Method for preparing isopropyl alcohol

A method for preparing isopropyl alcohol, the method comprising:

• supplying a feed including isopropyl alcohol, water, and by-products to a first region of a separation wall-type distillation column which is divided into the first region, a second region, and an upper region by a separation wall and performing azeotropic distillation in the presence of an azeotropic agent;
• discharging a lower discharge stream of the first region including isopropyl alcohol and the by-products from a lower portion of the first region;
• discharging a lower discharge stream of the second region including water from a lower portion of the second region;
• supplying an upper discharge stream including water and the azeotropic agent, which is discharged from an upper portion of the upper region, to a layer separator, separating the stream into an aqueous phase stream including water and an oil phase stream including the azeotropic agent, refluxing the oil phase stream to the upper region, and refluxing the aqueous phase stream to the second region;
• and
• obtaining isopropyl alcohol from the lower discharge stream of the first region.