Effect of Synthesis Routes and Support Nature on Co-Based Catalysts for Low-Temperature Catalytic Combustion of Methane

High Resolution Image Download MS PowerPoint Slide Catalytic combustion of methane (CH 4 ) is one of the promising methods to tackle the emission of CH 4 through natural gas-based vehicles. Herein, to study the impact of different preparation methods and support, a series of monometallic cobalt-based catalysts was prepared to examine the total oxidation of CH 4 at low temperatures. With a 20% total metallic loading, the samples were synthesized using two different methods: wet impregnation and coprecipitation, with two different types of support, such as cerium oxide (CeO 2 ) and silica oxide (SiO 2 ). All prepared samples were characterized using several techniques to examine their physicochemical properties, such as XRD, Raman, FTIR, SEM-EDS, XPS, H 2 -TPR, and O 2 -TPD, which confirmed the crystalline phases and structural integrity of the catalysts. Structural and surface analyses confirmed that Co incorporation into CeO 2 generated oxygen vacancies and stabilized Co 3+ with high oxygen mobility and reducibility, whereas SiO 2 -supported catalysts showed weaker dispersion and limited redox activity. The catalytic performance of all prepared samples was investigated in the temperature range of 250–600 °C, and CeO 2 -based catalysts synthesized through the wet impregnation method exhibited 91% conversion at 600 °C, which is 25% higher than that of their SiO 2 -based counterpart due to the formation of oxygen vacancies, which enhanced the catalytic activity. The robustness of the best-performing catalyst was tested by varying the WHSVs to check the performance under real conditions. The findings from this study pave the way for the development of low-temperature catalytic processes for methane oxidation.