title: Selective leaching process for the recovery of copper and zinc oxide from copper-containing dust.
abstract: The purpose of this study was to develop a resource recovery procedure for recovering copper and zinc from dust produced by copper smelting furnaces during the manufacturing of copper-alloy wires. The concentrations of copper in copper-containing dust do not meet the regulation standards defined by the Taiwan Environmental Protection Administration; therefore, such waste is classified as hazardous. In this study, the percentages of zinc and copper in the dust samples were approximately 38.4% and 2.6%, respectively. To reduce environmental damage and recover metal resources for industrial reuse, acid leaching was used to recover metals from these inorganic wastes. In the first stage, 2 N of sulphuric acid was used to leach the dust, with pH values controlled at 2.0-3.0, and a solid-to-liquid ratio of 1:10. The results indicated that zinc extraction efficiency was higher than 95%. A selective acid leaching process was then used to recover the copper content of the residue after filtration. In the second stage, an additional 1 N of sulphuric acid was added to the suspension in the selective leaching process, and the pH value was controlled at 1.5-2.0. The reagent sodium hydroxide (2 N) was used as leachate at a pH greater than 7. A zinc hydroxide compound formed during the process and was recovered after drying. The yields for zinc and copper were 86.9-93.5% and 97.0-98.9%, respectively.
authors.affiliation: a Department of Mechanical Engineering and Green Energy Materials Center , Far East University , Tainan 744 , Taiwan.
authors.forename: Jun-Yi
authors.initials: JY
authors.lastname: Wu
authors.affiliation: b The Experimental Forest , National Taiwan University , Nan-Tou 55750 , Taiwan.
authors.forename: Fang-Chih
authors.initials: FC
authors.lastname: Chang
authors.affiliation: c Department of Environmental Engineering , National Cheng Kung University , Tainan 701 , Taiwan.
authors.forename: H Paul
authors.initials: HP
authors.lastname: Wang
authors.affiliation: b The Experimental Forest , National Taiwan University , Nan-Tou 55750 , Taiwan.|d School of Forestry and Resource Conservation , National Taiwan University , Taipei 10617 , Taiwan.
authors.forename: Ming-Jer
authors.initials: MJ
authors.lastname: Tsai
authors.affiliation: b The Experimental Forest , National Taiwan University , Nan-Tou 55750 , Taiwan.|d School of Forestry and Resource Conservation , National Taiwan University , Taipei 10617 , Taiwan.
authors.forename: Chun-Han
authors.initials: CH
authors.lastname: Ko
authors.affiliation: a Department of Mechanical Engineering and Green Energy Materials Center , Far East University , Tainan 744 , Taiwan.
authors.forename: Chih-Cheng
authors.initials: CC
authors.lastname: Chen
mesh_terms: D003300:Copper / Q000032:analysis / Q000737:chemistry*; D004391:Dust / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste / Q000032:analysis; D008669:Metallurgy; D017942:Nitric Acid / Q000737:chemistry; D059027:Recycling / Q000379:methods*; D012972:Sodium Hydroxide / Q000737:chemistry; D013464:Sulfuric Acids / Q000737:chemistry; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D004391:Dust; D007220:Industrial Waste; D013464:Sulfuric Acids; D017942:Nitric Acid; D012972:Sodium Hydroxide; D003300:Copper; C033158:sulfuric acid; D015034:Zinc Oxide
keywords: copper; copper-containing dust; recovery; selective acid leaching; zinc oxide