Life cycle assessment of hexanoic acid production via microbial electrosynthesis and renewable electricity: Future opportunities

• Published in: Journal of environmental chemical engineering Vol. 12; no. 5; p. 113924
• Main Authors: Luo, Jisiwei, Pérez-Fortes, Mar, Straathof, Adrie J.J., Ramirez, Andrea
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.10.2024
• Subjects: CO2 utilisation; Flexibility; Power-to-chemicals; Sustainable aviation fuels; Power-to-chemicals; Flexibility; CO2 utilisation; Sustainable aviation fuels
• ISSN: 2213-3437
• DOI: 10.1016/j.jece.2024.113924

Microbial electrosynthesis (MES) is a novel carbon utilisation technology aiming to contribute to a circular economy by converting CO2 and renewable electricity into value-added chemicals. This study presents a cradle-to-gate life cycle assessment (LCA) of hexanoic acid (C6A) production using MES, comparing this production with alternative technologies. It also includes a cradle-to-grave LCA for potentially converting C6A into a neat sustainable aviation fuel (SAF). On a cradle-to-gate basis, MES-based C6A exhibits a carbon footprint at 5.5 t CO2eq/tC6A, similar to fermentation- and plant-based C6A. However, its direct land use is more than one order of magnitude lower than plant-based C6A. On a cradle-to-grave basis, MES-based neat SAF emits 325 g CO2eq/MJ neat SAF, which is significantly higher than the counterparts from currently certified routes and conventional petroleum-derived jet fuel. However, its negligible indirect land use change emissions might potentially make it competitive against neat SAFs originating from first-generation biomass. [Display omitted] •MES-based hexanoic acid is at the same emission level as its market competitor.•MES-based hexanoic acid uses less land than its market competitor.•Converting MES-based hexanoic acid into neat SAF is not emission-wise competitive.