Abstract

In this work the acid catalyzed acetone/water organosolv pretreatment for enzymatic hydrolysis (HE) and simultaneous saccharification and fermentation (SSF) of Pinus radiata was evaluated by controlling the H factor of the process. Woods chips were treated with acetone:water (1:1 v/v), 0.9% H2SO4 at H factors from 1000 to 6000; 185-195°C and from 10 to 40 min of reaction. Yields of pretreated substrates were between 55-40%. Pretreated substrates were enzymatic hydrolyzed using Celluclast 1.5 (20 FPU/g cellulose) and Novozyme 188 (40 IU/g cellulose). Best yield in HE (50°C, 72 h) were obtained with the pretreated substrates produced at an H-factor of 3200, in which the theoretical ethanol yield was 72%. SSF was carried out at 40°C, 72 h, 150 rpm, with 20 FPU:40 IU and Saccharomyces cerevisiae IR2T9 thermotolerant at 2.4 g/L.In SSF the experimental ethanol yield was 99%, based on pretreated material.