Electrified Cement Production via Anion-Mediated Electrochemical Calcium Extraction

Cement production is a carbon-intensive industrial process, with the sector contributing ∼8% of global anthropogenic CO 2 emissions. On average, producing each kilogram of cement leads to the emission of 1 kg of CO 2 ─the combination of fuel combustion emissions and carbon released from the feedstock, limestone (CaCO 3 ). Here we report electrochemical cement production based on anion-mediated electrochemical calcium extraction (ECE) that addresses both feedstock and energy emissions. The in situ -generated acidic electrolytes release the feedstock CO 2 emissions at high purity, enabling direct carbon utilization or sequestration without costly capture and purification steps. Energy embodied within a separate H 2 output stream is sufficient to sinter Ca(OH) 2 to produce portland cement, thus removing the CO 2 emissions associated with fuel combustion. We then replace CaCO 3 with a carbon-free calcium feedstock, gypsum, thereby removing the CO 2 emissions embodied in the feedstock. Technoeconomic analysis forecasts that this method could provide a viable, decarbonized cement alternative.