Solution combustion synthesis derived Li₄SiO₄ for post-combustion carbon capture

Lithium-based sorbents are considered as promising candidates for post-combustion carbon capture because of their superior stability compared to CaO. In the present study, Li₄SiO₄ powders were synthesized by Solution Combustion Synthesis (SCS) technique using LiNO₃ as lithium source, TEOS as silicon source and citric acid as the fuel. CO₂ sorption tests were carried out for the synthesized samples and, powder prepared at 650°C during 4 h, which has 17 µm of particle size, 5.2 m² g⁻¹ of specific surface area, 85.2% Li₄SiO₄ phase purity with 97 nm of crystallite size showed a sorption performance as 29.5 wt% CO₂ uptake value, in thermobalance test under 92 vol% CO₂ (N₂ balance) gas concentration at 600°C. The sample had a CO₂ uptake value of 21.4 wt% under 20 vol% CO₂ concentration which was chosen to simulate industrial off-gas conditions. Also, the same sample showed a good cyclic durability during the sorption/desorption tests. The sample maintained its cyclic CO₂ uptake capability range between 21 and 24 wt% for 15 cycles.