EM - Escola de Minas

URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/6

Notícias

A Escola de Minas de Ouro Preto foi fundada pelo cientista Claude Henri Gorceix e inaugurada em 12 de outubro de 1876.

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Filtros

2009 - 20102

Configurações

Autor: search.filters.author.Santos, Fabiano Mariel Fernandes dos

Resultados da Pesquisa

Agora exibindo 1 - 2 de 2
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    Effect of iron in zinc silicate concentrate on leaching with sulphuric acid.
    (2009) Souza, Adelson Dias de; Pina, Pablo dos Santos; Santos, Fabiano Mariel Fernandes dos; Silva, Carlos Antônio da; Leão, Versiane Albis
    It is shown that the iron content in zinc silicate concentrates with either high (8–11%) or low (3%) iron does not significantly affect the kinetics or overall recovery of zinc extraction in sulphuric acid. Most of the iron was present as hematite and franklinite with little iron contained in willemite. A small reduction in zinc recovery from 98.5% to 97.5% was observed for silicate ores containing 12% iron. The activation energy determined from high-iron concentrate leaching, 78±12 kJ/mol, is statistically similar to that from low-iron concentrate, 67±10 kJ/mol, suggesting the same rate-controlling step. The leaching of high high-iron concentrates enables a higher mass recovery during flotation. A flowsheet is proposed comprising a magnetic separation step to produce a magnetic and a non-magnetic product so that iron dissolution from the magnetic concentrate acts as a source of soluble iron for impurities removal.
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    The kinetics of zinc silicate leaching in sodium hydroxide.
    (2010) Santos, Fabiano Mariel Fernandes dos; Pina, Pablo dos Santos; Porcaro, Rodrigo Rangel; Oliveira, Víctor de Andrade Alvarenga; Silva, Carlos Antônio da; Leão, Versiane Albis
    The alkaline leaching kinetics of a zinc silicate ore assaying 34.1% Zn, 11.1% Fe and 22.9% SiO2 is studied in sodium hydroxide solutions. Speciation diagrams indicate zinc dissolution as [Zn(OH)4]2− and SEM analysis showed a progressive reduction in particle size during leaching which supports the shrinking particle model. The process is chemically controlled with an activation energy of 67.8±9.0 kJ/mol and reaction order with respect to NaOH determined as 1.44±0.46.