Liquid-liquid equilibrium (LLE) data for the systems heptane + o-xylene + tetraethylene glycol (TTEG) have been experimentally studied over the temperature range (293 to 313) K. The experimental data of this work, in addition to 22 isothermal sets of LLE data (from the literature) for the extraction of aromatics from hydrocarbon mixtures using TTEG, are analyzed using two models. The models used are the empirical Othmer-Tobias correlation and the thermodynamic UNIQUAC model as programmed in the Aspen Plus simulator. For each data set, the analysis performed by the Othmer-Tobias correlation involves the determination of the model's parameters by regressing each set of data. The predictive capability of the UNIQUAC model has been investigated in terms of deviations for the mole fraction of the target aromatic species in the extract phase. Direct fitting of the data of this work using the Othmer-Tobias model gives an average rms (root-mean-square) of 0.002 in TTEG mass fraction in the extract phase, whereas prediction using UNIQUAC gives an average rms of 0.15.
ASJC Scopus subject areas
- Chemical Engineering(all)