A Review on Lead Extraction from Ore and Spent Lead Paste by Hydrometallurgical Processes.

Lead ore/concentrate and spent lead paste are main resources for lead production currently. Though pyrometallurgical processes are mostly applied in industry, they usually suffer from the potential pollution of lead particulates and sulfur oxides released to the environment. More attention has been paid to hydrometallurgical processes for lead extraction from various lead resources especially the spent lead paste. The alkaline leaching-crystallization process has high efficiency in impurity removal. However, they usually are relatively expensive, and corrosion from hot concentrated alkali solution is inevitable. The process using organic reagent leaching followed by calcination is not effective in controlling the impurities in lead oxide products. Though the current hydrometallurgical processes generally have problems of high cost, complicated process, and difficulty in disposing of waste liquid, researchers believe that the hydrometallurgical methods may find their way in practical application because of their relatively low pollution, flexible flowsheet, and versatility in final products and, more important, the challenge to healthy and sustainable development for the lead industry. All these hydrometallurgical processes included in this review offer valuable insights for researchers developing novel hydrometallurgical processes, especially those environment-friendly processes with broad economic potentials in the context of carbon neutrality and carbon peak. [ABSTRACT FROM AUTHOR]