| Coupling of Mechanochemical Synthesis with Enhanced Microwave Chemistry towards Biogas Dry Reforming Catalysts Kyriaki Polychronopoulou1; Sara Alkhoori1; Aseel Hussien2; 1KHALIFA UNIVERSITY, Abu Dhabi, United Arab Emirates; 2KHALIFA UNIVERSITY OF SCIENCE AND TECHNOLOGY, Abu Dhabi, United Arab Emirates; PAPER: 252/AdvancedMaterials/Regular (Oral) SCHEDULED: 15:15/Fri. 25 Oct. 2019/Leda (99/Mezz. F) ABSTRACT: In the present study, enhanced microwave (EMW) synthesis, where microwave radiation is coupled with reflux conditions, was used to prepare CeO<sub>2</sub>, CeO<sub>2</sub>-La<sub>2</sub>O<sub>3</sub>, and CeO<sub>2</sub>-La<sub>2</sub>O<sub>3</sub>-10% Cu catalysts. Ceria has become a promising material that features high redox properties, high population of oxygen vacancies [Ovac], that are crucial for hydrocarbon catalytic reactions such as CO<sub>2</sub> reformation of methane (dry reforming of biogas) [1-3]. This is crucial in the sense that they contribute to coke reduction. Post synthetically, the catalyst CeO<sub>2</sub>-La<sub>2</sub>O<sub>3</sub>-10% Cu was ball milled under both, wet and dry conditions. The ball milling technique is expected to further improve the oxygen vacancies and give higher efficiency for uniform multi-component mixed oxides in consideration of time and energy usage. The prepared catalysts were characterized using x-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Remarkably, the EMW synthesis conditions affect the crystallinity of the catalysts (XRD) and the crystal growth, generating particles with crystallite size in the ranges of ~11-19 nm. The ball-milled catalysts exhibited a smaller crystallite size ~9.5 nm (XRD), which corresponds to larger surface area (m<sup>2</sup>/g). This, in fact, enhances oxygen mobility in the ceria support lattice and yields to the formation of more O vacancies. References: [1] ND Charisiou, G Siakavelas, L Tzounis, V Sebastian, A Monzon, MA Baker, SJ Hinder, K Polychronopoulou, IV Yentekakis, MA Goula, International Journal of Hydrogen Energy 43 (41), 18955-18976 [2] ND Charisiou, K Polychronopoulou, A Asif, MA Goula Surface and Coatings Technology 352, 92-111 [3] ND Charisiou, A Iordanidis, K Polychronopoulou, IV Yentekakis, MA Goula Materials Today: Proceedings 5 (14), 27607-27616 |
