Biossorção de íons metálicos utilizando caroço de açaí (Euterpe Oleracea Mart.) como adsorvente alternativo
| Ano de defesa: | 2014 |
|---|---|
| Autor(a) principal: |
Rech, Angela Laufer
 |
| Orientador(a): |
Gonçalves Júnior, Affonso Celso
|
| Banca de defesa: |
Silva, Tiago Roque Benetoli da
,
Stangarlin, José Renato
,
Oliveira, Paulo Sérgio Rabello de
,
Dragunski, Douglas Cardoso
|
| Tipo de documento: | Tese |
| Tipo de acesso: | Acesso aberto |
| Idioma: | por |
| Instituição de defesa: |
Universidade Estadual do Oeste do Paraná
Marechal Cândido Rondon |
| Programa de Pós-Graduação: |
Programa de Pós-Graduação em Agronomia
|
| Departamento: |
Centro de Ciências Agrárias
|
| País: |
BR
|
| Palavras-chave em Português: | |
| Palavras-chave em Inglês: | |
| Área do conhecimento CNPq: | |
| Link de acesso: | http://tede.unioeste.br:8080/tede/handle/tede/1458 |
Resumo: | The biosorption configures as alternative for the remediation of contaminated waters. Thus, this study aimed to investigate the potential of the use of endocarp of açaí berry (Euterpe oleracea M.) as alternative adsorbent for the removal of Cd2+, Pb2+, Cr3+, Cu2+ and Zn2+ of aqueous contaminated solutions. After the biosorbent characterization by scanning electron microscopy and infrared spectroscopy were performed adsorption tests aiming to determine the ideal conditions of pH, adsorbent mass and contact time for the adsorption process. The kinetics of adsorption was evaluated by the models of pseudo first order, pseudo second order, Elovich and intraparticle diffusion. Also were performed comparative studies with active coal. Besides, were evaluated the desorption capacity of adsorbents and the influence of temperature in the adsorption process. By the obtained results were built adsorption isotherms, which were linearized by mathematical models of Langmuir, Freundlich and Dubinin-Radushkevich. The structural characterization of the biosorbent allowed identifying functional groups such as lignin and celluloses, and the morphological characterization shown a lamelar structure. By the presence of all the above characteristics the biosorbent present favorable conditions for metallic ions adsorption. The studies relating adsorbent mass of endocarp of açaí berry and pH of contaminated solution indicate an ideal pH of 6.0 and 5.0 for Cd2+, Pb2+ and 4.0 for Cr3+, Cu2+ and Zn2+, as well the use of 8, 20 and 12 g L-1 (adsorbent mass by solution volume). The time for dynamic equilibrium for biosorption process was 60 min. The kinetic models suggest for all metallic ions evaluated, the limiting pass for biosorption may be chemisorption. According to adsorption isotherms, the model which represented the best fitting for biosorption of Cd2+, Cr3+, Cu2+ and Zn2+ was Langmuir, indicating a monolayer adsorption. However, for Pb2+ the model with best fitting was Freundlich, which assumes a multilayer adsorption. The values for desorption were low, indicating a strong interaction of the metals with adsorbent surface. The thermodynamic parameters indicate that for Cd2+, Pb2+, Cu2+ and Zn2+ the biosorption process is spontaneous and endothermic. For Cr3+, the process is not spontaneous and from exothermic nature. In general, by the obtained results, it can be concluded that the use of endocarp from açaí berry as biosorbent is an alternative for remediation of contaminated waters, once this material is natural and with low cost and high availability |