Indonesian Student Association in Thailand (PERMITHA)
Abstract
Gadung (Dioscorea hispida) is a tuber that is non-food because it contains cyanide (HCN). Starch content in gadung tuber is 30.9% so that it worth to manufacture bioethanol. Bioethanol is a product of hydrolysis of starch to glucose, followed by fermentation of glucose using yeast Saccharomyces cereviceae to bioethanol. In this research, bioethanol was made from gadung starch. The hydrolysis process produces 7.85-10.48% glucose and fermentation process produces 5-8.5% crude ethanol. Bioethanol produced from distillation unit was 80%, corresponding to the technical specifications desired. The Design of 1-stage distillation unit has completed, includes the shape and dimensions of the tools, i.e. the main condenser, cylinder-shaped, dimensions of diameter is 32cm and height is 45cm, feeder tank / boiler cylinder-shaped, small scale volume of 5L. At distillation column, the diameter is 9cm and length is 121cm. Column is filled with ceramic or glass type packing inside. Column is equipped with thermometer to measure the temperature of ethanol-water vapor. Two stages distillation unit into one stage can produce 82% ethanol which is fit as fuel for household stoves.
