Silica Supported MgO as An Adsorbent for Precombustion CO2 Capture

Abstract

MgO-silica nanocomposites were synthesized by dispersing MgO on three different silica supports, viz., ordered mesoporous MCM-41, SBA-15, and the nonporous fibrous silica nanospheres material (KCC-1; KAUST Catalysis Center-1) using a simple wet impregnation-calcination procedure. The materials were evaluated for intermediate-temperature CO2 adsorption (200 °C) applicable to precombustion CO2 capture in integrated gasification combined cycle (IGCC). The results indicate that both CO2 adsorption capacity and kinetics are substantially improved upon dispersion of MgO on silica supports compared with single component MgO. The morphology of the silica regulates the\xa0degree of improvement in CO2 adsorption capacity. Nanoflower silica KCC-1 supported MgO, studied for CO2 capture for the first time, shows an approximately 1700% higher CO2 capacity than pristine MgO and 80–110% higher than MgO supported by the other conventional ordered mesoporous silica, that is, MCM-41 or SBA-15. The outstanding adsorption perfor...