Steam explosion pre-treatment of alkali-impregnated lignocelluloses for hemicelluloses extraction and improved digestibility. (December 2019)

• Record Type: Journal Article
• Authors: Mihiretu, Gezahegn T.; Chimphango, Annie F.; Görgens, Johann F.
• Is Part Of: Bioresource technology. Volume 294(2019)
• Publication Date: 2019-12
• Subjects: Xylan extraction -- Alkaline steam explosion pre-treatment -- Sugarcane trash -- Aspen wood -- Lignocellulosic biorefinery; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2019.122121
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: Alkalinized steam explosion pretreatment (ASEPT) was studied in biorefinery setup. Co-production of xylan biopolymers and ethanol was viable under ASEPT conditions. Formation of monomeric sugars and degradation products was effectively minimized. Xylan yield and cellulose digestibility were mainly influenced by temperature. ASEPT appeared more effective on sugarcane trash (SCT) than on aspenwood (AW). Abstract: The application of steam explosion pre-treatment to extract xylan-rich biopolymers from alkali-impregnated lignocelluloses, while simultaneously increasing the enzymatic digestibility of cellulose, was investigated. Steam-enhanced extraction of xylan from sugarcane trash (SCT) and aspen wood (AW) was performed at varying temperatures (176–204 °C) and retention times (3–17 min) after the impregnation of biomass samples with sodium hydroxide at 1:20 (w/w) solid loading ratio. Xylan extraction and cellulose digestibility results were statistically analysed to fix the condition/s for significantly enhanced values. Accordingly, maximum xylan yields of 51 and 24%, and highest cellulose digestibility of 92 and 81%, were attained for SCT and AW respectively following their pre-treatment at 204 °C for 10 min. At this most-severe condition, neither xylose nor furfural – a degradation product from xylose – were observed in the hemicellulose extract, indicating steam explosion pre-treatment with alkali impregnation of lignocelluloses as viable biorefinery approach to co-produce xylan biopolymers and bioethanol.