Aminosilica adsorbents for post-combustion CO₂ capture: Effect of steam and oxygen on long-term stability

Aminosilica materials are promising candidates for post-combustion CO₂ capture. However, their stability under realistic flue gas conditions and economically viable regeneration conditions is not yet well understood. Using low pressure steam available readily in a power plant is a commercially attractive regeneration option. To evaluate the feasibility of this option, stability testing of adsorbents in the presence of steam must be carried out. Also, power plant flue gas exhaust typically contains 5-10% oxygen. The degradation of aminosilica materials under oxidative conditions, however, has not been explored in much detail. In this report we investigate the stability of a variety of amine functionalized silica materials in the presence of steam and oxygen. It was found that steam had an adverse effect on all the materials used in the tests whereas oxygen degraded some adsorbents significantly while others were unaffected by it under the experimental conditions used in this study.