PRODUCTION OF BIO-ETHANOL FROM JATROPHA OILSEED CAKES VIA DILUTE ACID HYDROLYSIS AND FERMENTATION BY SACCHAROMYCES CEREVISIAE

Abstract

This work deals with the bioconversion of cellulose from press cakes of Jatropha oilseeds, which is a byproduct from a biodiesel plant, into ethanol by using the methods of acid pretreatment, hydrolysis and fermentation by Saccharomyces cerevisiae. The process includes the pretreatment method of the finely ground cellulosic solid oilseed cake with dilute sulphuric acid and heating the mixture at a high temperature to break the crystalline structure of the lignocellulose to facilitate the hydrolysis of cellulosic component by dilute acids. The hydrolysis of the cellulose content into sugars is done by dilute acid hydrolysis that involves incubation period at a high temperature for 72 hours. Finally, the fermentation of the hydrolyzed waste is done using Saccharomyces cerevisiae under proper incubation conditions to produce ethanol. About 80 % ethanol was recovered as a result of the process.