title: Recovering lead from cathode ray tube funnel glass by mechano-chemical extraction in alkaline solution.
abstract: This study evaluates the efficiency of lead (Pb) extraction from cathode ray tube (CRT) funnel glass in strongly alkaline solution using mechanical activation in a ball mill as the chemical breakage and defects formed in the inner structures will contribute to the easy dissolution of the activated Pb glass. The combination of mechanical activation and a chemical leaching process in a single operation (mechano-chemical leaching) is more effective than the mechanical activation and subsequent chemical leaching. More than 97% of Pb in the CRT funnel glass can be extracted with a stirring ball mill leaching process in 5 M sodium hydroxide at 70°C. The diameter of the stainless steel balls as the activation medium is 5 mm; the mass ratio of ball to raw materials is 25:1. Pb powder with a purity of 97% can be obtained by electrowinning from the leaching solution. The Pb-depleted solution can be recycled into the leaching step. After Pb is removed, the solid leaching residues can be used for preparation of foam glass. Thus, a novel hydrometallurgical process for recovering Pb from CRT funnel glass in alkaline solution is proposed.
authors.affiliation: School of Urban Development and Environmental Engineering, Shanghai Second Polytechnic University, Shanghai, People's Republic of China. chenglongzh@sina.com
authors.forename: Chenglong
authors.initials: C
authors.lastname: Zhang
authors.forename: Jingwei
authors.initials: J
authors.lastname: Wang
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Bai
authors.forename: Jie
authors.initials: J
authors.lastname: Guan
authors.forename: Wenjie
authors.initials: W
authors.lastname: Wu
authors.forename: Cuixiang
authors.initials: C
authors.lastname: Guo
mesh_terms: D055984:Cathode Ray Tube; D007854:Lead / Q000302:isolation & purification*; D008855:Microscopy, Electron, Scanning
chemical_list: D007854:Lead
keywords: Cathode ray tube (CRT) funnel glass; alkaline leaching; electrowinning; lead; mechano-chemical leaching