Influence of silica types on synthesis and performance of amine-silica hybrid materials used for CO2 capture

Amine-silica hybrid materials have been investigated extensively in terms of their suitability for postcombustion CO₂ capture. However, research on how the silica types affects the synthesis and performance of amine-silica hybrid materials is scarce. In this study, four types of commonly used and representative silica including precipitated silica, fumed silica, MCM-41, and silica gel are used to synthesize a series of comparable materials by grafting a silane onto them. We undertake a porosity analysis of plain silica and the amine-silica hybrid materials and determined the CO₂ adsorption performance of amine-silica hybrid materials. The results suggest that precipitated silica is a superior and promising support material for amine-silica hybrid materials synthesis by grafting. The amine-silica hybrid material supporting with precipitated silica possesses relatively high amine content, exhibits good porosity, and obtains the highest CO₂ adsorption capacity and amine efficiency compared to those of three other amine-silica hybrid materials.