Lead and zinc selective precipitation from leach electric arc furnace dust solutions

Electric-arc furnace (EAF) dust is considered a hazardous industrial waste. In this work, chemical and mineralogical investigations of EAF dust from Siderúrgica Rio-Grandense (RS, Brazil) were performed. The elements aluminum, calcium, lead, cadmium, chromium, magnesium, manganese, nickel, potassium...

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Detalhes bibliográficos
Autores: Lenz,D.M., Martins,F.B.
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2007
País:Brasil
Recursos:Matéria (Rio de Janeiro. Online)
Repositorio:Matéria (Rio de Janeiro. Online)
Idioma:inglés
OAI Identifier:oai:scielo:S1517-70762007000300011
Acesso em linha:http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1517-70762007000300011
Access Level:acceso abierto
Palavra-chave:Electric arc furnace dust
zinc
lead
leaching
Descrição
Resumo:Electric-arc furnace (EAF) dust is considered a hazardous industrial waste. In this work, chemical and mineralogical investigations of EAF dust from Siderúrgica Rio-Grandense (RS, Brazil) were performed. The elements aluminum, calcium, lead, cadmium, chromium, magnesium, manganese, nickel, potassium, silicon, sodium, tin, iron, zinc, sulphur, oxygen, and carbon were found in EAF dust. The concentration of zinc and iron showed an average value of approximately 20% (weight basis) and these elements are mainly present as ZnO.Fe2O3 (zinc ferrite) and ZnO (zincite) mineralogical phases. Also, EAF dusts were submitted to an integrated hydrometallurgical process composed by a hydrolyzed step, followed by a fusion step and a strong alkaline leaching. A subsequent chemical precipitation was carried out in order to promote selective separation of zinc and lead from the leach solution. Sodium sulphide was successfully employed as precipitant agent. When the weight ratio of sodium sulphide to lead was around 2.0, lead could be selectively extracted from leach solution. After lead precipitation without zinc concomitant loss, a weight ratio of sodium sulphide to zinc of around 3.0 was used to precipitate all zinc. Thus, EAF dust has a great potential to be used as a source of metals extraction due to its rich chemical composition and also for the viability of the proposed selective separation process.