Separation of Acetone and n-hexane by Continuous Extractive Distillation with Cyclohexanol As Solvent

Continuous extractive distillation process for acetone-n-hexane azeotropic system is simulated and optimized using Aspen Plus V7.3. By the pseudo-binary phase diagram, cyclohexanol is selected as a suitable extractant.The process of continuous extractive distillation with two columns is confirmed. The separation effect of the number of theory stages, the mixture feed stage, the solvent feed stage, the reflux ratio and the mole ratio of extractant to mixture(solvent ratio) are investigated using sensitivity analysis tool. The optimal condition for the extractive distillation is as follows: the number of theory stages is 33, the mixture feed stage is 29 th, the solvent feed stage is 3rd, the reflux ratio is 0.3, and the solvent ratio is 3. Under the technological condition: The separation effect of acetone of extractive distillation tower of is up to 99.98%. The purity of n-hexane of the extractant-recovery column is 99.89%. The results are useful for the design and operation of continuous extractive distillation process for acetone-n-hexaneazeotropic system