SEPARATION OF TERTIARY BUTYL ALCOHOL - WATER SYSTEM BY USING LITHIUM BROMIDE

Extractive distillation is used for the separation of azeotropic mixture of tertiary butyl alcohol and water. Tertiary butyl alcohol is used as a solvent, ethanol denaturant, paint remover ingredient and also used as gasoline octane booster. Tertiary butyl alcohol makes an azeotrope at 79.9 oC, containing 11.8% water. In this work addition of salt helped to break the azeotrope by changing the relative volatility of the mixture facilitating separation effectively than the conventional method .Extractive distillation at 80oC, was carried out by varying the concentration of salt LiBr (10, 15, 20, 25, 30 & 35 g.) in TBOH-Water azeotropic mixture and it was found that 88.98 (wt. %) separation of TBOH was achieved for (35 g.) salt concentration. I. Introduction Extractive distillation is basically used to separate azeotropes and other mixtures that have key components with a relative volatility below about 1 over an appreciable range of concentration. The conventional method for separation of azeotropic composition is by using extractive distillation addition of solvent to break the azeotrope with an extra separation step is needed to recover the solvent which adds extra cost to the separation. A separation solvent is used in the method of extractive distillation. It is being chosen depending upon various factors that is it should be non-volatile, has a high boiling point and is miscible with the mixture, but doesn't