Sunday, May 3, 2009
3-73
A catalyzed wet-explosion of wheat straw
Troels Hilstrøm, Hanne R. Sørensen, and Birgitte K. Ahring. BioGasol, Lautrupvang 2A, Ballerup, DK-2750, Denmark
The individual and interactive effect of different pretreatment conditions on the release of arabinose, glucose, xylose, and acetic acid from wheat straw during pretreatment and on dehydration of pentoses to 2-furaldehyde, and hexoses to 5-hydroxymethyl-2-furaldehyde (HMF) during pretreatment of wheat straw, were evaluated in a three-factor central composite design template. The template comprised 17 different combinations of temperature (-1, 0, 1), residence time (-1, 0, 1), and H2SO4 concentration (-1, 0, 1) with three center points. In all pretreatments, a fixed amount of air was used as oxidizing agent.
H2SO4-catalyzed wet-explosion of wheat straw was optimized in such a way, that the right combination of temperature, residence time, and sulfuric acid concentration in a wet-explosion process resulted in optimal recovery of the heteroxylan-derived sugars (arabinose, and xylose), ideally in a monomeric form, and that the formations of inhibitors (primarily 2- furaldehyde and HMF) were minimized. In addition, enzymatic hydrolysis with commercial available cellulase preparations was used to select the optimal pretreatment condition for wheat straw.