CO₂ capture using mesocellular siliceous foam (MCF)-supported CaO

CaO is a promising material as an alternative CO₂ capture material which can be used at high temperature. However, CaO sinters to form large particles under long-term high temperature conditions, resulting in a rapid decrease of its surface area and the capacity of CO₂ capture. Incorporating CaO into inert materials is a promising strategy to enhance the performance of CO₂ capture. This work investigated a novel composite material called mesocellular siliceous foam (MCF)-supported CaO to enhance the stability and capacity of CaO-based materials for CO₂ capture. The crystal structure, surface morphology and porosity property of the developed composite materials were investigated. Thermogravimetric measurements were carried out to study the cyclic CO₂ capture performance of the MCF-supported CaO composites. The results showed that a part of CaO reacted with the silica wall, and the formation of Ca₂SiO₄ within the MCF framework limited the presence of CaO in the mesopores, thus inhibited the sintering of CaO. The sample of MCF-3CaO exhibited a better performance of CO₂ capture and long-term stability, compared with the materials prepared with lower CaO loading. This work contributes to the development of high temperature CO₂ capture adsorbents, which can be applied for decarbonizing major industrials e.g. power plant.