AD-LIBIO

Investors: Energy Transition Fund (Federal Agency Belgium).

Participants: Katholieke Universiteit Leuven, Universiteit Gent, Thomas More Antwerpen, Vrije Universiteit Brussel, Instituut voor Natuur- en Bosonderzoek.

Aim: Producing advanced liquid biofuels for next-generation engine concepts enabled by innovative wood breeding and catalytic processes.

General conclusions:

· Advancements in wood breeding and feedstock valorisation: The project made significant strides in developing high cellulose feedstock through advanced breeding techniques, focusing on creating commercial poplar hybrids with high cellulose and low lignin content. Field trials demonstrated that downregulated CSE gene poplars maintain reduced lignin levels over time, resulting in up to a 67% increase in saccharification efficiency, which is critical for bioethanol production and chemical pulp yield.

·         Innovative gene editing techniques: The successful implementation of CRISPR-Cas9 for gene editing in poplar trees has shown promise for optimizing lignin content without yield penalties. The development of a transgene-free genome editing technique using Agrobacterium tumefaciens transformation is particularly notable, as it could facilitate commercialization by allowing gene-edited trees to avoid GMO classifications under future EU legislation. This has generated interest from forest biotech and pulp companies for potential applications in their elite germplasm.

·         Pilot-scale biofuel production: The project successfully demonstrated the production of second-generation biofuels on a pilot scale, achieving properties comparable to conventional gasoline. The use of inexpensive lignocellulosic waste streams positions these biofuels as competitive alternatives in the market. In addition to serving as vehicle fuel, the components of this biofuel could act as precursors for various chemicals, enhancing opportunities for commercial partnerships with industry leaders.

·         Promising results for spark ignition engines: The isomerised Ad-Libio fuel blend has shown significant potential as a sustainable replacement for gasoline in spark ignition engines, offering a direct method to reduce CO₂ emissions. Further investigation is needed to assess engine wear and compatibility, but the results so far support its feasibility as an economically viable alternative.

·         Economic and environmental insights: Analysis within the transport sector predicts a significant decline in fuel consumption, with short rotation coppice gaining renewed attention as a viable land use option, including potential applications in substituting peat in potting soil. The project's findings emphasize the importance of using low-cost, locally sourced wood for bio-naphtha production over imported biofuels, thus promoting sustainability.

·         Collaboration and future directions: The ongoing collaboration among project partners and stakeholders is crucial for translating research findings into practical applications. The project sets the stage for future research into alternative feedstocks, enhanced biofuel production methods, and expanded commercial opportunities in the bio-economy, ultimately supporting a transition to more sustainable energy solutions.

List of publications:

·         De Meester, B., et al. (2020). Tailoring poplar lignin without yield penalty by combining a null and haploinsufficient CINNAMOYL-CoA REDUCTASE2 allele. Nature Communications, https://www.nature.com/articles/s41467-020-18822-w

·         De Vries, L., et al. (2021). CRISPR-Cas9 editing of CAFFEOYL SHIKIMATE ESTERASE 1 and 2 shows their importance and partial redundancy in lignification in Populus tremula × P. alba. Plant Biotechnology Journal, https://onlinelibrary.wiley.com/doi/full/10.1111/pbi.13651

·         Van den Oever, A.E.M., et al. (2021). Life cycle environmental impacts of compressed biogas production through anaerobic digestion of manure and municipal organic waste. Journal of Clean Production, https://www.sciencedirect.com/science/article/abs/pii/S0959652621013755

·         De Meester, B., et al. (2022). Field and saccharification performances of poplars severely downregulated in CAD1. New Phytologist, https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.18366

·         De Meester, B., et al. (2022). Lignin engineering in forest trees: From gene discovery to field trials. Plant Communications, https://www.sciencedirect.com/science/article/pii/S2590346222003029

·         De Meester, B., et al. (2022). Engineering Curcumin Biosynthesis in Poplar Affects Lignification and Biomass Yield. Frontiers in Plant Science, https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.943349/full

·         Robeyn, T., et al. (2022). Investigation of naphtha-type biofuel from a novel refinery process. SAE International, https://www.sae.org/publications/technical-papers/content/2022-01-0752/

·         Robeyn, T., et al. (2022). Development of a novel drop-in naphthenic spark ignition biofuel by means of a fuel blend calculator and a simplified octane number verification method. SAE International, https://www.sae.org/publications/technical-papers/content/2023-01-0317/

·         Larsson, T., et al. (2022). Machine learning for fuel property predictions: A multi-task and transfer learning approach. SAE International, https://www.sae.org/publications/technical-papers/content/2023-01-0337/

·         Shabeik, H.., et al. (2022). Synthesis of liquid biofuels from biomass by hydrothermal gasification: A critical review. Renewable and Sustainable Energy Reviews, https://www.sciencedirect.com/science/article/abs/pii/S136403212200716X

·         Desair, J., et al. (2022). Short rotation coppice in Belgium: Review on opportunities, barriers and effects. INBO Reports, https://pureportal.inbo.be/en/publications/short-rotation-coppice-in-belgium-review-on-opportunities-barrier

·         Desair, J., et al. (2022). Rijden op korte-omloophout – kan dat wel duurzaam? INBO Newsletter, https://pureportal.inbo.be/en/publications/rijden-op-korte-omloophout-kan-dat-wel-duurzaam

·         Desair, J., et al. (2022). Korteomloophout in België uitgespit. INBO Newsletter, https://pureportal.inbo.be/en/publications/korteomloophout-in-belgi%C3%AB-uitgespit

·         Desair, J. (2022). Even wat hout tanken: een duurzaam alternatief voor fossiele brandstoffen? EOS Magazine, https://pureportal.inbo.be/en/publications/even-wat-hout-tanken-een-duurzaam-alternatief-voor-fossiele-brand

·         Hoengenaert, L., et al. (2023). Microparticle-mediated CRISPR DNA delivery for genome editing in poplar. Frontiers in Plant Science, https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1286663/full

·         Li, W., et al. (2024). Woody plant cell walls: Fundamentals and utilization. Molecular Plant, https://www.sciencedirect.com/science/article/pii/S1674205223004021

·         Boerjan, W., et al. (2024). Top five unanswered questions in plant cell surface research. Cell Surface, https://www.sciencedirect.com/science/article/pii/S2468233024000033

·         Boerjan, W., et al. (2024). Social and biological innovations are essential to deliver transformative forest biotechnologies. New Phytologist, https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19855

·         Robeyn, T., et al. (2024). A Pressure-Oscillation-Based RON Estimation Method for Spark Ignition Fuels beyond RON 100. Energies, https://www.mdpi.com/1996-1073/17/6/1362

·         Robeyn, T., et al. (2024). Alternative RON estimation method by using pressure oscillation analysis, serving novel spark ignition fuel development. Fuel, https://www.sciencedirect.com/science/article/abs/pii/S0016236124002321

·         Desair, J., et al. (2024). Waar is de houtakker gebleven. Boomblad, https://pureportal.inbo.be/en/publications/waar-is-de-houtakker-gebleven-2

·         Van den Oever, A., et al. (2025). The role of biorefineries in the future Belgian energy system: a transition life cycle assessment. Journal of Industrial Ecology, (submitted).

·         Latine, H., et al. (2025). Catalytic conversion of lignocellulose to naphtha: unlocking sustainable pathways to renewable fuel for engines and feedstock for polymers. Joule, (submitted).

·         Latine, H., et al. (2025). Techno-economic and environmental advances in converting lignocellulose to naphtha for fuels and polymers. Environmental Science & Technology, (submitted).