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

Abstract

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.