Directly convert lignocellulosic biomass to H2 without pretreatment and added cellulase by two-stage fermentation in semi-continuous modes

Jun Hu, Wen Cao and Liejin Guo

Renewable Energy, 2021, vol. 170, issue C, 866-874

Abstract: Cost-competitive production of lignocellulosic H2 using biological methods is limited by energy-intensive pretreatments and expensive cellulase hydrolysis. Here we report stable two-stage fermentation to convert unpretreated energy sorghum without added cellulase to H2, where Clostridium thermocellum was fed semi-continuously with 20 g/L sorghum in the first stage and then Rhodobacter sphaeroides consumed the effluent wastes in the second stage to achieve residence times (RTs) of 60, 48, and 24 h. Glutamic acid was the preferred nitrogen source for coordinating the two-stage, two-organism fermentation. 25.0 ± 1.1 mL-H2/day in consolidated bioprocessing stage and 133.0 ± 1.5 mL-H2/day in photofermentation stage were obtained for 200 mL cultures at RT 48 h. Propionate is the main product accumulated, with cellobiose, xylose, arabinose, formate, acetate and ethanol also observed in the effluent wastes, which were degraded effectively by Rhodobacter sphaeroides with COD removal of 72.6%. These results provide references for developing low-cost H2 production from lignocellulose.

Keywords: Lignocellulose; Clostridium thermocellum; Rhodobacter sphaeroides; Two-stage fermentation; Consolidated bioprocessing (search for similar items in EconPapers)
Date: 2021
References: Add references at CitEc
Citations: View citations in EconPapers (3)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0960148121002305
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:renene:v:170:y:2021:i:c:p:866-874

DOI: 10.1016/j.renene.2021.02.062

Access Statistics for this article

Renewable Energy is currently edited by Soteris A. Kalogirou and Paul Christodoulides

More articles in Renewable Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().