Estudos de adsorção de poliaromáticos em materiais nanoporosos

Abstract

The removal of aromatics from mineral naphthenic oil by adsorption was studied. Commercial adsorbents were evaluated using batch experiments. The equilibrium data were fitted using the Langmuir equation. Column experiments were performed for three activated carbons samples that presented the best batch adsorption properties. A simulation model was used to predict the breakthrough curves for adsorption and desorption runs. After three cycles of adsorption/desorption, using n-hexane as eluent, only a slight decrease in aromatics capacity was observed. Activated carbon seemed to be adequate for aromatics removal in this system. Textural properties and detailed study of adsorption was performed using synthetic mixtures of pyrene. The adsorption capacities of adsorbents were obtained by batch experiments in three different temperatures and the isotherms were well adjusted by Langmuir equation. The dynamic adsorption was evaluated by successive breakthrough curves. The dynamic adsorption isotherms were well obtained from these experiments and were also well adjusted by Langmuir equation. The general model that account both internal and external resistances of mass transfer were used to predict the breakthrough curves and estimate the pore diffusivity.