In an effort to decarbonize the global economy by 50% in 2030 and achieve net-zero carbon emissions by 2050, there is a dire need to electrify industrial processes [1]. Approximately 8% of global carbon emissions comes from cement production [2]. Considering the rising demand for cement due to infrastructure expansion, it is critical to develop new concepts for the decarbonization of cement production. With this goal in mind, our work explores the effectiveness of flow-assisted cement electrolysis as a replacement to conventional fossil fuel based high-temperature kilns in cement manufacturing plants [3].In this study, we employ a scalable 3-channel flow-reactor with acidic anolyte, basic catholyte, and a neutral chemical flush in between to generate calcium hydroxide, Ca(OH)2 [4, 5], which is the key ingredient in cement manufacturing. The central channel is separated from either half cells by a cation exchange and an anion exchange membrane. The electrochemical performance of the proposed cement electrolyzer under a variety of operating conditions is investigated by considering the key variables in reactor design, including flow rate, temperature, catalyst choice and feed concentrations, to shed light into the practical challenges of running a 3-channel flow reactor. Our preliminary study indicates that membranes are possibly responsible for a significant fraction of the limited yields of Ca(OH)2. Specifically, the anion exchange membranes tested are susceptible to degradation in alkaline conditions displaying poor ionic conductance, whereas the cation exchange membranes allow significant water crossover. The findings from this study pave the way in understanding key components for cement electrolysis and other electrochemical systems employing 3-channel flow reactors. References DeAngelo, J., et al., Energy systems in scenarios at net-zero CO2 emissions. Nature Communications, 2021. 12(1): p. 6096. Ellis, L.D., et al., Toward electrochemical synthesis of cement—An electrolyzer-based process for decarbonating CaCO3 while producing useful gas streams. PNAS, 2019. 117(23): p.12584. Rissman, J., et al., Technologies and policies to decarbonize global industry: Review and assessment of mitigation drivers through 2070. Applied Energy, 2020. 266: p. 114848. Perego, A., et al., Electrochemical Flow Reactor for Cement Clinker Production. ECS Meeting s, 2021. MA2021-02(27): p. 840. Olsson, J.A., S.A. Miller, and M.G. Alexander, Near-term pathways for decarbonizing global concrete production.Nature Communications, 2023. 14(1): p. 4574.
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