Using the example of ethanol-water, benzene is the entrainer. Ethanol is removed as the bottoms product from the column. Benzene is too hazardous for various reasons ranging from workplace to product to environmental safety. In the above system, the first column is the ordinary azeotropic distillation that produces an ethanol-water azeotrope as the distillate and nearly pure water as the bottoms. The distillate is fed to the second column for extractive distillation, where propylene glycol is added. Ethanol is produced as the distillate, leaving the top of the column.