(560bk) Extrusion of Perovskite Oxide/ Silica Composites for Thermochemical Carbon Dioxide Conversion

Perovskite-type oxides have been used to convert CO₂ to CO in a reverse water-gas shift chemical looping (RWGS-CL) process. Currently, the process is at the micro-reactor scale and used catalyst in powder form. However, formed materials are needed if the scale is to be increased. Our research focus is on increasing the conversion yield of perovskite oxides with SiO₂ support and scaling up the powder form perovskite-type oxides to pellet by extrusion. The binder added during the extrusion process must be removed to avoid affecting the performance of the catalyst and to provide porosity, without substantially lowering the mechanical strength. X-ray diffraction was utilized to identify the crystal structure and determine the crystal stability after the conversion. Temperature programmed reduction (TPR) and temperature programmed oxidation (TPO) experiments were performed to identify the conversion temperature and redox properties of the materials. Compared to pure perovskite-type oxides, sample La_0.75Sr_0.25FeO₃ mixed with SiO₂ (mass ratio was 50:50) had better conversion performance and stronger mechanical strength after extrusion.