The deliverables of the Action are directly related to the respective objectives.
Collaborative research work was conducted (and continues after the end of the Action) on the topics of biomass pretreatment and (bio)catalytic valorization of hemicellulose and lignin streams, either in the form of “wastes/by-products” or as selectively isolated/recovered fractions.
Several methodologies have been developed and further optimized within the frame of the Action, and this can be justified by the published results in high impact referred journals as well as presentations in the Workshops and meetings (please see relevant places in the Action website: http://www.fp1306.com). Some of them have the potential of reaching an industrial production scale, but this needs further verification and can be the subject of dedicated R&D funded projects or confidential contracts between academia and industry. Still, the output and results generated by the collaborative work within this Action has certainly advanced the potential technologies one step further.
For the shake of completeness, examples of the studied/optimized methods are described below (with more details given above in the respective Objectives).
A variety of mechanical, physical and chemical pretreatment methods, and combinations thereof, have been studied/optimized utilizing the knowledge that was available within the Action, as well as the specific expertise of the various collaborating groups. Specific examples of selective pretreatment/fractionation methods, as also described above in more detail in the respective Objective, include:
- - Hydrothermal (HWE, hot water extraction) pretreatment of biomass for selective removal of hemicellulose
- - Steam explosion pretreatment of biomass (in comparison to HWE)
- - Organosolv and hybrid organosolv steam explosion pretreatment of selective fractionation (recovery of lignin)
- - “Lignin-first approach” which combines the features of an organosolv process with those of reductive catalytic fractionation by the simultaneous use of an appropriate catalyst at the stage of organosolv (pre)treatment
- - Physicochemical pretreatment and fractionation of birch outer bark for the valorization of ‘oleochemicals’ and the additional ‘active’ ingredients
With regard to the down-stream valorization of hemicellulose and lignin, the following catalytic processes have been studied and developed/optimized (more details are given in the respective Objectives above):
- - Novel efficient dehydration of biomass using alternative catalytic technologies towards a green avenue for the production of furfural
- - High-throughput screening of heterogeneous hydrogenation catalysts for the conversion of furfural to bio-based fuel components (2-MF, 2-MTHF) – minimization of H2 use via catalytic transfer hydrogenation
- - Catalytic condensation of furans – ketones and hydrodeoxygenation of derived condensates for fuel production
- - Catalytic valorization of levulinic acid: Green synthesis of γ-valerolactone (GVL) via methyl levulinate hydrogenation
- - Valorization of lignin by catalytic hydrogenation/hydrogenolysis in liquid phase systems by the use of hydrogen donor solvents (transfer hydrogenation)
- - Catalytic pyrolysis of various lignin streams towards upgraded bio-oil for fuels or high value aromatics and alkyl-phenols for polymer production
- - Nano-engineered photocatalysts and respective process schemes for lignin-based model molecules upgrading
- - Engineering Enzymatic Specificity of Ligninolytic Enzymes
- - Production of polymers and carbon Fibers from technical lignins
For all studied processes and reactions, focus has been placed on the improvement of known catalyst types or the development of new catalytic formulations, with tailored properties (i.e. zeolites, metal (nano)oxides, carbon-based catalysts, etc.). In addition, alternative reaction media/solvents and reactors have been utilized (such as microwave batch and continuous flow systems).
Techno-economic assessment and Life cycle analysis (LCA) of various processes has been considered, emphasizing on the production of aromatics and phenols via catalytic fast pyrolysis of lignin.