Amine-modified mesoporous silica as novel adsorbent for CO_2 capture and separation from flue gases was prepared by grafting various aminosilanes; i.e., (3-aminopropyl) triethoxysilane (APS), N-(2-aminoethyl)-3-aminopropyltriethoxysilane (AEAPS) and (3-trimethoxysilylpropyl)diethylenetriamine (TA), on mesoporous silica, SBA-15. Pore walls of SBA-15 were modified uniformly with these aminosilanes, and relatively high surface area and uniform pore size were retained. Adsorption capacities of CO_2 in the presence of water vapor were compared with that in the absence of water by a flow method. It was found that adsorption capacities of amine-modified SBA-15 under wet condition were comparable to that under dry condition. In particular, the adsorption capacity of TA-anchored SBA-15 reached 1.28 mol·kg~(-1) in the presence of water vapor at 333 K. In addition, these adsorbents were completely regenerated by heating up to 423 K in He flow.
展开▼
