CO2 adsorption on amine functionalized MCM-41: Effect of bi-modal porous structure

• A Bi-modal Porous Structure MCM-41 was synthesized using hard casting of carbon black nanoparticles.
• The amine grafted adsorbent was prepared by grafting tri-amine on BPS-MCM-41.
• The grafting conditions were optimized by Taguchi technique.
• The optimum adsorption capacity was 2.31 mmol/g.

In this study, a series of experiments was carried out to find the optimum condition for grafting 3-[2-(2-Aminoethylamino)ethylamino]propyltrimethoxysilane (here after TRI) on bi-modal porous structure MCM-41 (here after BPS-MCM-41). The Taguchi experimental design L9 orthogonal array (OA, three factors in three levels) was applied to investigate the effect of temperature, water to solid support ratio, and TRI to solid support ratio on the amine grafting and CO2 adsorption performance of amine grafted BPS-MCM-41 structure. The ratio of adsorbed CO2 to consumed TRI was selected as the objective function of optimization. The optimum conditions for the BPS-MCM-41 were 85 °C, the water to support ratio of 0.3 cc/g, and the aminosilane to support ratio of 1.5 cc/g. The amine grafting of BPS-MCM-41 in this condition resulted in 2.31 mmol/g adsorption capacity. The analysis of variance (ANOVA) showed that the most significant effect on the response was exerted by the amount of TRI used, while the reaction temperature was found to be the least influential.

Figure optionsDownload as PowerPoint slide