Publicação
Cadmium(II) and zinc(II) adsorption by the aquatic moss Fontinalis antipyretica: Effect of temperature, pH and water hardness
| Resumo: | The biosorption of cadmium(II) and zinc(II) ions onto dried Fontinalis antipyretica, a widely spread aquatic moss, was studied under different values of temperature, initial pH and water hardness. The equilibrium was well described by Langmuir adsorption isotherms. Maximum biosorption capacity of cadmium was independent on temperature and averaged 28.0mg g 1 moss, whereas for zinc, capacity increased with temperature, from 11.5mg g 1 moss at 5 C to 14.7mg g 1 moss at 30 C. Optimum adsorption pH value was determined as 5.0 for both metal ions. Cadmium uptake was unaffected by the presence of calcium ions, but zinc sorption was improved when water hardness increased from 101.1 to 116.3mg CaCO3 l 1. Inversely, as hardness increases, the competition with calcium ions strongly reduces the affinity of the biosorbent for zinc. |
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| Autores principais: | Martins, Ramiro |
| Outros Autores: | Pardo, Rosana; Boaventura, Rui |
| Assunto: | Aquatic moss Zinc Cadmium Sorption Heavy metals Fontinalis antipyretica |
| Ano: | 2004 |
| País: | Portugal |
| Tipo de documento: | artigo |
| Tipo de acesso: | acesso aberto |
| Instituição associada: | Instituto Politécnico de Bragança |
| Idioma: | inglês |
| Origem: | Biblioteca Digital do IPB |
| Resumo: | The biosorption of cadmium(II) and zinc(II) ions onto dried Fontinalis antipyretica, a widely spread aquatic moss, was studied under different values of temperature, initial pH and water hardness. The equilibrium was well described by Langmuir adsorption isotherms. Maximum biosorption capacity of cadmium was independent on temperature and averaged 28.0mg g 1 moss, whereas for zinc, capacity increased with temperature, from 11.5mg g 1 moss at 5 C to 14.7mg g 1 moss at 30 C. Optimum adsorption pH value was determined as 5.0 for both metal ions. Cadmium uptake was unaffected by the presence of calcium ions, but zinc sorption was improved when water hardness increased from 101.1 to 116.3mg CaCO3 l 1. Inversely, as hardness increases, the competition with calcium ions strongly reduces the affinity of the biosorbent for zinc. |
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