(269d) Composite Metal Oxide Materials Synthesized by Ultrasonic Spray Pyrolysis for CO2 Capture in a Sorption-Enhanced Water-Gas-Shift Process
Combining high-temperature CO2 adsorption with the water-gas-shift (WGS) reaction has several advantages over conventional integrated gasification combined cycle power plants, which presently uses solvent-based CO2 capture (e.g. SelexolTM): high-temperature sorption of CO2 in a sorption-enhanced water-gas-shift (SEWGS) process would eliminate the need for multiple catalytic WGS reactors and for a separate low-temperature CO2 capture unit and would avoid gas cooling and reheating steps prior to entering a gas turbine. Developing a cost-effective sorbent with a stable working capacity under WGS conditions, however, has still remained a challenge.
In this work, for the first time, we report a facile synthesis of composite CaO-based materials for SEWGS applications via ultrasonic spray pyrolysis (USP). USP is a continuous and industrially scalable method for synthesis of materials with different morphologies. Materials here consist of inert refractory metal oxides dispersed in a CaO matrix. Inert additive oxides can provide structural stability for the sorbents at high temperature. A variety of characterization methods such as SEM, (S) TEM, XRD, and TGA were employed in order to explain the performance of sorbents during multicycle testing of CO2 adsorption and desorption. A few sorbents were identified to be promising and have undergone further testing under simulated WGS reaction conditions. Finally, the possibility of synthesis of hybrid sorbent/catalyst materials via USP will be discussed in this presentation.