The Oxidative Coupling of Methane (OCM) reaction [1] holds significant potential for the production of valuable products from methane. However, it is confronted with several challenges, including low selectivity towards the desired products and high energy requirements for the reaction conditions. As a result, ongoing research efforts are focused on developing more effective catalysts and optimizing reaction conditions to enhance the selectivity and efficiency of the OCM process [2-4]. In this investigation, we synthesized three distinct variants of Mn-Na 2 WO 4 /SiO2 catalysts, employing different compositions ranging from 4% to 6%. The catalytic performance of these catalysts, designated as A, B, and C, was initially evaluated for the oxidative coupling of methane (OCM). The experimental conditions included a total flow rate of 480 mL/min, with methane-to-oxygen ratios of 2 and 4. Among the catalysts tested, catalyst A exhibited remarkable efficacy in generating C 2 H4 and C 2 H6 products compared to catalysts B and C. To further characterize the catalytic behavior, methane conversion and selectivity towards C 2 hydrocarbons were determined for catalysts A, B, and C at three distinct temperatures: 800, 825, and 850 °C. Notably, the desired catalysts displayed enhanced performance at elevated temperatures. Additionally, the highest conversion of reactants was achieved when the methane-to-oxygen feed ratio was set to 2, specifically at a temperature of 800 °C. To evaluate the properties of the synthesized catalyst, various characterization techniques such as X-ray diffraction (XRD), Fourier- transform infrared spectroscopy (FTIR), temperature-programmed reduction (TPR), Brunauer- Emmett-Teller (BET) surface analysis, and field emission scanning electron microscopy (FESEM) were employed.

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