Periodic Reporting for period 2 - BIOCTANE (Synergetic integration of BIOteChnology and thermochemical CaTalysis for the cAscade coNvErsion of organic waste to jet-fuel)
Reporting period: 2024-03-01 to 2025-06-30
BIOCTANE project aims to develop a process for the conversion of organic waste materials naturally characterized by a high-water content (e.g. food-waste, organic material from the food processing industry) into sustainable aviation fuels. With the goal to maximize the transfer efficiency of the organic carbon into the respective fuel products, biochemical and thermocatalytic processes will be combined in a robust and efficient cascade process where the complex organic waste streams will be converted to platform chemicals (acetoin and 2,3-Butanediol) that will be later downstream catalytically processed to hydrocarbons compatible with jet-fuel formulations. The wet organic matter inaccessible by the biotechnological conversion steps will be gasified under hydrothermal catalytic conditions to hydrogen (H2) useable as an additional feedstock in the biotechnological conversion steps.
There is a growing demand for alternative sustainable feedstock-based ways to produce jet-fuel. This implies the development of new production chains consisting of the integration of catalytic conversion processes not been connected before and not been analyzed for efficiency improvement and scalability within this specific context. The BIOCTANE project aims to contribute to the development of these demanded new routes, reaching a TRL level of 4. To succeed in the concept proposed in BIOCTANE project, the following aspects need to be developed:
- New strategies for eco-engineering the biological mixed cultures processes towards stabilized and optimized conversion of complex organic waste streams.
- An improved mixotrophic strain for the continuous production of platform chemicals that can be used for further processing into fuel components.
- New robust catalysts producing selectively H2 from wet biomass under hydrothermal conditions.
- New or improved catalysts to address the integration of typically independent reactions into a one-step process for the conversion of platform chemicals into jet-fuel range hydrocarbons.
- A full process that allows elucidating the techno-economic requirements for full market integration.
There is a growing demand for alternative sustainable feedstock-based ways to produce jet-fuel. This implies the development of new production chains consisting of the integration of catalytic conversion processes not been connected before and not been analyzed for efficiency improvement and scalability within this specific context. The BIOCTANE project aims to contribute to the development of these demanded new routes, reaching a TRL level of 4. To succeed in the concept proposed in BIOCTANE project, the following aspects need to be developed:
- New strategies for eco-engineering the biological mixed cultures processes towards stabilized and optimized conversion of complex organic waste streams.
- An improved mixotrophic strain for the continuous production of platform chemicals that can be used for further processing into fuel components.
- New robust catalysts producing selectively H2 from wet biomass under hydrothermal conditions.
- New or improved catalysts to address the integration of typically independent reactions into a one-step process for the conversion of platform chemicals into jet-fuel range hydrocarbons.
- A full process that allows elucidating the techno-economic requirements for full market integration.
During this second reporting period, significant progress has been made across multiple work packages. The most effective strategy for fermenting food waste (FW) into propionic acid was identified through the optimisation of both abiotic and biotic parameters. In parallel, efficient treatment ("polishing") of simulated fermentation effluent was successfully achieved using a Microbial Electrolysis Cell (MEC). Additionally, various eco-engineering strategies to enhance food waste conversion were investigated.
Genetic modification of the bacterium C. necator has shown excellent results, reaching outstanding carbon conversion efficiencies. Optimal fermentation conditions have also been defined for converting carboxylic acids into the platform molecules acetoin and 2,3-butanediol (2,3-BDO). The membrane biofilm reactor, developed and constructed during the first reporting period, has been operated with very promising outcomes.
Advances were also achieved in the field of catalytic processes for chemical conversion. of 2,3-BDO and acetoin. Success was demonstrated in the carbon–carbon (C–C) coupling of pure acetoin with a biomass-derived molecule, as well as in the hydrodeoxygenation (HDO) of the resulting compound. The design of multifunctional catalysts for the one-pot conversion of acetoin into jet-fuel-range hydrocarbons is currently underway. Moreover, a significant improvement in carbon yield towards non-oxygenated hydrocarbons—suitable for jet fuel formulation—was achieved using 2,3-BDO as feedstock. The effect of impurities in 2,3-BDO effluents is also being studied.
