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- Geddes, C. C., et al.
(författare)
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Optimizing the saccharification of sugar cane bagasse using dilute phosphoric acid followed by fungal cellulases
- 2010
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Ingår i: Bioresource Technology. - : Elsevier BV. - 1873-2976 .- 0960-8524. ; 101:6, s. 1851-1857
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Tidskriftsartikel (refereegranskat)abstract
- A low level of phosphoric acid (1% w/w on dry bagasse basis, 160 degrees C and above, 10 min) was shown to effectively hydrolyze the hemicellulose in sugar cane bagasse into monomers with minimal side reactions and to serve as an effective pre-treatment for the enzymatic hydrolysis of cellulose. Up to 45% of the remaining water-insoluble solids (WIS) was digested to sugar monomers by a low concentration of Biocellulase W (0.5 filter paper unit/g WIS) supplemented with beta-glucosidase, although much higher levels of cellulase (100-fold) were required for complete hydrolysis. After neutralization and nutrient addition, phosphoric acid syrups of hemicellulose sugars were fermented by ethanologenic Escherichia coli LY160 without further purification. Fermentation of these syrups was preceded by a lag that increased with increased pre-treatment temperature. Further improvements in organisms and optimization of steam treatments may allow the co-fermentation of sugars derived from hemicellulose and cellulose, eliminating need for liquid-solid separation, sugar purification, and separate fermentations. (C) 2009 Elsevier Ltd. All rights reserved.
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| 2. |
- Robledo-Abad, Carmenza, et al.
(författare)
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Bioenergy production and sustainable development: science base for policy-making remains limited
- 2017
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Ingår i: Global Change Biology Bioenergy. - : Wiley. - 1757-1693 .- 1757-1707. ; 9:3, s. 541-556
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Tidskriftsartikel (refereegranskat)abstract
- The possibility of using bioenergy as a climate change mitigation measure has sparked a discussion of whether and how bioenergy production contributes to sustainable development. We undertook a systematic review of the scientific literature to illuminate this relationship and found a limited scientific basis for policy-making. Our results indicate that knowledge on the sustainable development impacts of bioenergy production is concentrated in a few well-studied countries, focuses on environmental and economic impacts, and mostly relates to dedicated agricultural biomass plantations. The scope and methodological approaches in studies differ widely and only a small share of the studies sufficiently reports on context and/or baseline conditions, which makes it difficult to get a general understanding of the attribution of impacts. Nevertheless we identified regional patterns of positive or negative impacts for all categories – environmental, economic, institutional, social and technological. In general, economic and technological impacts were more frequently reported as positive, while social and environmental impacts were more frequently reported as negative (with the exception of impacts on direct substitution of GHG emission from fossil fuel). More focused and transparent research is needed to validate these patterns and develop a strong science underpinning for establishing policies and governance agreements that prevent/mitigate negative and promote positive impacts from bioenergy production.
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