63 Session 1. Biomass for Biorefneries POTENTIAL OF EUCALYPTUS BARK FOR BIOFUELS PRODUCTION Romaní, Aloia 1 ; Yáñez, Remedios 2,3 ; Larramendi Antonio 4 ; Cancela, Ángeles 4 ; Sánchez, Ángel 4 ; Teixeira, José A. 1 ; Domingues, Lucília 1 1 CEB-Centre of Biological Engineering, University of Minho (Campus Gualtar, Braga, Portugal) 2 Chemical Engineering Department, Faculty of Science, University of Vigo (Campus Ourense, Ourense, Spain) 3 CITI-Tecnopole, (San Ciprián de Viñas, Ourense, Spain) 4 Chemical Engineering Department, EEI, University of Vigo (Campus Vigo, Vigo, Spain) * Corresponding author. E-mail: aloia@ceb.uminho.pt Keywords: Biorefinery, Delignification, Eucalyptus bark, Organosolv pretreatment Abstract Eucalyptus bark has been identified as novel source of biomass for sustainable production of biofuels. In this work, Eucalyptus nitens bark (EBN) was characterized and evaluated for ethanol production. For that, an experimental design was carried out to optimize organosolv delignification process in which the variables temperature (170-200 ºC), time (30-90 min) and percentage of ethanol (50-80 %) were studied. Organosolv process was suitable for the fractionation of E. nitens bark in which up to 93 % of glucan recovery and 50 % of delignification were achieved. After organosolv pretreatment, delignified E. nitens samples bark were submitted to simultaneous saccharification fermentation (SSF) using an industrial Saccharomyces cerevisiae strain. Results obtained from SSF assays showed that the variables temperature and time of delignification process had a significant influence on ethanol production. The organosolv pretreatment improved the ethanol yield from 36 to 96 %. The process proposed in this work shows a suitable use of bark residue for biofuel production. INTRODUCTION The increasing worldwide population coupled with the industrialization and the development of emerging economies results in increasing energy demand. Environmental concerns related to this industrialization promotes the search of alternative, sustainable