(389l) A Novel KMgAl Sorbent for CO2 Capture in a Fluidized Bed

Carbon capture and storage (CCS) is recognized as a promising option for CO₂ emission reduction. The post-combustion process is more suitable for CO₂ capture for the traditional pulverized coal power plants. However, the considerable cost of CO₂ capture approximately accounts 70% of the total cost of CCS. Thus, the key technology of CO₂ capture is to reduce the parasitic energy cost of the system. CO₂ chemical adsorption using dry regenerable solid sorbents had attracted much attention due to the low cost of raw materials and non-corrosion property. In previous study, we had found that MgO/Al₂O₃sorbent with 10wt% MgO loading showed a better performance for CO₂ capturing at low temperature in the fixed-bed. Nevertheless, the absorption amount of CO₂ was not high. Furthermore, in the absorption process, heat control is important to avoid hot spots generated during the highly exothermic carbonation reaction. Thus, a novel solid sorbent impregnated with K₂CO₃ over MgO/Al₂O₃ support was prepared and the performance for CO₂ capture was investigated in the fluidized bed. The resultshowed that the KMgAlI3010 sorbent had a high CO₂ uptake of 109.6 mg CO₂/g sorbent at the flow rate of 12 Nm³/h at 60 ^oC under simulated flue gas conditions, which was larger than those of most K-based sorbents reported before at low temperatures, and the MgO played an important role in the high CO₂ capture capacity of KMgAl sorbents,for the forming of thehydrotalcite-like compounds on the surface and in the pore of Al₂O₃after water vapor pretreatment.