(685c) Carbon Dioxide Capture Performance of Immobilized Amine Aminosilane Sorbents

Immobilized amine sorbents were prepared by using a hyper-branched polyethyleneimine (PEI) that was cross-linked with various aminosilanes (AS) to promote stability under high water simulated flue gas conditions. The PEI/AS was immobilized within silicon dioxide (SiO2) based substrates at various weight ratios and was tested in dry and moist simulated flue gas conditions (up to 90% moisture by volume) to determine the optimum formulation for these PEI/AS cross-linked sorbents. Initial performance capture capacities of these PEI/AS cross-linked sorbents were also determined by thermogravimetric analyses (TGA) in both dry and humidified CO2 gas streams to determine loading capacities. The regenerable PEI/AS cross-linked sorbents investigated in this study exhibit acceptable CO2 capture capacities of 2.5 to 3.5 mole CO2/kg sorbent as determined in testing with TGA and a laboratory-scale fix bed reactor. PEI/AS cross-linked sorbents were stable over the adsorption/desorption temperature range of 25-105 oC for multiple cycles under dry and high water simulated flue gas conditions. Furthermore, these PEI/AS cross-linked sorbents were scaleable for production and will be tested in a pilot scale capture reactor. The performance of these PEI/AS cross-link sorbents under the described conditions will be discussed in this paper.