Second generation bioethanol from Eucalyptus globulus Labill and Nothofagus pumilio: ionic liquid pretreatment boosts the yields

María Elena Lienqueo, María Cristina Ravanal, Ricardo Pezoa Conte, Victoria Cortínez, Loreto Martínez, Tomas Niklitschek, Oriana Salazar, René Carmona, Alejandro García, Sari Hyvärinen, Päivi Mäki-Arvela, Jyri-Pekka Mikkola

Research output: Contribution to journalArticleScientificpeer-review

24 Citations (Scopus)

Abstract

The depletion of petroleum reserves and the high level of pollution caused by fossil fuels have led to enhancing renewable energy and fuel production from biomass. Eucalyptus globulus and Nothofagus pumilio residues could constitute an interesting source of biomass for second generation biofuel production. Lenga residues were pretreated with the ionic liquid (IL) 1-N-ethyl-3-methylimidazolium chloride (C2mimCl), followed by subsequent fermentation using both the strategy of Simultaneous Saccharification and Fermentation (SSF) as well as Separate Hydrolysis and Fermentation (SHF). The SHF process yielded 0.134 g ethanol/g glucose (26.3 wt-% of the theoretical yield) compared to the SSF process which yielded 0.173 g ethanol/g glucose (33.9 wt-% of the theoretical yield) within the first 24 h of fermentation. In case of Eucalyptus residues, another IL, 1-N-ethyl-3-methylimidazolium acetate (C2minOAc) was applied. The SSF process was applied for a period of three days. As a result, 3.7 g ethanol/L (corresponding to a yield of 0.19 g of ethanol/g of glucose or 38.0 wt-% of the theoretical maximum) was obtained at 72 h. When fresh Lenga and Eucalyptus residues were fermented without any pretreatment, the SSF process yielded 0.017 and 0.002 g of ethanol/g of glucose, respectively (3.33 wt-% and 0.48 wt-% of the theoretical maximum, respectively). Thus, the pretreatment procedures resulted in a significant increase in ethanol production, therefore justifying the need of pretreatment prior to the co-enzyme hydrolysis and fermentation for this type of biomass. Further, the combination of IL pretreatment and use of SSF process demonstrated the high potential for bioethanol production from Lenga and Eucalyptus residues. Nevertheless, further improvement by optimization of operational conditions is required to maximize the ethanol yield.
Original languageUndefined/Unknown
Pages (from-to)148–155
JournalIndustrial Crops and Products
Volume80
DOIs
Publication statusPublished - 2016
MoE publication typeA1 Journal article-refereed

Cite this