Compatibility of CO2 adsorbents with cement-, lime- and cement-lime based materials. Innovations in carbon capture and utilization technologies

The compatibility of three CO 2 -capturing mesoporous nanomaterials with cement-, lime- and cement-lime based materials was studied: a calcined Mg Al hydrotalcite and two mesoporous organosilica with ethylene (ethane-PMO) and phenylene (benzene-PMO) bridges. Isothermal calorimetry, thermogravimetric analysis and zeta-potential tests showed that the best compatibility results were achieved for hydrotalcite at 20 % of addition, which accelerated cement hydration by up to 100 % and increased its intensity. All hydrotalcite ratios studied improved the hydration results of the cement. Ethane-PMO produced a delay in cement hydration and it was found that for low percentages of addition (up to 1 %) the results were similar to those of the cement. Both the hydrotalcite at a high addition level and the ethane-PMO at a low addition level are compatible materials that support proper hydration and the formation of C-S-H phases in cement. Once proven to be compatible with cementitious and lime matrices, the incorporation of these CO 2 -capturing nanomaterials into cement- and lime-based materials could reduce their carbon footprint, making them more environmentally friendly. • Calcined hydrotalcite accelerated cement hydration and intensified it. • Benzene-PMO led to an almost total hindrance of hydration and setting of the cement • Ethane-PMO showed a behavior that could be assumed in practical terms. • Calcined hydrotalcite and ethane-PMO are compatible with cement-based materials. • Calcined hydrotalcite and ethane-PMO could reduce carbon footprint of cement-based materials.