Pretreatment as the crucial step for a cellulosic ethanol biorefinery: testing the efficiency of wet explosion on different types of biomass.

The efficiency of wet explosion applied as modified dilute acid pretreatment at previously identified reference conditions (150°C, 0.3% H(2)SO(4), 15 min) was investigated on lucerne, ryegrass, fescue grass, cocksfoot grass, rye fescue, forage grass, and wheat straw in order to identify their potential as feedstock for cellulosic bioethanol production. After pretreatment, cellulose recovery was more than 95% for all biomass while enzymatic convertibility of cellulose ranged from 40% to 80%. Lower enzymatic conversion of cellulose was correlated with higher lignin content of the biomass. Hemicellulose recovery was 81-91% with a final pentose yield of 65-85%. Cocksfoot grass and wheat straw had the highest bioethanol potential of 292 and 308 L/ton DM, respectively. Overall efficiencies were higher than 68% for cocksfoot grass harvested in August, fescue grass, wheat straw, and forage grass while efficiencies were lower than 61% for the other tested biomass resources, making further adjustment of the process parameters necessary.

[1]  B. Ahring,et al.  Hydrolysis of Miscanthus for bioethanol production using dilute acid presoaking combined with wet explosion pre-treatment and enzymatic treatment. , 2008, Bioresource technology.

[2]  C. Wyman,et al.  Features of promising technologies for pretreatment of lignocellulosic biomass. , 2005, Bioresource technology.

[3]  Michael Knauf,et al.  Lignocellulosic biomass processing: a perspective. , 2004 .

[4]  Min Zhang,et al.  Advanced Bioethanol Production Technologies: A Perspective , 1997 .

[5]  B. Dale,et al.  Sessions 3 and 8: Pretreatment and Biomass Recalcitrance: Fundamentals and Progress , 2009, Applied biochemistry and biotechnology.

[6]  B. Saha,et al.  Lignocellulose biodegradation and applications in biotechnology , 2004 .

[7]  Anne Belinda Thomsen,et al.  Preliminary results on optimization of pilot scale pretreatment of wheat straw used in coproduction of bioethanol and electricity , 2006, Applied biochemistry and biotechnology.

[8]  M. Galbe,et al.  Steam pretreatment of H(2)SO(4)-impregnated Salix for the production of bioethanol. , 2008, Bioresource technology.

[9]  Mette Hedegaard Thomsen,et al.  Optimization of hydrothermal pretreatment of wheat straw for production of bioethanol at low water consumption without addition of chemicals , 2009 .

[10]  Xiaoru Hou,et al.  Enzymatic Hydrolysis and Ethanol Fermentation of High Dry Matter Wet-Exploded Wheat Straw at Low Enzyme Loading , 2008, Applied biochemistry and biotechnology.

[11]  Ratna R. Sharma-Shivappa,et al.  Saccharification and Fermentation of Dilute-Acid-Pretreated Freeze-Dried Switchgrass† , 2009 .

[12]  Irini Angelidaki,et al.  Optimization of H2SO4-catalyzed hydrothermal pretreatment of rapeseed straw for bioconversion to ethanol: focusing on pretreatment at high solids content. , 2009, Bioresource technology.

[13]  K. Réczey,et al.  Pretreatment of corn stover using wet oxidation to enhance enzymatic digestibility , 2003, Applied biochemistry and biotechnology.

[14]  Mohammad J. Taherzadeh,et al.  Ethanol production from dilute-acid pretreated rice straw by simultaneous saccharification and fermentation with Mucor indicus, Rhizopus oryzae, and Saccharomyces cerevisiae , 2006 .

[15]  B. Ahring,et al.  Coproduction of bioethanol with other biofuels. , 2007, Advances in biochemical engineering/biotechnology.

[16]  Anne Belinda Thomsen,et al.  Wet oxidation as a pretreatment method for enhancing the enzymatic convertibility of sugarcane bagasse , 2007 .

[17]  G. Zeeman,et al.  Pretreatments to enhance the digestibility of lignocellulosic biomass. , 2009, Bioresource technology.

[18]  Bärbel Hahn-Hägerdal,et al.  Fermentation of lignocellulosic hydrolysates. II: inhibitors and mechanisms of inhibition. , 2000 .

[19]  Lee R. Lynd,et al.  Overview and evaluation of fuel ethanol from cellulosic biomass , 1996 .

[20]  M. Galbe,et al.  A review of the production of ethanol from softwood , 2002, Applied Microbiology and Biotechnology.

[21]  B. Ahring,et al.  Inhibition of ethanol-producing yeast and bacteria by degradation products produced during pre-treatment of biomass , 2004, Applied Microbiology and Biotechnology.