A novel aerogel sodium-based sorbent for low temperature CO2 capture

Abstract

The object of this research is to develop a novel sodium-based solid sorbent with amine modification for low temperature CO2 capture in coal-fired power plants. The new sorbent (NaN) was synthesized with Na2CO3, 3-aminopropyltriethoxysilane (APTES) and tetraethylorthosilicate (TEOS) through sol-gel method, and then dried with three different methods: conventional drying (CD), organic solvent sublimation drying (OSSD), and supercritical fluid drying (SCFD). The CO2 sorption capacity of NaN was evaluated using a fixed-bed reactor under various conditions including the temperature and moisture concentration of the flue gas. Results demonstrated that the optimized SCFD-NaN with APTES:Na2CO3:TEOS mole ratio of 1:1:1 reached the highest CO2 sorption capacity of 2.51 mmol/g under the best experimental conditions (50°C, H2O/CO2 = 1:1). Moreover, the NaN sorbent was regenerable and stable during the 10 cyclic operations. Thus, the SCFD-NaN sorbent is a promising composite sorbent for CO2 capture. © 2015 Society of Chemical Industry and John Wiley & Sons, Ltd.