Abstract
In recent years, electrocatalytic systems powered by renewable energy have gained prominence in regard to sustainable chemical production. A majority of published literature focuses on catalyst development in alkaline electrolytes, driven by advantages such as high ionic conductivity, low charge transfer resistance and rapid kinetics. Here we shed light on challenges arising from the use of alkaline electrolytes for product separation and electrolyte recovery. Delving into acid–base reaction chemistry, we identify the problematic synthesis of organic acids whereby the high-pH environment leads to dissociation or deprotonation, forming conjugate bases and water. Our analysis of an alkaline electrochemical process for glycerol oxidation highlights the significant economic hurdles, with >60% of capital costs, 70% of raw material (for example, potassium hydroside) costs and 64% of total energy costs attributed to downstream product separation. These challenges, related to acid–base reaction chemistry, are often overlooked at the catalyst development stage, resulting in a significant waste of research resources.
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Data availability
Data that support the findings of this study are provided with the manuscript and its Supplementary Information file. All data used in this study are available from the corresponding author on reasonable request.
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Acknowledgements
M.A.K. acknowledges funds received through Office of the Dean, Faculty of Engineering, University of Alberta in assistance with research-related expenditures. S.K.N. thanks Alberta Innovates and the Government of Alberta for their support through graduate scholarships.
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S.K.N. and M.A.K. conducted formal economic analysis. M.A.M.R. performed the literature review. S.K.N. and M.A.M.R. summarized the data and cowrote the first draft of the manuscript. K.K. helped with manuscript writing. S.K.N. and K.K. further revised the manuscript. M.R. and H.S.S. helped with literature review and manuscript editing. M.G.K. and M.A.K. reviewed and further edited the manuscript. M.A.K. conceptualized the work. M.G.K. and M.A.K. supervised all aspects of the work.
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Nabil, S.K., Muzibur Raghuman, M.A., Kannimuthu, K. et al. Acid–base chemistry and the economic implication of electrocatalytic carboxylate production in alkaline electrolytes. Nat Catal 7, 330–337 (2024). https://doi.org/10.1038/s41929-024-01107-6
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DOI: https://doi.org/10.1038/s41929-024-01107-6