title: Sulfuric acid pretreatment and enzymatic hydrolysis of photoperiod sensitive sorghum for ethanol production.
abstract: Photoperiod sensitive (PS) sorghum, with high soluble sugar content, high mass yield and high drought tolerance in dryland environments, has great potential for bioethanol production. The effect of diluted sulfuric acid pretreatment on enzymatic hydrolysis was investigated. Hydrolysis efficiency increased from 78.9 to 94.4% as the acid concentration increased from 0.5 to 1.5%. However, the highest total glucose yield (80.3%) occurred at the 1.0% acid condition because of the significant cellulose degradation at the 1.5% concentration. Synchrotron wide-angle X-ray diffraction was used to study changes of the degree of crystallinity. With comparison of cellulosic crystallinity and adjusted cellulosic crystallinity, the crystalline cellulose decreased after low acidic concentration (0.5%) applied, but did not change significantly, as the acid concentration increased. Scanning electron microscopy was also employed to understand how the morphological structure of PS sorghum changed after pretreatment. Under current processing conditions, the total ethanol yield is 74.5% (about 0.2 g ethanol from 1 g PS sorghum). A detail mass balance was also provided.
authors.affiliation: Department of Biological and Agricultural Engineering, Kansas State University, Manhattan, KS 66506, USA.
authors.forename: Feng
authors.initials: F
authors.lastname: Xu
authors.forename: Yong-Cheng
authors.initials: YC
authors.lastname: Shi
authors.forename: Xiaorong
authors.initials: X
authors.lastname: Wu
authors.forename: Karnnalin
authors.initials: K
authors.lastname: Theerarattananoon
authors.forename: Scott
authors.initials: S
authors.lastname: Staggenborg
authors.forename: Donghai
authors.initials: D
authors.lastname: Wang
mesh_terms: D018533:Biomass; D001709:Biotechnology / Q000379:methods*; D002482:Cellulose / Q000737:chemistry; D003460:Crystallization; D000431:Ethanol / Q000737:chemistry; D005285:Fermentation; D006868:Hydrolysis; D008031:Lignin / Q000737:chemistry; D008855:Microscopy, Electron, Scanning / Q000379:methods; D017440:Photoperiod; D045868:Sorghum / Q000737:chemistry / Q000378:metabolism*; D013464:Sulfuric Acids / Q000494:pharmacology*; D017356:Synchrotrons; D013696:Temperature; D014961:X-Ray Diffraction
chemical_list: D013464:Sulfuric Acids; D000431:Ethanol; D002482:Cellulose; D008031:Lignin; C033158:sulfuric acid