LIQUID – LIQUID SEPARATION OF BENZENE FROM ALKANES

Abstract

Light cycle oil (LCO), which is a product of the catalytic cracking of the vacuum gas oil in the FCCU, contains a good percentage of aromatics, monocyclic and polycyclic. These compounds need to be separated from the streams, as these are not very suitable in the further conversion units and can add value to the specialized streams. In this study, liquid-liquid extraction (LLE) diagram for ternary systems Isooctane-Benzene-NMP and n-heptane-Benzene-NMP have been prepared. From the experimental LLE data, the selectivity and the solute distribution ratio were calculated. The degree of consistency of the tie-lines was tested using the Othmer-Tobias equation, Hand’s Plot and Bachman’s correlation. Also, the experimental LLE data were correlated using nonrandom two-liquid (NRTL) and universal quasichemical (UNIQUAC) thermodynamic models. Moreover, a systematic study about the influence of the size of the aliphatic hydrocarbonon the aromatic extraction was carried out.