Novel comprehensive life cycle assessment (LCA) of sustainable flue gas carbon capture and utilization (CCU) for surfactant and fuel via Fischer-Tropsch synthesis

Sadhukhan, Jhuma; Fisher, Oliver J.; Cummings, Benjamin; Xuan, Jin

Abstract

This novel study presents an effective comprehensive life cycle assessment (LCA) of a novel sustainable carbon dioxide capture and utilization (CCU) system to co-produce alcohol ethoxylate (AE7), a valuable surfactant (a high-value chemical component of liquid detergents), and low-medium distillate range liquid fuel. Conventionally, AE7 is produced by reacting fatty alcohols with ethylene oxide from mostly fossil and marginally bio-based resources. This research develops novel AE7 production using carbon sources from flue gas of paper and steel industries, addressing a critical gap in the literature. The core process is Fischer-Tropsch (FT) synthesis using syngas formed by the reverse-water-gas-shift reaction, where recycled CO2 reacts with H2. FT produces C11-C13 alkanes and a light-to-medium fuel co-product. The alkanes are converted into C12-C14 fatty alcohols through dehydrogenation, hydroformylation, and hydrogenation. Fatty alcohols react with ethylene oxide to form AE7. The yields (w/w) of AE7 and the fuel co-products are 3.7 % and 3.4 % for paper industry flue gas, and 8.0 % and 9.5 % for steel industry flue gas, respectively. Renewable (wind) electricity meets the hydrogen demand and electricity needs for the reactions, a total of 13.4 and 33.3 kWh/kg flue gas, respectively. The life cycle impact assessment includes global warming potential (GWP) and other impacts using ReCiPe, Impact+, and Product Environmental Footprint methods. Baseline scenarios show GWP ranging from 2.2 to 3.6 kg CO2e/kg surfactant for conventional cradle-to-gate AE production systems. The new systems have GWP ranging 0.4–1.3 kg CO2e/kg flue gas (cradle-to-gate) using mass allocation. Meanwhile, the paper industry's flue gas system has biogenic CO2, while the steel industry's CO2 is fossil-based. Considering the GWP reductions due to biogenic CO2 contents, their overall GWP is 2.56 kg CO2e and 10.33 kg CO2e per kg of product (AE7 +fuel) (cradle-to-grave) using economic allocation. Thus, biogenic CCU is critical for the sustainable co-production of high-value surfactants and fuel.

Citation

Sadhukhan, J., Fisher, O. J., Cummings, B., & Xuan, J. (2025). Novel comprehensive life cycle assessment (LCA) of sustainable flue gas carbon capture and utilization (CCU) for surfactant and fuel via Fischer-Tropsch synthesis. Journal of Co2 Utilization, 92, Article 103013. https://doi.org/10.1016/j.jcou.2024.103013

• Journal Article Type: Article
• Acceptance Date: Dec 27, 2024
• Online Publication Date: Jan 9, 2025
• Publication Date: 2025-02
• Deposit Date: Jan 21, 2025
• Publicly Available Date: Jan 24, 2025
• Journal: Journal of CO2 Utilization
• Electronic ISSN: 2212-9820
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 92
• Article Number: 103013
• DOI: https://doi.org/10.1016/j.jcou.2024.103013
• Keywords: CCUS, CCU, CDU, Carbon dioxide utilization, LCA, Circular carbon economy, Surfactant, High-value product, Product environmental footprint
• Public URL: https://nottingham-repository.worktribe.com/output/44423148
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S2212982024003482?via%3Dihub
• Additional Information: This article is maintained by: Elsevier; Article Title: Novel comprehensive life cycle assessment (LCA) of sustainable flue gas carbon capture and utilization (CCU) for surfactant and fuel via Fischer-Tropsch synthesis; Journal Title: Journal of CO2 Utilization; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.jcou.2024.103013; Content Type: article; Copyright: © 2025 The Author(s). Published by Elsevier Ltd.