title: The leaching kinetics of cadmium from hazardous Cu-Cd zinc plant residues.
abstract: A large amount of Cu-Cd zinc plant residues (CZPR) are produced from the hydrometallurgical zinc plant operations. Since these residues contain substantial amount of heavy metals including Cd, Zn and Cu, therefore, they are considered as hazardous wastes. In order to realize decontamination treatment and efficient extraction of the valuable metals from the CZPR, a comprehensive recovery process using sulfuric acid as the leaching reagent and air as the oxidizing reagent has been proposed. The effect of temperature, sulfuric acid concentration, particle size, solid/liquid ratio and stirring speed on the cadmium extraction efficiency was investigated. The leaching kinetics of cadmium was also studied. It was concluded that the cadmium leaching process was controlled by the solid film diffusion process. Moreover, the order of the reaction rate constant versus H2SO4concentration, particle size, solid/liquid ratio and stirring speed was calculated. The XRD and SEM-EDS analysis results showed that the main phases of the secondary sulfuric acid leaching residues were lead sulfate and calcium sulfate.
authors.affiliation: School of Metallurgy, Northeastern University, Shenyang 110819, China; National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; Department of Materials Engineering, University of British Columbia, Vancouver V6T1Z4, Canada.
authors.forename: Meng
authors.initials: M
authors.lastname: Li
authors.affiliation: National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Shili
authors.initials: S
authors.lastname: Zheng
authors.affiliation: National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Biao
authors.initials: B
authors.lastname: Liu
authors.affiliation: National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: duhao121@hotmail.com.
authors.forename: Hao
authors.initials: H
authors.lastname: Du
authors.affiliation: Department of Materials Engineering, University of British Columbia, Vancouver V6T1Z4, Canada. Electronic address: david.dreisinger@ubc.ca.
authors.forename: David Bruce
authors.initials: DB
authors.lastname: Dreisinger
authors.affiliation: Department of Materials Engineering, University of British Columbia, Vancouver V6T1Z4, Canada.
authors.forename: Leili
authors.initials: L
authors.lastname: Tafaghodi
authors.affiliation: National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D002104:Cadmium; D006256:Hazardous Waste; D007700:Kinetics; D019216:Metals, Heavy; D015032:Zinc
chemical_list: D006256:Hazardous Waste; D019216:Metals, Heavy; D002104:Cadmium; D015032:Zinc
keywords: Cu-Cd zinc plant residues (CZPR); Diffusion control; Hazardous wastes; Kinetics; Sulfuric acid leaching