Experimental Investigation of CO2 Capture Capacity: Exploring Mesoporous Silica SBA-15 Material Impregnated with Monoethanolamine and Diethanolamine

• Published in: Energy & fuels Vol. 30; no. 11; pp. 9554 - 9562
• Main Authors: Chen, Hongwei, Liang, Zhanwei, Yang, Xin, Zhang, Ze, Zhang, Zhiyuan
• Format: Journal Article
• Language: English
• Published: American Chemical Society 17-11-2016
• ISSN: 0887-0624; 1520-5029
• DOI: 10.1021/acs.energyfuels.6b01298

A series of efficient adsorbents were prepared by impregnating mesoporous silica SBA-15 with different amounts of mono­ethanol­amine (MEA) and diethanol­amine (DEA) in order to improve CO2 capture capacity. The textural properties of pure and modified mesoporous SBA-15 materials were characterized by X-ray diffraction characterization, transmission electron microscopy, N2 adsorption–desorption test, and thermogravimetric analysis. When the ratio of DEA to SBA-15 is below 2, these molecules loaded on the support are relatively far away from saturating and allow the accessibility of CO2 molecules to the inner adsorption sites. Further increasing of the amine loading would reduce opportunities of CO2 to contact with internal amino sites, because the amine was covered in a multilayer form or even caking form on the SBA-15 pore surface. The similar performance was observed for MEA. Therefore, the adsorption capacity of CO2 increases with the amount of DEA or MEA content, but when the amount of MEA or DEA loaded on the mesoporous SBA-15 is further increased, the CO2 capture is influenced by the packing effect on the mesoporous hexagonal silica. Temperature effect on adsorption was also studied in the range of 30–90 °C, showing that, with the increase of temperature, the adsorptive amounts of adsorbents lessened gradually from the highest values at 30 °C since the thermodynamically controlled process. The mesoporous SBA-15 material impregnated with MEA or DEA can provide a perspective to further explore effective adsorbents for CO2 capture.