The effect of biomass moisture content on bioethanol yields from steam pretreated switchgrass and sugarcane bagasse.

This study aimed to determine the effect of moisture content of three different feedstocks on overall ethanol yield. Switchgrass and sugarcane bagasse from two sources were either soaked in water (∼80% moisture) or left dry (∼12% moisture), and half each of these were impregnated with 3%w/w SO(2) and all were steam pretreated. The twelve resulting substrates were compared based on overall sugar recovery after pretreatment, cellulose conversion following enzymatic hydrolysis, and ethanol yield following simultaneous saccharification and fermentation. The overall ethanol yield after simultaneous saccharification and fermentation of hexoses was 18-28% higher in samples that were soaked prior to SO(2) addition than in SO(2)-catalyzed samples that were not soaked. In samples that were uncatalyzed, soaking made little difference, indicating that the positive effect of increased moisture content may be related to increased permeability of the biomass to SO(2).

[1]  J N Saddler,et al.  Steam‐explosion pretreatment of wood: Effect of chip size, acid, moisture content and pressure drop , 1986, Biotechnology and bioengineering.

[2]  J. Scurlock,et al.  The development and current status of perennial rhizomatous grasses as energy crops in the US and Europe , 2003 .

[3]  Juan E. Morinelly,et al.  Effects of dilute acid pretreatment conditions on enzymatic hydrolysis monomer and oligomer sugar yields for aspen, balsam, and switchgrass. , 2010, Bioresource technology.

[4]  T. Vuorinen,et al.  Impact of drying on wood ultrastructure observed by deuterium exchange and photoacoustic FT-IR spectroscopy. , 2010, Biomacromolecules.

[5]  I. Cullis,et al.  Effect of initial moisture content and chip size on the bioconversion efficiency of softwood lignocellulosics , 2004, Biotechnology and bioengineering.

[6]  C. Cardona,et al.  Production of bioethanol from sugarcane bagasse: Status and perspectives. , 2010, Bioresource technology.

[7]  Mohammed Moniruzzaman,et al.  Enzymatic hydrolysis of high-moisture corn fiber pretreated by afex and recovery and recycling of the enzyme complex , 1997 .

[8]  R. Ruiz,et al.  Determination of Sugars, Byproducts, and Degradation Products in Liquid Fraction Process Samples , 2008 .

[9]  N. el. Bassam,et al.  Energy Plant Species : Their Use and Impact on Environment and Development , 1998 .

[10]  S. Mansfield,et al.  Tolerance and adaptation of ethanologenic yeasts to lignocellulosic inhibitory compounds , 2006, Biotechnology and bioengineering.

[11]  J. Saddler,et al.  Acid‐catalyzed steam pretreatment of lodgepole pine and subsequent enzymatic hydrolysis and fermentation to ethanol , 2007, Biotechnology and bioengineering.

[12]  M. Galbe,et al.  SO2-catalyzed steam pretreatment and fermentation of enzymatically hydrolyzed sugarcane bagasse , 2010 .

[13]  J. Saddler,et al.  The characterization of pretreated lignocellulosic substrates prior to enzymatic hydrolysis, part 1: A modified Simons' staining technique , 2008, Biotechnology progress.

[14]  J. Saddler,et al.  Substrate and Enzyme Characteristics that Limit Cellulose Hydrolysis , 1999, Biotechnology progress.

[15]  B. Hahn-Hägerdal,et al.  Isolation and characterization of acetic acid-tolerant galactose-fermenting strains of Saccharomyces cerevisiae from a spent sulfite liquor fermentation plant , 1992, Applied and environmental microbiology.

[16]  Carlos Ricardo Soccol,et al.  Bioethanol from lignocelluloses: Status and perspectives in Brazil. , 2010, Bioresource technology.

[17]  J. Saddler,et al.  Influence of xylan on the enzymatic hydrolysis of steam‐pretreated corn stover and hybrid poplar , 2009, Biotechnology progress.

[18]  M. Galbe,et al.  Steam pretreatment of Salix with and without SO2 impregnation for production of bioethanol , 2005, Applied biochemistry and biotechnology.

[19]  H. Krässig,et al.  Cellulose : structure, accessibility, and reactivity , 1993 .

[20]  M. H. Gil,et al.  Hornification—its origin and interpretation in wood pulps , 2004, Wood Science and Technology.