以三嵌段共聚物P123(EO20—PO70-EO20)为模板剂合成了介孔泡沫氧化硅(MCF)材料.MCF经过五乙烯六胺(PEHA)修饰后用于捕捉CO2.采用扫描电镜(SEM)、透射电镜(TEM)、N2吸附-脱附、傅里叶变换红外(FTIR)光谱、热重分析(TGA)对MCF和MCF—PEHA进行了表征.结果表明,PEHA对MCF改性后,并没有破坏MCF载体本身的结构.MCF-PEHA的CO2吸附量在75℃时达到最大.随着PEHA含量的增加,MCF—PEHA的COz吸附量呈先增大后减小的趋势,当PEHA含量为70%(w)时,CO2吸附量达到最大,为3.55mmol·g-1.水汽促进了吸附剂的CO2吸附性能.研究结果还表明,MCF-70吸附剂经过四次吸脱附循环,吸附性能基本保持不变,表现出很好的可再生性能.
Mesocellular silica foam (MCF) was prepared using P123 (EO20-PO70-E20) as template and then functionalized with pentaethylenehexamine (PEHA) for CO2 adsorption. The samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption- desorption isotherms, Fourier transform infrared (FTIR) spectroscopy and thermal gravimetric analysis (TGA). These results indicated that after modification with PEHA, the structure of the support itself was undamaged. The highest CO2 adsorption capacity of MCF-PEHA was obtained at 75℃. With increasing PEHA loading, the CO2 adsorption capacity increases and approached the highest adsorption capacity (3.55 mmol. g-l) with a 70% (w) PEHA loading. Moisture improved the CO2 adsorption performance of the adsorbents. Repeated adsorption-desorption cycling indicated that the sorbents maintained stable CO2 adsorption capacity after 4 cycles, indicating potential for regeneration of the adsorbents.