Abstract:
Ethanol consumption of the world for a variety of uses has increased very significantly in recent years. Therefore it is necessary to alternate sources of raw materials to manufacture bioethanol and bioethanol production can be increased. Nipa sap is one of potential materials to be processed into bioethanol. Availability of nypa palm land in Indonesia and a fairly high sugar content (15-20%) makes nipa sap has the potential to be processed into bioethanol. Through a fermentation process using yeast Saccharomyces cereviceae, glucose is converted into bioethanol and carbon dioxide. Starter preparation is done by the yeast Saccharomyces cereviceae inoculum in the 10% of fermentation medium so that yeast is able to adapt and ready for fermentation. Fermentation takes place in batches with a volume of 50 liters of fermentation medium, variety of nutrient enrichment KH2PO4 (0.6, 0.9 1.2 g / l), MgSO4.7H2O (0.3, 0.4, 0.5 g / l) , and (NH4) 2SO4 (0.5, 0.6, 0.7 g / l) and variations of fermentation time 24, 30, 36, 42, 48, 54, 60, 66 and 72 hours. Stirring speed of 200 rpm and temperature of fermentation at room temperature (25 - 300C). Ethanol concentration was analyzed by using Alkoholmeter. The process of optimum fermentation conditions shown in run 3 with variations addition to a concentration of 0.5, 0.7, 1.2 g / l and fermentation time 60 hours with initial sugar concentration of 205.278 mg / ml. Ethanol concentrations obtained in these conditions was 13% (v / v) or 102.609 mg / ml with the acquisition of 98.010% yield.
