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Advanced biofuels are produced from renewable resources that comply with stringent sustainability criteria, and lower GHG emissions than fossil fuels. In the BECOOL/BioValue EU-Brazil cooperation project, novel value chains for advanced bioethanol are developed. Second generation (2G) bio-ethanol represents the most important advanced biofuel from sugar streams, but its production costs are higher than those of other fuels, and innovations are needed to improve efficiency and economics of the process. In this work, beech wood pellets were treated using the FABIOLATM technology, an acetone-based low-temperature organosolv fractionation process. This fractionation results in three main product streams: lignin, a high-purity cellulosic pulp and hemicellulose sugars in solution. The cellulosic pulp was enzymatically hydrolysed producing a glucose-rich (C6) stream and the hemicellulose sugar solution (C5) is conditioned for further biological conversion. The C6 and C5 streams obtained were used for fermentation by the yeasts Saccharomyces cerevisiae and Spathaspora passalidarum, respectively. While the C6 stream was readily fermentable, the C5 stream was only fermentable after dilution. Therefore the C5 stream was subjected to detoxification by activated carbon. Detoxified C5 streams showed higher fermentability and the production of bio-ethanol reached approximately 0.3 g bio-ethanol/gram xylose consumed. Fermentation experiments at 10-L scale confirmed the results obtained at laboratory scale. Combining FABIOLATM and detoxification resulted in efficient C6 and C5 utilization for bio-ethanol production., Proceedings of the 30th European Biomass Conference and Exhibition, 9-12 May 2022, Online, pp. 849-850

The aim of the project “More Fuels from Organic Residues” (MOTOR) is to produce advanced biofuels for the transport sectors where electrification or gaseous biofuels will not generate the reduction of their carbon footprint in the short term. In MOTOR, wet lignocellulosic waste streams that do not compete with the food/feed market are used as a feedstock for a smart fermentation process. In the present study, the utilization of paper sludge as substrate for fermentation for production of fuel precursors and subsequent catalytic conversion to fuels at laboratory scale is described. The steps of the process were assessed experimentally, and based on the data generated, a conceptual process is being developed to explore the economic and sustainability aspects of the new value chain for biofuel.. Results show that solubilization of sugars from paper sludge using existing enzyme cocktails is very limited and needs improvement. On the other hand, the catalytic production of fuel from the fermentation products shows promising results in terms of type of products., Proceedings of the 30th European Biomass Conference and Exhibition, 9-12 May 2022, Online, pp. 24-27

Seaweed (or macroalgae) produced sustainably at large scale opens opportunities as source of fuels, chemicals and food. The production does not directly compete with terrestrial food production and may make use of anthropogenic sources of carbon dioxide and nitrogen. Seaweed biomass can be transformed into a suitable substrate for fermentation using a biorefinery approach. In this study the entire process of biofuel production from seaweed is described: starting with cultivation and harvest, the seaweed is dried and cut, enzymatically hydrolysed, demineralized, detoxified, and finally fermented into acetone, butanol, and ethanol (ABE). Juvenile Saccharina latissima was directly seeded on AlgaeTex® nets and cultivated in the North East Atlantic off the west coast of Scotland for 6 months. Sun dried seaweed was hydrolysed with different enzymes, looking for optimal glucose release, solid/liquid ratio, and enzyme load. Using Cellic® CTec2 in combination with alginate lyases, approximately 80% of available glucose was released. The hydrolysis was scaled up to 100 L, using only Cellic® CTec2. Part of the hydrolysate was demineralized using ion-exclusion chromatography, removing over 90% of minerals while recovering 92% of glucose and mannitol. A fraction of the demineralized hydrolysate was additionally detoxified using a hydrophobic resin to remove hydrophobic components to a concentration below detection limit. The three hydrolysates (untreated, demineralized, and demineralized followed by detoxification) were used as substrate for ABE production by a newly developed strain of Clostridium acetobutylicum adapted to grow on S. latissima hydrolysate. Demineralization reduced the lag phase of fermentation from 72 h (untreated) to 24–48 h. Further detoxification of the hydrolysate led to immediate fermentation, resulting in a yield of 0.23 ± 0.02 gABE/gsugar similar to control fermentation in control medium (0.19 gABE/gsugar).