Bioethanol is produced by fermentation of simple sugars present in biomass or the sugars obtained by prior chemical or enzymatic treatment of the biomass. The fermentation is per- formed by microorganisms, traditionally by yeasts, although some types of bacteria such as Zymomonas mobilis [12] could also be used. After the fermentation, the ethanol is being separated from the fermentation broth, conventionally by means of distilla- tion and rectification or by using more efficient separation technologies such as pervaporation, membrane filtration or mole- cular sieves [12–14]. A schematic of bioethanol production on biomass is presented in Fig. 2