Tuesday, May 6, 2008 - 9:00 AM
8-03
Decreasing of recalcitrance of sugarcane bagasse cellulose by steam pretreatment
Luis R M Oliveira, George J M Rocha, and Adilson R. Gonçalves. Biotechnology Department, Engineering School of Lorena- EEL-USP, Rodovia Itajubá - Lorena - Km 74,5 - Bairro Campinho, Lorena-SP, Brazil
Several technologies to convert biomass into ethanol have been developed in the last years due to recent alert on fossil fuel´s finitude and environmental damages. To obtain ethanol from biomass usually three steps are needed: (i) pretreatment, (ii) hydrolysis of cellulose and (iii) fermentation of sugars. In this work a new technology of pretreatment to sugarcane bagasse was evaluated: a type of steam explosion with slow decompression. In Brazil , this type of pretreatment is used to produce animal feed. The trials were carried out in a 5m3 reactor, kindly furnished by Usina Vale do Rosário (Sugar and Alcohol Company). After pretreatment, the bagasse was alkaline-extracted using 1% (w/v) NaOH for 1 h. Enzymatic hydrolysis was took place using two commercial enzymes (Celluclast 1.5 L e Novozym 188, both from Novozymes Company). Conversion yield of pretreated followed by alkaline extracted bagasse shows that the two previous steps were important for the enzymatic hydrolysis of cellulose. The hydrolyzate has 15 g .L-1glucose concentration, corresponding to 85% of conversion yield. [Acknowledgments due to FAPESP and CNPq – Brazilian agencies]