Monday, April 30, 2007

Identifying relations between pre-treatment parameters, enzymatic hydrolysis, and ethanol fermentation using alkaline wet oxidation of reed

Enikô Varga1, Zsófia Kádár1, Anne Belinda Thomsen2, and Kati Réczey1. (1) Agricultural Chemical Technology Department, Budapest University of Technology and Economics, Szt. Gellért tér 4., Budapest, 1111, Hungary, (2) Biosystems Department, Risoe National Laboratory, P.O. Box 49, Roskilde, 4000, Denmark

In the production of bioethanol from lignocellulosics, the subsequent enzymatic hydrolysis and fermentation processes are known to be affected by the pre-treatment technology applied. Wet oxidation has been successfully used to different herbaceous biomasses such as corn stover or wheat straw, resulted in easily degradable cellulose rich biomass for ethanol production. In this study reed, a rarely investigated substrate, was wet oxidised (WO), in order to make the cellulose more accessible to the enzymes in the enzymatic saccharification. The WO reed was also fermented to ethanol using Saccharomyces cerevisiae. Four different combinations of reaction temperature and time were applied for wet oxidation of reed using Na2CO3 as a catalysts to find the best reaction conditions, resulting in both high glucose and ethanol yield. The best condition (195°C, 12 min, 2g/L Na2CO3) increased the enzymatic conversion from cellulose to glucose of reed more then three times. This was achieved with a substrate concentration of 5% (w/w) dry material at 20 FPU/g DM enzyme loading after 24 h enzymatic hydrolysis. The results of the enzymatic hydrolysis and the non-isothermal saccharification and fermentation (SSF) followed WO will be presented.