Sustainable Aviation Fuel Molecules from (Hemi)Cellulose: Computational Insights into Synthesis Routes, Fuel Properties, and Process Chemistry Metrics
Date
2024-08-13
Journal Title
Journal ISSN
Volume Title
Publisher
ACS Sustainable Chemistry and Engineering
Abstract
Production of sustainable aviation fuels (SAFs) can significantly reduce the aviation industry’s carbon footprint. Current pathways that produce SAFs in significant volumes from ethanol and fatty acids can be costly, have a relatively high carbon intensity (CI), and impose sustainability challenges. There is a need for a diversified approach to reduce costs and utilize more sustainable feedstocks effectively. Here, we map out catalytic synthesis routes to convert furanics derived from the (hemi)cellulosic biomass to alkanes and cycloalkanes using automated network generation with RING and semiempirical thermochemistry calculations. We find >100 energy-dense C8–C16 alkane and cycloalkane SAF candidates over 300 synthesis routes; the top three are 2-methyl heptane, ethyl cyclohexane, and propyl cyclohexane, although these are relatively short. The shortest, least endothermic process chemistry involves C–C coupling, oxygen removal, and hydrogen addition, with dehydracyclization of the heterocyclic oxygens in the furan ring being the most endothermic step. The global warming potential due to hydrogen use and byproduct CO2 is typically 0.7–1 kg CO2/kg SAF product; the least CO2 emitting routes entail making larger molecules with fewer ketonization, hydrogenation, and hydrodeoxygenation steps. The large number of SAF candidates highlights the rich potential of furanics as a source of SAF molecules. However, the structural dissimilarity between reactants and target products precludes pathways with fewer than six synthetic steps, thus necessitating intensified processes, integrating multiple reaction steps in multifunctional catalytic reactors.
Description
This article was originally published in ACS Sustainable Chemistry and Engineering. The version of record is available at: https://doi.org/10.1021/acssuschemeng.4c04199. Copyright © 2024 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY-NC-ND 4.0 https://creativecommons.org/licenses/by-nc-nd/4.0/
Keywords
jet fuels, GWP, biomass, synthesis routes, furans, fuels
Citation
Chang, Chin-Fei, Kristin Paragian, Sunitha Sadula, Srinivas Rangarajan, and Dionisios G. Vlachos. “Sustainable Aviation Fuel Molecules from (Hemi)Cellulose: Computational Insights into Synthesis Routes, Fuel Properties, and Process Chemistry Metrics.” ACS Sustainable Chemistry & Engineering 12, no. 34 (August 26, 2024): 12927–37. https://doi.org/10.1021/acssuschemeng.4c04199.