Production of zinc oxide from hazardous waste - Sal Ammoniac Skimming
This article deals with hydrometallurgical treatment with the subsequent precipitation of zinc from hazardous waste Sal- Ammoniac Skimming produced in wet hot-dip galvanizing process. Chemical analysis showed that skimming contained 46.64% Zn. X-ray diffraction analysis identified the Zn(OH)Cl phase...
Main Authors: | , , , , , |
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Format: | Article |
Language: | English |
Published: |
Technical Faculty, Bor
2018-01-01
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Series: | Journal of Mining and Metallurgy. Section B: Metallurgy |
Subjects: | |
Online Access: | http://www.doiserbia.nb.rs/img/doi/1450-5339/2018/1450-53391800027P.pdf |
Summary: | This article deals with hydrometallurgical treatment with the subsequent precipitation of zinc from hazardous waste Sal- Ammoniac Skimming produced in wet hot-dip galvanizing process. Chemical analysis showed that skimming contained 46.64% Zn. X-ray diffraction analysis identified the Zn(OH)Cl phase (96.36%) and NH4Cl (3.64%) in Sal-Ammoniac Skimming. The skimming was first subjected to leaching in order to extract zinc into the solution containing HCl, followed by precipitation of the zinc. The experiments were performed in a medium of HCl at concentrations of 0.25, 0.5, 1 and 2M. Complete dissolution of zinc was achieved in 0.5M HCl solution, at 40°C, L:S=20, max. 30 min. The apparent activation energy of leaching reaction by hydrochloric acid solution was Ea=5.543 kJ mol-1. Zn precipitation was carried out using Na2CO3 and NaOH. Zinc oxide with a purity of about 99% was obtained directly from the solution of 6M NaOH at a temperature of 60°C – 80°Cat pH 8.8. |
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ISSN: | 1450-5339 2217-7175 |