Abstract:

Extractive distillation of pharmaceutical waste water containing tetrahydrofuran，methanol was simulated with the ChemCAD software. Glycol was chosen as extractant，and a process with three towers was designed for seperating the mixture. Extractive distillation of tetrahydrofuran separation from the mixture of tetrahydrofuran，methanol and water was modeled with a tower with 24 theoretical plates，the modulate result indicated that tetrahydrofuran recovery could be up to 99.5% with the conditions as follow. The mixture was fed at the 17th plate at its boiling point，the extractant was fed at the second plate at its boiling point，solvent ratio was 1.65 and reflux ratio was 1.5. The glycol recovery tower needed five plates，and the methanol recovery tower needed eighteen plates. The reliability of the extractive distillation modeling result was verified by experiment.