Fuel Grade Bioethanol Production from Iles-iles (Amorphophaluscampanulatus) Tuber

Fuel grade bioethanol production as an alternative fuel is desirable to substitute fossil fuel as diminishing energy source from petroleum. Bioethanol production from Iles-iles (Amorphophaluscampanulatus) tuber as alternative fuel has been conducted by hydrolysis followed by fermentation. The purification of bioethanol product was performed by distillation (using traditional and automatic distillation) and either adsorption or pervaporation. In hydrolysis process, 140 g/L of reducing sugar was produced, which then was fermented by using yeast Sacharomycescerevisiae (2.5-20 g/L) resulting 50-80 g/L ethanol with the concentration was 7-9% (v/v). In order to obtain 90 L ethanol with 90% purity, traditional distillation equipment required 21 hours operation, whereas automatic distillation required 12.5 hours. Then, adsorption process produced bioethanol 99% with ethanol raw materials at concentrations of 90% and 95% which resulted the breakthrough time of 60 and 120 minutes, respectively. Purification process with membrane pervaporation for 2 hours using ethanol raw material 95% (v/v) produced ethanol 99% (v/v) with ethanol flux was 20 kg/m2.hour.