Structural changes of silica mesocellular foam supported amine-functionalized CO ₂ adsorbents upon exposure to steam

Three classes of amine-functionalized mesocellular foam (MCF) materials are prepared and evaluated as CO ₂ adsorbents. The stability of the adsorbents under steam/air and steam/nitrogen conditions is investigated using a Parr autoclave reactor to simulate, in an accelerated manner, the exposure that such adsorbents will see under steam stripping regeneration conditions at various temperatures. The CO ₂ capacity and organic content of all adsorbents decrease after steam treatment under both steam/air and steam/nitrogen conditions, primarily due to structural collapse of the MCF framework, but with additional contributions likely associated with amine degradation during treatment under harsh conditions. Treatment with steam/air is found to have stronger effect on the CO ₂ capacity of the adsorbents compared to steam/nitrogen.