title: Recovery of lead from lead paste in spent lead acid battery by hydrometallurgical desulfurization and vacuum thermal reduction.
abstract: Lead sulfate, lead oxides and lead metal are the main component of lead paste in spent lead acid battery. When lead sulfate was desulfurized and transformed into lead carbonate by sodium carbonate, lead metal and lead oxides remained unchanged. Lead carbonate is easily decomposed to lead oxide and carbon dioxide under high temperature. Namely, vacuum thermal process is the reduction reaction of lead oxides. A compatible environmental process consisted of hydrometallurgical desulfurization and vacuum thermal reduction to recycle lead was investigated in this research. Lead paste was firstly desulfurized with sodium carbonate, by which, the content of sulfur declined from 7.87% to 0.26%. Then, the desulfurized lead paste was reduced by charcoal under vacuum. Under the optimized reaction conditions, i.e., vacuum thermal reduction at temperature 850°C under 20 Pa for 45 min, a 22.11×10(-2) g cm(-2) min(-1) reduction rate, and a 98.13% direct recovery ratio of fine lead (99.77%) had been achieved, respectively.
authors.affiliation: Key Laboratory of Resources Chemistry of Nonferrous Metals, Central South University, Ministry of Education of the People's Republic of China, China.
authors.forename: Yunjian
authors.initials: Y
authors.lastname: Ma
authors.affiliation: Key Laboratory of Resources Chemistry of Nonferrous Metals, Central South University, Ministry of Education of the People's Republic of China, China. Electronic address: qiuwhs@sohu.com.
authors.forename: Keqiang
authors.initials: K
authors.lastname: Qiu
mesh_terms: D001272:Atmosphere; D002245:Carbon Dioxide / Q000737:chemistry; D002254:Carbonates / Q000737:chemistry; D011211:Electric Power Supplies; D004867:Equipment Design; D007854:Lead / Q000737:chemistry*; D008669:Metallurgy; D010087:Oxides / Q000737:chemistry; D011312:Pressure; D059027:Recycling; D013455:Sulfur / Q000737:chemistry*; D013458:Sulfur Dioxide / Q000737:chemistry*; D013696:Temperature; D013816:Thermodynamics; D014618:Vacuum; D014961:X-Ray Diffraction
chemical_list: D002254:Carbonates; D010087:Oxides; D013458:Sulfur Dioxide; D002245:Carbon Dioxide; D007854:Lead; C005686:sodium carbonate; C047365:lead oxide; D013455:Sulfur
keywords: Lead; Recovery; Spent lead acid battery paste; Vacuum thermal reduction