Energy conservation during plural stage distillation

摘要

A multistage distillation method for the purification of a methyl tertiary butyl ether reaction product in a recovery zone comprising distillation columns equipped with reflux condensers and reboilers and wherein the methyl tertiary butyl ether reaction product is separated in a primary methyl tertiary butyl ether distillation column into a higher boiling methyl tertiary butyl ether distillation fraction and a lower boiling aqueous tertiary butyl alcohol fraction, wherein the lower boiling aqueous tertiary butyl alcohol fraction is separated in a tertiary butyl alcohol recovery column into a vaporized overhead tertiary butyl alcohol fraction and a lower boiling water fraction,   wherein cooling water is charged to the reflux condenser for the tertiary butyl alcohol distillation column to liquify the vaporized, overhead tertiary butyl alcohol fraction and to convert the cooling water to low pressure steam, and   wherein low pressure steam generated in said reflux condenser for said tertiary butyl alcohol distillation column is charged to the reboiler for the primary methyl tertiary butyl ether distillation zone to supply the heat necessary for the distillation to be effected therein.