Study On Separation Of Azeotrope Ethyl Acetate-tertiary Butanol

Ethyl acetate (EA) and tertiarybutanol (TBA) are widely used in chemical andpharmaceutical industrial processes as chemical raw materials and excellent organicsolvents. However, their mixture is azeotropic that cannot be separated by ordinarydistillation methods. At present, the separation methods and processes of the EA-TBAbinary azeotrope have not been reported in the literature.This paper studied on the separation process of binary azeotropic mixtureEA-TBA by extractive distillation.At first, several solvents were picked out according to some empirical andqualitative rules. Furthermore, DMSO was selected as the appropriate solvent byUNIFAC group contribution method. Then, the experiment of ternary vapor-liquidequilibrium was conducted. The experiment data were correlated by means ofUNIFAC equation. It was concluded that, the azeotrope disappeared when the massfraction of DMSO was0.5. What’s more, the calculation results of UNIFAC modelmatched well with the experiment data.Then, Aspen Plus software was used to simulate and optimize the continuousextractive distillation process of separating EA-TBA. For the double-columncontinuous extractive distillation, the purities of EA and TBA were99.90%wt and99.88%wt, which yields were99.94%and99.98%, respectively.At last, the small scale batch extractive distillation was carried out to separate EAand TBA, appropriate reflux ratio and solvent ratio were selected by comparativeexperiments. The purities of EA and TBA were99.97%wt and99.20%wt, whichyields per pass were85.51%and23.81%, respectively.