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Biochemical conversion and process efficiency for advanced biofuels
One of the work packages of BECOOL focused on increasing the energy efficiency of biochemical pathways to produce cellulosic ethanol from the diverse range of feedstocks studied by the project. This included the optimization of a multi-step process encompassing biomass pre-treatment and enzymatic hydrolysis to obtain C5 and C6 sugars followed by the fermentation of cellulosic and hemicellulosic sugars into alcohols (ethanol and butanol). Increasing both the yields and the fermentability of C5 and C6 sugars were the key objectives of this task. For this scope, the FABIOLATM organosolv fractionation technology developed by TNO in the Netherlands was used for the pretreatment of biomass, which integrated
with enzymatic hydrolysis, produces C5 and C6 sugars streams and high-quality lignin. Wageningen University performed the research activities on the fermentation of C5 and C6 sugars to ethanol and butanol. The process was applied to a range of biomass types including agricultural residues, forestry residues and energy crops, containing significant amounts of non-lignocellulosic components (minerals and extractives) that can interfere with the fractionation process and affect the final yield of fermentable sugars. For this reason, TNO implemented a pre-extraction process in order to enhance the robustness of the fractionation and its capability to treat the whole range of biomass feedstock.
Fig 42. Scheme of the FABIOLATM biorefinery process for lignin and fermentable sugars production from lignocelluloses. Source: TNO.
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