(724a) Flame Spray Pyrolysis Synthesis of Durable Doped-CaO Nanosorbents for CO2 Capture – Study of Sulfur Tolerance

Gunugunuri, K. R., University of Cincinnati
Smirniotis, P., University of Cincinnati
Koirala, R., University of Cincinnati

In our previous study, calcium oxide based novel refractory sorbents were synthesized via Flame Spray Pyrolysis (FSP) method for CO2 capture. A wide range of refractory dopants Si, Ti, Cr, Co, Zr, and Ce were doped into CaO and their CO2 capture capacities/characteristics were evaluated using TGA. Among all the doped CaO sorbents, Zr-doped CaO with atomic ratio 3:10 was found to show excellent durability for CO2-capture up to 100 cycles. However, the observed uptake was lower compared to that of pure CaO due to the relatively large number of zirconium atoms present in the Ca/Zr sorbent. The present study primarily focuses on the development of novel doped CaO sorbents using FSP which can exhibit higher molar conversion as well as excellent durability. For this purpose, various dopants Hf, W, La, and Cs were incorporated into the CaO lattice following FSP synthesis. The catalysts thus synthesized were characterized by BET, XRD and TEM techniques and the sorbents performance was evaluated thermogravimetrically. All carbonation experiments were performed with CO2 mixtures simulating industrially relevant conditions. To check the durability, 100 cycles of carbonation-decarbonation were performed over all the sorbents. The experiments were also performed in the presence of sulfur to verify sulfur tolerance of all the doped CaO sorbents. These results will be discussed in this presentation.