BioChem - DOS

Comparative material balances around pretreatment technologies for the conversion of switchgrass to soluble sugars

Bioresource technology : biomass, bioenergy, biowastes, conversion technologies, biotransformations, production technologies

Garlock, Rebecca J.; Balan, Venkatesh; Dale, Bruce E.; Ramesh Pallapolu, V.; Lee, Y.Y.; Kim, Youngmi; Mosier, Nathan S.; Ladisch, Michael R.; Holtzapple, Mark T.; Falls, Matthew; Sierra-Ramirez, Rocio; Shi, Jian; Ebrik, Mirvat A.; Redmond, Tim; Yang, Bin; Wyman, Charles E.; Donohoe, Bryon S.; Vinzant, Todd B.; Elander, Richard T.; Hames, Bonnie; Thomas, Steve; Warner, Ryan E.

<P><B>Highlights</B></P><P>&#x025BA; Material balances improve comparisons of different lignocellulosic pretreatment methods. &#x025BA; Pretreatment pH strongly effects solubilization and degradation of cell wall components. &#x025BA; Highest glucose yields were from high-temp, short-time or low-temp, long-time pretreatments. &#x025BA; Low pH &ndash; high temp pretreatments can have significant xylose degradation, increasing with time.</P> <P><B>Abstract</B></P><P>For this project, six chemical pretreatments were compared for the Consortium for Applied Fundamentals and Innovation (CAFI): ammonia fiber expansion (AFEX), dilute sulfuric acid (DA), lime, liquid hot water (LHW), soaking in aqueous ammonia (SAA), and sulfur dioxide (SO<SUB>2</SUB>). For each pretreatment, a material balance was analyzed around the pretreatment, optional post-washing step, and enzymatic hydrolysis of Dacotah switchgrass.</P><P>All pretreatments+enzymatic hydrolysis solubilized over two-thirds of the available glucan and xylan. Lime, post-washed LHW, and SO<SUB>2</SUB> achieved >83% total glucose yields. Lime, post-washed AFEX, and DA achieved >83% total xylose yields. Alkaline pretreatments, except AFEX, solubilized the most lignin and a portion of the xylan as xylo-oligomers. As pretreatment pH decreased, total solubilized xylan and released monomeric xylose increased. Low temperature-long time or high temperature-short time pretreatments are necessary for high glucose release from late-harvest Dacotah switchgrass but high temperatures may cause xylose degradation.</P>

2011

0960-8524

102

24

pp.11063-11071

10.1016/j.biortech.2011.04.002

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART57906615

Cellulosic ethanol; Enzymatic hydrolysis; Material balance; Pretreatment; Switchgrass