Purification of bioethanol using continuous distillation column

Abstract

Bioethanol is a highly demanding renewable energy source which produced through fermentation process. However the separation process of this pure bioethanol from crude fermented bioethanol is a challenging work due to the azeotropic properties of ethanol and water mixture. In this research, continuous distillation column was used to conduct the purification process of bioethanol that has been produced through fermentation process of molasses using Saccharomyces cerevisiae. This fermentation process produces bioethanol at a concentration of 8.32 v/v %. Ethanol-water binary mixture was prepared through dilution of industrial grade ethanol to the concentration of bioethanol. Then it proceeds with continuous distillation process. The efficiency of continuous distillation process was evaluated using three parameters such as reflux ratio, feed flow rate and feed condition. This lab result was validated using COFE and ChemSep simulation Software. Results from validated analysis shows that reflux ratio and feed condition has shown significant effect on the distillation process of bioethanol. Stages increases from 1.79 to 2.26 as the reflux is decreased from 90 % to 45 % and saturated feed produce lower mole fraction of desired product. As for that we can conclude that lower reflux with cold feed condition is more suitable for higher top product mole fraction.