Assessment of organosolv, hydrothermal, and combined organosolv and hydrothermal with enzymatic pretreatment to increase the production of biogas from Napier grass and Napier silage. (January 2022)

• Record Type: Journal Article
• Authors: Jomnonkhaow, Umarin; Sittijunda, Sureewan; Reungsang, Alissara
• Is Part Of: Renewable energy. Volume 181(2022)
• Page Start: 1237
• Page End: 1249
• Publication Date: 2022-01
• Subjects: Chemical pretreatment -- Second generation biomass -- Anaerobic digestion -- Biofuel -- Renewable energy -- Biomass recalcitrance; Renewable energy sources -- Periodicals; Power resources -- Periodicals; Énergies renouvelables -- Périodiques; Ressources énergétiques -- Périodiques; 333.794
• DOI: 10.1016/j.renene.2021.09.099
• Languages: English
• ISSNs: 0960-1481

Abstract

Abstract: The effects of organosolv, hydrothermal, combined organosolv, and hydrothermal processes followed by enzyme pretreatment on Napier grass and silage were evaluated for their efficacy in enhancing methane production. The pretreatment of Napier grass and silage by organosolv followed by enzymatic hydrolysis significantly improved methane yields by 1.9–2.0 times compared with untreated Napier grass and silage. In addition, organosolv-treated Napier grass followed by enzymatic hydrolysis yielded 7.8% more methane (410 mL/g-volatile solidadded (VSadded )) than organosolv-treated silage followed by enzymatic hydrolysis (378 mL/g-VSadded ). Organosolv pretreatment enhanced lignin removal, while hydrothermal pretreatment effectively hydrolyzed hemicellulose. Delignification and reduction of crystallinity during organosolv improve the degradability of Napier grass and silage, resulting in their significantly higher energy recovery of 14.8 and 13.6 kJ/g-VSadded, respectively, which were higher than the energy recovery attained from the hydrothermal process. Highlights: Organosolv pretreatment shows a great impact on the removal of lignin. Cellulose obtained from organosolv pretreatment gave the highest methane yield. Hydrothermal pretreatment is effective in hydrolyzing hemicellulose. The sulfuric acid catalyst showed superior effects on hemicellulose hydrolysis. Prolonged pretreatment time resulted in increased reducing sugar yield.