the substantial increase. Moreover, this recovery method has less impact on the environment.