(269f) Flame Synthesized CaO Based Sorbents for CO2 Capture – Influence of Metal Ions As Dopants

Growing energy demand and subsequent CO₂ production call for highly efficient CO₂ capture process, which is benign to the environment. Flame synthesized doped Calcium-based novel refractory sorbents have shown excellent performance in CO₂ adsorption. In our previous studies we incorporated several metals (Co, Si, Ti, Cr, Hf, W, Y, La, Ce, Zr) into calcium oxide lattice to improve stability of the sorbent during the CO₂ adsorption experiments. Among these dopants, Zirconia doped CaO with molar ratio of 10:3 showed enormous adsorption stability during 100 cycles of operation. We reported that formation of orthorhombic structured CaZrO₃ in CaO-Zr sorbent is responsible for the observed stability. However, Ca/Zr (10:3) sorbent exhibits lower adsorption capacity. Therefore the present study mainly aimed at finding a different metal dopant ion which can stabilize the CaO sorbent during multi-cyclic operation as well as exhibits high adsorption capacity. For this purpose various metal doped CaO based sorbents were synthesized using flame technique. The sorbents were characterized by BET, XRD, SEM and TEM techniques. CO₂ capture experiments were performed in a TGA at 700 ^oC. Among the various dopants Al doped CaO sorbent exhibit optimal performance. The optimal sorbent were tested under severe condition of high temperature. These interesting findings will be discussed in the presentation.