Avaliação da remoção mono e multicomponente de Cu, Zn e Ni em argila bentonita nacional / Cu, Zn and Ni single and multicomponente study using Bentonite

AUTOR(ES)
DATA DE PUBLICAÇÃO

2007

RESUMO

Continuous technological development leads inevitably to residue generation. These grow in volume and toxicity as the increase of industrial processes complexity grow. Due to their high toxicity and non biodegradability, heavy metals specifically can, in extremely low concentrations, be harmful to human health and the environment under any type of exposure. This research analyzed the influence of Nickel, Zinc and Copper mixtures in a fixed bed bentonite adsorption process and gathered new data for a greater understanding of this technology. Bentonite supplied from São Jorge of Ipubi s mine was used for the adsorption tests. It was prepared and classified in order to fit the fluid dynamic process. Heat treatment was found necessary to assure physical stability on the fixed bed set. Single component ionic metal adsorption study was carried out with 3.38 mm grain size bentonite to evaluate the feed flow and initial concentration influence on the metal removal. A mixture design was then set with feeding flow fixed at 5 mL/min and clay mean diameter at 0.545 mm. In mixture design experiments 90 ppm initial concentration single component solutions were done followed by 90 ppm total initial concentration of binary and tertiary multicomponent experiments. Total metal removal (Q) was calculated based on the metal volume required for clay saturation on the single component metal experiments. Binary and tertiary interactions were evaluated as well as the effects of metal mixtures on Q, Qu (breakthrough removal) and ZTM (mass transfer zone). In all cases bentonite pointed out greater affinity in mixture conditions following the order: Cu>Zn>Ni. Models were proposed and evaluated to fit the effects of the mixture conditions over the response variables evaluated (Q, Qu and ZTM) and a high predictability was found for Q and Qu- ZTM, despite presenting a lower predictability compared to the other two had no lack of fit whatsoever

ASSUNTO(S)

engenharia ambiental metais pesados bentonite cooper heavy metals mistura (quimica) misture design environmental control nickel adsorção bentonita zinc mixing fixed bed adsorption

ACESSO AO ARTIGO

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