Computer aided design of continuous extractive distillation processes for the separation of binary azeotrope: Cyclohexane-ethyl acetate with diethylene glycol

The extractant for separating cyclohexane-ethyl acetate by extractive distillation was chosen according to basic selection rules and experiment. Diethylene glycol was chosen as extractant, and a process with two columns was designed for separating the mixture. Effects of the extractant feed position (n(ex)) and the mixture feed position (n(bi)) on the extractive distillation column, the mole ratio of extractant to feedstock (solvent ratio, S/F), and the reflux ratio (R) were investigated. Aimed at the cyclohexane mole fraction (x(CYH)) of 98% in the products and the cyclohexane recovery (y(CYH)) of 98%, the extractive distillation process was simulated to obtain the optimal conditions for the extractive distillation column as follows, number of theoretical plates 24, the mixture feed at 14th plate, the extractant feed at 2nd plate, the solvent ratio 2.02 and reflux ratio 0.9. The extractive distillation simulation result was verified by the experiment data.