Comparison of the kinetic of carbon dioxide adsorption in materials containing calcium, zirconium, and tin

The urgent need to mitigate climate change impacts and achieve net zero emissions has led to extensive research on carbon dioxide (CO₂)-capture technologies. This study focuses on the kinetics of CO₂ capture using solid adsorbents specifically through thermal gravimetric analysis (TGA). The research explores the principles behind TGA and its application in analyzing adsorbent performance and the significance of kinetics in optimizing CO₂-capture processes. Solid adsorbents have gained significant attention due to their potential for efficient and cost-effective CO₂ capture. Therefore, three different types of adsorbents, namely calcium-, tin-, and zirconium-based ones (quicklime: CaO, potassium stannate: K₂SnO₃, and sodium zirconate: Na₂ZrO₃), in adsorbing high-temperature carbon dioxide were investigated; their quality and performance by various factors such as price, stability, non-toxicity, and efficiency are different. The diffusion models and geometrical contraction models were the best-fitted models to explain the kinetic of these solid adsorbents for high-temperature CO₂ sorption; it means the morphology is important for solid adsorbent performance. The minimum energy needed to start a reaction for K₂SnO₃, Na₂ZrO₃, and CaO, is 73.55, 84.33, and 86.23 kJ·mol⁻¹, respectively; with the lowest value being for potassium stannate. The high-temperature CO₂ adsorption performance of various solid adsorbents in regard with the rate of reaction followed the order of K₂SnO₃ > CaO >> Na₂ZrO₃, based on experiments and kinetic studies.