Aminosilane-functionalized cellulosic polymers for increased carbon dioxide sorption

Improvement of the efficiency of carbon dioxide (CO2) separation from flue gases has been identified as a high-priority research area to reduce the total energy cost of carbon capture and sequestration technologies in coal-fired power plants. Efficient CO2 removal from flue gases by adsorption systems requires the design of novel sorbents capable of capturing, concentrating and recovering CO2 on a cost-effective basis. The preparation of a novel aminosilane-functionalized cellulosic polymer sorbent by grafting of aminosilanes showed promising performance for CO2 separation and capture. A strategy for the introduction of N-(2-aminoethyl)-3-aminoisobutyldimethylmethoxysilane functionalities into cellulose acetate backbone by anhydrous grafting is described in this study. The dry sorption capacity of the aminosilane-functionalized cellulosic polymer reached 27 cc (STP) CO2/ cc sorbent at 1 atm and 39 cc (STP) CO2/ cc sorbent at 5 atm and 308 K. Exposure to water vapor slightly increased the sorption capacity of the sorbent, suggesting its potential for rapid cyclic adsorption processes under humid feed conditions. In addition, a strategy for the preparation of a cellulose acetate-titanium(IV) oxide sorbent by the reaction of cellulose acetate with titanium tetrachloride is presented. The organic-metal hybrid sorbent presented a sorption capacity of 14 cc (STP) CO2/ cc sorbent at 1 atm and 49 cc (STP) CO2/ cc sorbent at 5 atm and 308 K. The novel CO2 sorbents were characterized in terms of chemical composition, density changes, molecular structure, thermal stability, and surface morphology.MSCommittee Chair: Koros, William J.; Committee Member: Jones, Christopher W.; Committee Member: Mulholland, Jame