Building upon the advances from the first reporting period, a series of supported catalysts were synthesised and evaluated in a lab-scale continuous-flow reactor for hydrogen production via gasification. Comparative performance testing enabled the selection of the most promising combinations of active metals and supports.
Individual process models have been developed for the various conversion steps and have been calibrated using initial experimental data. These models form the foundation for the integrated process model, which is now under development. Together with the defined framework assumptions, this model will support the upcoming techno-economic and environmental assessments central to the project's overall evaluation.
Genetic modification of the bacterium C. necator has shown excellent results, reaching outstanding carbon conversion efficiencies. Optimal fermentation conditions have also been defined for converting carboxylic acids into the platform molecules acetoin and 2,3-butanediol (2,3-BDO). The membrane biofilm reactor, developed and constructed during the first reporting period, has been operated with very promising outcomes.
Advances were also achieved in the field of catalytic processes for chemical conversion. of 2,3-BDO and acetoin. Success was demonstrated in the carbon–carbon (C–C) coupling of pure acetoin with a biomass-derived molecule, as well as in the hydrodeoxygenation (HDO) of the resulting compound. The design of multifunctional catalysts for the one-pot conversion of acetoin into jet-fuel-range hydrocarbons is currently underway. Moreover, a significant improvement in carbon yield towards non-oxygenated hydrocarbons—suitable for jet fuel formulation—was achieved using 2,3-BDO as feedstock. The effect of impurities in 2,3-BDO effluents is also being studied.
Building upon the advances from the first reporting period, a series of supported catalysts were synthesised and evaluated in a lab-scale continuous-flow reactor for hydrogen production via gasification. Comparative performance testing enabled the selection of the most promising combinations of active metals and supports.
Individual process models have been developed for the various conversion steps and have been calibrated using initial experimental data. These models form the foundation for the integrated process model, which is now under development. Together with the defined framework assumptions, this model will support the upcoming techno-economic and environmental assessments central to the project's overall evaluation.
The synergetic coupling of biotechnological, thermochemical and catalytic routes proposed in BIOCTANE is a disruptive strategy that may result in an efficient valorization of biogenic waste, maximizing the recovery of mass and energy. The second reporting period of the project has led to notable scientific advances, laying a solid foundation for future development and impact. Key results include the optimisation of fermentation strategies for converting food waste into propionic acid, the development and testing of new genetic modifications in C. necator with high carbon efficiency, and the identification of fermentation conditions for producing acetoin and 2,3-butanediol. Additionally, microbial electrolysis has proven effective for polishing fermentation effluents, and the membrane biofilm reactor has delivered promising operational results.
Regarding the catalytic steps of the project, significant progress has been made in the synthesis and characterisation of new catalysts for the conversion of 2,3-BDO and acetoin into jet-fuel-range hydrocarbons. Key advances include successful C–C coupling reactions and hydrodeoxygenation of biomass-derived intermediates, as well as improved carbon yields to C8+ olefins from 2.3-BDO. In parallel, supported catalysts for hydrogen production via gasification were developed and tested, enabling the selection of the most promising formulations.
A full overview of the results, including performance metrics, environmental assessments, and techno-economic evaluations, will be provided in the final report.
Regarding the catalytic steps of the project, significant progress has been made in the synthesis and characterisation of new catalysts for the conversion of 2,3-BDO and acetoin into jet-fuel-range hydrocarbons. Key advances include successful C–C coupling reactions and hydrodeoxygenation of biomass-derived intermediates, as well as improved carbon yields to C8+ olefins from 2.3-BDO. In parallel, supported catalysts for hydrogen production via gasification were developed and tested, enabling the selection of the most promising formulations.
A full overview of the results, including performance metrics, environmental assessments, and techno-economic evaluations, will be provided in the final report.