Electrochemical Synthesis of Calcium Hydroxide for Low-Carbon Cement Production: A Mini Review

The cement industry is responsible for approximately 8% of global anthropogenic CO₂ emissions, largely due to the high-temperature calcination of limestone during clinker production. Electrochemical synthesis of calcium hydroxide (Ca(OH)₂) has recently emerged as a promising low-carbon alternative that enables limestone decarbonation under near-ambient conditions. This mini review summarizes most recent progress in electrochemical Ca(OH)₂ production for low-carbon cement manufacturing. We first outline the foundational electrochemical principles enabling pH-gradient-driven CaCO₃ dissolution and Ca(OH)₂ precipitation. We then review major technological advances in reactor architecture, electrode and reaction engineering, membrane design, and feedstock diversification, highlighting strategies that significantly reduce cell voltage, mitigate membrane fouling, and enable continuous operation. Representative electrochemical systems and process configurations are systematically compared. Key technical barriers, including Ca(OH)₂ production efficiency, membrane stability, energy consumption, and feedstock impurity tolerance, are also analyzed, together with future research priorities such as advanced membrane materials, integrated process design, and AI-assisted optimization. Continued innovation in electrochemical reactor engineering and system integration could enable scalable low-carbon cement production and contribute significantly to industrial decarbonization.