Optimization of alkali soaking and extrusion pretreatment of prairie cord grass for maximum sugar recovery by enzymatic hydrolysis

Application of Response Surface Methodology to Optimize Alkali Concentration, Corn Stover Particle Size, and Extruder Parameters for Maximum Sugar Recovery

“…No glycerol was found in any of the pretreatment combinations in contrary to the results reported by Karunanithy and Muthukumarappan (Karunanithy & Muthukumarappan, 2010c, 2011a, 2011b, 2011c, 2010a, 2010b.In addition, no furfural and HMF were found in any of the pretreated corn stover samples. The possible reason could be short residence time and no acidic conditions during pretreatment as compared most of the pretreatment methods listed in the table.…”

“…Solutions for optimal and validation conditions (assumption a thumb rule is 50% of the glucose will be converted into ethanol during fermentation with an efficiency of 90%).This optimization study revealed that a larger p a r t i c l e s i z e ( 8 m m ) c o u l d b e u s e d f o r b i ofuels production; thereby the biomass size reduction energy cost can be saved to a greater extent. Although the optimum pretreatment condition differed from corn stover, similar sugar recovery was reported for switchgrass and prairie cord grass (Karunanithy & Muthukumarappan, 2011b, 2011c. The biomass digestibility depends on the specific types of phenolic acids that constitute the non-core lignin of lignocellulosic biomass (Jung & Deetz, 1993).…”

“…An extruder has the ability to provide high shear, rapid heat transfer, effective and rapid mixing in a short residence time, as well as adaptability to many different processes -all in a continuous process. A few extrusion pretreatments (Dale et al, 1999;de Virje et al, 2002;Karunanithy et al, 2008;Karunanithy & Muthukumarappan, 2010a, 2010b, 2010c, 2011a, 2011b, 2011c Lee et al, 2009;Muthukumarappan & Julson, 2007 ) showed a significant improvement on sugar recovery from corn stover, switchgrass, miscanthus, prairie cord grass, big bluestem, and Douglas fir through enzymatic hydrolysis. Potential fermentation inhibitors such as furfural and HMF were not reported in any of the above studies.…”

NaOH Pretreatment of Wheat Straw at a Mesophilic Temperature: Effect on Hydrolysis and Loss of Organic Carbon

“…Hemicellulose (%) = NDF (%)-ADF (%) (2) Cellulose (%) = ADF (%)-ADL (%) (3) Lignin (%) = ADL (%)-Ash (%) (4) Microscope Observation A scanning electron microscope (SEM, S-4800, Hitachi, Japan) was used to visualize the surficial differences between untreated and pretreated wheat straw at a magnification of 500×. The wheat straw was metalized with a thin layer of gold in a sputter coater polaron (E-1045, Hitachi, Japan) to ensure the conductivity of its observation.…”

Pre-treatment of sugarcane bagasse with a combination of sodium hydroxide and lime for improving the ruminal degradability: optimization of process parameters using response surface methodology

“…Optimization of pre-treatment conditions is a key step in development of an efficient and cost-effective pre-treatment (Karunanithy & Muthukumarappan 2011). Response surface methodology (RSM), with successful application to lignocellulose pre-treatment (Velmurugan & Muthukumar 2012;Rawat et al 2013), is an effective optimization tool with which many operating variables along with their interactive effects on a desired response and/or responses can be identified with few observations (Karunanithy & Muthukumarappan 2011).…”