(357f) Integrating CO2 Electrolyzers in Electrochemical Plants: Heat Integration, Techno-Economic Analysis, and Life Cycle Assessment of the Production of 1-Butene from CO2

Efforts to mitigate climate change have increased interest in utilizing CO₂ as a sustainable feedstock within the chemical industry [1]. Recent progress in electrochemical CO₂ reduction, facilitated using renewable electricity sources, presents a promising avenue for synthesizing valuable C₂₊ chemicals [2]. While the initial focus has been on the development of electrolyzers, recent research has broadened to include process design and downstream separation techniques [3]. However, the question remains how to integrate feedback from process design back into electrolyzer development.

This work introduces a feedback loop from process design to electrolyzer development. The loop combines process modeling, heat integration, techno-economic analysis, and life cycle assessment.

The resulting workflow is demonstrated for the CO₂ electroreduction to ethylene and subsequent dimerization to 1-butene [4]. From the analysis, we derive development targets for CO₂ electrolyzers. We assess the significance of cell voltage and Faradaic efficiency, highlighting that single-pass conversion minimally impacts overall process feasibility. Moreover, we emphasize the benefits of integrating electrolyzers with downstream and upstream units.

In summary, we combine electrolyzer development and process systems engineering perspectives by bridging the scales from electrolyzers to integrated processes with economic and sustainability objectives. This study illustrates the integration of a process-oriented approach into technology advancement for an electrified chemical industry.

Acknowledgments

This publication was created as part of NCCR Catalysis (grant number 180544), a National Centre of Competence in Research funded by the Swiss National Science Foundation.

References

[1] W. Chung, W. Jeong, J. Lee, J. Kim, K. Roh, and J. H. Lee, “Electrification of CO2 conversion into chemicals and fuels: Gaps and opportunities in process systems engineering”, Comput. Chem. Eng., 170 (2023), 108106.

[2] S. Lee, D. Kim, and J. Lee, “Electrocatalytic Production of C3‐C4 Compounds by Conversion of CO2 on a Chloride‐Induced Bi‐Phasic Cu2O‐Cu Catalyst”, Angewandte Chemie, 127 (2015), 14914–14918.

[3] A. Somoza-Tornos, O. J. Guerra, A. M. Crow, W. A. Smith, and B.-M. Hodge, “Process modeling, techno-economic assessment, and life cycle assessment of the electrochemical reduction of CO2: a review”, iScience, 24 (2021), 102813.

[4] M. G. Lee, X.-Y. Li, A. Ozden, J. Wicks, P. Ou, Y. Li, R. Dorakhan, J. Lee, H. K. Park, J. W. Yang, B. Chen, J. Abed, R. dos Reis, G. Lee, J. E. Huang, T. Peng, Y.-H. Chin, D. Sinton, and E. H. Sargent, “Selective synthesis of butane from carbon monoxide using cascade electrolysis and thermocatalysis at ambient conditions”, Nat. Catal., 6 (2023), 310–318.