Leaching behavior of zinc and lead from electric arc furnace dust – Poly(vinyl) chloride residues after oxidative thermal treatment

Al-Harahsheh, Mohammad; Altarawneh, Sanad; Al-Omari, Mohammad; Altarawneh, Mohammednoor; Kingman, Sam; Dodds, Chris

Abstract

Oxidative thermal treatment of electric arc furnace dust (EAFD) mixed with poly(vinyl) chloride (PVC) was carried out to study the impact of oxidizing environment on the extraction of valuable metals. The effect of oxygen partial pressure, temperature and holding time of the thermal treatment, as well as the pH of the leaching solution were considered as operational variables in this study. HCl evolved during PVC decomposition was found to react with the metal oxides present in EAFD producing metal chlorides. It was found that thermal treatment above 350 °C caused significant vaporization of lead and zinc chlorides. After thermal treatment, the residue was leached in water, the cheapest available leaching reagent. Zinc and lead were extracted with recoveries up to ∼100%, while iron recovery was as low as 12.5% being suppressed by oxidation of ferrous iron. Operating under oxidative conditions supresses the post dissolution of iron in water by oxidizing Fe3O4 to Fe2O3 and by oxidizing any formed FeCl2 back to Fe2O3. The solution pH was also found to significantly affect the extraction of both lead and iron, especially at pH values above 4.0 where a sharp drop in metals recovery was observed. The obtained results present base for development of sustainable solution for treatment of PVC and EAFD wastes.

• Journal Article Type: Article
• Acceptance Date: Nov 5, 2021
• Online Publication Date: Nov 12, 2021
• Publication Date: Dec 15, 2021
• Deposit Date: May 12, 2023
• Journal: Journal of Cleaner Production
• Print ISSN: 0959-6526
• Peer Reviewed: Peer Reviewed
• Volume: 328
• Article Number: 129622
• DOI: https://doi.org/10.1016/j.jclepro.2021.129622
• Keywords: Industrial and Manufacturing Engineering; Strategy and Management; General Environmental Science; Renewable Energy, Sustainability and the Environment; Building and Construction
• Public URL: https://nottingham-repository.worktribe.com/output/20566134
• Publisher URL: https://www.sciencedirect.com/science/article/abs/pii/S0959652621038002?via%3Dihub