title: Sequential dilute acid and alkali pretreatment of corn stover: sugar recovery efficiency and structural characterization.
abstract: The objectives of this study were to explore the feasibility of applying sequential dilute acid and alkali pretreatment into the hydrolysis of corn stover and to elucidate the effects of structural changes in the biomass on its enzymatic digestibility. H2SO4 used in the first step selectively hydrolyzed 74.6-77.3% of xylan and NaOH used in the second step removed 85.9-89.4% of lignin, from the raw corn stover. Compared to single dilute acid pretreatment, the proposed combined pretreatment minimized the generation of byproducts such as acetic acid, furfural and hydroxymethylfurfural in the hydrolysates, and enhanced the enzymatic hydrolysis of the solid residue. The changes in the structural features (porosity, morphology, and crystallinity) of the solid residue were strongly correlated with the enhancement of enzymatic digestibility. The overall glucose and xylose yields finally obtained after enzymatic hydrolysis reached 89.1-97.9% and 71.0-75.9%, respectively.
authors.affiliation: School of Environmental Science and Engineering, Pohang University of Science and Technology, San 31, Hyoja-dong, Pohang 790-784, South Korea.
authors.forename: Jae Won
authors.initials: JW
authors.lastname: Lee
authors.affiliation: Bioenergy Research Center, Pohang University of Science and Technology, San 31, Hyoja-dong, Pohang 790-784, South Korea.
authors.forename: Ji Young
authors.initials: JY
authors.lastname: Kim
authors.affiliation: School of Environmental Science and Engineering, Pohang University of Science and Technology, San 31, Hyoja-dong, Pohang 790-784, South Korea.
authors.forename: Hyun Min
authors.initials: HM
authors.lastname: Jang
authors.affiliation: Department of Chemical Engineering, Keimyung University, 1095 Dalgubeoldaero, Dalseo-Gu, Daegu 704-701, South Korea. Electronic address: mwlee@kmu.ac.kr.
authors.forename: Min Woo
authors.initials: MW
authors.lastname: Lee
authors.affiliation: Division of Advanced Nuclear Engineering, School of Environmental Science and Engineering, Department of Chemical Engineering, Pohang University of Science and Technology, San 31, Hyoja-dong, Pohang 790-784, South Korea. Electronic address: jmpark@postech.ac.kr.
authors.forename: Jong Moon
authors.initials: JM
authors.lastname: Park
mesh_terms: D000468:Alkalies / Q000737:chemistry; D018533:Biomass; D001709:Biotechnology / Q000379:methods; D005662:Furaldehyde / Q000031:analogs & derivatives / Q000737:chemistry; D005947:Glucose / Q000737:chemistry*; D006868:Hydrolysis; D008031:Lignin / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D017550:Spectroscopy, Fourier Transform Infrared; D013464:Sulfuric Acids / Q000737:chemistry; D014990:Xylans / Q000737:chemistry; D014994:Xylose / Q000737:chemistry*; D003313:Zea mays / Q000737:chemistry*
chemical_list: D000468:Alkalies; D013464:Sulfuric Acids; D014990:Xylans; C008046:5-hydroxymethylfurfural; D008031:Lignin; D014994:Xylose; D005662:Furaldehyde; D005947:Glucose
keywords: Corn stover; Enzymatic hydrolysis; Lignocellulose; Sequential acid–alkali pretreatment; Sugar recovery