Modeling the biosorption of basic dyes from binary mixtures

The biosorption of basic dyes, methylene blue and rhodamine B, from binary aqueous solutions onto cypress cone chips, was analyzed through mathematical modeling. This study aimed at introducing a novel model to predict the dynamic binary sorption of the dyes. It consisted of a modified Langmuir multicomponent isotherm coupled with a linear driving force model. Experimental data from recent studies using the untreated and alkaline-treated biosorbent was used to determine the model parameters, and the breakthrough predictions are in good agreement with the experimental results. Useful information on the effects of bed length and feed concentration on the breakthrough time and mass transfer length was obtained. This can guide the design and optimization of the biosorbent column.