title: Multi-level dissolution and hydrolysis of lignocellulosic waste with a semi-flow hydrothermal system.
abstract: The hydrothermal process is efficient in lignocellulosic conversion and is beneficial to potential bioethanol production. In batch- and flow-type processes, concurrent dissolution and hydrolysis of lignocellulose result in product loss and inhibitory intermediates. Therefore, multi-level hydrothermal conversion of corn stalks was implemented with a semi-flow system to provide different residence times to undissolved compounds and facilitate dissolution or hydrolysis at respective optimal conditions. First-stage dissolution dissolved amorphous hemicellulose and lignin at 195-200°C. Xylan, acid soluble lignin, and part of Klason lignin were dissolved without affecting glucan. In second-stage dissolution, the crystallinity of the undissolved materials suddenly decreased at 245-250°C. The cellulose dissolution ratio was higher than 75%. Soluble sugars were obtained after the hydrolysis of dissolved cellulose at 280°C. The results provide significant information on the multi-level hydrothermal process and its potential applications for recovering valuable chemicals from lignocellulosic waste.
authors.affiliation: School of Environment, Beijing Normal University, Beijing 100875, China. Electronic address: yanzhao@bnu.edu.cn.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: School of Environment, Beijing Normal University, Beijing 100875, China.
authors.forename: Haobo
authors.initials: H
authors.lastname: Tan
authors.affiliation: School of Environment, Beijing Normal University, Beijing 100875, China.
authors.forename: Yingjie
authors.initials: Y
authors.lastname: Xu
authors.affiliation: School of Environment, Beijing Normal University, Beijing 100875, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zou
mesh_terms: D003460:Crystallization; D006868:Hydrolysis; D008031:Lignin / Q000737:chemistry*; D012212:Rheology / Q000379:methods*; D012995:Solubility; D013696:Temperature; D014866:Waste Products; D014867:Water / Q000737:chemistry*; D003313:Zea mays / Q000737:chemistry
chemical_list: D014866:Waste Products; D014867:Water; C036909:lignocellulose; D008031:Lignin
keywords: Cellulose hydrolysis; Hydrothermal process; Lignocellulosic waste; Multi-level dissolution; Semi-flow reaction system