Preparation and application of magnesium-based CO₂ sorbent for temperature swing absorption I.Na/Mg mol ratio

A series of magnesium-based CO₂ absorbents with different Na/Mg molar ratios were prepared by precipitation method with Mg(NO₃)₂ and Na₂CO₃ as raw materials, and characterized by various methods (including XRD, SEM-EDS and DTG) to study the compositions, morphology and decomposition temperature and so on. The CO₂ absorption performance was evaluated by temperature swing absorption-desorption dynamic cyclic tests to check the impact of Na/Mg molar ratio. It can be seen that optimum molecular ratio of Na to Mg is 8.15, and the sorbents is homogeneous with lower decomposition temperature caused by small particles of the sample, and initial CO₂ adsorption capacity can reach 9.584%. Good recycling capability can be obtained as well. Compared with the initial absorption capacity, there was only 4.2% decrease after 20 recycles.