Novel Li4SiO4-based sorbents from diatomite for high temperature CO2 capture

Using inexpensive porous diatomite as silicon source, novel Li₄SiO₄-based sorbents for high temperature CO₂ capture were prepared through the solid-state reaction method at lower temperature (700 °C). Effect of different raw material ratios on CO₂ absorption capacity was investigated. The results showed that CO₂ absorption capacity was dependent on the raw material ratio. When the raw material ratio was 2.6:1, the CO₂ absorption capacity reached 30.32 wt% (83% of the theoretical absorption capacity) in the atmosphere (50 mL/min N₂ and 50 mL/min CO₂). Meanwhile, it was found that the as-prepared Li₄SiO₄-based sorbents from diatomite exhibited good absorption–desorption performance.