Alternative Schemes for the Purification of Bioethanol: A Comparative Study

Abstract

The increase in the worldwide production of Bioethanol is simultaneous with the development of new technologies to obtain it from waste containing cellulose and hemicelluloses. This situation can give value to the wastes from various industries converting them into raw material for the production of Bioethanol by a fermentation process. Bioethanol yields obtained in the fermentation are usually low, so it must be purified further in separation sequences based on distillation, which usually consume large amounts of energy. In this paper, taking as basis the well known conventional process for purification of Bioethanol, new hybrid arrangements for the purification of ethanol are proposed, based on the combination of liquid-liquid extraction (using n-dodecane as solvent) and extractive distillation (using different entrainers). The results show that these alternative configurations, with the presence of thermal coupling, can generate an alternative purification process to obtain high purity ethanol with low energy consumption, low operating costs and reduction in emissions of greenhouse gases in the process.