Hits:

Indexed by:期刊论文

Date of Publication:2019-04-01

Journal:JOURNAL OF ENERGY CHEMISTRY

Included Journals:SCIE

Volume:31

Page Number:39-45

ISSN No.:2095-4956

Key Words:Lignocellulose; scCO(2) pretreatment; Enzymatic hydrolysis; Sugar yield; Moisture content

Abstract:Various agricultural crop residues including corn stover, corn cob, and sorghum stalk with a moisture content of 75 wt% were subjected to a long pretreatment (12-60 h) with supercritical CO2 (scCO(2)), at low temperature (50-80 degrees C) and a pressure of 17.5-25.0 MPa. The sugar yields from the enzymatic hydrolysis (EH) of the pretreated samples were as much as three- to fourfold greater than those afforded by the raw materials. However, when pretreatment was conducted within a short time (e.g. 0.5 h), as previously reported in the literature, only a slight increase in the EH sugar yields was observed. The proposed scCO(2) pretreatment mechanism demonstrated the role of moisture in the system. Wetting, softening, and swelling were observed to mainly affect the lignocellulose when a suitable amount of water was added. Finally, the samples were analysed by X-ray diffraction and scanning electron microscopy, before and after pretreatment, to investigate the changes in the microscopic structure of the biomass. (C) 2018 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.