Daftar Isi:
  • The use of ethanol as a fuel mixture has become the primary choice in many countries, as a result of the energy crisis that is happening right now. Selection of Green Algae as a feedstock is based on the availability of raw materials in Indonesia which is relatively abundant. The purpose of this research to prove that Green Algae can be used as raw material for making ethanol. Green Algae (Cladophora sp) has carbohydrate content 52,54-60,98% (Khuantrairong et al.,2011). The process of cracking cellulose contained in green algae using sulfuric acid hydrolysis process with concentration 0.1 M. Hydrolysis process is helped by heating 80 ° C for 1 hour. The fermentation of Green algae is done for 7 days, assisted by Sacharomyces cerevisiae with variation of fermentatation 5 gr, 12,5 gr 7,5 gr, 10 gr, 12,5 gr, 15 gr, and 17,5 gr. Bioethanol products were analyzed using gas chromatography to find ethanol concentration, refractive index using refractometer, density using pycnometer, the degree of acidity (pH) and the flame test to the bioethanol product. This result of this research showed that this optimum point in the fermentation of yeast mass is the mass of the addition of 12,5 gr of yeast which found the highest purity of bioethanol is 59,21%, with a specific gravity approaching bioethanol standar is 0,853 gr/ml, and then to index bias approaching the refractive index bof ethanol standar is 1,34768. Key words: Green Algae, Hydrolysis, Fermentation, Bioethanol