Optimisation of steam pretreatment of SO2-impregnated mixed softwoods for ethanol production

✍ Scribed by Kerstin Stenberg; Charlotte Tengborg; Mats Galbe; Guido Zacchi

• Publisher: Wiley (John Wiley & Sons)
• Year: 1998
• Tongue: English
• Weight: 672 KB
• Volume: 71
• Category: Article
• ISSN: 0268-2575
• DOI: 10.1002/(sici)1097-4660(199804)71:4<299::aid-jctb858>3.0.co;2-z

✦ Synopsis

Pretreatment of mixed softwoods with impregnation and steam SO 2 for production of ethanol has been investigated. The optimal conditions, both for sugar yield and ethanol yield, to assess the e †ect of inhibitors formed in the pretreatment, have been determined. The parameters investigated were : con-SO 2 centration (1È6% (w/w) dry matter), temperature (190È230¡C) and residence time (2È15 min). After pretreatment, the material was separated into a solid residue and a Ðltrate. The solid residue was enzymatically hydrolysed with 2% dry matter (w/w). To investigate fermentability, the hydrolysed Ðltrate was fermented using Saccharomyces cerevisiae. The e †ects of the di †erent parameters are described by response-surface modelling. The highest experimental sugar yield of 42É1 g per 100 g dry matter was obtained at 210¡C and 5É5 min residence time. Although the fermentabilities were good for all Ðltrates with yields greater than 90% of the yield obtained in a pure glucose reference solution, the pretreatment has a clear inÑuence on the ethanol production rate.

1998 SCI (