Modeling in a fixed bed column for the bio adsorption of Cd⁺² and Pb⁺² with cocoa shell

In this work the results of the bio sorption of Pb⁺² and Cd⁺² with cocoa shell in fixed bed columns are presented. A hydrodynamic study was performed varying diameter and height of the column, as well as diameter and mass of bio sorbent, to determine the best hydrodynamic conditions, which resulted in a flow through the column of 2.12 ml/min. Experimental data were adjusted to several models depending on the effluent volume, which describe the rupture curve for single component and two component systems. The removal percentages of Pb⁺² and Cd⁺² in single component systems are 91 and 90 %, respectively. In bi component systems (Pb⁺² -Cd⁺²) the removal percentages of lead and cadmium were 88 and 90 %, respectively. The dose-response model in bi and mono component system best reproduced the experimental rupture curves throughout the measured range. To identify the functional groups, the Fourier Transform Infrared Spectroscopy (Ftir) technique was used in a Perkin Elmer spectrophotometer, model 20 SXB. The concentrations of lead and cadmium were determined by atomic absorption spectrometry, using a Perkin Elmer A Analyst 400 spectrophotometer. (author)