An efficient method for extracting the dissolved CO₂ in the oceans would effectively enable the separation of CO₂ from the atmosphere without the need to process large volumes of air, and could provide a key step in the synthesis of renewable, carbon-neutral liquid fuels. While the extraction of CO₂ from seawater has been previously demonstrated, many challenges remain, including slow extraction rates and poor CO₂ selectivity, among others. Here we describe a novel solution to these challenges – efficient CO₂ extraction from seawater using bipolar membrane electrodialysis (BPMED). We characterize the performance of a custom designed and built CO₂-from-seawater prototype, demonstrating the ability to extract 59% of the total dissolved inorganic carbon from seawater as CO₂ gas with an electrochemical energy consumption of 242 kJ mol⁻¹(CO₂).

The current enthusiasm for the circular economy (CE) offers a unique opportunity to advance the impact of research on sustainability transitions. Diverse interpretations of CE by scholars, however, produce partly opposing assessments of its potential benefits, which can hinder progress. Here, we synthesize policy‐relevant lessons and research directions for a sustainable CE and identify three narratives—optimist, reformist, and skeptical—that underpin the ambiguity in CE assessments. Based on 54 key CE scholars’ insights, we identify three research needs: the articulation and discussion of ontologically distinct CE narratives; bridging of technical, managerial, socio‐economic, environmental, and political CE perspectives; and critical assessment of opportunities and limits of CE science–policy interactions. Our findings offer practical guidance for scholars to engage reflexively with the rapid expansion of CE knowledge, identify and pursue high‐impact research directions, and communicate more effectively with practitioners and policymakers.