Distillation device

A distillation device, comprising a first distillation unit that comprises a first condenser, a first reboiler and a first distillation column;

• a second distillation unit that comprises a second condenser, a second reboiler, and a second distillation column and is connected to the first distillation column;
• and a heat exchanger,
• wherein a raw material comprising compounds represented by Formulas 1 and 2 below is introduced into a first supply port of the first distillation column,
• the raw material introduced into the first supply port of the first distillation column is separately discharged into each of a first top stream discharged from an upper section of the first distillation column and first, second and third bottom streams separately discharged from a lower section of the first distillation column,
• the first top stream is introduced into the first condenser, and a portion or all of the first top stream passing through the first condenser is refluxed into the upper section of the first distillation column,
• the first bottom stream is introduced into the first reboiler, and the first bottom stream passing through the first reboiler is refluxed into the lower section of the first distillation column,
• the second bottom stream is introduced into the second supply port of the second distillation column,
• the steam introduced into the second supply port of the second distillation column is separately discharged to each of a second top stream discharged from an upper section of the second distillation column, and fourth and fifth bottom streams discharged from a lower section of the second distillation column,
• the fourth bottom stream is introduced into the second reboiler, and the fourth bottom stream passing through the second reboiler is refluxed into the lower section of the second distillation column,
• the second top stream and the third bottom stream are introduced into the heat exchanger, the third bottom stream passing through the heat exchanger is refluxed into the lower section of the first distillation column, the second top stream passing through the heat exchanger is introduced into the second condenser, and the second top stream passing through the second condenser is refluxed into the upper section of the second distillation column, and
• Equations 1 and 2 are satisfied:
• wherein R1 is a C4 to C12 alkyl group, and R2 to R4 are each independently hydrogen or a C4 to C12 alkyl group,
• R5 is a C1 to C4 alkyl group, and n is 1 to 4;
• Tt-2−Tb-3≧8° C., [Equation 1]
• P2/P1≧3.0, [Equation 2]
• wherein Tt-2 indicates a temperature of the second top stream F2-2, and Tb-3 indicates a temperature of the third bottom stream F1-5, and
• P1 indicates a pressure (kg/cm2g) of the upper section of the first distillation column, and P2 indicates a pressure (kg/cm2g) of the upper section of the second distillation column.