Acetone–Butanol–Ethanol Fermentation of Non-detoxified Dilute Acid extracted Hemicellulosic Hydrolysate from the Short-rotation Coppice Salix schwerinii E. Wolf

Suvi Kuittinen, Ming Yang, Erik Kaipiainen, Aki Villa, Markku Keinänen, Jouko Vepsäläinen, Ari Pappinen

Abstract


The dilute acid-catalyzed extraction of hemicellulosic monosaccharides from the short-rotation coppice Salix schwerinii E. Wolf was optimized to find a balance between the yields of fermentable monosaccharides and sugar degradation products for non-detoxified acetone-butanol-ethanol fermentation with Clostridium acetobutylicum. At the same time, the cellulosic and lignin fractions were kept as intact as possible for further refining. The highest xylose and glucose yields in the liquid prehydrolysate were 65% and 9.45% of their respective original content at a combined severity of 2.29. Increased concentrations of glucose and sugar degradation products in the liquid prehydrolysates were detected with an increasing pretreatment temperature and combined severity, while the acid-insoluble lignin remained stable. During the fermentation of the non-detoxified liquid prehydrolysate with grain starch as the supplement, 66% of the xylose was utilized, and the butanol and acetone-butanol-ethanol yields were 0.22 g/g and 0.35 g/g monosaccharides, respectively, in the fermentation medium. The results suggested that the hemicellulose in S. schwerinii can be separately extracted as a side stream and utilized for butanol fermentation with starch-based materials without a separate detoxification stage.

Keywords


Short rotation coppice; Salix schwerinii; Pretreatment; Acetone-butanol-ethanol fermentation; Clostridium acetobutylicum; Biorefining

Full Text: PDF

Welcome to BioResources! This online, peer-reviewed journal is devoted to the science and engineering of biomaterials and chemicals from lignocellulosic sources for new end uses and new capabilities. The editors of BioResources would be very happy to assist you during the process of submitting or reviewing articles. Please note that logging in is required in order to submit or review articles. Martin A. Hubbe, (919) 513-3022, hubbe@ncsu.edu; Lucian A. Lucia, (919) 515-7707, lucian.lucia@gmail.com URLs: bioresourcesjournal.com; http://ncsu.edu/bioresources ISSN: 1930-2126