Determination of Liquid−Liquid equilibria of ethylene glycol + 1,2-Butanediol + 5-Methyl-2-hexanone/Di-isobutyl ketone ternary systems

Two kinds of ketones , 5-methyl-2-hexanone and di-isobutyl ketone were selected as the extraction agents for separating the azeotrope of ethylene glycol (EG)and 1,2-butanediol (1,2-BDO). By comparing the results of preliminary extraction experiments under 303.15 K and normal pressure, 5-methyl-2-hexanone was the better one. And the Liquid-liquid equilibrium data of EG + 1,2-BDO + 5-methyl-2-hexanone ternary system were successively measured at 293.15 K and 313.15 K. The distribution coefficient ( K 2 $K_2$ ) and selectivity coefficient ( S ) of 1,2-BDO were calculated from the experimental data. The LLE data were correlated by NRTL and UNIQUAC activity models with the authorized Aspen Plus software. The root mean square deviations ( RD ) between the experimental and calculated values were all less than 0.7%, which means they were consistent with each other very well.