(40p) Mesoporous MgO for Carbon Dioxide Capture at an Ambient Condition and the Effect of Calcination Steps to Sorption Performances

To cope with the climate change caused by the emission of CO₂ gas, much research has been done to develop high performance materials for CO₂ capture. In the study, mesoporous MgO sorbents were synthesized by using an aerogel method for CO₂ sorption at ambient temperatures. At the last step of the synthesis, a calcination method was developed: 1-step calcined MgO and 4-step calcined MgO. The effect of the calcination condition and method on CO₂ sorption capacity was evaluated.

The sorption capacity of as-synthesized MgO samples at 30-350°C was measured and CO₂ sorption/desorption cyclic test was carried out by using Thermogravimetric analysis(TGA). The 4-step calcined MgO has the sorption capacity of 10.6wt% and 70% of saturation was reached within 5 minutes. On the other hand, the 1-step calcined MgO showed better stability than the 4-step one in the cyclic test. Visual images and crystalline data of sorbents were confirmed by SEM, TEM and XRD. In addition, textual properties (surface area, pore size and pore volumes) of the sorbents before and after the cyclic test were compared by measuring the N₂ isotherm analysis. It was confirmed that the CO₂ sorption capacity depended on the textual properties controlled by the calcination method.