MgO/Al_2O_3吸附剂对CO_2静态吸附性能研究

CO_2 capture using MgO/Al_2O_3 materials as adsorbent

采用等体积浸渍法制备MgO/Al2O3吸附剂。利用X光电子衍射(XRD)、氮气吸附、原位红外吸附等手段对材料的结构进行表征,通过静态吸附的方法对其吸附性能进行了测定。实验结果表明,所得到的MgO/Al2O3吸附剂,主要存在3个不同的碱性位,CO2吸附后主要是以碳酸氢盐、双齿碳酸盐和单齿碳酸盐的形式存在的。当MgO的负载量为10wt%时,其对CO2的吸附量是最大的。在30℃条件下,其对CO2的吸附量为54.1mg/g,随着温度的升高,吸附量有所降低,在100℃时,其对CO2的吸附量为31mg/g,吸附量的降低主要是由于碳酸盐的分解所致。

MgO/Al2O3 adsorbent was prepared by impregnation method. The structure and surface properties of the material were characterized by XRD, N2 adsorption-desorption and Fourier transform infrared（FTIR） spectra. The results showed that this adsorbent had three basic sites,which can reacted with CO2 to form bicarbonate, bidentate carbonate and monodentate carbonate. Their CO2 uptakes could be significantly improved when the MgO loading was increased from 0 to 10 wt%. The adsorption capacity for CO2 was 54.1 mg/g at 30℃. The CO2 uptake was decreased due to the decomposition of carbonate species with the temperature increasing.