Characterization of Pequi (Caryocar brasiliense) Shells and Evaluation of Their Potential for the Adsorption of PbIIIons in Aqueous Systems

• Autor(a) principal: Amorim,Dayane J.
• Data de Publicação: 2016
• Outros Autores: Rezende,Hélen C., Oliveira,Érica L., Almeida,Ione L. S., Coelho,Nívia M. M., Matos,Túlio N., Araújo,Cleide S. T.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Journal of the Brazilian Chemical Society (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532016000300616
• topic: PbII adsorption; isotherm; kinetic of biosorption; pequi shell

In this study pequi (Caryocar brasiliense) shells were evaluated in relation to their potential for the adsorption of PbII ions in aqueous systems. The adsorbent was characterized by point of zero charge (PZC), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) and PbII ions were detected by flame atomic absorption spectrometry (FAAS). The adsorption parameters studied were solution pH, adsorbent mass, contact time and the optimum adsorption conditions were found to be 7.0, 50 mg and 30 min, respectively, using 15 mL of the metal solution. A study on the adsorption kinetics and isotherms was performed applying the optimized conditions. The adsorption process followed a pseudo-second-order model. The experimental adsorption data were fitted to the Langmuir and Freundlich isotherm adsorptions and a very good fit to the Langmuir linear model was observed. The maximum adsorption capacity was found to be 35.52 mg g-1.