Thursday, April 22, 2010 - 4:30 PM
Investigation of the fermentability of hydrolysate mixed with molasses and their impacts on bioethanol production
Sarita C. Rabelo1, Rafael Ramos de Andrade1, Francisco Maugeri Filho2, Rubens Maciel Filho1, and Aline Carvalho da Costa1. (1) Department of Chemical Processes – School of Chemical Engineering, University of Campinas, Cidade Universitária, Campinas, Brazil, (2) Department of Food Engineering– School of Food Engineering, University of Campinas, Cidade Universitária, Campinas, Brazil
One of the main targets in bioethanol production to achieve sustainability is the increase in the productivity per area of sugarcane cultivated. This is possible through the use of the cellulosic portion of sugarcane as a substrate source in the fermentation.
Among the drawbacks in the second generation biofuel technology is the presence of inhibitory products in the hydrolysates (acetic acid, furfural and hydroxymethylfurfural (HFM)), which inhibit the kinetics and productivity of alcoholic fermentation.
In this work, the fermentability of a mixture of sugarcane molasses and the hydrolysates obtained after enzymatic hydrolysis of bagasse pretreated using two distinct processes (pretreatment with lime and hydrogen peroxide) at different proportions (from 5% to 45% vol. of hydrolysate added in the fermentation broth) was investigated in a continuous process. The microorganism used was a lineage of Saccharomyces cerevisiae. The hydrolysate was cold sterilized by a membrane of 0.45 µm in order to maintain the original concentrations of furfural and HMF in the media to evaluate their inhibitor impacts on the yeasts.
The kinetics of bioethanol formation, yield and productivity was evaluated for continuous mode of production at five different temperatures, from 30 to 38°C.
Among the drawbacks in the second generation biofuel technology is the presence of inhibitory products in the hydrolysates (acetic acid, furfural and hydroxymethylfurfural (HFM)), which inhibit the kinetics and productivity of alcoholic fermentation.
In this work, the fermentability of a mixture of sugarcane molasses and the hydrolysates obtained after enzymatic hydrolysis of bagasse pretreated using two distinct processes (pretreatment with lime and hydrogen peroxide) at different proportions (from 5% to 45% vol. of hydrolysate added in the fermentation broth) was investigated in a continuous process. The microorganism used was a lineage of Saccharomyces cerevisiae. The hydrolysate was cold sterilized by a membrane of 0.45 µm in order to maintain the original concentrations of furfural and HMF in the media to evaluate their inhibitor impacts on the yeasts.
The kinetics of bioethanol formation, yield and productivity was evaluated for continuous mode of production at five different temperatures, from 30 to 38°C.