三维蠕虫状介孔二氧化硅对CO_2吸附性能的研究

CO_2 Adsorption on Mesoporous Silica with 3-D Wormhole Structure

研究了有机胺固载3D蠕虫状介孔二氧化硅MSU-J的表面结构、介孔类型、氮含量以及吸附温度对CO2吸附性能的影响,并采用傅里叶红外光谱、透射电镜、N2吸附/脱附、热重分析和元素分析等方法研究了介孔结构和CO2吸附性能。结果表明,采用浸渍法对MSU-J进行氨基改性的效率明显高于接枝法,产物具有较高的CO2吸附量,且水化处理后介孔MSU-J表面的Si-OH得以再生使氨基的负载量增加,CO2吸附量从43.2mg/g增加到52.6mg/g。与SBA-15相比,氨基改性后MSU-J的CO2吸附量从28.4 mg/g增加到154.5 mg/g,远大于前者的23.4-65.4mg/g。吸附温度对MSU-J吸附CO2的影响很大,且随吸附温度降低,吸附量升高,在室温时达最大值125mg/g,故MSU-J的低温吸附性能优异。

CO2 adsorption performance of organic amine immobilized 3-D wormhole structured mesoporous silica MSU-J was studied, focusing on its surface structure, types of mesopores, amino content and adsorption conditions （adsorption temperature and adsorption pressure）. The mesoporous structure and CO2 adsorption capacity of MSU-J were explored by Fourier transform infrared spectroscopy, transmission electron microscopy, N2 adsorption/desorption, thermogravimetric analysis and elemental analysis. The results indicated that the efficiency of MSU-J modified by amine impregnation was significantly higher than by grafting. The regeneration of Si-OH condensed in the process of calcination by hydrolytic treatment successfully contributed to the increase of amino loading and the CO2 adsorption capacity increased from 43. 2 mg/g to 52. 6 mg/g. Compared with SBA-15, CO2 adsorption capacity of amino modified MSU-J increased from 28. 4 mg/g to 154. 5 mg/g which was far larger than that of SBA-15（23. 4-65.4 mg/g）. Adsorption temperature on the MSU-J had great influence on the adsorption of CO2. The CO2 adsorption capacity increased with the decrease of adsorption temperature and achieved the peak value of 125 mg/g at room temperature.