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TY - THES AU - Hellmuth, Maximilian Alexander TI - Oxidation and aromatics chemistry of novel bio-hybrid fuels PB - Rheinisch-Westfälische Technische Hochschule Aachen VL - Dissertation CY - Aachen M1 - RWTH-2025-07456 SP - 1 Online-Ressource : Illustrationen PY - 2024 N1 - Veröffentlicht auf dem Publikationsserver der RWTH Aachen University 2025 N1 - Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2024 AB - Alternative fuels offer a promising solution to defossilize the transport sector. They capitalize on their compatibility with the current infrastructure and end-use equipment, potentially reducing adaptation costs and emissions of the existing vehicle fleet. Bio-hybrid fuels combine bio-based feedstocks and carbon dioxide as carbon sources with renewable electricity, either through electrochemical conversion or through the use of green hydrogen, to meet the growing demand for sustainable liquid energy carriers. This work explores 1,3-dioxolane and 1,3-dioxane, two potential bio-hybrid fuels, on a fundamental level regarding their oxidation chemistry and impact on the formation of mono- and polycyclic hydrocarbons and soot to establish a basis for their utilization in future engine applications. The endeavor requires detailed kinetic models to analyze the underlying mechanisms, and speciation data are valuable for validating these models. Therefore, a gas chromatograph (GC) was modified to identify and quantify aromatics up to pyrene (C16). An innovative storage system complemented the GC, reducing measurement effort through method automation and enabling mobile sample collection and storage at a counterflow burner. Implementing a sampling system based on an established approach in the literature facilitated species measurements in these flames. The operating conditions of the counterflow burner were controlled to allow for a meaningful kinetic comparison between the investigated flames. A detailed comparison of the two bio-hybrid fuels revealed that the difference in carbon-oxygen bond dissociation energies significantly affects their decomposition pathways, resulting in distinct impacts on aromatics and soot formation. 1,3-Dioxolane addition to ethylene-based counterflow diffusion flames showed a synergistic effect on the formation of these pollutants (in contrast to 1,3-dioxane), which was linked to increased methyl radical abundance, enhancing propargyl radical formation. Another part of this work focused on the dominant formation pathways of naphthalene observed in the studies on the two bio-hybrid fuels. A comprehensive comparison of the experimental and kinetic model results for two flames fueled by pure allene and an allene/1-buten-3-yne mixture, followed by detailed pathway analyses, documented the dependency of naphthalene formation on C3 and C4 species. Model shortcomings in specific reactions, particularly for the C4 chemistry, were highlighted to encourage future studies to reduce their uncertainties. LB - PUB:(DE-HGF)11 DO - DOI:10.18154/RWTH-2025-07456 UR - https://publications.rwth-aachen.de/record/1017636 ER -