Development of Alkali Nitrate‐Containing Li₄SiO₄ for High‐Temperature CO₂ Capture

Abstract

Abstract High efficiency alkali nitrate‐containing Li 4 SiO 4 sorbents were synthesized by a hydration technique to improve their sorption performances at low CO 2 concentrations. X‐ray diffraction (XRD), scanning electron microscopy (SEM), X‐ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC), and thermogravimetric analyses were used to detect the characteristics of the samples. The results showed that the presence of KNO 3 and NaNO 3 induced small crystallite size, corrugated morphologies and the formation of eutectic phases, noticeably facilitating sorption processes. At the optimized additive amount of 0.035 mol %, NaNO 3 ‐containing Li 4 SiO 4 reached a maximum absorption capacity (≈34.6 wt %). Moreover, both alkali nitrate‐containing Li 4 SiO 4 sorbents showed good cyclic properties, demonstrating their great potential for high‐temperature CO 2 capture.