Fixed-bed adsorption of aromatic C8 isomers: Breakthrough experiments, modeling and simulation

The adsorption of C8 isomers (p-xylene, m-xylene, o-xylene and ethylbenzene) was studied under the industrial operating conditions of the Parex process. Single- and multi-component breakthrough experiments were carried out on a Barium exchanged faujasite-type zeolite as adsorbent and p-diethylbenzene as desorbent. Equilibrium isotherms of the main components of the Parex process were obtained from single component breakthrough curves with different feed concentrations in i-octane. A mathematical model is presented which, jointly with the equilibrium experimental data, is capable of satisfactorily predicting the breakthrough curves of multi-component mixtures of xylenes, including the breakthrough curves of the real Parex feed mixture.

► Breakthrough curves were used to study the adsorption of C8 isomers. ► The sorption parameters were determined from single component breakthrough curves. ► A model for predicting breakthrough curves of mixtures of xylenes was developed. ► We present the results of experiments with the real feed mixture of Parex process.